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#176 2017-05-07 06:34:07

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,548

Re: Air. Shelter. Water. Food.

RobertDyck wrote:

What's up with this obsession about 3D printers? They're a tool. All tools are useful but have limits. Don't try to do everything with the same tool.

Can you understand that even though a bit driver is also just a tool, you don't need 50 different screw drivers when a couple bit drivers and 50 different bits do the exact same thing for less weight and money?

Apparently some people here think I want to open a microchip and rocket engine factory on Mars simply because I wanted to take a handful of useful tools to repair things that those tools can easily repair.  I don't know how many times I'd have to state the exact opposite for it to actually sink in.

RobertDyck wrote:

You want to unsolder work done by a human, and do it over again by machine? What? That's backwards. The machine makes mistakes. A human has to check quality, and if the machine made a mistake the human fixes it. This sounds like you assume all humans are incompetent.

Jesus H on a Crutch.  I said the opposite.

kbd512 wrote:

If a human damages a circuit board, a printer can repair the existing circuit board.

I guess I'm the only one, but to me that sentence meant that I intended for the machine to do the soldering jobs.  Perhaps I should write shorter sentences, but "human damage, machine repair" seemed to convey less of what I intended.  In any event, the humans will eyeball the work being done and fetch any needed parts for the machine to use to effect the repair.

As it pertains to mistakes, machines don't make mistakes.  Humans make mistakes.  Machines do exactly what the humans programmed the machines to do.  All humans are incompetent, it's just a question of what they're incompetent at doing and whether or not whatever they're incompetent at doing has lethal consequences.

RobertDyck wrote:

Again, why the printer? Are you assuming crew don't have any skill? If a human strips a thread, a human can use an arc welder to fill the hole. Then either a drill press, or just a drill stand for a hand drill. Someone with skill can drill a vertical hole with a hand drill alone, no stand. Then use a hand tool called a tap to cut threads. The most complicated tool is the arc welder.

I don't want to teach a human how to weld aluminum, how to weld titanium, and how to weld steel.  I don't want a human or robot welding in or near a pressurized vessel, if at all possible.

I don't want to teach a human how to repair rocket engine parts, how to repair circuit boards, or how to repair seals.  I want a human to know how to test the function of a part, how to interpret test results, and how to correctly disassemble and reassemble the components.  If they don't lose any parts, that's a bonus.

I would rather teach humans general information about what they're doing and how to go about doing it.  I would rather they know whether or not a job was done sufficiently well to avoid kill anyone rather than constantly practicing the mechanical skills required to complete every step of every possible task.

If the humans know what piece of equipment to attach to a robot to do a job, then they don't have to spend time learning how to drill perfectly straight holes.  If they can't figure out how to put tools in a machine or robot, then we don't need them.  I think we've already done that here on Earth.  There aren't very many people left who make things by hand.  We've specialized for reasons of efficiency and repeatability.

In any event, I'm sick of arguing the point of why a bit driver is better than 50 different screw drivers when weight, volume, and cost are all factors to consider when deciding what goes and what stays.  Take your hand tools to Mars and see how long it takes for someone to die because they made a mistake and didn't have sufficient skill, practice, or training to correct the mistake.

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#177 2017-05-07 08:04:34

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,414

Re: Air. Shelter. Water. Food.

Most of the equipment we've been discussing is going to be high tech designed, but built as low tech as possible. Remember the KISS principle. Certain pieces of equipment will undoubtedly have backups, but it would also be nice for repairs to be possible on the breakdown/defective apparatus. That case, yes, we need tools, backup wear parts, but most importantly, the necessary skills to fix things. Robotics and ability to replicate parts seems to be prudent.

Last edited by Oldfart1939 (2017-05-07 08:26:06)

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#178 2017-05-07 08:16:50

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,178

Re: Air. Shelter. Water. Food.

Topic is quickly moving so here is some links and with anything using a wire....
http://www.atlanticprecision.com/3d-printing-copper/
https://www.nasa.gov/marshall/news/nasa … -part.html

some of the 3D machines for metal start with wire spools and some with the powder So if we send each unit tpe we have what we need to remainufacture any motors that do not function all the wire needs is an insulating varnish or shelac to coat it so that it will not short out on its self as we reman the motors. The same machines can make shaft components for that same motor but we will still need a lubricant for them. Brushes are made from carbon so I thick we will be able to make these as well.

http://colorfabb.com/copperfill
http://www.sciaky.com/additive-manufact … industries

Electronics 3d printing is improving and may be there for the simple components but for those very large scale devices it may be a bit.
https://3dprint.com/53785/feam-3d-print-wires/

They can for the arc welding of a hole also use the metalized epoxies for fill....

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#179 2017-05-07 10:07:44

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

RobertDyck wrote:

Apollo 11 landed on the Moon: July 20, 1969
Apollo 17 splashed down: December 19, 1972

That's how quick it was cancelled. Apollo used all expendable equipment.

Shuttle first launch: April 12, 1981
Shuttle last flight: July 21, 2011

It flew for 30 years. That's what you get with reusable equipment. Robert Zubrin wants a Mars mission with entirely expendable equipment. I argue for the interplanetary vehicle to be reusable. This is one reason why.

Skylab launch: May 14, 1973
Skylab first human mission, launch: May 25, 1973
Skylab last human mission, splashdown: February 8, 1974
Skylab uncontrolled deorbit and crash: July 11, 1979

Skylab was required crew to operate it. It had food, oxygen, water, and lithium hydroxide canisters to scrub CO2 for many more days than it was occupied. The 4th crew mission to Skylab was cancelled. This is what happens when you need constant resupply. And Skylab only required crew, it had on-board supplies for many more missions.

Robert Zubrin does not want a Mars mission with entirely expendable equipment.  Having a spacecraft take a crew to Mars and act as a habitat on Mars is not wasting it, it's not throwing it away.  It's being used for a very important purpose, a purpose that is much more important than making money for a billionaire. 

Every space mission that has needed constant resupply has been cancelled?  Cancelled so we could move on to something else.  Here's how you make sure a Mars colony doesn't get pulled off of Mars, you make it successful.

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#180 2017-05-07 10:22:01

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

kbd512 wrote:
Dook wrote:

Why do I think hundreds of pounds of powders are required?  If you want to print metal components, not just circuits, then you need metal powder, not just conductive ink.  You've said you would take multiple 3D printers.  Plus, you've stated that we could print seals, so you need synthetic rubber and plastic.

Do you need more or less material to resurface a piece of rubber?

