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#101 2017-05-04 09:38:57

kbd512
Administrator
Registered: 2015-01-02
Posts: 5,875

Re: Air. Shelter. Water. Food.

Antius,

Thanks for the info.  It just dawned on me why NASA has a requirement for a continuous output of at least 40kWe for 4 to 6 astronauts.  They must want to test their ability to grow food on Mars.  There's no other equipment they use in their DRM that requires that kind of power for that number of people in as little pressurized volume as they illustrate in their presentations.  That has to be what they're trying to do.

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#102 2017-05-04 09:47:26

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

Re: Air. Shelter. Water. Food.

louis wrote:

I agree we'll start with water extraction from the atmosphere - much more dependable and it can be commenced prior to the human landing.

But why would you stop at oxygen, water and farming? 

Why wouldn't you rapidly develop an industrial infrastructure using robots, automated machines and 3D printers? Per capita energy is certainly not an issue.  The early settlement will have available many times more energy per capita than is available in human communities on Earth.

Why wouldn't you use small "rocket hoppers" for exploration of the area around your landing point?  Why wouldn't robot rovers travel to areas of interest and bring back samples (maybe under human remote control)? 

I don't think these things are too difficult - with the right equipment of course. 

Dook wrote:
Terraformer wrote:

To be honest, I've just been skipping over most of Dook's posts, and most of the replies to them. He's operating on completely different assumptions to everyone else, basing his posts on the assumption that in-situ resources won't be used, therefore one shouldn't plan to use them.

We will absolutely use Mars in-situ resources to make oxygen, get water from the atmosphere, and regolith to grow plants.

The first settlers won't be driving around Mars gathering blocks of salty ice or buckets of regolith to bring back to the base and attempt to process it for tiny amounts of water or sulfur or iron oxide. 

Producing steel on Mars with a small forge, or having a 3D printer, does not increase the settlements oxygen, food, or water and those are the things that limit your population level.

Why would we stop at oxygen, water, and farming?  Because it takes many machines to make one type of complicated machine.  Just having a 3D printer does nothing for you.  Just having a forge does nothing.  Even having both of those things does nothing because they can't make a Moxie or a WAVAR unit or solar panels.  So, with a tremendous amount of work and a 3D printer you might be able to make some small metal brackets but metal brackets are not oxygen, water, or food so they do nothing for your colony. 

The limits on population growth are oxygen, water, food, and then shelter.  Not metal components.  Being able to make metal parts does nothing to increase growth and if you waste launch vehicle space on 3D printers and a forge that means you take less extra food, less spare parts for life support equipment.  You increase the risk of mission failure. 

Why wouldn't we use small rocket hoppers?  Because the rocket hoppers burn oxygen.  Oxygen is life support on Mars.  They're not going to have extreme amounts of oxygen on Mars and even when their oxygen tanks are completely full they're still not going to use any of it on a hopper.  You're thinking in Earth terms where oxygen is plentiful in the air.  Try to imagine being on Mars and that your life depends on having that oxygen. 

Exploration can be done with little solar powered Spirit and Opportunity type rovers.

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#103 2017-05-04 10:06:19

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Air. Shelter. Water. Food.

louis wrote:

I agree we'll start with water extraction from the atmosphere - much more dependable and it can be commenced prior to the human landing.

But why would you stop at oxygen, water and farming? 

Why wouldn't you rapidly develop an industrial infrastructure using robots, automated machines and 3D printers? Per capita energy is certainly not an issue.  The early settlement will have available many times more energy per capita than is available in human communities on Earth.

Why wouldn't you use small "rocket hoppers" for exploration of the area around your landing point?  Why wouldn't robot rovers travel to areas of interest and bring back samples (maybe under human remote control)? 

I don't think these things are too difficult - with the right equipment of course.

These things go hand in hand.  If you want to produce water, food and air for an expanding base / colony, you need to build the infrastructure that makes that happen.  That means lots of steel, amongst other things, but mostly steel.

To get water in abundance, you need to either freeze it out of the air or inject heat into ice deposits.  Either approach is energy hungry and requires infrastructure that you have to import or build.  Importing it gets more and more expensive as the base expands.  making food is energy hungry, as we have discussed and requires pressurised facilities full of LEDs.  Oxygen is a by-product of food production, but may also be produced chemically from CO2 and water.  Again this is energy intensive and the more people you have, the more difficult it is to import the required equipment from Earth.

Insitu resource utilisation becomes more of a necessity the more people you have.  A base of 100 people could use imported equipment to meet its needs, if water and CO2 can at least be sourced from Mars.  A 'colony' of 10,000 people would need to manufacture a lot of equipment from local resources in order to be financially viable.

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#104 2017-05-04 10:08:35

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

Re: Air. Shelter. Water. Food.

Below is a list of the critical parts of life support equipment on Mars.  If one of these things break that system stops working and the backup system has to be started while the primary unit is fixed.

