I recently purchased this 240v hand held belt sander, and wished I had done this years ago. They are available from various retailers. The manufacturers details are here: https://www.proxxon.com/en/micromot/28536.php
It has three positions, quickly selectable, to help with awkward access. I have found it useful for cleaning off carbon and heat staining on tubes, Initial sanding of stainless steel components and most usefully, smoothing down fillets after brazing. I found you can access most fillets between tubes and quickly smooth them down. The only area it seems to be too wide to fit is the seat tube / down tube junction which can be tight.
The belt can be applied firmly on the lower flat surface, or more gently using the top surface of the belt. Smooting of fillets is ,of course, done with the tip. Speed can be varied with the potentiometer. I have no guidance on which speed to use, and there are no speed marks on the device, so it is trial and error. There is a simple side to side adjustment using a screwdriver so the belt can be centred on the machine should it become offset. Belt changing is straightforward by pushing firmly on the tip of the belt carrier to compress the spring loading, then sliding belts on and off.
The machine comes supplied with a small number of carborundum belts. These are available in 80,120 and 180 grits. I feel these are most suitable for woodworking. The best option for metalworking are the silicone carbide belts, which are only available in 180 grit, but give the best finish. It is a shame these are not also available in coarser grits, and indeed finer ones.
My main criticism of the machine is the belts do not last very long and are a little flimsy. The are held together with a piece of tape, which eventually can snap, often prematurely. Also the silicone carbide belts can be difficult to find. It can also get quite hot with extended use.
SNH 9/01/2025
2 thoughts on “Proxxon Belt Sander”
See if you can find some scotch brite belts for it. There are places that will make you custom belts in the length needed if not readably available. It seems to be cheaper to buy wider ones and then split them. I have found them much more forgiving for smoothing out fillets than the usual belts.
The snapping that you mention usually means the belts are too old. It seems they have a shelf life.
Thank you Krus for the tip. I was unaware scotchbrite belts existed. I will see if I can find anything suitable to try