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#251 2021-04-14 17:37:42

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

The local 3D printer meeting is in progress (virtual meeting on Gather.town)

One of the attendees just got this printer...

https://www.kickstarter.com/projects/3d … dprintmill

Pledge HK$ 325 or more
Just The Belt - Creality 3DPrintMill
Only $41?
By popular request from all the skilled hardware hackers in the community- just the print belt Creality has chosen to use on the 3DPrintMill. We'd love to see what you make with it.

This printer prints onto a moving belt so it can be used to print long objects such as a sword.

The link above shows several versions of the printer.  The presenter showed successful prints and an interesting failure, where the print head grabbed the object and dragged it a bit to the side, so the object was skewed to one side.  That kind of failure happens with regular X-Y-Z printers as well.

The text copied above appears to be from a side bar about a replacement belt for the printer.

(th)

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#252 2021-06-13 10:45:07

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

Here's another report of 3D Printing for housing ...

https://www.yahoo.com/news/habitat-huma … 00308.html

Source: Habitat for Humanity Central Arizona
Read the original article on Business Insider

The project is using German equipment and American workers.

The Yahoo version of the story includes a number of photograpns.

My initial impression is there are at least some walls that are printed with air space between them, which should be helpful for temperature control in Arizona, as well as for building strength. 

A nice additional touch would be foam insulation between the walls, but that expense might not be necessary in Arizona.

***
For Mars, I would see this construction technique as useful inside larger pressurized spaces, such as inside volcano tubes if there are any.

It would seem (to me at least) inappropriate for habitats on the surface directly exposed to the environment.

(th)

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#253 2021-06-13 20:34:02

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 26,747

Re: 3D Printers

Finally  for humanity article of which we have talked about its use on mars and on the moon but the issue for either is not only the material . I see that its no longer solid walled but more like a common construction with a gap to allow for pipes and electrical to go into....

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#254 2021-07-04 06:44:28

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 4,782

Re: 3D Printers

First Fully Reusable Rocket That Can Be Entirely 3D-Printed In 60 Days
https://twitter.com/TheMarsSociety/stat … 3582586887

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#255 2021-09-08 18:31:42

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

This post is coming to the forum from a Virtual/Hybrid 3D Printer meeting.  The local group has returned to the regular meeting space, fully masked up, while the virtual attendees connect from their respective homes.

This particular group has never had a formal agenda .... it thrives on challenges presented by attendees, and exchange of news between attendees.  The view I am watching is of a 3D printer brought back to life from a near-death (ie, junk heap) experience.  There was some abrasion on a wire bundle, and the previous owner did not have the background or patience to attempt repair.

The meeting leader has both, but it ** still ** took many months for the printer to return to full operation, which I am privileged to witness thanks to the services of gather.town.  Gather.town is a service like Zoom, but designed for very large corporate meetings.  We are operating at the lowest possible level, so the service is free.

(th)

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#256 2021-09-10 11:10:08

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

This post is intended as an update on 3D Printing advances, and not necessarily an endorsement of the vendor ... however, I am a shop holder, so receive these updates...

Shapeways Offers Stainless Steel 17-4 PH for Metal 3D Printing

Metal 3D printing continues to trend upward at Shapeways, bolstered by continued expansion in advanced metal powders and technology. Stainless Steel 17-4 PH (natural finish) is a new offering, allowing Shapeways customers to continue innovating and designing like never before—but with the ability to create strong metal geometries that are also even more lightweight.

(th)

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#257 2021-09-15 16:09:13

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 4,782

Re: 3D Printers

Oldest City in the Netherlands Boasts the World's Longest 3D Printed Concrete Bike Bridge
https://www.autoevolution.com/news/olde … 69117.html

World's Longest 3D Printed Concrete Bridge Unveiled in Nijmegen
https://3dprintingindustry.com/news/wor … en-195951/

Dentists and Teeth
https://www.news.com.au/best-of/money/3 … 4b717151fd

Another Bridge in China, 3D-printed polymer bridge has been unveiled in Yima River Park, Longquanyi District, Chengdu, Southwest China's Sichuan
https://www.globaltimes.cn/page/202109/1233465.shtml

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#258 2021-09-23 07:17:39

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

https://www.yahoo.com/news/ready-3d-pri … 00788.html


Are you ready for a 3D-printed house? They’re cheaper, stronger and long-lasting, developers say
David Lyons, South Florida Sun Sentinel
Wed, September 22, 2021 11:07 AM
TALLAHASSEE, Fla. — The three-bedroom, two-bath home has a corduroy-patterned exterior, rounded corners — and a cement pour that oozed from an industrial-sized toothpaste tube. And most intriguing of all, it comes from a 3D printer.