Tuna can: pressure door seals, electronics systems
WAVAR unit: zeolite panels, two magnetrons, two wave guides, a 6' wide metal fan, large electric fan motor, small electric motor for the rack and pinion, 20 foot wide circular rack and pinion, and a large tank. 
CO2 scrubber: plastic fan, fan motor, electronics sensors, CO2 absorbing canisters
Mini-Moxie: dust imager, vacuum pump, two accumulators, two buffer tanks, SOXE, cryocooler, P sensor, CO2 storage tank, condenser, and the electronics box.
Thin solar array, RTG, and/or nuclear reactor

Which of the above things can you make with a 3D printer and a small steel forge?  Name one.

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#105 2017-05-04 10:16:10

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Air. Shelter. Water. Food.

Dook wrote:

Below is a list of the critical parts of life support equipment on Mars.  If one of these things break that system stops working and the backup system has to be started while the primary unit is fixed.

Tuna can: pressure door seals, electronics systems
WAVAR unit: zeolite panels, two magnetrons, two wave guides, a 6' wide metal fan, large electric fan motor, small electric motor for the rack and pinion, 20 foot wide circular rack and pinion, and a large tank. 
CO2 scrubber: plastic fan, fan motor, electronics sensors, CO2 absorbing canisters
Mini-Moxie: dust imager, vacuum pump, two accumulators, two buffer tanks, SOXE, cryocooler, P sensor, CO2 storage tank, condenser, and the electronics box.
Thin solar array, RTG, and/or nuclear reactor

Which of the above things can you make with a 3D printer and a small steel forge?  Name one.

Initially, none of them.  Ultimately, all of them.  For Mars Direct type missions, the only things manufactured would be propellants and potentially water, if hydrogen is shipped from Earth.

If / when a permanent base is founded, its manufacturing capabilities will expand as a function of its size.  They will have to or else it won't grow.  It is that simple.

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#106 2017-05-04 10:53:36

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

Re: Air. Shelter. Water. Food.

Antius wrote:
Dook wrote:

Below is a list of the critical parts of life support equipment on Mars.  If one of these things break that system stops working and the backup system has to be started while the primary unit is fixed.

Tuna can: pressure door seals, electronics systems
WAVAR unit: zeolite panels, two magnetrons, two wave guides, a 6' wide metal fan, large electric fan motor, small electric motor for the rack and pinion, 20 foot wide circular rack and pinion, and a large tank. 
CO2 scrubber: plastic fan, fan motor, electronics sensors, CO2 absorbing canisters
Mini-Moxie: dust imager, vacuum pump, two accumulators, two buffer tanks, SOXE, cryocooler, P sensor, CO2 storage tank, condenser, and the electronics box.
Thin solar array, RTG, and/or nuclear reactor

Which of the above things can you make with a 3D printer and a small steel forge?  Name one.

Initially, none of them.  Ultimately, all of them.  For Mars Direct type missions, the only things manufactured would be propellants and potentially water, if hydrogen is shipped from Earth.

If / when a permanent base is founded, its manufacturing capabilities will expand as a function of its size.  They will have to or else it won't grow.  It is that simple.

Correct.  No critical life support components can be made with a forge or a 3D printer, so they are useless on Mars. 

Eventually, Mars will have it's own production and manufacturing but we're talking 500 years in the future.  That's not something the first settlement will attempt. 

The manufacturing capabilities will expand as a function of the base size?  No, growth is controlled by the amount of oxygen, water, and food that you can produce on Mars.  Just sending more people doesn't increase your life support, it decreases the available oxygen, water, and food for the colonists already there.  How would you feel if you had limited oxygen supplies, limited water, and limited food production and more people show up and bring nothing with them?

The new arriving crew would eat from the first crews available vegetables/chicken eggs and tilapia fish. 

So, what should happen is that every crew would land in it's own habitat with it's own food supply and then that second crew would build it's own buried habitat with a greenhouse over it just like the first crew did but with help from the first crew. 

Every new crew that arrives on Mars has to bring it's own life support.  It should arrive in it's own Mars Hab with two mini-Moxies built in, it's own water supply, a WAVAR unit, it's own large thin solar array, and another lander with buried habitat components.

You have to increase life support equally with population to have growth.

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#107 2017-05-04 11:30:32

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Air. Shelter. Water. Food.

Dook wrote:

Correct.  No critical life support components can be made with a forge or a 3D printer, so they are useless on Mars.

That's a rather sweeping assumption.  It would be more accurate to say that it would be difficult to produce complex components using a single 3D printer.  So it isn't something that a small crew would likely benefit from.  But it is hard to imagine that a permanent base would not begin to exploit this technology as its material needs increased.

Dook wrote:

Eventually, Mars will have it's own production and manufacturing but we're talking 500 years in the future.  That's not something the first settlement will attempt.

