Introduction: Simple DIY Flap Sander
We’ve got a quick tip today - how to make a simple DIY flap sander. There are a lot of elaborate DIY flap sanders out there, but this is one you can make in a pinch. It’s great for getting into hard to reach spaces that are hard to get with a typical flap sander. Plus it’s super flexible: you can make it long and skinny, you can make the sandpaper itself longer or shorter, and you can swap out the grit whenever you need to.
Tools and materials needed:
Step 1: Clamp and Cut
First clamp down some ⅜” aluminum bar stock and cut off the length you need with a jigsaw using a metal blade. We cut off a length that was about 4”, but you could go longer if you needed to.
Step 2: Turn Into Split Mandrel
We’ll turn this piece of aluminum into a split mandrel to hold our sand paper. We placed it on our drill press V block to keep it centered (which we clamped into place), and cut a slit into it on our band saw.
Step 3: Insert Into Drill
Then pop the split mandrel into your drill and place a folded piece of sandpaper in the slit. Tighten the split end around the sandpaper with some pliers.
Step 4: Enjoy!
This is great for getting hard to reach spaces that a store-bought flap sander can’t get to, and it’s really so easy to make. Hope y’all found this helpful, let us know if you have any questions!
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16 Comments
5 years ago
One end of the sandpaper strip has only its smooth side showing, so may I suggest a small improvement ?
Cut the sandpaper strip in half, and glue the ends back to back to fit in the mandrel slot, then both sides will show grit to the workpiece. (Needs just a slightly wider slot.)
Reply 5 years ago
They folded the sandpaper in half lengthwise so it has the business side of the sandpaper making contact all of the time. You can see it clearly at the 1:10 mark.
Reply 5 years ago
Correction: it's actually the 36 second mark. I looked at the total time instead of the elapsed time.
Reply 5 years ago
Thanks for the assist autotech1 :D and for the suggestion electrofrank!
Reply 5 years ago
Ah yes. I should put my glasses on. And that makes it reversible as well.
5 years ago
; D
5 years ago
You can do the same with 1/8" rod for a dremel. That gets into really small places.
Reply 5 years ago
Yeah, great suggestion! I'll add that and die grinder to the suggested ways to do this :)
5 years ago
NIFTY! The timing is just right for me. DI was agonizing on how to accomplish a tight corner and I've never heard of a "flap" sander before! Oooo who! Thanks!
Reply 5 years ago
Yay, so glad we could help out :D Good luck with your project!!
5 years ago
Thank you.
Your youtube link is incorrect. It's set to the instagram one.
Reply 5 years ago
AH, thanks so much for catching that!! All fixed now :)
5 years ago
Useful one, thanks
Reply 5 years ago
NP! Glad you found it useful :)
5 years ago
I find it either more satisfying or more efficient (perhaps less fussy than making numerous folds?) to glue partial sheets of sandpaper back to back. I let them dry completely, and with an old pair of shears long ago dedicated to sandpaper, cut several strips of the double-sided abrasive paper at one time. Mostly I've used spray adhesive, a light coat applied from a clean spray nozzle in the lower end of the adhesive's recommended temperature range for application, to keep the glue in a thin, even layer, as I want my abrasive faces to stay as parallel as possible for use in a couple of other custom sanding tools for metal fabrication.
Reply 5 years ago
Neat, I'll try this out with some pieces we have to see how it works, thanks for the suggestion :)