Simple Belt Sander Blocks

Handheld sanding blocks are a must for every woodworker. They allow you to easily hold sandpaper, remove unwanted material, and smooth projects. There are many commercially available sanding blocks, but these sanding blocks can be made quickly from scrap 2x4s and spare dowels. The block is split for about three-quarters of its length, and the belt is tensioned with a removable dowel.

Step 1: Design

With this design you can virtually create sanding blocks in any shape or angle you can think of. I have uploaded the dimensions of these two sanding blocks in both PDF downloads as well as the SolidWorks files used to create them.

Step 2: Parts

The only materials you need for this project are:

• Scrap 2x4s
• 3/8 dowel
• Belt Sandpaper Size 3x21

Step 3: Cut 2x4

Using either a band saw or table saw, rip lengthwise down the 2x4 till it's 3 inches wide and 9 5/16 inches long.

Step 4: Router Edges

Using a 3/8 inch roundover bit, round the four ends of the block.

Step 5: Drill Dowel Pin and Relief Hole

Drill a 3/8 inch hole 1 inch from one end and a 1/2 inch hole 7 inches from the same end. These holes will serve as a location to insert the dowel to create pressure across the sandpaper belt, and to disperse stress to keep the block from cracking.

Step 6: Router Finger Grips

Set up the fence to rout a 1/4 inch deep cut with a 1/2 inch radius starting and ending 1 inch from each end.

Step 7: Make Relief Cut

Cut an 1/8 inch wide slot through the dowel pin hole to the relief hole. This will bisect the sanding block and cause it to separate with the insertion of the dowel pin.

Step 8: Cut Dowel Pin

Cut 3/8 inch dowel to 3 inches in length. Sand a bevel on one end. Slide the sandpaper belt around the block. It should be mostly tight while sliding over the block. If it does not fit, cut a little more off the end of the block, re route the ends of the block and repeat as necessary until the sandpaper fits. If the sandpaper is loose, cut a new dowel pin with a larger diameter until sandpaper is tight.

Step 9: Size 2x4

Cut the width of the 2x4 down to 3 inches wide and 9 91/6 inches long. Cut a 45 degree angle on one end.

Step 10: Drill Dowel Pin and Relief Hole

Drill a 3/8 inch hole 1 inch from one end and a 1/2 inch hole 7 inches from the same end. These holes will serve as a location to insert the dowel to create pressure across the sandpaper belt, and to disperse stress to keep the block from cracking.

Step 11: Router and Round Corners

Using a 3/8 roundover bit, router the top edge of the square end. Using a sander, roundover the 135 degree angle on the top of the sanding block.

Step 12: Make Relief Cut

Cut a 1/8 inch slot from the square end of the block through the dowel pin hole to the relief hole. This will bisect the sanding block and cause it to separate with the insertion of the dowel pin.

Step 13: Router Finger Grips

Set up the fence to rout a 1/4 inch deep cut with a 1/2 inch radius starting at 1 inch from one end to 7 inches in.

Step 14: Cut Dowel Pin

Cut 1/4 inch dowel to 3 inches in length. Sand a bevel on one end. Slide the sandpaper belt around the block. It should be mostly tight while sliding over the block. If it does not fit, cut a little more off the square end of the block, re route the ends of the block and repeat as necessary until the sandpaper fits. If the sandpaper is loose, cut a new dowel pin with a larger diameter until sandpaper is tight.

Step 15: Results

This was a quick and easy project that I originally found in the October 1999 copy of American Woodworker. You can view the publication here.

Comments

[wannabemadsci]

I just love this concept!

A thought: Would it be possible to taper the slot with the slot wider at the center of the block and thinner near the outer edge so that the dowel could be inserted by hand in the middle and slid toward the edge (thinner end of the slot) to expand the wood block and tighten the belt?

[tomatoskins]

That sounds like a very interesting idea! Then there would be no need to use a larger dowel when the belt starts to stretch. If you make one please share the results!

[Owl Trained ED Doc]

Another option would be to place notches at intervals, rather than sliding.

[JAC_1961]

Great plans! Definitely going to make myself a pair of these. Think that I'll use maple, just because I have some. Another plus is that sanding belts last better due to the cloth backing and they're made to stand up to the heat of power sanding.

[JmsDwh]

And you can just rotate them to get fresh sand paper. Great design!

[nashville_bill]

Troy,

I made one of these, but my belts won't bend around that small of a radius without damaging the belts. Can you tell me which belts you are using?

Thanks,

Bill

[tomatoskins]

The belts I'm using are linked in step 2.

[nashville_bill]

Thank you; I missed that.

[Lovetra]

My wife, Lovetra is playing with all of my tools now that I can't, (I'M ENVIOUS, BUT DELIGHTED), is excited about your sanding blocks for two reasons. 1. She says she messes up the foam sanding pads too quickly, plus they are awkward to hold and use on some things, and 2. Having re-cycled a couple of damaged belts, she discovered they are a better quality material than ordinary sandpaper.

She made stationary sanding blocks by cutting the belts in 6" by 3" pieces, gluing them to some 1/2 inch scrap plywood, she had cut 3'' by 10 ". She then drilled a hole in each end to fit the workbench dog hole spacing. She says it stabilizes the sanding blocks on the workbench so that she has both hands free to manipulate small pieces to quickly smooth or de-bur a lot of her projects with the sander belt material holding up "for-ever" in competition with the foam pads.

It's her belief the longevity of your sanding blocks plus the mobility of taking them to the project she can't move to her workbench makes them worthwhile. I think she is in my, her inherited, garage workshop making a couple as I type this up.

[tomatoskins]

Haha I glad that she has found these to be as useful as I have! They really are much higher quality than standard sandpaper. I made these blocks two and a half years ago and I've never needed to replace the sandpaper. These are used on almost every project I make.

[Azze01]

If someone has a couple of belts kicking around this is a neat project to make use of usable material. If you have to buy belts for this purpose, I think this is the most expensive version of a sanding block possible. In this case I would rather try to find a way to use sheet material, for it comes at a couple of cents a stack.

Nice project though.

[ColR]

Found a link to this design duo in my junk mail - very impressed and I will definitely make a pair. Than

[charlessenf-gm]

Thank you for this. And the plan! Question: how did you determine the size(s) of the blocks? I have my idea, curious to learn if you used a similar approach.

BTW, with Charismas down the road, these make very interesting gifts for the family wood worker - give her/him an EyeObie Belt Sander!

[tomatoskins]

Since I made this over two years ago, I'm entirely sure, however I think that I let SolidWorks do all the math for me. I designed the shape I wanted then changed the length of the block until the perimeter matched the circumference of the belt I was using.

[charlessenf-gm]

Ah! an 'app.' I was thinking of doing the same thing 'manually' with a ruler! Never thought of using an 'app' but that's the way to go if you've got such a thing!.

[DennisO22]

Excellent. The simplest ideas are always the best.

[mattcastro]

love this! definitely making some of these

[Roboman123]

Sounds cool

[kdirja]

It is a good idea for my sanding block improvement, usually I glued the belt sander, and quite difficult to peel off.

[bruce.desertrat]

This is brilliant! Such a simple design, but so functional.