That depends what we are talking about building.  No one is going to try and manufacture microprocessors on Mars for a long time to come.  But for heavy and relatively simple components I fail to see why we need to wait 500 years.  Much depends upon how quickly you are assuming we establish a permanent base.  If the answer is 490 years in the future, then your estimate is probably correct.

Dook wrote:

The manufacturing capabilities will expand as a function of the base size?  No, growth is controlled by the amount of oxygen, water, and food that you can produce on Mars.  Just sending more people doesn't increase your life support, it decreases the available oxygen, water, and food for the colonists already there.  How would you feel if you had limited oxygen supplies, limited water, and limited food production and more people show up and bring nothing with them?

This argument appears to have become circular, but I'm not sure why.  You cannot expand the base beyond a certain point without being able to produce food, water, O2 and other things on Mars.  We would reach the point where we simply couldn't afford it.  Food, water and oxygen don't come out of nowhere; we need technology to make these things.  Eventually, it makes more financial sense to ship machines to Mars that can build what we need from native materials rather than ship every piece of equipment that we might conceivably need.  No one is saying that the initial expeditions will work this way.

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#108 2017-05-04 12:16:13

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,291
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Re: Air. Shelter. Water. Food.

One of the key skills necessary to live on Mars is the ability to build stuff. Not just buy stuff from a store, but actually build stuff. For example, I grow grapes in my back yard, make home-made red wine. And I was a member of a medieval recreation society, the Society for Creative Anachronism (SCA). When I was active in that club, I got a coal blacksmith's forge. I made my own armour from scrap metal, but the forge was to make knives and swords. I won't claim to be good at it, the current show "Forged in Fire" makes me think I should fire the thing up again. Those guys make Damascus look easy. At home I cook from scratch. Have made home-made soap, trying to find a recipe using things we can grow in a greenhouse.

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#109 2017-05-04 12:29:11

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

Re: Air. Shelter. Water. Food.

Antius wrote:
Dook wrote:

Correct.  No critical life support components can be made with a forge or a 3D printer, so they are useless on Mars.

That's a rather sweeping assumption.  It would be more accurate to say that it would be difficult to produce complex components using a single 3D printer.  So it isn't something that a small crew would likely benefit from.  But it is hard to imagine that a permanent base would not begin to exploit this technology as its material needs increased.

Dook wrote:

Eventually, Mars will have it's own production and manufacturing but we're talking 500 years in the future.  That's not something the first settlement will attempt.

That depends what we are talking about building.  No one is going to try and manufacture microprocessors on Mars for a long time to come.  But for heavy and relatively simple components I fail to see why we need to wait 500 years.  Much depends upon how quickly you are assuming we establish a permanent base.  If the answer is 490 years in the future, then your estimate is probably correct.

Dook wrote:

The manufacturing capabilities will expand as a function of the base size?  No, growth is controlled by the amount of oxygen, water, and food that you can produce on Mars.  Just sending more people doesn't increase your life support, it decreases the available oxygen, water, and food for the colonists already there.  How would you feel if you had limited oxygen supplies, limited water, and limited food production and more people show up and bring nothing with them?

This argument appears to have become circular, but I'm not sure why.  You cannot expand the base beyond a certain point without being able to produce food, water, O2 and other things on Mars.  We would reach the point where we simply couldn't afford it.  Food, water and oxygen don't come out of nowhere; we need technology to make these things.  Eventually, it makes more financial sense to ship machines to Mars that can build what we need from native materials rather than ship every piece of equipment that we might conceivably need.  No one is saying that the initial expeditions will work this way.


It's not an assumption.  You can't make the things you need.  You can make things that you don't need, like metal brackets. 
Please give the details on how you would use a forge or 3D printer to make any of the above listed critical life support components? 

You think that we don't need to wait 500 years before we can make heavy and simple components on Mars?  That's because to you it's important, it's status, it's being in the modern age instead of the stone age.  To people on Mars, it's a lot of work for things that don't provide oxygen, food, or water, so it's a waste of time and energy. 

How quickly do I think we will establish a permanent base?  I don't know when they will start but it should start with a crew of 4 and only grow in small groups of 4 and each new crew has to bring two Moxie's, a WAVAR unit, a thin solar array, and it's own buried habitat that they would have to build.  You can't just send people and expect the colonists already on Mars to eat less and share their food with the new people.

Eventually we need to ship the machines necessary to make the things we need on Mars?  How many machines do you think you need just to make a Moxie unit?  Let's see, you need to make thin steel, so a big forge, a steel rolling machine, and you need to gather and separate iron oxide and alloy elements somehow.  You need a welder, a milling machine, a bearing press, a drill press, a sheet metal cutting machine, a bandsaw, and all of that only gets you the Moxie case and the tanks.   

