Handle / Backer for Stewmac Nut Slotting Files

The Stewmac Gauged Nut Slotting Files are great and you should be using them! But they are a bit fiddly to hold and existing handles are expensive.

 

Boost MeBoost me if this helped you!

 

So, I decided to make handles for these files that are gauged to perfectly fit each file. Instead of using set screws to clamp down on the file itself, these handles are individually gauged for press-fit on the file. These handles work well and cost less than $1 to print.

 

The handles are made from 3 pieces:

1. Main Handle Half 1 - I printed on a textured bed with Basic PLA. The holes are sized to fit three M3x8 BHCS Machine Screws. This part works for all file sizes.
2. Main Handle Half 2 - I printed on a textured bed with Basic PLA. The holes are sized to fit three M3x5x4 Round Threaded Brass Heat-insert Nuts. This part works for all file sizes.
3. Shim - I printed on a smooth bed with Matte PLA. I recommend using a contrasting color to the handles above as it makes it easier to see the thickness when selecting a file. This part includes a label (admittedly it looks a bit rough, but it won't show on the completed part) so you can easily pick the right one when assembling. This isn't 100% necessary if you don't have an AMS. The shims are sized per file and are slightly undersized so the tightened screws have a good grab. 

I opted to not include labels on the handles because the file itself is already labeled. 

 

Sizes: I have included shims for the following sizes. If you need another size, drop a comment. 

• 0.010" - Note be VERY careful removing this from the bed. 
• 0.012"
• 0.013"
• 0.016"
• 0.024"
• 0.028"
• 0.032"
• 0.035"
• 0.042"
• 0.050"
• 0.053"
• 0.056"

Assembly: 

1. Print all parts. Plate 1 has a bunch of handles on it. Plate 2 has all shims. Plate 3 has 1 pair of parts to make a handle.
2. Use a soldering iron to press in the heat-insert nuts. Make sure they go in straight and to flush. Don't push further than flush or you could bend out the back portion. 
3. Let the heat-insert nut fully cool before moving further. If not, the softened plastic may allow the nut to turn and spin freely. 
4. Use the machine screws to assmble both handle parts with a shim in between. Before tightening down all the way, insert the file all the way against the shim. Tighten down the machine screws, but don't overdo it. 
5. If the file is loose at all (due to printer tolerance differences), you could shift the file so that the handle grabs a little bit of the plasti-dipped portion of the handle. 

Note: Nut Files are Stewmac Part Number 0928 (full set).

 

Gridfinity holder that works with these handles: https://makerworld.com/en/models/1245775-gridfinity-for-stewmac-nut-slotting-files-holder#profileId-1267182