GoPiGears - Gear Train / Grabber Arm 3D Print

GoPiGo
1

I have 3D printed the STL file from here (Section 2)

https://studio.dexterindustries.com/cwists/preview/1590-lesson-5-designing-with-gearsx

But the design isn’t working for me. I don’t understand the following:

  • The hole in the Servo grabber arm is too small for the round centre of the servo arm. I managed to file this out so the cut down plastic piece from the servo (bought from Dexter) fits in.
  • Why is there a hexagonal hole on the side of the free moving arm? I would expect a 3.5 mm hole (which is approx the diameter needed for all the GoPiGo3 bolts). Also I would expect a recess underneath for the bolt head to fit in. Using a large non-GoPiGo nut in the Hex hole and a larger bolt and washer, the head of the bolt stopped the Printed Cap from clipping onto the Servo.
  • ie. Why isn’t it designed for the standard GoPiGo3 bolts?

Any pointers? I have no 3D print experience, but I will aim to adjust the STL file so it works with the nuts and bolts that are available with GoPiGo. Is FreeCad the right way to go?

1 Like
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Unfortunately, we haven’t spent time working on these gears, so they can as alien to you as they are to us.

May I suggest you redirecting these questions to the guy that designed those? You can leave your comments on that Studio tutorial - it’s pretty standard and you should get a reply from him. Or you can find him on Twitter @ MrEricksClass .

Just for my curiosity, what printer are you using and what’s the layer’s height?

Thank you!