Nobody is saying the initial expeditions would have production?  No, the exploration teams that go to Mars and come home won't have any production but the settlement shouldn't either. 

Here's why, having one or two machines doesn't do anything.  You can't make a Moxie or a WAVAR unit from just one or two machines, so why have them at the first settlement? 

If you want real production you have to have many machines, you need a big forge, a steel rolling machine, a plate steel cutting machine, a bandsaw, a drill press, a welder, a wire making machine, and you need all the materials separated in containers, and all of those machines only get you steel products, not electronics or electric motors or filters or zeolite panels. 

Did you ever take wood shop or metal shop in high school?  How many machines and tools did they have?  Even with all those machines and tools could you make a Moxie or a WAVAR unit?  Nope. 

Eventually Mars should have production?  It should once the base has many greenhouses and buried shelters that provide plenty of food and oxygen and their WAVAR units are working well and they have near 100% water recycling, full water storage tanks, and plenty of excess power. 

Even then, they will need periodic resupply shipments of spare parts like acid plates for rebuilding batteries, new filters for the Moxie and WAVAR, new bearings for vacuum pumps, replacement electric motors for all the fans and rovers, magnetrons and waveguides for the microwaves, electronic motherboards, laptop computers, sensors, CO2 absorbent, womens sanitary items, and probably a hundred other things I can't think of.

Last edited by Dook (2017-05-04 12:37:36)

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#110 2017-05-04 13:31:57

Terraformer
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From: Ceres
Registered: 2007-08-27
Posts: 3,531
Website

Re: Air. Shelter. Water. Food.

Dook, it sounds like you're imagining the government paying for a Mars base for the next few centuries, until it suddenly becomes a colony...


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#111 2017-05-04 13:45:16

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Air. Shelter. Water. Food.

I agree with Robert that it's all about manufacturing on Mars (which obviously requires other aspects such as mining, refining and chemical/gas production). Dook's claims about our inability to 3D print various components needs testing. He needs to specify the particular items - then we can test that against what is already being produced.  Personally, I am amazed at what can now be produced by 3D printers. But they only part of the story. There are robot diggers, CNC machines, CAD design, automated chemical analysis and automated processes. The Mars community will be able to use electrolysis, heating etc. to purify ores.

Just about anything done in big industry can be done on a smaller scale, just as you can have a big steam locomotive or a tiny one.

Last edited by louis (2017-05-04 13:46:33)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#112 2017-05-04 14:06:11

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

Re: Air. Shelter. Water. Food.

Terraformer wrote:

Dook, it sounds like you're imagining the government paying for a Mars base for the next few centuries, until it suddenly becomes a colony...

Someone is going to pay for a colony on Mars, either the government or SpaceX or a combination of both.  I think that NASA will likely contract out to SpaceX to deliver some things to Mars using it's Heavy Falcon.   

Were you under the impression that a colony on Mars could trade with the Earth and pay for itself?  There's just no way.  Name one thing that you can produce on Mars for about one hundred times cheaper than you can make it on the Earth. 

With Mars Direct we can afford to launch resupply missions to Mars once a year and then every 15 years or so when Mars is closest we can launch a new crew of 4 in a Mars Hab with two mini-Moxies and a WAVAR for life support, food, water, and a separate launch of a new buried habitat that they would have to build to expand the base.

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#113 2017-05-04 14:20:54

Terraformer
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Website

Re: Air. Shelter. Water. Food.

Are you under the impression that Earth will be willing over the next century to pay to keep a Mars base afloat that won't even manufacture basic items for itself? No. Not going to happen. The cost of shipping to Antarctica is peanuts compared to Mars - and if it gets down to similar levels, then the space cadets will be rejoicing before loading up the freighter to establish a new colony.

Last edited by Terraformer (2017-05-04 14:21:12)


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#114 2017-05-04 14:21:06

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

Re: Air. Shelter. Water. Food.

louis wrote:

I agree with Robert that it's all about manufacturing on Mars (which obviously requires other aspects such as mining, refining and chemical/gas production). Dook's claims about our inability to 3D print various components needs testing. He needs to specify the particular items - then we can test that against what is already being produced.  Personally, I am amazed at what can now be produced by 3D printers. But they only part of the story. There are robot diggers, CNC machines, CAD design, automated chemical analysis and automated processes. The Mars community will be able to use electrolysis, heating etc. to purify ores.

Just about anything done in big industry can be done on a smaller scale, just as you can have a big steam locomotive or a tiny one.

I've specified the particular items that need to be produced many times.  Look at post 104.  You're ignoring the facts because you don't know what a 3D printer can and can't do.  You've assumed they can do way more than they really can. 

There are robot diggers?  Yeah, someone has to drive the vehicle to the spot and turn it on before it can dig.   

CNC machines mill solid metal, that's great for making metal brackets out of solid blocks of metal.  Having a bunch of metal brackets on Mars does not increase your population because people can't eat brackets or breathe them or drink them.

