Sanding...done before?

New maker here with lots of excitement.
I had a thought about sanding and wondered if anyone has tried this. For inner cuts that are small and tough to sand, has anyone tried using an end mill that can do sanding? I assume a tool path could be created to sand those tough little spots. Just a thought, maybe this is something everyone does already?
What do you cnc’ers think - cnc sanding?

Here’s a whole thread of my experiments around CNC sanding:

I used large-ish sanding pads but there is no reason why it could not be done with smaller sanding heads, and appropriate toolpaths

The key element is having some way to keep the sanding pad against the surface, so soft cushion above the pad itself, or a spring-loaded mechanism (I mean for bottom surfaces)


Thanks for the reply. I figured someone would be on to this idea already. I didnt bother with google yet. Seems like the brains are all on here : )
Great work!

Based on a post in one of these threads I bought a set of these:

I planned to use them in a dremel like tool to clean up vcarves. I have not used them yet, arrived after my last vcarve and I got distracted.

I think these would be better suited to hand held use for detail work but I like the linked thread for smoothing out large areas.

Although, maybe the puffy nature of these and the recessed screw would allow them to work on larger areas from the CNC. I’ll give it a shot when I get a chance.

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Heres a thought that just popped into mind. What if it is soft wood and the original ‘cutting’ is actually just done by a sanding ‘end mill’. More passes but it would be smooth at the end. Maybe, im trying to invent the wheel a bit, but that is sort of how this creates excitement for me. I saw a bicycle with square wheels and it functions haha. Cheers to making a new reality.
Thanks for the replies

If you want a really smooth wood surface the keys to this are:

  • cut cleanly into fine-grained wood
  • use a succession of sanding grits starting w/ the finest grit which will remove the largest defect present in the wood’s surface
  • buy a pack of Micro Mesh abrasives suited to the work which you are doing
  • don’t skip grits — doing this you can achieve a glass-smooth surface if you are cutting a tropical hardwood such as lignum vitae or Ipê and/or also spray w/ a suitable finish (I like to use lacquer, but I’m old-fashioned)

If leaving the wood essentially unfinished (say using a natural oil finish) you can follow on w/ “boning” which is a technique from bow-making where the surface is rubbed with a hard material such as a bone or rounded piece of glass — it compresses the wood fibers at the surface.


I imagine you could leave a small amount of finish stock & use one of these perhaps with some air to help clear the sawdust?
You would need a CAM system that supports those tool shapes, and the ability to just pick out the small corners, hard to reach areas.

Right !!
Its all out there and available. Thanks for the link, what a great additional idea!
Stirring up ideas!
Thanks for the replies

Is this a thing…
Sanding glass instead of ‘scrathing’ ?
I assume it would create a smoky opaque look? Or am i getting ahead of my own thoughts.
Theres gotta be someone whos tried…?
Is it a fail or an idea?

The Micro Mesh adhesives are hard enough to cut glass, and available in fine enough grits that they can be used to achieve an optically smooth surface (they were originally used in manufacturing lenses).

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Thank you!
Ill be adding this to my ideas and projects in the future!
Very kind

Just throwing it out there as another way to use your CNC for sanding. I was doing some 26-inch diameter surfaces for a dexterity boardgame and found sanding to be real time consumer. I built an adapter so I could fit my DeWalt RO sander in the spindle mount and programmed a spiral operation so the CNC could do the sanding. "This allowed me to work on some other part of the project while letting the CNC do the sanding work. I favored the Mirka products–the Abranet 400-600 pads and the Abralon 1000-4000 pads.


Hmmmm. I bought some burnishers awhile back, wonder how that might work on wood assuming there was minimum tear-out.

Instead of google, could you explain please.

What a great idea. I bet the projects look amazing.
Efficient and smart!

I would worry about metal transferring to the wood and discoloring things — one of my bows still has a stain from a 14 karat ring I used to wear — I had to purchase a second set of Micro Mesh abrasives when I started using them on metal.

There may be other issues with this whimsy but I doubt sloughing metal would be one of them. Burnishers are made from very hard steel, meant to burnish other metals including steel, and are very smooth so as no to leave marks. OTOH, few metals are softer than gold.

Burnishing is the process, typically, of using hardened smooth steel to either flatten a metal surface or to draw out an edge on another piece of steel. Say you had scribed a line in a piece of metal and regretted it. Depending on the metal, and the line, you could run a burnisher over the line, flattening the furrow and minimizing or hiding the errant line. Cabinet scrapers are finished square on the edges then a burnishing tool is run over the edge to turn up a lip which acts as a cutter. Burnishing is also use to give metals certain texture like effects, mainly by altering reflection angles in patterned areas.

All that said, I went back and looked at the milling burnishers I have (and hardly used) and think they may not be useful here but I may one day experiment.

Thats a great explanation thank you.
Hopefully i rattled your cage a bit to get you going on your ‘one day’ project.
Id love to see the pictures of what you come up with.
Maybe even pictures of the mistakes and your ability to mend those issues.

Enjoy your time

I have used these sanding sticks with good results. The stick is spring loaded and you can rotate the belt when you wear out a point.

These are available from Amazon and most woodworking stores.