Dook wrote:

Aerospace manufacturers don't use 3D printers to make brackets?  So 3D printers can't even make brackets?

So you're still stuck on this bracket nonsense?

Dook wrote:

What the hell is a dust imager?  Don't know, but there's one in the Moxie.  Engineers always over-design things.

The engineers probably want to know how fast the dust degrades MOXIE by measuring the particulate sizes ingested.  That way, they don't have to "over-design" a piece of production equipment.  I don't have a "fly imager" in front of the radiator on my car, since the engineers determined about a century ago that the flies wouldn't hurt the radiator.  It's a safe bet that a test apparatus from a science experiment has little to do with a piece of production hardware.  The good news is that you won't need spare test equipment from a science experiment.

Dook wrote:

I would need 24 lead acid batteries to run the Marscat for one hour?  No, I wouldn't.  Deep cycle batteries have 900 cold cranking amps at 12 volts (Watts = Amps x Volts), so that is 10,800 watt hours, not 900 watt hours.  I think eight to ten batteries would provide one or two hours a day of use and then they would be recharged.  We don't want to run them down too much.

Battery capacity is measured in amp-hours, or "AH".  If the capacity of a 12 volt battery is 75 amp-hours (75AH), then that means it can deliver a maximum of 75 amps of current for one hour at a voltage of 12 volts.  You get less than that in real life, but I'm trying to keep this simple.

Cranking amps are a marketing tool used to tell people how fast their battery can discharge without using confusing them with terms like energy density (how many watts of power the battery can store for a given volume and mass) and power density (how many watts of power the battery can deliver in a given unit of time).

The "900 cold cranking amps" in your example means the battery can deliver a maximum of 10.8kW of electrical power to an electric starter motor (1hp = 745.7W, so 14.48hp, assuming 100% conversion efficiency), but if you try to discharge a 75AH Lead-acid battery that fast it'll be completely discharged in 5 minutes.

60 seconds * 60 minutes per hour = 3,600 seconds per hour

10,800 watt-hours divided by 3,600 seconds per hour = 3 watts per second

3 watts per second * 60 seconds = 180 watts per minute

180 watts per minute * 60 minutes = 10,800 watts per hour

P (power in watts) = I (current flow measured in terms of amperes or amps) * V (electrical potential difference measured in terms of volts)

900 (watt-hours) = 75 (amp-hours) * 12 volts

900 watts / 180 watts per minute = 5 minutes at a discharge rate of 10,800 watts per hour (900 cranking amps at 12 volts)

5 minutes is the maximum length of time any 12 volt 75AH battery (irrespective of what type it is, Lead-acid, Lithium-ion, Nickel Metal Hydride, Graphene, etc) would deliver current at a rate of 10.8kW per hour.  Like I said previously, it's less than that in real life if you don't want to destroy the battery.  Going past 80 DoD (Depth-of-Discharge) is typically not conducive to long battery life.

Peukert's Law also affects battery capacity as a function of discharge rate.

t = H(C / (IH))^k

t [time] = H [hours] ( C [capacity in amp-hours] / (I [current in amps] * H [hours]))^k [Peukert's exponent; differs for every battery]

The equation shown above does not account for temperature, number of cycles already completed (causes the Peukert exponent to increase), or self-discharge.  This is just extra stuff for you to use to figure out exactly how long a battery can be discharged.  You'll need to get the Peukert exponent from the manufacturer.  If you get this information, then you can get a reasonably good idea of how the battery will actually perform.  Temperature is also critical.  Battery capacity diminishes in cold temperatures and increases in warmer temperatures up to a certain point.

Now that you know how to correctly calculate battery capacity, do you still want to use Lead-acid?

Dook wrote:

Lithium-ion batteries store more energy than lead-acid, there's no doubt about it, but they short out too often and catch fire.  We can't have that on a spacecraft.  Now, the lithium-ion batteries for the Marscat could possibly be assembled on Mars so there's no risk to the spacecraft in flight.

ISS uses lots of Lithium-ion batteries and there have been no fires aboard ISS from Lithium-ion batteries.

Dook wrote:

The lead-acid batteries for the Marscat and Long Range Rover could have the batteries empty of water and then add the water on Mars.  That might provide more safety from any kind of short happening in any of those batteries from launch vibration or aero-capture.

Properly designed Lead-acid batteries won't short, either.

No one, not even people in a settlement on Mars is going to attempt to resurface a rubber seal.  They would replace it entirely and throw the old rubber seal away. 

I'm stuck on this bracket nonsense?  Then explain all the important things you are going to make with a 3D printer on Mars.  Still waiting...

Do I still want to use lead-acid batteries?  Yes.  Do you still want to risk the entire spacecraft and crew lives by shipping multiple lithium-ion batteries?

ISS uses lots of lithium-ion batteries and there have been no fires?  There are video's on the internet of people's phones catching fire.  It's rare but it happens in lithium-ion batteries much more than lead-acid batteries.   

Properly designed lead-acid batteries won't short either?  Vibration from launch, aero-capture, parachute deployment, and landing could cause a battery to short.  You would have to have batteries powering the Mars Hab but the batteries in the rover or Marscat wouldn't have to be powered.  You could install the acid plates on Mars and add water.

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#181 2017-05-07 10:22:21

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,836
Website

Re: Air. Shelter. Water. Food.

Dook wrote:

Every space mission that has needed constant resupply has been cancelled?  Cancelled so we could move on to something else.  Here's how you make sure a Mars colony doesn't get pulled off of Mars, you make it successful.

Apollo was successful. Skylab was successful. They were both cancelled.

In the 1970s, NASA had a proposal for an international space station. Launch a Skylab workshop on a Saturn 1B rocket. Launched the way Skylab was designed to be launched: wet. No Apollo telescope mount, no multiple docking adapter, and no even an airlock. The next launch would be an Apollo CSM with the airlock, carried in the space where an LM would normally go. This would launch into LEO on a Saturn 1B, which missions to Skylab had used anyway. The Apollo CSM would turn around and dock to the airlock, like it did to the Apollo LM, then carry the airlock to the Skylab workshop. This means an airlock would be installed before crew enter the station. The next mission would also be with crew, an Apollo CSM with the multiple docking adapter. Then another unmanned launch, another Skylab workshop launched wet. It would have to rendezvous and dock autonomously. This would provide 2 Skylab workshops, with the airlock and multiple docking adapter between. Canada and Europe wanted to be part of an international space station even then. The plan was their modules would attach to the multiple docking adapter. Skylab as launched only had 3 ports on the multiple docking adapter: fore, aft, and one on the side. But this station would have 6 ports, just like a modern node on ISS: fore, aft, left, right, top, bottom. This would have required a total of 4 launches of Saturn 1B rockets, each cost less than a single launch of Shuttle. And 6 months from first launch to US core complete. Total interior volume would have been greater than ISS today.

