In the last blog post, we discussed the differences between self adhesive (PSA) and hook & loop (H&L) sanders and sanding discs. Much of that post was taken from an interview with Ralph Bagnall from Woodcademy that we previously published in our e-newsletter. Since that post, Ralph has reached out to us with a clever way to adapt a hook & loop sander to accept PSA discs.
Here’s what Ralph writes:
It is true that hook & loop discs cover most of my sanding needs in the shop, but H&L has one inherent issue; the hook and loop layers create a somewhat soft interface under the sanding pad. This is not really an issue most of the time, but it can allow the sanding disc to roll over the edge of a panel or mortise, rounding it slightly. Normally, this is fine; we want crisp, but not sharp, edges. But with hinge mortises, drop leaf edges and other details, rounding those top edges can lead to unsightly gaps. This is where a PSA disc, stuck to a stiff backer, is the right sanding method.
Rather than having a PSA sander that gets used infrequently, or having to remove and replace the pad on my H&L sander, I simply made an adapter plate that attaches to my sander’s H&L pad to hold PSA discs. It is inexpensive, easy to make, and converts my sander in seconds with no tools needed.
The adapter is made from 0.080” polycarbonate. This can be found in 8 by 10 inch sheets for under $10.00 at your home center. It also needs some self adhesive loop to lock onto the sander pad which can be found online or at a fabric/craft store. The polycarbonate is cut into a disc to match the size of your sander.
It can be left without holes for dust collection but I used a sanding disc to mark the 5 holes that my sander uses, and drilled these out with a 3/8” forstner bit. The self adhesive loop was applied to the polycarbonate disc, then the holes cut out and the loop trimmed using a utility knife. That’s all it takes.
Now when I need the stiff backing of a PSA sander, I just peel off the H&L loop, engage the adapter to the hooks on my sander’s pad, and have a flat surface for the PSA discs to adhere to. The polycarbonate is impact resistant so it will not shatter in use, and the face releases the PSA discs without too much drama. Make up a couple of these adapters and you can actually reuse your PSA discs by simply swapping adapters.