When the house is finished around November, Kyndra and James Light, a husband-wife development team, will be asking between $175,000 and $225,000 for the 1,440-square-foot dwelling.

The printed homes are said to be quicker to make, stronger, and resistant to such Florida hazards as mold, hurricanes and flooding. And most crucial of all: They seem poised to offer affordable housing in a state where many have forgotten there can be such a thing.

“While the technology is novel ... it’s still a little bit off for them to be commonly used throughout the tri-county region for hurricane reasons and the ability to build larger structures,” Poliakoff said.

But Kyndra Light said 3D homes can arrive on a mass scale faster if builders, developers, regulators and others act in concert to make them happen.

“If we can all lock arms and walk down the Yellow Brick Road, so to speak, that is what it will take,” she said.

If designed for Mars, these structures would need to hold pressure, so will likely be cylindrical, as shown in previous posts in this topic.

(th)

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#259 2021-11-10 18:24:29

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

This post is coming to the forum from a hybrid meeting of the local 3D Printer group.

I am holding down the Gather.Town connection.  This week we have no one else, but someone could drop in at any time.

At the meeting location, we have two 3D Printers ... one in operation and the other here to resume operation after adjustments.

There are three members on site at the meeting facility.

The group leader has been holding these meetings for over 10 years, and has been recognized by Meetup for staying in operation despite the Covid restrictions.

Attendance has fluctuated over the years.  Early meetings were well attended because 3D Printers were new and there was so much to learn. Now attendees are all experienced and knowledgeable, but they attend on the chance there might be someone who needs help.

that is true this evening, I expect that whatever is keeping the printer from normal operation will be discovered and corrected.

the meetings are open to the public, and with my keeping the Gather.Town session going, we may see one or more guests from outside the local area.

While no one in the forum membership (besides me) owns a 3D Printer, I did note that in the past we had a member who did.

Perhaps a new member will bring an interest in 3D Printing, along with an interest in supporting the Mars settlement project.

(th)

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#260 2021-11-15 19:21:41

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

The story at the link below caught me by surprise ... good news for growth of 3D printing in old industry ...

https://www.yahoo.com/finance/news/3d-p … 00211.html

Another growth area is in complex parts, which would be a lot more expensive to produce using traditional manufacturing methods. This does not mean, however, that every part is cheaper with 3D printing. On the contrary, the most common parts used in the oil and gas industry will continue to be more affordable when traditionally produced. Yet, as the industry seeks ever newer ways to keep its costs low while increasing the efficiency—and lowering the carbon footprint—of its operations, demand for new, complex parts is likely to rise in the coming years.

(th)

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#261 2021-11-15 19:41:50

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 26,747

Re: 3D Printers

I think it was last nights news coverage that showed how a company was printing plastics for the medical profession to simulate and study real conditions on. The plastics were being UV cured as the layers were laid down. It allows you to practice on human models of the conditions that one might have.

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#262 2021-11-30 09:23:43

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 4,782

Re: 3D Printers

Basement 3D Printer Builds Are Too Easy. Try Building One On Mars.
https://hackaday.com/2016/10/05/basemen … e-on-mars/

Self making self growing self improving Organic Replicators? not exactly 'printed' but scientists have created the first-ever living robots that can reproduce. Made from frog cells, the computer-designed organisms, created by a US team, gather single cells inside a Pac-Man-shaped 'mouth' and release 'babies' that look and move like their parents. https://www.dailymail.co.uk/sciencetech … oduce.html

In response to any ethical concerns the public might have, the team stress Xenobots are entirely contained in a lab, are easily extinguished, and are vetted by federal, state and institutional ethics experts



Microfactory thread here
http://newmars.com/forums/viewtopic.php?id=9926

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#263 2021-12-05 16:58:42

daGeck0
Member
From: United States
Registered: 2020-11-03
Posts: 3

Re: 3D Printers

Hello, all... I'm new and this is my first post (so be gentle...)

I bought a 3D printer back in April of 2020 on Amazon.
The ANYCUBIC Chiron 3D Printer I bought isn't great at extremely fine detail, but I was able to print a neck ring I designed for a helmet-based breathing system, which is 11.25" wide.

BlF7dhV.jpg

My Chiron is a filament deposition printer (uses spools of filament). Finer details can be achieved using resin printers, but the gases and spillage need to be considered. Personally, I was more interested in creating larger parts and prototyping things, rather than making small detailed items (such as D&D miniatures and jewelry).

