I had a need to adapt and use my Harbor Freight angle grinder as a benchtop disk sander, so I bought a 5" (127 mm) backing pad for about $10 and put together a simple build, complete with slotted table and miter gauge to produce an inexpensive benchtop tool.
Step 1: Prep the Pad
Using the same technique of making my own sanding disks as shown in my Instructable "Renewing Sanding Disks", I modified one slightly by punching a 3/4" (19.05 mm) diameter arbor hole and cutting relief slits so the retainer nut would nest subsurface.
Step 2: The Build
I made a short video that demonstrates various capabilities of the tool. Since particulars as to dimensions will vary depending on the brand employed, I have omitted them for the most part and simply show working concept and key features:
- Barrel style full body clamp with easy on/ off mounting
- No physical or mechanical modification to the tool is needed
- Slotted work surface table, adjustable in/ out, is centered with disk
- Bench hook (lip) on front edge of base promotes immovability using just a single clamp
- Simple "T" style adjustable miter gauge aids in precision work
- Disks can be changed while tool is mounted by simply loosening and sliding off slotted work table
- Easily accessible on/ off switch
- Simple construction allows fabrication from cutoffs and drops
- Model-makers especially, will find this tool most useful
Step 3: Parting Thoughts
For enhanced safety, a guard would be advisable, however I have yet to install one.
Hearing protection is a must for all but the quickest uses.
I use mine outside, so dust collection is not necessary, but a small shop vacuum would be beneficial if used indoors.
I should have used a fresh disk for the video, it would have cut cleaner with no burn marks.
This is a perfect example of when it is more efficient to put work to the tool instead of tool to the work. Much smaller, finer items can be processed with this setup than can ordinarily be had with the tool used in it's native form, also operator comfort is greatly increased since it is held securely in place.