CAD design is fantastic for designing.  I took a CAD class in college.  On Mars they wouldn't need CAD because if they did have a 3D printer every component in every machine on Mars would already be saved as a CAD file either in the 3D printer itself or on the crews laptop computers.  The problem is that the 3D printer can only make the vent tubes for the Moxie, that's it.   

Just about anything that can be done in big industry can be done on a smaller scale?  Okay, but you need a specific machine to do different tasks.  You need a drill press, a cutting machine, a pressure roller, a welder, a forge, and having those things just get you metal components.  It doesn't get you a Moxie, or a WAVAR unit or a solar panel, or oxygen, or food, or water.

How many metal components does it take before you can add one person to a colony on Mars?  A hundred?  A thousand?  What is the new person going to breath, drink, and eat?

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#115 2017-05-04 14:24:55

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Air. Shelter. Water. Food.

Dook wrote:

Were you under the impression that a colony on Mars could trade with the Earth and pay for itself?  There's just no way.  Name one thing that you can produce on Mars for about one hundred times cheaper than you can make it on the Earth.

This is in fact a problem, one that has been brought up numerous times on this board and never satisfactorily answered.  Even under optimistic scenarios, it is difficult to foresee Earth-Mars transport costs dropping below several hundred dollars per kg.  Sending things back to Earth won't be cheap either.  What could a colony possibly sell that could pay for its very expensive imports?  Trinkets and souvenirs aren't going to do the trick.  It needs to be something that the entire world needs and will pay a bucket load of cash for.  My own pet favourite is solar power satellites.  Could we adapt O'Neill's vision to Mars?  The Martian atmosphere is thin enough that a mass driver should be able to punch through it.  Maybe we manufacture the satellites in Mars orbit and use reaction engines to ship them back to Earth orbit.  This sort of project would require enormous infrastructure investment, but as far as I can see, it is the only product that has any chance of being sold a sufficient profit and in sufficient volume to pay for Mars colonisation.

Last edited by Antius (2017-05-04 14:36:11)

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#116 2017-05-04 14:29:54

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

Re: Air. Shelter. Water. Food.

Terraformer wrote:

Are you under the impression that Earth will be willing over the next century to pay to keep a Mars base afloat that won't even manufacture basic items for itself? No. Not going to happen. The cost of shipping to Antarctica is peanuts compared to Mars - and if it gets down to similar levels, then the space cadets will be rejoicing before loading up the freighter to establish a new colony.

Am I under the impression that the Earth will be willing over the next century to pay to keep a Mars base afloat?  Are you under the impression that we would leave them to die? 

We've spent money on Hubble and it was messed up, did we just leave it? 

We spent a lot of money on Apollo, what did we get out of it? 

We spent money on the Space Shuttle and it blew up twice, yet, we still kept flying it for years and years. 

NASA hasn't stopped working.  Their budget has not been cut.   

The Mars colony will manufacture basic items for itself, they're called oxygen, water, and food.  What necessary thing are you going to make with your metal? 

The cost of shipping to Antarctica is peanuts compared to Mars?  A Mars colony is affordable and possible if you keep it simple.  If you ship 3D printers and forges and manufacturing equipment to Mars then it's not because they can't make life support equipment.

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#117 2017-05-04 14:42:39

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

Re: Air. Shelter. Water. Food.

Louis, why don't you do this, send an E-mail to a 3D printer company and ask them if their 3D printer can make any of the following components: 

Electric motor
Magnetron
Wave guide
Metal tank, unpressurized and pressurized
Electronics motherboard, a computer hard drive, computer RAM, or integrated circuits
Vacuum pump
Sensors
Condenser
Solar cell or solar array
Batteries or the acid plates in a battery

Last edited by Dook (2017-05-04 14:43:48)

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#118 2017-05-04 16:27:46

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Air. Shelter. Water. Food.

The MIT PV study looked to 100Kwe average constant for 6 people.  Seemed a lot but I think much of that  is lost in efficiency if you make methane or store your power in chemical batteries. Might be less for nuclear...but then I think it highly unlikely you can got to Mars with nuclear reactors alone. I think you will need substantial PV and probably methane as well.

kbd512 wrote:

Antius,

Thanks for the info.  It just dawned on me why NASA has a requirement for a continuous output of at least 40kWe for 4 to 6 astronauts.  They must want to test their ability to grow food on Mars.  There's no other equipment they use in their DRM that requires that kind of power for that number of people in as little pressurized volume as they illustrate in their presentations.  That has to be what they're trying to do.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#119 2017-05-04 16:41:17

kbd512
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Registered: 2015-01-02
Posts: 5,875

Re: Air. Shelter. Water. Food.