But it didn't happen. Easy to do using technology of the day. It was the next obvious upgrade. But it didn't happen. So don't tell me about "moving on". This is just abandoning expensive infrastructure. Just because they didn't want to continue supply.

Last edited by RobertDyck (2017-05-07 10:23:03)

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#182 2017-05-07 10:49:20

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

kbd512 wrote:
Dook wrote:

Okay, I looked at the CAMRAS and, near as I can tell, these are the main components:

Aluminum body
Dessicant wheel and small motor
Porous plastic beads coated with an amine
Two temperature sensors
Blower
Vacuum jumper hose
Absorbing bed
Desorbing bed
Seals
Air save tank
Electronics box

I don't believe the small 3D printer that makes electronics can make larger solid metal components.  I could be wrong, but the small electronics one just sprays hot silver, whereas a 3D printer that spray metal powder uses a laser to melt the powder. 

So, of the above CAMRAS components, a 3D printer for spraying hot silver for making electronics and another 3D printer with a laser for spraying metal can make some of the pieces of a blower, a vacuum hose, it might make seals if they are rubber seals, not if they are compression fibrous material seals, electric motor case, and it would make some electronics.

I am by no means suggesting that we don't take backup MOXIE, CAMRAS, or IWP units.  I think triple redundant life support systems should be standard for any extended mission duration spacecraft, but that means 3 complete units.  If more than 3 complete life support systems are required in a span of two years, then there are serious design issues to address and that should probably be done before the exploration phase begins.  If you have to take an entire hardware store to Mars to ensure that whatever needs to be repaired gets repaired, then something is wrong with the basic design.

We already know how things fail and can even predict when things will fail from testing.  I'm trying to account for stupid human mistakes (wrong parts sent; if you have different versions of the same equipment then the likelihood of this happening increases, replacement part still fails because of defective design, human accidentally broke a working unit doing something stupid during maintenance or operation) by sending 3D printers, not rebuilding entire pieces of life support equipment from scratch.

If a human damages a circuit board, a printer can repair the existing circuit board.  If a circuit board was 3D printed to begin with, then another printer can literally unsolder and re-solder components on the board.  Voxel's technology takes account of the fact that humans make mistakes.

If a human strips a thread on a screw hole, a printer can fill it in.  The requirement for a second head to drill and re-thread the hole does not mean a gigantic drill press.  After the filling in the hole with a metal print head, switch the tool to a drill, drill the hole, switch the tool to a tap, and then thread the hole.  The colonists need tools to begin with and Robonaut was designed to use human hand tools.  The difference is that humans aren't capable of repeatable movements requiring sub-millimeter precision or working outside 24/7 without food, water, or oxygen.  Humans get tired, hot, cold, hungry, and thirsty.  The robot never does.

If a human drops and breaks an aluminum plate of the kind that electronics, MOXIE, CAMRAS, and IWP use as chassis material, then the printer can weld the plates back together or repair the chip taken out of the plate with very little in the way of fixturing.  There are a limited number of alloys typical to spacecraft electronics and life support equipment design and since we already have the engineering design specs for all the systems, we can probably remember to send the right kinds of powdered metals and screws or nuts and bolts.

We need 1 print head for circuitry, 1 print head for metals, 1 print head for plastics, and 1 print head for rubbers or sealants.  The metal print head will be heavier and require more power than the rest.  Volumetrically, the print heads are about the size of large screw driver handles.  We'd have 1 print enclosure with XYZ axis servos for stationary printing (broken things inside the pressurized module) and 1 robot for mobile printing applications (broken things outside the pressurized module).

You think we should have triple redundant life support systems?  I'm fine with that.  I figured two mini-Moxies and enough spare parts to fix both of them once, an emergency air bottle, and the Mars Suit rebreathers would be good but having three mini-Moxies is better. 

Having two, or three, CAMRAS machines would be good and they could have the absorbent canisters as a backup.

I don't think they could have three WAVAR machines because they are just too big and heavy.  Having one with spare parts would have to do it. 

You're trying to account for stupid human mistakes by sending 3D printers?  They just don't do nearly enough to justify their weight and space. 

If a human damages a circuit board?  Everything will be tested before flight.  If something happens in flight the crew will replace the entire circuit board.  They're not going to be able to use a 3D printer in zero gravity. 

The Voxel 8 sprays a tiny stream of conductive ink onto a fiberglass circuit board.  It can't unsolder.  Some of the 3D printers are actually just sprayers.   

If a human strips a hole the 3D printer can fill it in?  How are you going to get a whole Moxie, or whole CAMRAS, or WAVAR unit over to the 3D sprayer?  We already have ways of fixing stripped threads, it's called a helicoil.

Robonaut was designed to use human tools?  If there are machines that can do things that humans do then we can send Robonaut and not risk lives.  Why are there humans on the ISS if robonaut is there?

The 3D printer can weld cracked aluminum back together?  The 3D printers don't have a laser scanner.  They can't scan a crack and determine the correct amount of heat and material to fix the crack on their own, someone would have to manually run the aluminum back and forth under the 3D printer as it sprayed.  So, would that work, yeah, it would be like welding but welders practice for months to get good at it.   

You just need 4 print heads for a 3D printer and then you can do everything?  The Voxel 8 just sprays conductive ink, it doesn't have a laser, so you can't weld with it.  So, you need the Voxel 8 to make circuits.  Then you need another larger 3D printer that has a laser to spray/weld.

Please list all the important components you plan to make with your 3D printer?

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#183 2017-05-07 11:00:54

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,414

Re: Air. Shelter. Water. Food.

O.K., O.K., enough of this contentious "bravo sierra."

What we're ALL  interested in is having  successful outcome to man's first landings on Mars. Whether we use Lithium Ion Batteries or Lead Acid batteries to power the hypothetical rover makes for "interesting discussion," but more importantly, refocus; on the Air; Shelter; Water; Food aspects of the mission. Underlying this discussion is the amount of payload available, the number of crew sent there, and how they'll survive. The technology of water extraction is where we've focused some attention. Zeolite bed capture from the atmosphere? Fine. We've agreed that's a decent technology for pursuit. Air (Oxygen extraction) is also a "given" vis a vis the Moxie units. The upgraded Mars Direct models now indicate the production of LOX may streamline the first missions by carrying the return fuel whilst still manufacturing return flight oxidizer (75 % of the mass needed).