Other 3D Printing topics of interest to usage on Mars:

Solar Sintering (Markus Kayser) (https://www.dezeen.com/2011/06/28/the-s … us-kayser/)
Something I didn't see mentioned in this thread is "Solar Sintering". Markus Kayser has created a 3D printing device that uses the power of the sun (directly, via lensing) to melt sand into glass via a sintering process (where a laser is used to melt/fuse a powdered material to form walls at a certain height and then material is swept back over the surface and leveled to the appropriate height for the next layer. The result is that you're slowly burying the newly created object in the powder (sand in this case), as you're building it layer by layer. When done, you dig the object out of the powder and you're ready to level the powder and start your next build.

Markus Kayser's Solar Sintering project seems of particular interest to a future Mars colony if there is silica readily available in the environment and if the sunlight can be appropriately focused to achieve the same sintering effect on Mars. Much like my printer, this may not be great for objects that require high precision and detail, but may be useful for making bowls, plates... even glass bricks to allow for ambient light in housing, perhaps.

Self-Replicating Printers (https://reprap.org/wiki/RepRap)
The Rep-Rap project is a bit old at this point, but the idea behind it was to design a 3D printer that could be assembled by parts that were printable by that same 3D printer. This would allow for the creation of however many printers you might need, if you had one printer and the materials to use to print the rest. At least considering such a goal of "self-replicating" 3D printers would be a good thing, as initial people on mars will have only what they brought with them and what is already on Mars to use.

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#264 2021-12-05 17:21:31

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 26,747

Re: 3D Printers

Welcome to NewMars daGeck0, and glass is a very versatile material for use in many applications. Here is a list of older glass topics.

I think I mentioned printing with glass beads as another method to create in shapes.

Glass started by RobertDyck
Glass started by Palomar
Glass-Blowing on Mars started by Palomar
Material From Sun Visor Helmet for the windows - Material From Sun Visor Helmet

There are hundreds of topics that mention Glass but these are the ones which focus on application and creation not just where it can be used.

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#265 2021-12-22 10:54:23

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

https://www.yahoo.com/news/big-step-clo … 20529.html

Zhang and his team applied dimethylsulfoxide and various sugars to the bioink. “They have been long used in conventional cryogenic storage for cells and tissues, but their integration into a bioink design has not been done before,” said Zhang.

Over the course of the study, the researchers demonstrated that the tissues could be safely frozen for at least three months before being thawed and brought back to life. The cells in the tissues proved to be as functional and as healthy as they would have been under normal conditions.

This is a very early development in the world of bioprinting. Zhang readily admits that many more in-depth studies are needed before we’re ready to 3D print a working human organ, much less freeze one and revive it. At the very least, however, this new breakthrough will make it much easier for clinical scientists to experiment with 3D tissues and find ways to get us closer to the goal of using 3D printed organs to one day save the lives of those in need of an organ transplant.

Read more at The Daily Beast.

The article at the link above reports on (to me surprising) success in bioprinting cells in a frozen state, and then thawing them months later into viability indistinguishable from "normal" condition.

While the author of the article is careful not to speculate too far on what this might mean, there is a hint that entire organis might be printed, held until needed, and then thawed for use in a paiient.

Not constrained as the author of the article would be, I am free to speculate that an entire body might be printed up, held in frozen state until needed, and then thawed for a brain transplant.

The nanotechnology required for connecting nerve and other tissues such as blood vessels does not yet exist, to my knowledge, but there is certainly nothing (that I am aware of) that precludes development of such capabilities.

As a side note ... I try to keep up with science fiction writers to the extent I have time, but I might have missed something along these lines.  That said, I have ** not ** read anything along these lines.

There are times when ** real ** science leaves science fiction writers in the dust.

(th)

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#266 2021-12-22 20:36:06

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

Here is a bit of news about 3D printing ...

Metal 3D printing with Stainless Steel 17-PH
Stainless Steel 17-4 Razor Guard

Stainless Steel 17-PH is a unique and powerful 3D printing material that <company> offers for high-performance parts and prototypes requiring strong mechanical properties. Use of this metal is expected to continue trending upward in a wide range of industrial applications.

Learn more about:

    Why manufacturers increasingly rely on metal 3D printing.
    Why Stainless Steel 17-PH is popular for manufacturing parts like jigs and fixtures.
    How Stainless Steel 17-PH is 3D printed using Binder Jetting technology.
    Finishing and design guidelines associated with this material.