Apart from the ball bearings and shaft, our homopolar generator prototypes are 3D printed because it costs too much to have a machine shop mill the parts.  The bearings are ceramic and expensive.  The shaft is carbon steel, but could be plastic at the low speeds we're turning it at.  The permanent magnets would be nearly impossible to make on Mars.

I have no idea what you'd need a magnetron or wave guide for, unless you're still stuck on using WAVAR.  It's blatantly obvious that there's a lot more water in the ground than the atmosphere and the energy required to extract it is much lower.

Google "Voxel 8" to see 3D printed electronics.  Voxel 8 machines 3D print circuit boards, antennas, pressure transducers.  All microchips are 3D printed as is and so are thin film solar arrays.  It's possible to repair electronics using a 3D printer if the electrical connectors on the circuit board break without soldering.  The material quantities in question are tiny, so they can obviously be brought from Earth at low relative cost.  Using conductive inks with graphene added to them, circuitry can be inked onto flexible substrates, rather than hard and heavier PCB boards.

Rocket engine combustion chambers, propellant injectors, and nozzles are 3D printed, as are turbine blades in turbo pumps because machining turbine blades from billets takes weeks and printing takes hours, with almost no material waste.  Rocket engines are super high pressure pressure vessels.  If you can print rocket engine parts pressurized to hundreds of atmospheres, then you can also print low pressure metal storage tanks.  It's also possible to repair these items with 3D printers in a process analogous to welding.

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#120 2017-05-04 17:07:44

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

Re: Air. Shelter. Water. Food.

kbd512 wrote:

Apart from the ball bearings and shaft, our homopolar generator prototypes are 3D printed because it costs too much to have a machine shop mill the parts.  The bearings are ceramic and expensive.  The shaft is carbon steel, but could be plastic at the low speeds we're turning it at.  The permanent magnets would be nearly impossible to make on Mars.

I have no idea what you'd need a magnetron or wave guide for, unless you're still stuck on using WAVAR.  It's blatantly obvious that there's a lot more water in the ground than the atmosphere and the energy required to extract it is much lower.

Google "Voxel 8" to see 3D printed electronics.  Voxel 8 machines 3D print circuit boards, antennas, pressure transducers.  All microchips are 3D printed as is and so are thin film solar arrays.  It's possible to repair electronics using a 3D printer if the electrical connectors on the circuit board break without soldering.  The material quantities in question are tiny, so they can obviously be brought from Earth at low relative cost.  Using conductive inks with graphene added to them, circuitry can be inked onto flexible substrates, rather than hard and heavier PCB boards.

Rocket engine combustion chambers, propellant injectors, and nozzles are 3D printed, as are turbine blades in turbo pumps because machining turbine blades from billets takes weeks and printing takes hours, with almost no material waste.  Rocket engines are super high pressure pressure vessels.  If you can print rocket engine parts pressurized to hundreds of atmospheres, then you can also print low pressure metal storage tanks.  It's also possible to repair these items with 3D printers in a process analogous to welding.

The main component of a generator is the copper wiring.  Where are you going to get the copper from on Mars?  Are you going to wrap the copper wiring by hand? 

You need backup magnetrons and wave guides for the habitat microwave and two backups for the WAVAR unit. 

There is a lot more water in the ground than the atmosphere?  There is but it's frozen and mixed with salt, frozen CO2, and it's deep.  The atmosphere is at our base. 

The Voxel 8 is a circuit printer.  It will make chips.  The maximum size chip it can make is 100mm by 150 mm by 100 mm, so not even 1/2".  It won't make large metal components.  You and Louis keep linking me to machines that make one particular thing and you're trying to say that because it's called a 3D printer that it can make everything that any other 3D printer can make.  It doesn't work like that.  There are different kinds of 3D printers.  And instead of shipping this Voxel 8 machine to Mars we could ship a one thousand year supply of chips to Mars. 

Rocket engines can be 3D printed?  Not with a Voxel 8 they can't.  That is a different 3D printer.  They're not the same machine, they may use the same process but it takes different machines to make different things.  Where are you going to get the titanium from on Mars?

And the settlers on Mars will have too many rocket engines already sitting around in the Mars Habs that landed them there and the supply landers.

Last edited by Dook (2017-05-04 17:08:42)

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#121 2017-05-04 18:25:56

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,291
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Re: Air. Shelter. Water. Food.

Dook is obsessed with 3D printing. I think he believes the only manufacturing possible on Mars must be done that way. A 3D printer is automated, doesn't require skill. Just plug select your design, fill the hoppers, turn it on and wait for it to finish. That tells me he's never made anything. Ever fabricated anything out of wood, plastic, metal? I have. Ever operated a lathe? And I don't mean a CNC lathe, I mean a manual one. I have.

Ever designed and etched a printed circuit board by hand? I have. My first modem was a 300 baud Hayes external, but for one computer I designed a circuit board for a dial-up modem, hand etched a 2 sided board, hand drilled holes for integrated components, hand soldered everything in place. It worked: 1200 baud.

