So… Because i was drunk, and little bored over the weekend, i decided to make an adapter so i could mount my Dremel “rotary tool” and use it for giggles…
I think the design is really straight forward, and simple, and i’m sure some one else has already done this, or something similar, never the less, i’ll post this so others can get an idea of the workflow involved.
I started off by measuring the outside diameter of my Dremel. luckily for me, there are two features on the dremel body that are perfectly aligned on opposing sides to act as a ‘stop’ for the adapter so the dremel doesn’t slide down past that point.
Then i measured the inside diameter of the spindle clamps i have in place, and gave myself a tolerance of 0.1mm (i’ll explain later)
I also measured the clearance between the edge of the spindle clam inner diameter, and any nearby parts
(read back-plate/carriage of the spindle clamps :D)
Then i opened solidworks and set to building my part.
Knowing that the spindle clamp inner diameter is 67.125mm, and my clearance from the inner diameter edge, and the carriage was 27.52mm, i created a sketch, and drew a circle that was 75mm. on the “top” plane.
i then exited the sketch, and boss/extruded the circle to 3/4" thick
next i created a new sketch, and this time, instead of using the top plane, i used the flat surface of our new extruded part. I added 2 construction / center lines from one edge to the other in a + pattern. I then exited the sketch.
Making sure i had no parts or sketches selected, i created a new sketch yet again. This time, selecting the ‘top’ plane again. Using the construction lines as a guide, i drew another circle, centered by the construction line intersection, and made it 47.825mm for the dremel circumference. I exited the sketch.
I then selected my new circle sketch, and applied an extruded cut, making sure to go through all.
Now that we have the dremel hole, in our part, we need to add a cut in the ring as leverage against tight-fitting parts 
Next i create a square sketch, 1/4" wide, and centered on on one of the construction lines from earlier, but also spanning across the edge of our ring. then exited sketch.
I applied an extruded cut on our square sketch, again going through all.
Now we have a ring with a break in it 
Next i creates a new sketch, and this time i created 2 circles, centered on the construction lines from earlier. One circle was 90mm, the other was 67.025mm (67.125mm - our 0.1mm for fit and function)
I exited the sketch.
I applied an extruded cut the two-circle sketch, but this time i chose “blind” instead of through all, and set the depth of the cut to 0.5" (our stock is 0.75" so this leaves us a 0.25" ‘lip’)
Now we arrive at this part:
Now we’ll discuss the clearances and tolerances.
The reason i subtracted 0.1mm from the larger ring on the two ring sketch, was simply due to the fact that the dremel tolerances were “exactly” the dimension of the dremel. I know that stickers, grime, irregularities in the diameter due to being molded plastic, and whatever else on the dremel means that it’s going to be a tight squeeze the get the dremel into the ring, and will cause the ring to flex out in response. This means if i had made the dimensions of the larger ring exactly those of the inner diameter of the spindle clamps, it wouldn’t fit.
The lip was intentionally left on the ring, so that it will stay in place as i fumble around for the clamp screws and end-piece… It also gives me a surface to clamp on so i can clamp the ring down to the spindle clam body, while i’m tightening the spindle clamp, that way it doesn’t raise out, or get tilted at an angle.
Finally, using my rotozip, and some 3/4" MDF, i cut the ring out
https://www.youtube.com/watch?v=b9HZWDrTuVQ
And finally, i used a set of files, sand paper, and elbow grease to clean the part up, and here you can see it attached to the machine
Hope you guys enjoyed this, and can use it
Here are the solidworks files Enjoy!
Dremel_Mount.rar (2.8 MB)