7

I have a sanding job that requires sanding inside many small pockets - a few thousand. I tested the speed I could get doing it by hand, and it might be as much of a week of non-stop work. It's time for power tools.

What tools are there for sanding inside small pockets, quickly? The pockets are slightly larger than 1" x 1", and 1" deep, plus a 45º slope extending out one side, for the smallest pockets. There are larger pockets in the job, also. Heck, what tools are there overall, for sanding inside pockets?

I know some people use emery boards, others use sanding sticks, some use abrasive nylon rotary tool wheels. What all options are out there?

A sample of the pockets I need to sand. Each one is a little larger than a cubic inch, and slanted on one side.

  • What are the pocket dimensions? – Matt Apr 15 '16 at 18:36
  • Slightly larger than 1" x 1", and 1" deep, plus a 45º slope extending out one side, for the smallest pockets. There are larger pockets in the job, also. – baudot Apr 15 '16 at 18:47
  • Few questions that are just for curiosity. What are you using these for? Could you line the boxes with flock? How did you make the recesses? – Matt Apr 15 '16 at 19:15
  • 1
    Have you surveyed your customers to see if there's an expectation that the pockets will be free of mill marks? I'd certainly sand all the top edges, but I'm not convinced that the interiors need that much work. – Aloysius Defenestrate Apr 17 '16 at 15:47
  • 1
    If those pockets hadn't been machine made, "How do I make 1000's of pockets?" would have been the first question! – FreeMan Apr 18 '16 at 15:54
8

Personally I would have aimed for an internal milled finish that didn't require sanding, that's the ideal. Obviously too late for that now and I don't know if that's possible with the Shopbot and the bit you were using anyway.

Instead of sanding to smooth the rough surfaces I recommend scraping. It will be faster, give a better finish and is more controllable, with much less chance of accidentally rounding edges.

For the flats the ideal tool is a bar scraper or scraping chisel. These are one of the tools traditionally used in planemaking for flattening the beds on wooden planes. These beds were never sanded as far as I'm aware and the finish is as smooth as you could ask for.

You can make one yourself from a beater chisel, just grind the end flat:

Bar scraper/scraping chisel

Here's the same thing explained in Classic Hand Tools by Garrett Hack:

Scraping chisels explained

As you can see from the old cast-steel chisel to the right in the photo above you don't have to start with a chisel that has flat sides (a firmer or registered mortise chisel), a bevel-edge chisel will work fine.

Ideally a tool like this would be specially heat-treated to make it a dedicated scraper (the tip being made ultra-hard) but a chisel of standard hardness is more than adequate for limited use.

| improve this answer | |
  • 2
    I wanted to say scraping but figured the parts were too big. Didn't even know they made scraper chisels. So when are we changing the site to graphus.se? – Matt Apr 16 '16 at 17:12
  • @Matt, LOL I didn't know about scraper chisels either until I found out about them in the context of planemaking, hard to discover them otherwise as they're a pretty specialised tool traditionally. I think they should be known and used more widely though, for example a few jobs a chisel plane is the usual pick for a scraper chisel will do as well, a little more slowly perhaps but better (almost no chance of digging into the surface). – Graphus Apr 18 '16 at 15:21
  • 1
    If this is still early prototyping stage, it may not be too late to change the milling settings and/or bit to get a better quality finish that doesn't need to be sanded. Heck, even if OP is heavily into production, it may be worth investigating that to eliminate the finishing step. – FreeMan Apr 18 '16 at 16:02
8

Bandfile Belt Sander

Not advocating any particular product but showing the product picture

enter image description here

Image from Harbour Frieght

That should help you get into the tight spots quickly and efficiently. Only issue would be the corners. For that I would use a small rotary tool. Hopefully you have one that will fit in there. Mine is a little too clunky to get into a hole that small. They make all sort of attachments for those things so a sanding ball might work just as well to conform to the shapes you have.

| improve this answer | |
4

You could use a small-diameter sanding drum on the drill press, similar to that pictured below.

drum sander
(source)

You would have to lower/raise the drill press table each time you move to a different pocket, but that's not too big of a hassle.

It's hard to tell by your pictures, but the sides of the pockets look straight, so this should work for the sides.

The bottoms, however, you'll need a different solution.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.