GW Johnson has pointed out some parts can be 3D printed, others cannot. Fine, we aren't restricted to 3D printing on Mars. We can use normal tools.

For an earlier computer I fabricated a back plate with a connectors for printer and serial port. I used a hand drill to cut holes for the DB25 connector, used a hack saw to cut the rough shape, then a file to finish the shape. For mounting points I used a drill, and tap-and-die set to tap threads into the steel plate. None of this was 3D printed, none was CNC, it was all done with hand tools.

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#122 2017-05-04 19:10:18

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

Re: Air. Shelter. Water. Food.

RobertDyck wrote:

Dook is obsessed with 3D printing. I think he believes the only manufacturing possible on Mars must be done that way. A 3D printer is automated, doesn't require skill. Just plug select your design, fill the hoppers, turn it on and wait for it to finish. That tells me he's never made anything. Ever fabricated anything out of wood, plastic, metal? I have. Ever operated a lathe? And I don't mean a CNC lathe, I mean a manual one. I have.

Ever designed and etched a printed circuit board by hand? I have. My first modem was a 300 baud Hayes external, but for one computer I designed a circuit board for a dial-up modem, hand etched a 2 sided board, hand drilled holes for integrated components, hand soldered everything in place. It worked: 1200 baud.

GW Johnson has pointed out some parts can be 3D printed, others cannot. Fine, we aren't restricted to 3D printing on Mars. We can use normal tools.

For an earlier computer I fabricated a back plate with a connectors for printer and serial port. I used a hand drill to cut holes for the DB25 connector, used a hack saw to cut the rough shape, then a file to finish the shape. For mounting points I used a drill, and tap-and-die set to tap threads into the steel plate. None of this was 3D printed, none was CNC, it was all done with hand tools.

You ran into the wrong dugout there buddy and don't even know it.   

Louis and KBD are obsessed with 3D printing because they think all 3D printers are the same machine.  My argument is that it's a waste of rocket fuel to send one to Mars because it can't make life support equipment. 

A 3D printer doesn't require skill, just fill the hopper?  Oh, really, hehe...  Sounds like you're the one who doesn't know about manufacturing and fabrication.  What size particle do you put in the hopper?  I'll let you look it up.       

I've never fabricated anything out of wood?  What life support equipment can you make out of wood?  None. 

Have I ever operated a lathe?  What life support equipment can you make with a lathe?  None. 

Have I ever designed, etched, and printed a circuit boards by hand?  I have people in Taiwan do that for me.   

GW Johnson said that some parts can be 3D printed, others cannot?  That's somewhat vague.  Here's the thing, everything can be made on Mars with a whole lot of machines and a whole lot of time and energy processing massive amounts of regolith to get very tiny amounts of aluminum and copper and alloys.  One 3D printer won't make any life support equipment. 

You used a soldering iron, a drill, a lathe, a hack saw, a file, a tap and die?  So, you're saying that it takes many tools to make one complicated component?

Last edited by Dook (2017-05-04 19:14:24)

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#123 2017-05-04 19:31:58

kbd512
Administrator
Registered: 2015-01-02
Posts: 5,875

Re: Air. Shelter. Water. Food.

Dook wrote:

The main component of a generator is the copper wiring.  Where are you going to get the copper from on Mars?  Are you going to wrap the copper wiring by hand?

There are no windings in homopolar generators, not even the kind we're building.  The quantity of copper required is as minimal as the ampacity of the material allows since our conductors are not solid copper discs.  Most homopolar generators generate massive amperages at low voltages, but our voltage problem has been solved by using counter-rotating segmented discs.  The prototype produces 24 times as much voltage as a solid copper disc of the same diameter using the radially segmented conductors printed onto plastic.  If the rotors had greater diameters, we could further multiply the voltage by using more segments.

Dook wrote:

You need backup magnetrons and wave guides for the habitat microwave and two backups for the WAVAR unit. 

There is a lot more water in the ground than the atmosphere?  There is but it's frozen and mixed with salt, frozen CO2, and it's deep.  The atmosphere is at our base.

The water isn't deep, else the Mars rovers wouldn't detect it when they heat the samples they collect.  They have no drills of any substantial length.  Salt water is a solution, so when you heat the water the salt remains in the regolith, but you already knew that.

Dook wrote:

The Voxel 8 is a circuit printer.  It will make chips.  The maximum size chip it can make is 100mm by 150 mm by 100 mm, so not even 1/2".  It won't make large metal components.  You and Louis keep linking me to machines that make one particular thing and you're trying to say that because it's called a 3D printer that it can make everything that any other 3D printer can make.  It doesn't work like that.  There are different kinds of 3D printers.  And instead of shipping this Voxel 8 machine to Mars we could ship a one thousand year supply of chips to Mars.

