I have a serious hard time to print out working gears for the truggy.

(gillis haasnoot) #1

I have a serious hard time to print out working gears for the truggy. The issue is not so much the printing itself, but the fact that the gears have too much friction. Nylon, petg and even PC. They all come out the same, but with the same issue. I tried already lots of different print settings (cura) but it does not help. Once you assemble a differential it is already hard to rotate them by hand. Grease won’t help either. And nylon does not wear in. Petg just breaks after a few seconds.
I am printing with a 0.4 nozzle. Do I need a higher resolution to succeed maybe?
Ányway I would like to know if there are some metal gears available somewhere. Anyone knows?

(Brandon Cramer) #2

Me personally, I would just switch to all metal drive train. Save yourself the headache.

(Klaus Daume) #3

Back then I printed my 3 differentials with ABS at 0.08mm resolution and did an acetone vapor bath to smooth them and harden them at the same time. Also I used a silicone based fat. Right after assembly they were really really hard to turn so I ran the motor/ESC at 35% max for the first two batteries. After that they ran super smooth. Later on I reprinted the gears with trimmer line (the first ones didn’t break, I just wanted to try different), printed at 0.06mm. I had a very hard time printing them due to bad retract abilities of the material. Ended up printing every gear with a single print and had to remove the strings with a hot air gun and a scalpel. At the very end, both materials worked well for me but they took a lot of post processing.

(gillis haasnoot) #4

@bcrazycramer yeah. Are there differentials out there with the same dimensions ?