At the moment, we're all busting our gums arguing about future details when we should be campaigning vigorously for the first mission---ANY mission--that indicates follow up manned spaceflight. We need to move forward from the 1989 concepts in view of advanced orbital assembly abilities and ISS availability. This is, as Dook stated, about making the missions SUCCESSFUL. The main take-home concept supplied by Zubrin is ISRU. Any other approach is simply out of reach. At present, we're strictly limited by current chemical propulsion technology, and the only bodies within reach are (1) the Moon, and (2) Mars. I personally believe that objective (1) will be the first to succumb to NASA and private-NASA partnerships. Mars isn't far behind, only because of the every 2 year launch windows.

Since I began this thread, I thought I should supply some remediation to participants (self included) to get this discussion back on line.

Last edited by Oldfart1939 (2017-05-07 11:07:22)

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#184 2017-05-07 11:04:06

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

SpaceNut wrote:

Topic is quickly moving so here is some links and with anything using a wire....
http://www.atlanticprecision.com/3d-printing-copper/
https://www.nasa.gov/marshall/news/nasa … -part.html

some of the 3D machines for metal start with wire spools and some with the powder So if we send each unit tpe we have what we need to remainufacture any motors that do not function all the wire needs is an insulating varnish or shelac to coat it so that it will not short out on its self as we reman the motors. The same machines can make shaft components for that same motor but we will still need a lubricant for them. Brushes are made from carbon so I thick we will be able to make these as well.

http://colorfabb.com/copperfill
http://www.sciaky.com/additive-manufact … industries

Electronics 3d printing is improving and may be there for the simple components but for those very large scale devices it may be a bit.
https://3dprint.com/53785/feam-3d-print-wires/

They can for the arc welding of a hole also use the metalized epoxies for fill....

The copper 3D printer can make electronic parts and wire. 

That might sound great, having the ability to make new motherboards on Mars, except when you realize that the fiberglass motherboard has to be shipped from the Earth AND the powder has to be shipped from the Earth.  Shipping those two things in order to make a new motherboard on Mars is EXACTLY the same weight as shipping a new motherboard already made. 

The only difference is that it's sprayed on Mars instead of on the Earth.  You're basically sending pieces of a component instead of the component fully assembled.  You're giving them more work to do when the weight is exactly the same as a new component.

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#185 2017-05-07 11:12:19

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

Oldfart1939 wrote:

O.K., O.K., enough of this contentious "bravo sierra."

What we're ALL  interested in is having  successful outcome to man's first landings on Mars. Whether we use Lithium Ion Batteries or Lead Acid batteries to power the hypothetical rover makes for "interesting discussion," but more importantly, refocus; on the Air; Shelter; Water; Food aspects of the mission. Underlying this discussion is the amount of payload available, the number of crew sent there, and how they'll survive. The technology of water extraction is where we've focused some attention. Zeolite bed capture from the atmosphere? Fine. We've agreed that's a decent technology for pursuit. Air (Oxygen extraction) is also a "given" vis a vis the Moxie units. The upgraded Mars Direct models now indicate the production of LOX may streamline the first missions by carrying the return fuel whilst still manufacturing return flight oxidizer (75 % of the mass needed).

At the moment, we're all busting our gums arguing about future details when we should be campaigning vigorously for the first mission---ANY mission--that indicates follow up manned spaceflight. We need to move forward from the 1989 concepts in view of advanced orbital assembly abilities and ISS availability. This is, as Dook stated, about making the missions SUCCESSFUL. The main take-home concept supplied by Zubrin is ISRU. Any other approach is simply out of reach. At present, we're strictly limited by current chemical propulsion technology, and the only bodies within reach are (1) the Moon, and (2) Mars. I personally believe that objective (1) will be the first to succumb to NASA and private-NASA partnerships. Mars isn't far behind, only because of the every 2 year launch windows.

Since I began this thread, I thought I should supply some remediation to participants (self included) to get this discussion back on line.

To get back to air, water, food, and shelter, I think we need to make the WAVAR more simple and efficient.  The U of Washington design uses a circular rack and pinion to spin the zeolite bed into a microwave chamber, zap it, then slowly spin the zeolite back out to have Mars atmosphere flow through it.  I think the zeolite panels should be hard mounted inside a microwave already, and not move.  And the Mars atmosphere should be pulled through the panels and expelled.   

Also, the U of Washington design uses a 6 foot fan that spins at 500 rpm to move 20 meters a second of atmosphere and uses 8 kw.  I think that's too much power even though it's within NASA Design Reference Mission guidelines because NASA plans to send a big nuclear reactor.

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#186 2017-05-07 11:27:14

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,414

Re: Air. Shelter. Water. Food.

What IS indicated here is the need for an experimental unit on one of the upcoming Mars lander missions. NASA? Fine. Red Dragon? Fine. But it needs to be DONE, and not put off to a "later mission." I'm not sure the Moxie will be flown on the 2020 NASA mission. There's been some contention about certain other "critical experiments" by NASA planetary scientists. It seems that NASA cannot get a sense of priorities in accord with manned spaceflight. They simply are "business as usual."

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#187 2017-05-07 11:29:05

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,548

Re: Air. Shelter. Water. Food.

I want everyone to take a good look at these three photos:

This is the pretty artwork showing what the interior of Zvezda would look like:

Zvezda Cutaway

The photo from the link above is what Zvezda looks like in fantasy land.

This is what the interior actually looked like in 2015:

ISS-45_Sergey_Volkov_works_inside_the_Zvezda_Service_Module.jpg

Ignore the camera clutter.  Just take a look at all the computers and wiring.  The panels on all four sides of the module aren't sock drawers for the astronauts.  If you take a panel off, you'll see nearly as much wiring and piping as you'd see in the Space Shuttle.

Here's what the CAMRAS assembly / installation looked like:

Amine Swingbed Assembly

I want someone to tell me which parts in the second and third pictures they think are critical.  If you guess wrong about what's going to fail and how, but have no alternative method to repair critical systems, then the crew may as well dig some shallow ditches and go lay in them because we're going to bury them a few yards from where they once lived.  I want to know where all these spare parts are going if we're going to have spares for everything.  Forget about what it weighs, we'd need another module just to store the spare parts.

If you look at the interior of Orion, you'll see spaces that are likewise filled with electronics, wires, pipes, and valves.  Teams of dozens to hundreds of engineers design and build these things.  That is simply what the interior of modern spacecraft look like and the ISS modules are miniature tuna cans.

