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Great!And definitely, don't try to bore out that worm bigger than 1.5mm. Yes, I think 1.5mm, and then sleeve the two 1.5mmshafts together as you suggest, is the way to go.Question... that shaft on your Maxon motor looks AWFULLY short, and looks like it was chopped off. Did it come that way when you bought it? How much shaft do you have to work with on the motor?How are you going to ream out the worm from 1.2mm to 1.5mm? That's about .012". I've done it by hand just with a few successively larger bits in a pin vise, using an actual reamer at the very end so you end up with a nice snug fit on the shaft.
You can use a Dremel disk, but just hold it against the pinion, while the pinion itself is gripped in some small needlenose pliers. You should be able to grind away enough of the pinion until you are almost down to the motor shaft, and then it will just break away from the shaft, leaving the shaft intact.
Next time! I have about 1.5mm and can abut against the shoulder of the motor shaft all the way to the end, all of that rotates, not just the 1.5mm part.
The 113 is a 1/16" "engraving cutter". It is completely straight (no taper), so it would make a really good reamer.Although 1/16" is about .025" bigger than 1.5mm. John, when you do this, does the worm fit snugly, but loose enough to push on by hand, or is it a loose slip fit that just slides on and off the shaft?If you're going to buy something anyway, I'd buy a #54 and #55 drill bit, and something like this:https://www.amazon.com/1-5mm-HSS-Chucking-Reamer-USA/dp/B006Q4XKE2 , a true 1.5mm chucking reamer.
0.025mm = .009" so in reality, that is a typical accurate slip fit. A 1.5mm finished hole in the worm can potentially create a pretty heavy press fit when the tube's tolerance and roundness is taken into account. Let's just say that the slip fit has not been an issue on any of the motors I have done this on. Plus, a light press only provided an opportunity for this klutz to damage a motor. Ask me how I know.
My math was messed up.I said 1/16" is about .025" bigger than 1.5mm. "1/16 = .0625"1.5mm = .059".0625 -.059 = .0035" (I actually meant .0025 when I wrote the original post, but that would also have been wrong!)So the 1/16" is .0035" too big. That's a little big, I think.Peteski, I think there is still something wrong in the numbers you posted.You wrote:"1/16" = 0.0625" or 1.65608mm, which is 0.15608mm larger than 1.5mm.0.15608mm = 0.0062" which to me is still too sloppy of a fit."1/16 = .0625 = 1.5875mm not 1.656081.5875 - 1.5 = .0875mm = .003444" (or about .0035")