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Old 07-15-2019, 02:13 AM
  #5  
andreas78
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Join Date: Jun 2010
Posts: 58
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I have some experience with different materials, too. Tim's 1st post is a good summery already. I've never used PLA, due to its lack of temperature resistance. I printed parts with ABS, but most of the time I use PET-G. PET-G is good for gear covers, cable organizers and so on.
However, what I wanted to share is my experience with Polyamid (Nylon) materials.

Alloy 910 from Taulman 3D:
I printed quite a few things with that material and I actually plain love it. I don't think it is pure nylon (hence the 'alloy'). It is actually quite easy to print, but you need to prepare the material (drying).
What's it like?
- very nice surface
- very good layer adhesion, far better than ABS and much better than PET-G
- medium stiffness, get's softer as it absorbs some water over time.
- ductile, very hard to actually break, it rather bends. I wouldn't even hesitate to print some arms, they might be a bit soft though. I test printed a wheel, too, I think it would hold, but it needs some post processing, because the wheels never run perfectly true.
- should be possible to dye with some special dyes for Polyamid
- warps just a little bit, not too bad at all, print bed adhesion is good.

How I print it:
- mostly as recommended by Taulman
- print surface is a slightly grinded carbon plate, but FR4 PCB material would work too, I'm sure.
- using PVA glue for better adhesion, that is water mixed 1:1 with wood glue.
- heated bed @65C (sorry my friends from the US, I'm from Europe ;-)

Preparation:
- I usually dry it up to 8 hours or overnight in my drying device. I use a round food dehydrator. I cut out some of its trays, than a roll of material fits in easily. After that, it is good for up to 3-5days, than it has to be dried again.


The second nylon material is very interesting. It is Nylon combined with glas fibers manufactured by EUMakers (based in Italy, I think).
This material is interesting, because it is more like the polyamid used in real production kits, that is, it is reinforced with some fibers. Carbon fibers are available as well, but I've never used it.

What's it like?
- quite a bit stiffer than Alloy 910 (as expected)
- it is a bit more brittle than Alloy 910, also as expected, but overall strength is very good, too.
- layer adhesion is similar, quite good
- adhesion to bed is actually good, I do it the same way as with Taulman's nylon.
- but it warps considerably more. In my case, because my bed is not very stiff, it actually bends the carbon plate a little, especially larger parts.
- Surface is nice, layers can hardly be seen due to the fact that the surface has a mate finish caused by the glas fibers.


How I print it:
- see Taulman 3D, a bit higher temperature and you have to fiddle around with the extrusion factor.

Preparation:
- that's actually the downside, it really has to be dried for at least 8 hours at about 70-80C. I had the feeling my dehydrator is not hot enough, so I use an old oven. Freshly dried it prints nicely, but that degrades quickly after 48hours.
- you probably need at least a steel nozzle or even better a hardened steel nozzle, because the material is abrasive.

I printed gearboxes, gear covers and sideguards with this material and it is nice, but it takes time to prepare everything.

Andreas
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