People here think the colonists, mostly kids fresh out of college if I understand what the rest of you want to do, will simply be so skilled that they can use their two years of astronaut training and bachelor of science degree to supplant the knowledge and tools that the hundreds of people who built the spacecraft have simply by swapping out parts?  Give me a break.  Earth to space cadets, this is reality calling.  If you don't have adaptable tools and technologies, along with a good number of people back on Earth to support you, your mission will be a lot shorter than you planned.

Where are we putting the RadioShack and Home Depot in the tuna can?  Will the colonists be able to take a step in any direction without tripping over boxes of spare parts?

Last edited by kbd512 (2017-05-07 11:31:01)

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#188 2017-05-07 11:54:07

Dook
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From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

kbd512 wrote:

I want everyone to take a good look at these three photos:

This is the pretty artwork showing what the interior of Zvezda would look like:

Zvezda Cutaway

The photo from the link above is what Zvezda looks like in fantasy land.

This is what the interior actually looked like in 2015:

ISS-45_Sergey_Volkov_works_inside_the_Zvezda_Service_Module.jpg

Ignore the camera clutter.  Just take a look at all the computers and wiring.  The panels on all four sides of the module aren't sock drawers for the astronauts.  If you take a panel off, you'll see nearly as much wiring and piping as you'd see in the Space Shuttle.

Here's what the CAMRAS assembly / installation looked like:

Amine Swingbed Assembly

I want someone to tell me which parts in the second and third pictures they think are critical.  If you guess wrong about what's going to fail and how, but have no alternative method to repair critical systems, then the crew may as well dig some shallow ditches and go lay in them because we're going to bury them a few yards from where they once lived.  I want to know where all these spare parts are going if we're going to have spares for everything.  Forget about what it weighs, we'd need another module just to store the spare parts.

If you look at the interior of Orion, you'll see spaces that are likewise filled with electronics, wires, pipes, and valves.  Teams of dozens to hundreds of engineers design and build these things.  That is simply what the interior of modern spacecraft look like and the ISS modules are miniature tuna cans.

People here think the colonists, mostly kids fresh out of college if I understand what the rest of you want to do, will simply be so skilled that they can use their two years of astronaut training and bachelor of science degree to supplant the knowledge and tools that the hundreds of people who built the spacecraft have simply by swapping out parts?  Give me a break.  Earth to space cadets, this is reality calling.  If you don't have adaptable tools and technologies, along with a good number of people back on Earth to support you, your mission will be a lot shorter than you planned.

Where are we putting the RadioShack and Home Depot in the tuna can?  Will the colonists be able to take a step in any direction without tripping over boxes of spare parts?

We don't have to guess.  We already know a 3D printer CAN'T make 90% of life support components.

You want to know where all the spare parts are going?  They're going in a case strapped to the floor of the Zubrin science lab. 

We'd need another module just to store the spare parts?  Not even close.  Once again, here are the spare parts that we need to fix the two Moxies:  two new P sensors, two new dust imagers, two new accumulator o-ring kits, two new CO2 condensers, two new electronics boxes, two new cryocoolers, two new vacuum pumps, and two new electric motors for the vacuum pumps. 

Here's the parts we need to fix the WAVAR: a large fan motor, a small electric motor, a magnetron, electronics box, and a wave guide.

Here's the parts we need to fix the CAMRAS: small motor, temperature sensor, blower motor, vacuum hose, seals, electronics box

Any crew going to Mars will be trained on how to fix and maintain the life support systems.  That will be their main job since flying the spacecraft will be done from Houston. 

You need a 3D printer to have your rocket engine factory on Mars.

Last edited by Dook (2017-05-07 12:12:12)

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#189 2017-05-07 12:54:44

kbd512
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Registered: 2015-01-02
Posts: 7,548

Re: Air. Shelter. Water. Food.

Dook wrote:

No one, not even people in a settlement on Mars is going to attempt to resurface a rubber seal.  They would replace it entirely and throw the old rubber seal away.

No one but people on Mars have to pay $50,000 per kilogram of whatever is shipped there.  UPS and Fedex don't make deliveries to other planets.  If I can lay some adhesive on a seal and get another year of life out of a seal that only weighs a pound using an ounce or two of the adhesive, then I just saved enough money to buy the colonists another pound of food or water.

Dook wrote:

I'm stuck on this bracket nonsense?  Then explain all the important things you are going to make with a 3D printer on Mars.  Still waiting...

I don't have to "make" entire electronics modules, module enclosures, or anything else there when I can extend the life of what I already paid to have shipped there.  I'm not opening a life support equipment factory.  I only have to repair things there using less material and less weight than the thousands of parts that could potentially break in or on a spacecraft of any kind.  The alternative is the grand opening of a RadioShack, and Home Depot on Mars.

Dook wrote:

Do I still want to use lead-acid batteries?  Yes.  Do you still want to risk the entire spacecraft and crew lives by shipping multiple lithium-ion batteries?

If the batteries the colonists depend on only have half the energy storage capacity required to make it through the night until the next morning comes along and the PV panels start delivering electricity again, are they going to hold their breath or learn to do without something else important like thermal control, food, or water because Rocket A is only capable of delivering Payload tonnage B?

It'd be nice to use the Marscat for more than a couple hours per day, too.

Using Lead-acid batteries, the battery tonnage you're looking at just to power WAVAR would be enough to ship a nuclear reactor, never mind the batteries required by the rovers and life support equipment.

Dook wrote:

ISS uses lots of lithium-ion batteries and there have been no fires?  There are video's on the internet of people's phones catching fire.  It's rare but it happens in lithium-ion batteries much more than lead-acid batteries.

Spacecraft batteries are better built than the batteries in Samsung's cell phones.

Dook wrote:

Properly designed lead-acid batteries won't short either?  Vibration from launch, aero-capture, parachute deployment, and landing could cause a battery to short.  You would have to have batteries powering the Mars Hab but the batteries in the rover or Marscat wouldn't have to be powered.  You could install the acid plates on Mars and add water.

Lead-acid batteries are vibration and G-force tested.  East Penn Manufacturing's batteries can pass a 2.2 million cycle +5G/-5G test on their Lead-acid batteries.  If you ran that same test on any spacecraft made to date, it'd be in a million pieces in a matter of seconds.

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#190 2017-05-07 14:25:07

Terraformer
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From: Ceres
Registered: 2007-08-27
Posts: 3,826
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Re: Air. Shelter. Water. Food.