I never said a Voxel 8 machine would produce chips.  I said chips are 3D printed and Voxel 8 3D prints circuit boards, sensors, and antenna.

If you send a thousand years supply of chips to Mars, you'll have a 1000 year supply of paperweights in about five to ten years, unless you bury the chips and protect the chips from static and temperature extremes.  The GCR radiation kills chips.  GCR's have already fried some of the chips in one of our rovers.  Those were rad-hard chips, BTW.  The cost of the individual chips ranges from $100K to $1M as a function of how they're made, what they're made with, how few are made, and how extensive the testing protocols are.

Dook wrote:

Rocket engines can be 3D printed?  Not with a Voxel 8 they can't.  That is a different 3D printer.  They're not the same machine, they may use the same process but it takes different machines to make different things.  Where are you going to get the titanium from on Mars?

We don't rebuild an entire RS-25D or Merlin-1D from scratch every time we want to use it.  We repair, rebuild, or replace the few components that fail.  The failures are fairly predictable with experience and typically limited to seals and moving parts.  If we have the tools to repair or rebuild on Mars, then there's a lot less replacing that needs to be done.  If we don't have to have the exact component on hand to make the replacement with, then we have fewer types of components to maintain and deliver.  Experts back on Earth can diagnose and issue instructions for repairs by exchanging E-Mail with the colonists.

A Merlin-1D is designed for 10 flights with no maintenance or 100 flights with a bit of maintenance between firings.  If I only had to send a couple rocket engine to Mars, a couple 3D printers, and some powdered metals to repair cracks and conductive inks to replace electronics, then that really cuts down on cost and the types of inventory I have to maintain stocks of to ensure that whatever I need I have.

Dook wrote:

And the settlers on Mars will have too many rocket engines already sitting around in the Mars Habs that landed them there and the supply landers.

Given your plan to build new rocket engines to deliver every single thing that ever lands on Mars for the next 500 years or so, as you put it, that's probably true.  The rest of us here have caught on to the fact that rocket engines are typically reusable if propellant is reloaded and minor problems are fixed between uses.  I guess I'd rather send the equipment to make the small quantity of rocket fuel and replacement parts so that the landers can continue to fetch colonists and supplies from orbit.  I want to land things 5 to 10 tons at a time, use local resources, and limited manufacturing capabilities to make this an affordable endeavor.  I don't need a propellant plant the size of a building.  Something the size of a refrigerator would work just fine.

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#124 2017-05-04 19:52:36

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Air. Shelter. Water. Food.

Dook - If you really believe that I believe there's only one type of 3D printer, then that is sad...very sad.

Of course I know there are hundreds of 3D printers.  Personally I would aim to take along at least two for a first mission to Mars - one working with metal powders and one with plastics. Not that you can't combine the two processes, it's just we may well wish to operate them simultaneously and I doubt on Mission One we will be looking to make complex metal-plastic components.

As Robert points out, 3D printers are only one small but significant element of early industrial production on Mars - there will be CNC and hand operated lathers...saws...compressors...all sorts of machines.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#125 2017-05-04 20:10:57

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,291
Website

Re: Air. Shelter. Water. Food.

I had previously posted here: Should, Shouldn't, Couldn't...What we need to make on Mars...

RobertDyck wrote:

Basic appliances should be made on Mars. The Mars Homestead Project talked about the first settlers, assuming 12. Start with 3D printers and basic tools, then grow the workshop.
...
I'm thinking something similar to the following.
...
North Forge Fabrication Lab
3D Room: 3D Printer (plastics, 3 brands), Vibratory Polisher, 3D Printer (Multi-Material Resin), 3D Object Scanner (2 brands), Smoothing Station, 3D Printer (Production Grade Plastics), 3D Printer (Full Colour Sandstone), Waxing Station, MakerBot Replicator 2X (2 units)
Laser Room: CNC laser cutters - 50w, 120w, 75w (2 different brands)
Electronics Room: PC Board Pick and Place, PC Board Plotter, PC Board Prototyper, SMT Solder Oven, Environmental Shock Testing Chamber
CNC Metal Room: CNC Plasma Cutter, Knee Mill, Horizontal Band Saw, Manual Metal Lathe, Mig Welder, Abrasive Blasting Cabinet, TIG Welder, CNC Mill/Lathe
Metal Area: 12 ton Press, English Wheel, 75 Ton Ironworker, Break, Hydraulic Shear
Textile Room: Wide Format Printer, Sewing Machine, Vinyl Cutter
Paint Area: Paint Chamber
Tool Room: many hand tools, see image
500px-ToolRoom.png
They also have a CNC Wood Room, and well equipped Woodworking Room. However, Mars doesn't have trees so I don't think that will be useful on Mars.

I'm thinking many of these tools will have to be sent from Earth. But I'm hoping the heaviest can be made on Mars. Send key components, but fabricate the heaviest parts on Mars.

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