Advice on a 3D printer for manufacturing limbs

[amysouster]

Hi, I’m new to 3D printing and am a volunteer in an amputee charity in Bolivia. We currently have had an Evolution 2nd Gen 3Dstuffmaker bought for our clinic with the aim to be able to make prosthetic hands for low income amputees in Bolivia. However…this printer is not really functioning as well as we’d like. If we try to print more than one part of a finger at a time it is really poor quality, the fan is inefficient, it will only use one type of material and fails regularly. We’re not sure if the altitude is partly responsible (we are 3600m above sea level). So I have a few questions if anyone can help:-

1) Would altitude affect print quality? Is there any recommendations as a way round this?

2) Would there be a better printer we could look into purchasing for this use at this altitude? We have a budget of between $500-$1000 to purchase a second one.

3) Any opinions on the Evolution range?

4) Any opinions on the Wanhoa range?

Thanks so much for your help.

[Thought3D]

Hi Amy,

Great project !!

We make use of Wanhao printers and they have been quite reliable. We have used the Wanhao 4s and the 4x.

If you are interested we have product that could further help you with your printing but I wont write about it here for the risk of being called a spammer

If you are interested get in touch with me at keith@thought3d.com. We would be more than happy to support this cause!!

Best of Luck and happy printing.

Keith M

[3dprintingguy]

Hi Amy, I dont think altitude would affect quality (in basic terms, 3d printing is melting plastic and depositing it in the cartesian plane) but im happy to be corrected, with your budget I would look at some of the flashforge and makerbot clones or you could look at the prusa i3s

[st3f]

I can speak about the Wanhao i3 as I use it nearly every day for more than a year. They are very reliable machines if configured properly, you need to install mods also (parts you print to improve print quality / reliability, you will find a lot on thingiverse) and know about slicers. Depending on their size and geometry, each model you print will require slightly different settings, so being knowledgeable about slicers is mandatory. I don’t think altitude will have any impact.

[amysouster]

Thanks for your reply, will have a look.

[amysouster]

Thanks for your reply, great that’s really useful to know as we will be using it a lot. Once it is set up will it require a knowledgeable user or could it be operated by most people once its been set up by a knowledgeable user?

[amysouster]

Keith, great! I’ve emailed you. Thanks.

[st3f]

Depends on the type of pieces. If you’re doing more or less the same kind of pieces (same geometry / size, infill etc) then an initial setup will be enough.

[amysouster]

Excellent news. As all volunteers come and go so that is great to know. Thanks.

[jandcando]

What material does it only print in? I’m going to guess it is PLA.

The altitude shouldn’t affect the print in any way that I can think of. Is it really humid where you live? If it is, the PLA can absorb the moisture from the air and that can affect print quality as the hot end vaporizes the water contained in the plastic while it extrudes.

As for getting a new printer, I would suggest getting a Prusa i3 kit. The Prusa i3 has the same build volume as the printer you currently have, and it is much more flexible and accessible to upgrades and such. Another plus is that there is no company-specific software associated with it. Just grab Cura or Slic3r to do the slicing, and move the generated gcode files directly to your machine!

[jandcando]

Accidental double post, disregard this comment.

[amysouster]

Thanks for your help. Yes it prints in PLA only and we wanted to use more flexible material for a more realistic finish. It is really dry here in general but if a lot of people are in the office I guess it could get humid. Always feels cold though.

I will look into the Prusa i3 especially if it has easy set up. Thanks.

[jandcando]

I would not suggest printing in PLA if you want your parts to not break when used on a daily basis. If you want a more flexible material that is also really tough, I would suggest printing in Taulman Alloy 910 Nylon. It is much more rigid than normal nylon, but flexible enough to not break when bent like PLA. It prints at 245 degrees C, so it should work with most hotends, but double check yours to be sure. Here is a video with strength tests of the material so you can get a better idea of how it behaves: LINK. I feel like this material would much better suit your purposes.

[amysouster]

Thanks for the info and the link, that looks like it would be better. The PLA is not really working for us but the problem is the Evolution 3D stuffmaker says it only prints PLA so would it support this Nylon material? (Your talking to a newbie so forgive my poor knowledge). Does this material come in other colours or is it paintable (to look like a hand)? I will ask the manufacturer about this material too. Thanks.

[jandcando]

As long as your printer’s hot end can reach 245 degrees C, it should really be able to print nylon. But if it says that it can only print PLA, they may be using a super weak heater in your printer’s hot end that can only manage PLA temperatures, which are relatively low.

As far as I can tell, it only comes in “natural” color (un-dyed). I’ve never tried to paint this material, as my hub specializes in mechanical replacement parts, so I have no idea how easy/hard it is to paint it. I’m sure it can’t be that hard, honestly.

[amysouster]

I checked with the manufacturer, our printer will not print hot enough for this material. I assume the other printers suggested in this thread will though so that might be the answer. Thanks.

[Thought3D]

Great will send you details shortly

[advanced]

1. Altitude should not affect print quality. However high humidity will affect your plastic. In that case, you would need to store the plastic in an airtight container filled with silicone crystals or (my current favourite) kitty litter crystals. Mounting a simple hygrometer will allow you to see what the humidity in the container is. You can buy a hygrometer from good pet stores who stock terrarium supplies, along with the kitty litter :).

2 & 4. I can heartily recommend the Wanhao I3 as an excellent printer at extremely low cost. It comes standard with all the upgrades you’d have to pay for and fit yourself on most other Prusa I3-based printers.

This is a fantastic project - do you currently have any of your designs for prosthetics shared anywhere?

[amysouster]

Thanks so much for the advice. We have a airtight plastic container so will invest in kitty litter and give that a go.

That’s great for the Wanhao there is a newer model 6 out so we might look further into purchasing one of these.

We are just starting out so have only produced 3 functional hands so far and we are using the flexihand model so cant take the credit for revolutionising anything (unfortunately). Do you have a suggestion of a forum/place we could start sharing our work?

Thanks.