Wouldn't Nickel-Iron batteries make more sense for Mars? Lower density, but far more tolerant of abuse - and you can probably fabricate most, if not all, of the battery on Mars (still waiting for Open Source Ecology do develop plans for one...), so the mass is less of an issue.


Use what is abundant and build to last

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#191 2017-05-07 14:38:11

Oldfart1939
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Registered: 2016-11-26
Posts: 2,414

Re: Air. Shelter. Water. Food.

I use lots of battery powered lawn tools: lawnmower and weed eater. Also a chain saw. All are powered by Lithium ion batteries. And no, I haven't burned my housed down yet. Conversely, I can mow my entire lawn on a single charge of the E-Go 56 V battery.

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#192 2017-05-07 15:02:07

Dook
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From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

kbd512 wrote:
Dook wrote:

No one, not even people in a settlement on Mars is going to attempt to resurface a rubber seal.  They would replace it entirely and throw the old rubber seal away.

No one but people on Mars have to pay $50,000 per kilogram of whatever is shipped there.  UPS and Fedex don't make deliveries to other planets.  If I can lay some adhesive on a seal and get another year of life out of a seal that only weighs a pound using an ounce or two of the adhesive, then I just saved enough money to buy the colonists another pound of food or water.

Dook wrote:

I'm stuck on this bracket nonsense?  Then explain all the important things you are going to make with a 3D printer on Mars.  Still waiting...

I don't have to "make" entire electronics modules, module enclosures, or anything else there when I can extend the life of what I already paid to have shipped there.  I'm not opening a life support equipment factory.  I only have to repair things there using less material and less weight than the thousands of parts that could potentially break in or on a spacecraft of any kind.  The alternative is the grand opening of a RadioShack, and Home Depot on Mars.

Dook wrote:

Do I still want to use lead-acid batteries?  Yes.  Do you still want to risk the entire spacecraft and crew lives by shipping multiple lithium-ion batteries?

If the batteries the colonists depend on only have half the energy storage capacity required to make it through the night until the next morning comes along and the PV panels start delivering electricity again, are they going to hold their breath or learn to do without something else important like thermal control, food, or water because Rocket A is only capable of delivering Payload tonnage B?

It'd be nice to use the Marscat for more than a couple hours per day, too.

Using Lead-acid batteries, the battery tonnage you're looking at just to power WAVAR would be enough to ship a nuclear reactor, never mind the batteries required by the rovers and life support equipment.

Dook wrote:

ISS uses lots of lithium-ion batteries and there have been no fires?  There are video's on the internet of people's phones catching fire.  It's rare but it happens in lithium-ion batteries much more than lead-acid batteries.

Spacecraft batteries are better built than the batteries in Samsung's cell phones.

Dook wrote:

Properly designed lead-acid batteries won't short either?  Vibration from launch, aero-capture, parachute deployment, and landing could cause a battery to short.  You would have to have batteries powering the Mars Hab but the batteries in the rover or Marscat wouldn't have to be powered.  You could install the acid plates on Mars and add water.

Lead-acid batteries are vibration and G-force tested.  East Penn Manufacturing's batteries can pass a 2.2 million cycle +5G/-5G test on their Lead-acid batteries.  If you ran that same test on any spacecraft made to date, it'd be in a million pieces in a matter of seconds.

Lay some adhesive on a seal to get another year of life?  You're thinking of door seals, and the adhesive goes on the back, not the sealing surface.  You don't use adhesive on o-rings, they have to be smooth.  You can't use adhesive to glue them back together either, it won't last for even a minute of use.  You don't want to use adhesive on or in place of compression seals, better known as gaskets, except in an emergency because the next time you have to take that component apart, especially if it's aluminum, you are going to damage the component trying to take it apart.   

Seals and gaskets have to be replaced periodically.  There's no getting around it.  A pack of seals that would replace every seal and gasket on every piece of equipment on Mars for 100 years would weigh about 20 lbs, and the only reason it would weigh that much is because of the pressure door seals. 

Most of the time the reason you have to replace seals is because they lose their elasticity from being squeezed too often.  Synthetic rubber o-rings get hard and brittle.  Door seals get flat.  Gaskets rarely fail but have to be replaced whenever you disassemble the component. 

You think you can repair things, not replace them?  How are you going to repair a gasket, or worn bearings on vacuum pumps and electric motors, a burned out electric motor, hardened o-rings, a P sensor, a CO2 condenser, CPU's, hard drives, magnetrons, wave guides, battery acid plates, and temperature sensors?

Are the colonists going to have to hold their breath at night because their lead-acid batteries won't hold enough charge to power life support?  The RTG or reactor runs fine at night.  I think the mini-Moxie uses something like 300 watts so for 8 hours that would be 2,400 watts, about 1/5th the charge in one lead-acid battery and I'm sure the Mars Hab will have at least two or three of them, maybe more.

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#193 2017-05-07 19:45:00

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,178

Re: Air. Shelter. Water. Food.

The problem is that we just had a failure of any device or component and the mars cycle we just missed for shipping out a spare and when we fired up the spare it smoke now what are you going to do as you can not go home and there is no other means but to fix and repair what are you going to use to do this.....

What will you do if you do not know how this stuff works...

Now if we are looking at continuing resupply of duplicates of every thing with no permanent resident build up then we need not worry about things after 3 loads of these have been sent but on the first and second all bets are off...but this also is assuming we go back to the same landing site to make that choice.

As stated earlier Appolo was cancelled in just 6 flights and that was due to going different places with no real pressence remaining for the next crew to do work with. Nothing to build with as we went to so many new places....

If you ship your tools as a powder and only use it when you need that tool we can make lots more of them or other things with that same machine. You can also recycle that broken tool into more if you break the material back down for reuse. Also when we do start processing mars we will have all the feed stock for these machines in short order.

Now back to the list you seem to have P-sensor and with out knowing the circuitry we could be taking about an anologic voltage to a given pressure or we could be looking at a series of switches that are spring actuated once that pressure is achieve. The first uses what is call a piezo electric made device and the other is just a set of contacts and a spring..... Both of these devices are doable with a 3 D printer capable of each.

A dust imager is most likely a lamp and a photocell of which when there is dust in the air the amount of light will be dimmed. So the ability to make a lamp may be just one of those thing to bring while the photocell could be made by thermal ink printing the thin flim flexible cells or by the 3 D unit scaled for size as needed.

The two new accumulator o-ring kits would be of course sent by cycles to mars as these are small and can be made at low cost for shipment but when we look at all the other things that could use rubber, neoprene gaskets it would be worth sending even just 1 of the 3d machines capable of such items as we will not know when these other items will fail and we can not keep sending stuff for just in case. As we would end up with 20 of the accumilators kits and no larger items to which could not be ship in time....

