Solved printing issue / problem / filament issue

You need a tougher material.

http://taulman3d.com/how-to-choose.html

 

<shrug> Depends on the size of the handle and how much force it needs to be able to withstand.
I would probably start with a nylon (like Alloy910) but if it needs to withstand a lot of force it may need to be completely redesigned and/or go for a more extreme material like polycarbonate. Frankly I'd start with alloy910 and a redesign to use an embedded (metal) nut with reinforced walls to hold it.

 

That alone may help enough to get you going. A tougher material alone may as well. No clue how much force you are dealing with there

 

I have not been thrilled with any of them, but just find a reputable dealer you trust.
Someone you have bought good filament from in the past. It is a bit more difficult to get printing correctly although probably not as difficult as ABS -- but close.

 

I use Ultimaker brand ( 2.85mm so wont be using that on the robos) and polymaker polycabonate. I like it and its affordable. Their spools are NOT 1 KG.

 

a mat?

 

A raft?
Maybe. Try it without and see if you get too much bottom edge warp.
It runs hotter too so make sure you are at the right range.
260°C is about the normal for it, but some brands are a bit more and others a bit less.

 

https://www.matterhackers.com/articles/how-to-succeed-when-printing-with-polycarbonate-filament

 

on my Ultimaker I print on bare glass with glue stick, bed 110C hotend 240-260 depending on the materials. Being that hot I dont like to leave it run unattended. On other machines I do buildtak with glue stick on it and about the same temp nozzle, 80 bed, 90 if the printer can do it easily.