3 inch thickness sander

[threesixesinarow]

I use this sander to make little wood pieces more uniform. It’s similar to lighter open-sided machines from Performax and Jet, but smaller and not really practical for finishing anything long, thick or wide.

Like on those, the sanding head moves to adjust thickness. Both it and the feeder take 3 x 24” belts. Pressure bars like on wood planers are on both sides of the bottom roller, with the front one segmented to allow narrow pieces to go through.

It’s very small! But so are the parts I use it for - the smallest pieces I’ve run through are about 1/2” long and 7/32” thick, even 6” long pieces are rare.

Apart from the self aligning ball bearings most of the parts and materials were recycled: a wiper motor, wringer washing machine and dot matrix printer rollers, old structural channel, and steel plate cut from a treadmill.





Delrin pressure bars, and tracking adjusters:



Sanding head slide plate showing bolted together construction:

[DIYer]

Thanks threesixesinarow! We've added your Thickness Sander to our Sanding category,
as well as to your builder page: threesixesinarow's Homemade Tools. Your receipt:

Thickness Sander by threesixesinarow

tags: thickness sander

[Frank S]

If you have a way of configuring it so 2 of the end rollers of dissimilar sizes are together you can have a centerless grinder for dowels and cylindrical items

[Drew1966]

To be brutally honest, it looks rather over-engineered, but if you’re happy with it, that’s all that counts.

[threesixesinarow]

To be brutally honest, it looks rather over-engineered, but if you’re happy with it, that’s all that counts.

That’s something I struggle with, but keep in mind how small it is!

The first designs I looked at for reference were bigger home built ones like guitar builders use - there are many great plans for working with relatively long pieces, ranging from belt machines like Horwitz and Rancourt’s in Fine Woodworking 23, or drum machines like Beserkleyboy’s, to hand fed ones using a lathe or something simpler to support the sander, like this or this, or like Michael Paley’s recent submission here.

Here’s an example toward the smaller end of the size of things I run through it, though. I wanted something that was more consistent but not slower than just rubbing each piece on sandpaper by hand.

[threesixesinarow]

If you have a way of configuring it so 2 of the end rollers of dissimilar sizes are together you can have a centerless grinder for dowels and cylindrical items

That’s something to think about!

I think the relative speeds of the belts on this are about right for that, but maybe not the size of the wheels - I wonder if a radiused, slightly skewed platen would work instead of the bigger, cutting wheel. But then the easiest way to do that here would mean swapping the speeds of the two sanding belts.

[Frank S]

You really only need 1 belt in a centerless but you do need dissimilar size rollers or speeds there are quite a few videos showing the operations of a centerless belt grinder. It is actually better to have a plain or rubber wheel rotating in the same direction. Depending on which direction your belt is running depends on whether you position the cylinder above or below the center line. there is also a chart showing the distance offset from center relative to the diameter of the cylinder being ground or polished
Thrufeed Centerless OD Grinding Parameters and Troubleshooting.pdf

[threesixesinarow]

Thanks! I sometimes need small, funny diameter wooden dowels and making them this way would be more efficient than abusing a turret lathe box tool like I do now. The cedar ones in the bottom of the picture above are a little smaller than 3/16.



After I first looked into it and seeing how massive even the smallest centerless grinders were (like the Schaublin I grabbed this ebay picture of) I learned you can buy attachments for bigger belt sanders - I don’t think this is the one I saw but it looks similar and has a demonstration video:

Products - Scantool

[Frank S]

I am getting set up to make a compact diameter double action telescopic hydraulic cylinder After researching and contacting far too numerous tubing suppliers to mention on 3 continents I came to the conclusion that the only way to make my prototype is to buy tubing already with the correct honed diameter and deal with the OD's myself due to the cost of having to special order some custom made This means over the next couple of months I will be having to make my own centerless grinder which I plan on being a belt sander with attachments

[threesixesinarow]

I look forward to seeing the grinder if you can share it!