Now two new cryocoolers why when mars evenings already get to near co2 solid temperatures... when made like you standard freezer is we do not look for these even after 20 years of continuous run so why would these device be any different other than its over engineered to remove mass which made it fragile....The big thing with this is not the pump or the motor but the working fluid in the cooling loop as we would not be able to create that. That we would want plenty of what ever this type is on hand....I am going to make a guess and say its helium but there are other things it could be as well....As for drawing co2 into the unit directly I would go with capture as frozen co2 during the evening moving it into a chamber to which no condensing is required....

hum, two new electronics boxes am I to assume you are referring to moxie and if so why not look at a less computer driven design as most of the unit is either an on or off cycle event.. I have actually done just that with a bidirectional valve that was computer control to which installed were a could of reed switches, magnets and lactching relays plus a non latching to make it shift from one direction stopping only at the ends once sent the signal to change. Looking at the mars rovers and rad harden cicuits in use we could expect no failures and if we are sending pairs of complete machines that we can remove the circuit board from or just simply swap the machine identifying what is broken with the removed unit for later repairs we have no issues again not sending a machine capable of repairing them but it comes at the cost ofnot only doubling up but doing so even when these are still working on the next mission....

Now two new vacuum pumps are basically a piston and a oneway valve that lets air in on the down cycle and air is forced out on the upward stroke out the vent valve.. So we covered the motor and the pump is something that can be repaired by metal 3 d printing if we need to make it again.....

Waveguides are melt tubular sructures which we already know that we can do with a 3 D unit..
The magnetron after a quick bit of looking seems also something what has been worked on...
Abstract Additively manufactured anodes in a relativistic Planar Magnetron http://adsabs.harvard.edu/abs/2015APS..DPPGO8005J

Then again 3D Printer + Microwave = Spot Welder

Its looking like the semicoductor and metal 3D units have come a long ways.....

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#194 2017-05-07 20:42:39

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

SpaceNut wrote:

The problem is that we just had a failure of any device or component and the mars cycle we just missed for shipping out a spare and when we fired up the spare it smoke now what are you going to do as you can not go home and there is no other means but to fix and repair what are you going to use to do this.....

What will you do if you do not know how this stuff works...

Now if we are looking at continuing resupply of duplicates of every thing with no permanent resident build up then we need not worry about things after 3 loads of these have been sent but on the first and second all bets are off...but this also is assuming we go back to the same landing site to make that choice.

As stated earlier Appolo was cancelled in just 6 flights and that was due to going different places with no real pressence remaining for the next crew to do work with. Nothing to build with as we went to so many new places....

If you ship your tools as a powder and only use it when you need that tool we can make lots more of them or other things with that same machine. You can also recycle that broken tool into more if you break the material back down for reuse. Also when we do start processing mars we will have all the feed stock for these machines in short order.

Now back to the list you seem to have P-sensor and with out knowing the circuitry we could be taking about an anologic voltage to a given pressure or we could be looking at a series of switches that are spring actuated once that pressure is achieve. The first uses what is call a piezo electric made device and the other is just a set of contacts and a spring..... Both of these devices are doable with a 3 D printer capable of each.

A dust imager is most likely a lamp and a photocell of which when there is dust in the air the amount of light will be dimmed. So the ability to make a lamp may be just one of those thing to bring while the photocell could be made by thermal ink printing the thin flim flexible cells or by the 3 D unit scaled for size as needed.

The two new accumulator o-ring kits would be of course sent by cycles to mars as these are small and can be made at low cost for shipment but when we look at all the other things that could use rubber, neoprene gaskets it would be worth sending even just 1 of the 3d machines capable of such items as we will not know when these other items will fail and we can not keep sending stuff for just in case. As we would end up with 20 of the accumilators kits and no larger items to which could not be ship in time....

Now two new cryocoolers why when mars evenings already get to near co2 solid temperatures... when made like you standard freezer is we do not look for these even after 20 years of continuous run so why would these device be any different other than its over engineered to remove mass which made it fragile....The big thing with this is not the pump or the motor but the working fluid in the cooling loop as we would not be able to create that. That we would want plenty of what ever this type is on hand....I am going to make a guess and say its helium but there are other things it could be as well....As for drawing co2 into the unit directly I would go with capture as frozen co2 during the evening moving it into a chamber to which no condensing is required....

hum, two new electronics boxes am I to assume you are referring to moxie and if so why not look at a less computer driven design as most of the unit is either an on or off cycle event.. I have actually done just that with a bidirectional valve that was computer control to which installed were a could of reed switches, magnets and lactching relays plus a non latching to make it shift from one direction stopping only at the ends once sent the signal to change. Looking at the mars rovers and rad harden cicuits in use we could expect no failures and if we are sending pairs of complete machines that we can remove the circuit board from or just simply swap the machine identifying what is broken with the removed unit for later repairs we have no issues again not sending a machine capable of repairing them but it comes at the cost ofnot only doubling up but doing so even when these are still working on the next mission....

Now two new vacuum pumps are basically a piston and a oneway valve that lets air in on the down cycle and air is forced out on the upward stroke out the vent valve.. So we covered the motor and the pump is something that can be repaired by metal 3 d printing if we need to make it again.....

Waveguides are melt tubular sructures which we already know that we can do with a 3 D unit..
The magnetron after a quick bit of looking seems also something what has been worked on...
Abstract Additively manufactured anodes in a relativistic Planar Magnetron http://adsabs.harvard.edu/abs/2015APS..DPPGO8005J

Then again 3D Printer + Microwave = Spot Welder

Its looking like the semicoductor and metal 3D units have come a long ways.....

Electronic items have fuses or circuit breakers that almost always protect the item from burning up.  The crew will have twenty year or more supply of extra fuses, they are very lightweight, no need to attempt to make them on Mars.   

What will we do if you do not know how this stuff works?  No one goes to Mars until we know that life support works.  It will all be tested on the ground. 

No one said we would have a continuing resupply of duplicates.  What we would have is a continuing resupply of needed things that they can't make on Mars. 

As for the resident build up, your agenda is much different than my agenda.  I want a small crew of 4 so the life support needs are minimal and there is more cushion for life support equipment down time.  You want as many people as possible in the first settlement who somehow use one tiny 3D printer and Mars dirt to make a city.   

Apollo should have been cancelled.  You think a moon base would be progress, it's would be a waste.  There's nothing interesting about the moon. 

