I can't remember how long its been since I bought all the parts for my Ox build and in that time I never noticed that the drive shafts on the Nema 23s don't have a flat side. I've got to the point of connecting everything up and placing the Ox on a 4' X 5' 18mm ply base, because the machine is 3' wide and 4' long so I could cut 2' X 3' sheets at a time. The Nema 17 has a flat side on its shaft, but the others haven't. I was wondering if this was OK to leave as is or the take them off and grind them flat. when ever I've used a grinder in the past people run for cover screaming their heads off so I would prefer the first option. Lastly, in mark's video, when he came to attach the Nema 23s to the machine he said he had already tapped the four holes in each one to accept the screws, but I found the m5 screw just slips through those holes. Is there enough room to use an M6 tap and use M6 screws instead Any one have the same problems while building their machines please let me know. Thanks.
if youre couplers have two set screws per shaft you should be okay. youll want to keep an eye on them for slip. there are various types of set screw ends. crowned, flat, pointed, cupped.... Flat and domed are least desirable for your scenario, but flat will probably hold if you have two in the coupler on the shaft. You may want to search out a pointed or crowned type if you dont want to grind anything. a machine shop should be able to put flats on the shafts for no more than $20. cant comment on the OB question.
Hello Centurian, Those NEMA23 motors are not from OpenBuilds, are they? I would make a flat side on them directly to avoid having to take the machine apart later, but just by hand and not a powertool. About the holes in the stepper motors, just use M5 nuts on top of the motors, that's how the OX is build now. The video was just an example video and some parts are outdated, but still useful. -Ronald OpenBuilds México
Hello Ronald Thanks for the reply. No, the Nema 23s came from Germany and the reason for that is the cost of them coming from US and the customs charges on top of that would have been nearly as much as the price of the Nema's themselves. I didn't buy the rails or the plates from Openbuilds either for the same reason. Everything else came from the US. I've now made a flat side on all 3 motors and was surprised how well they turned out. So the traction belt wont be slipping at any point in the future. ( The video was just an example video and some parts are outdated ) Now you tell me, when I've completed the build lol. I've stayed with the M5 bolts and put lock nuts on the back. So the Nemas should stay ridged. Michael Centurian.
Hi Michael, Asking and building at the same time , well, I thought you would have called it day yesterday. So you ground the shafts down or did it by hand, some abrasive hand tool? Hell, I would have done it with some Dremel as well. Importing stuff is a *****, NAFTA is a load of crock, tell me about it, all I buy is coming from the USA. -Ronald OpenBuilds México
If it was me, I would use the Dremel to put a small flat (just where necessary) on the shaft. Tweakie.
I had this problem with the shafts on my motors the steel could be easily filed. I placed the shaft in a vice and filed a flat onto them using the vice jaws/side of the vice as a guide to make sure they were filed square, also I filed a small grove near to the motor to begin with to have an edge to work up to - if that makes sense! I thought it was going to be a pain but only took a few mins and you'd be hard pushed to see they were hand filed.