(th)

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#267 2021-12-23 05:01:46

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 2,210

Re: 3D Printers

If you can 3D print with standard polyethylene, that would be a good start.  A lot of the day to day items that we use, could be produced either partly or wholly from this single material.  PE is the easiest polymer to make.  It is produced as a result of oxygen radical catalysed polymerisation of ethylene molecules, which can be produced by our sabatier reactors.  It melts at around 110°C, making it easy to use in injection moulding of all sorts of complex shapes.  It's creep properties are well understood.  We could use this material to make polytunnels for growing food, early in the colonisation effort.  Fluid carrying pipework, tables, chairs, doors, windows, gloves, space suit helmets, even clothing could be made from this single polymer.  We could also use it as a sort of binding agent for rock particles, producing composite materials that have high compressive strength and at least passable tensile properties.  Maybe an adequate choice for load supporting members.  The fire properties of this material are not great and it isn't particularly strong.  So we will eventually replace it with other polymers.  But it is easy to make and allows us to get started with manufacturing the myriad of items that we are going to need on Mars.

The key to large scale production of PE, like so much else on Mars, is the availability of abundant and cheap energy.  With enough energy you can remake the world in any way you see fit.

Last edited by Calliban (2021-12-23 05:11:54)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#268 2021-12-23 07:19:11

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

For Calliban re #267

SearchTerm:3D printer feed stock question - how does standard polyethylene perform in 3D printing
SearchTerm:polyethylene question of suitability for 3D printing

This is a question I cannot answer (despite being exposed to 3D printers and printing for years) so I'm creating this post to note the opportunity for study.

We have a new member (daGeck0) who also owns a 3D Printer, and just (recently) started working with the tool for his helmet project.

In time, (hopefully) this forum will include more members who are experienced in and knowledgable of 3D Printing.

What I ** can ** do is to bring up the question at the next regularly scheduled meeting of the local 3D Printer group. There are members who (I think) would find the question worth discussion.  The local area includes a company that makes 3D printer ribbon/filament for the commercial market.  They started out making 3D Printers and found that the filament they made in house was popular, so they transitioned to that product line.  Obviously, they would be using the optimum material for the markets they serve, but what the actual chemicals are has not registered with me.

(th)

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#269 2022-01-02 07:07:31

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 4,782

Re: 3D Printers

More more industry news on printed constructions, building homes and 3-d printed medical device

3D-printed plastic knee brace gives relief for the elderly
https://www.canplastics.com/features/3d … e-elderly/

'Called the X-Brace, the device became available on the market earlier this month. And putting it in a language that we can all understand, the researches involved describe the brace as resembling the knee brace used by Batman in The Dark Knight Rises.'



3D Printed Blood Plasma Can Speed Up Wound Healing
https://www.designnews.com/3dp/3d-print … nd-healing


Nexa3D and Henkel strikes materials development agreement
https://www.medicalplasticsnews.com/new … agreement/

Habitat for Humanity Deploys First 3D Printed Home
https://www.extremetech.com/extreme/330 … inted-home

Habitat for Humanity partnered with Alquist to build the 1200-square-foot house in Williamsburg, VA. Alquist, a large-scale 3D printing company, aims to make home ownership more accessible across demographics using advanced, environmentally-friendly building techniques. Not only does the company’s strategy reduce build time, but its 3D printed concrete homes are said to boast longer life expectancies than traditional wood-framed structures. Concrete walls also stand up well against tornadoes and hurricanes and help to reduce homeowners’ energy bills, as they offer better insulation than wood and drywall.



World First: 3D-Printing Technique Can Produce Bioresorbable, Micro-Scale Medical Implants
https://www.designnews.com/3dp/world-fi … l-implants

NASA Could Soon Start 3D-Printing Human Organs In Space
https://wonderfulengineering.com/nasa-c … -in-space/

Last edited by Mars_B4_Moon (2022-01-02 07:10:05)

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#270 2022-01-02 09:45:17

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 26,747

Re: 3D Printers

3d concrete building saves the time for custom form setup form creation of the blue print to filling it for a one off design use unless its real generic.

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#271 2022-01-02 11:24:31

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 2,210

Re: 3D Printers

It takes 24-48h for concrete to set and after about 7 days it has 70% of its fully cured strength.  So you could build structures by 3D printing of concrete shells relatively quickly.  The only problem on Mars is that concrete will freeze before it sets.  We could solve this problem by building concrete structures under a lightweight polyethylene covered frame at ambient Martian pressure and fill it with a mixture of Martian air and water vapour.  Blow warmish air under the canopy and keep the concrete at about 5°C until a few days after completion.  Nuclear waste heat will do this job.  The Martian atmosphere has sufficient pressure at low altitudes to prevent boiling of water in concrete at temperatures of 5°C.  But you would need to fill the enclosure with water vapour to suppress evaporation.