If we ship powder and only use it to make tools when we need them we can make lots more of them or other things?  What if they need a screwdriver in space to open up the Moxie cover and splice in a new wire that shorted out? 

You can also recycle a broken tool?  With a forge.  A 3D printer won't do it.  And the forge just gets you molten steel, you still have to make it into the tool shape somehow. 

So you need two different 3D printers to make one P sensor for the Moxie and how many different types of powder?  Or, you could just send a few spare P sensors already made, they would probably weigh 2 lbs each. 

You can make any complicated component if you have enough machines but it takes more than one or two or three machines to do it.

The two accumulator o-ring kits would be sent by cycles to Mars?  No, a one hundred year supply of them (probably 10 kits) would be on the first flight.  It would weigh about 1.5 lbs. 

We cannot keep sending stuff for "just in case"?  But you want to send many different types of 3D printers and different powders for "just in case".  And all of those 3D printers can't make 90% of the life support equipment components.

As for gaskets, some are fibrous material, not neoprene.  The two body sections of the vacuum pumps probably have a paper like gasket.  They weigh next to nothing, a one hundred year supply of them for every component on Mars would weigh 1 lb. 

Why the cryocoolers in the Moxie when Mars gets cold?  Someone designed it that way.

The vacuum pumps I imagined were like the blower on a hot rod engine with two internal impellers.  The impellers and the vacuum pump body could be made with a 3D printer but not the bearings or the electric motor that turns it. 

Waveguides are tubular structures that we can make with a 3D printer?  I'm going to say probably not.  They're not just tubes, they have angled metal inside that directs the microwave energy through them.  Waveguides have to be perfect inside or they will focus microwave energy and catch fire. 

A 3D printer and a microwave are a spot welder?  Huh?

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#195 2017-05-07 21:08:56

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,414

Re: Air. Shelter. Water. Food.

Waveguides would be a piece of cake for a 3-D printer and they can be (probably already ARE) printed. If the 3-D printer can "print" a complete rocket motor, nozzle and all, in addition to most of the fancy turbo pump plumbing, saying they can't be printed would be specious. I'm going to investigate this with a friend of mine from grad school who works for Varian--the guys who build ESR spectrometers (the one I used had waveguides).

I've used and subsequently disassembled/reassembled at least 20 vacuum pumps in my career as a laboratory chemist. The bearings in most of them are not very complex, just simple castings, and made from a soft bearing metal alloy; easily made by 3-D printing. This leaves the electric motors to deal with, but nothing in any of the pumps I repaired ever needed more than thorough cleaning. That's the story for rotary style pumps; now days most pumps are diaphragm based, made almost entirely of plastics and Teflon.

Last edited by Oldfart1939 (2017-05-07 21:15:10)

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#196 2017-05-07 23:19:31

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

Oldfart1939 wrote:

Waveguides would be a piece of cake for a 3-D printer and they can be (probably already ARE) printed. If the 3-D printer can "print" a complete rocket motor, nozzle and all, in addition to most of the fancy turbo pump plumbing, saying they can't be printed would be specious. I'm going to investigate this with a friend of mine from grad school who works for Varian--the guys who build ESR spectrometers (the one I used had waveguides).

I've used and subsequently disassembled/reassembled at least 20 vacuum pumps in my career as a laboratory chemist. The bearings in most of them are not very complex, just simple castings, and made from a soft bearing metal alloy; easily made by 3-D printing. This leaves the electric motors to deal with, but nothing in any of the pumps I repaired ever needed more than thorough cleaning. That's the story for rotary style pumps; now days most pumps are diaphragm based, made almost entirely of plastics and Teflon.

A 3D printer can make a waveguide?  If it can that's still only a few components of life support equipment that a 3D printer can make.

Vacuum pump bearings are made from soft bearing metal alloy?  I'm not sure what you mean but bearings are never made from soft metal, they're always steel coated with chrome.   

Vacuum pumps bearings can be made with a 3D printer?  How does the 3D printer add the chrome to the needle or ball bearings?

Last edited by Dook (2017-05-07 23:19:48)

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#197 2017-05-08 04:15:26

elderflower
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Registered: 2016-06-19
Posts: 1,262

Re: Air. Shelter. Water. Food.

Dook, Bearings for many types of machinery can be made from stuff called "White metal". The crankshaft in your car probably runs on these. It might be possible to print this type or the porous "Oilite" type. I can't see anyone printing ball and roller bearings though.

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#198 2017-05-08 07:07:21

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,836
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Re: Air. Shelter. Water. Food.

This is the song that never ends, yes it goes on and on my friend. Some people started singing it, not knowing what it was, and they'll continue singing it forever just because...

hqdefault.jpg?custom=true&w=336&h=188&stc=true&jpg444=true&jpgq=90&sp=67&sigh=UgP1Q_7QAdf9csGfq_2o46yDIho

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#199 2017-05-08 07:36:56

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Air. Shelter. Water. Food.

elderflower wrote:

Dook, Bearings for many types of machinery can be made from stuff called "White metal". The crankshaft in your car probably runs on these. It might be possible to print this type or the porous "Oilite" type. I can't see anyone printing ball and roller bearings though.

Bearings can be made from "white metal" like the bearings for a crankshaft?  Okay, so you're going to modify the vacuum pump bearings and electric motor bearings on all the equipment on Mars so they get a constant supply of lubricating oil just so you can print these types of bearings with a 3D printer? 

You can't see anyone printing ball or roller bearings?  The 3D printer could probably print the steel part but not apply the chrome coating.   

It might be possible to make oilite bearings?  It might.  I don't think they are better than needle bearings.

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#200 2017-05-08 08:04:23

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,178

Re: Air. Shelter. Water. Food.

Dook wrote:

If we ship powder and only use it to make tools when we need them we can make lots more of them or other things?  What if they need a screwdriver in space to open up the Moxie cover and splice in a new wire that shorted out?

No need as moxie is not on the space ship out going or return trips to fix..plus we are only talking about from first post....

Oldfart1939 wrote:

It's fun to speculate on what technology we can bring to the surface of the Red Planet, but this is all about "first things first."

But to induged we would not be sending the 3 D printer for use of the space ship as that would have minimal tools onboard but the likely hood of a failure in a 6month trip is nearly none....

Dook wrote:

No one said we would have a continuing resupply of duplicates.

So you are landing at the same site each time?

Dook wrote:

What we would have is a continuing resupply of needed things that they can't make on Mars.

So when do you know you need it?
Can you survive until it gets there?
Whats the amount of backup when failure occurs, remembering that its a long time between resupplies?

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