I got to work on my Shapeoko 3 for about 2-1/2 hours this evening and I got the plates mostly assembled. I had one bolt and nut that would not go together at all, so I’ll stop at the hardware store on the way home from work tomorrow and replace them.
Since I can’t leave well enough alone, I’ve already made some changes during the assembly. Change number one was using nylon locking nuts everywhere I could. I have an assortment of 5mm fasteners from my Shapeoko 1 rebuild, so I used some of those.
The other change was in the way the stepper motors are mounted. Edward designed it so that you used a button head cap screw from the front and put a nut on the back of the stepper motor flange. Unfortunately, there really isn’t enough room to get a wrench on the nuts, so it’s difficult to get them tight.
So I used socket head cap screws and flipped them around. There are only a couple of places where clearance is a problem and I’ll point them out in the photos.
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One of the first modifications was to file flats on to the stepper motor shafts. I’m a big believer that set screws on pulleys work better if there is a flat for them to engage. Just a few passes with a file is enough.
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I used a large machinist square to align the Z rails perpendicular to the bottom edge of the X axis plate. After I got both rails bolted on I checked them for parallel with my caliper. They were within .004″ top to bottom, so I called it good enough for now.
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I deviated from the plan when mounting the stepper motors. I was having issues getting a wrench on the nylon lock nuts, so I replaced the button head screws with socket head cap screws and flipped them around so the nuts were on the other side of the plates. There were a couple of clearance issues, but this mostly worked out.
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I had 30mm long SHCS so they stick out a little. 25mm screws would have been perfect.
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I had to cut two screws on the X axis plate to make them 25mm long for clearance issues. I also had to use one button head screw in the designed configuration.
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I had an issue with one of the idler bolts and nuts not fitting together, so neither are mounted at the moment so I can take the ones that work to the hardware store today.
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The Y axis plates are done.
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The Z axis plate is also done.
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That is as far as I got last night. More work will occur this afternoon and evening. I might even get it running tonight.