A parabolic dome would be one of the easiest structures to 3D print from concrete.  We print a thin shell under the polyethylene tent, cover it in about 3m of regolith and then pressurise to 5psi.  We could simply inflate the tent to a modest pressure and spray the concrete on the inside.  You wont need any formwork that way.  Successive layers will build up a shell.  Depends on whether you want to reuse the polythene or not.  But this is probably the quickest and easiest way to build a shell that can become a pressurised structure.

Another option is to have two polyethylene inflatable bubbles, one inside the other.  The inside one is inflated to a higher pressure than the outside bubble.  Concrete (or wet regolith) is sprayed onto the outside of the inner bubble.  After it dries, the outer bubble is depressurised and removed.  The inner bubble can be left in place providing a gas impermeable seal.  Or it can be peeled off the inner surface, leaving a parabolic shell of dried cement.  Conveyor belts can then be used to dump regolith onto the dome, which is then compressed by running trucks over it.  The outer bubble can be fully reusable.  We could make that one out of translucent silica aerogel to keep the concrete warm as it dries.  The inner one would be standard polyethylene, which can be produced from ethylene that can be produced using the same chemical reactor than manufactures methane.

Nubian vaults are another masonry structure that doesn't need formwork.  We may even be able to form an effective cement from wetted Martian fines.  The Martian regolith is so basic that it's chemical composition isn't too different from portland cement.  We need 3D printers with wheels, that can extrude wetted Martian regolith into sausages, which are then compressed onto structures.  This sort of structure has compressive strength but not tensile strength.  You need to heap overburden over the top before you can pressurise.  I wonder if a more effective approach would be to spray a cement mixture or fling lumps of it onto the surface using a rotating brush of some kind.  I am thinking out loud.  I definitely need to start using Imgur to develop my ideas.

Last edited by Calliban (2022-01-02 12:04:15)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#272 2022-01-02 19:15:48

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 2,210

Re: 3D Printers

Sprayed concrete - this is what I had in mind for habitat creation in the post above.  Inflate a polyethylene sheet to provide a parabolic dome and then spray the concrete (or even mud) onto the outside of it.
https://www.concretecentre.com/Specific … crete.aspx

Start at the bottom and build up layers of concrete, letting the layers partially dry before applying new ones.  When it is finished, cover the whole structure with regolith and pressurise.  A cheap way of building habitable space of Mars.  You can reuse the polyethylene over and over, as the only materials needed are wetted resolution, dry resolution for overburden and a layer of paint to fill small cracks on the inside.  It should be possible to vacuum plate the inside with a thin layer of aluminium.  Or we could paint it with linseed oil or something similar.


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#273 2022-01-02 19:26:58

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

Calliban .... Thanks for continuing development of this line of thought!

Since this is the 3D topic, I am assuming it is feasible to design a system to lay material as you described ....

I've not heard of a 3D printer dome attempted on Earth, but it should be quite feasible.

(th)

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#274 2022-01-02 19:32:21

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 26,747

Re: 3D Printers

The issue is the dome support while drying. If you can use an inflatable dome with a bubble of air inside the protection one can pause to allow for a given level of hardening before going on as the structure is created from the ground up. The pressure inside of the dome shape would hold the concrete in place while it hardens. Once it is the next layers can be applied and still keep the shape as the hard are is no longer pushing on it.

We have talked about another version of the inflatable which had the concrete embedded into the weave so that all you needed is to add water inside the same tent we would use for the 3d versions.

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#275 2022-01-02 20:35:26

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 11,986

Re: 3D Printers

For SpaceNut re #274

What I am about to report is for plastic 3D Printing, so it may not apply to laying concrete, as you were discussing in #274.

However, for plastic structures, it is possible to plan your structures to lay plastic ribbon as much as 45 degrees of incline.

The reason this works is that the plastic bead dries (solidifies) rapidly.  The bead is heated in a nozzle so it can be extruded, and it begins to cool and solidify almost instantly after it is extruded and laid on the surface under construction.

This post is not intended to disagree with the caution you have identified.  It does show that if the bead to be laid solidifies rapidly, then it is not necessary to have a support structure.

In the times when cathedrals were under construction before the modern age, a way was found to build a dome of brick, without using a wooden support structure. The architect used a method of laying bricks involving use of a method of sighting along a line to lay each brick. This is documented in a video that was broadcast a couple of years ago.

The point I'm making is that a dome can be constructed without a support structure.

In the case of construction of such a dome on Mars, I would imagine it could be done without pressurization.

If you are curious about the construction technique, you should be able to find it by asking Google for Italian Cathedral Dome built without scaffolding.

(th)

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