While waiting for a closing date on my new place… Moving along to set something up to finally test some gear system and gears etc. Of course of the plastic variety. There are a cycloidal (waiting for bearings) and a worm gear setup in the works. The Worm gear setup is inspired by the 2020 season to get a non back driver climber (we had some trouble mechanically stopping it and finally did it with a solenoid.
This was to see if it can be designed and printed and the initial tests were promising even though the final product will have a smaller modulus.
The idea is to have the gearbox to be tested drive through a belt a gearbox that easily back drives and has a CIM motor. Through current control that “back driven” gearbox will assert an adjustable load at the to be tested gearbox. In the initial phase the “load gearbox” will be tested too. Limit switches will get activated by the belt so the arduino controlling it can reverse the setup so in effect its going to be a war of tug back and forth between the 2 gear boxes
I am going for a conventional setup for the “load box” for now as it can answer how well do gears hold up. I am not going to use a continuous belt but rather a setup similar to a 3d printer with an open ended belt (But HTD 5) That also wil lallow me to mount a fish scale (I got one up to 880lb and no I am not intending to put 880 lb in a htd 5 belt lol ) between the ends to get the settings dialed in and establish a current to power ratio.
So here is what printed today on the Load gearbox
Box and Lid
With the gears in it and bearings
A look at the 21 tooth HTD 5 pulley that will be the output underneath gear of the 2nd stage
give it a little push to see it spins freely - it does
With Lid in place
You can see the 2 holes on the side to take some 1/2 in square stock which I will use to mount it too.
Some technical specs on this one.
1st stage 19 to 71 1.125mm modulus.
2nd stage 19 to 71 1. 375 mm modulus
Output 21 tooth pulley.(1.312 in dia or almost 0.66 in radius)
All gears are 16mm wide double helical (herring bone).
Material HIPS (as its cheap). Gears printed on my predator with a .6 Nozzle the rest on my Chiron with a .8
At optimal - 27 amp a Cim puts out 4 inlb torque so that means the pulley should lift close to 100 lb Or close to a robot at almost 40 amps. Now this is not intended to be a robot lifter. Its intended to test potential robot lifters and other gear boxes. The teeth IMO are a little on the small side but I never pulled a tooth or broke a 3dp gear yet and its time I do. How else is one to discover what the limits are and where they are.
Will report as a jug allong