Sanding Swirls with festool ETS 150

[mark mcfarlane]

Mike, This might be helpful, the first minute covers swirl marks with the ETS 150/3. https://www.youtube.com/watch?v=rZZyypf-Qqk Watch the whole video

Also, do yo have a vac connected to the ETS?

[Alan Lightstone]

Thanks for that link, Mark.

I always wondered if Festool made any sanders equivalent to the forced rotation orbital sanders like the Flex I use for car polishing.

I never realized that's what the Rotex is in "coarse" mode. Just learned something.

That being said, that Rotex really is a beast. I rarely use it.

[Chris Padilla]

Yeah, that pic looks like something possibly up with the sandpaper. I have never gotten or seen such marks on anything I've sanded with my 150/3. What grit sandpaper made those marks? How deep are they. Can you drag your fingernail across them and feel them? They look pretty deep.

On a side note, what kind of wood is that? Looks a bit like zebrawood but I don't think it is.

[Martin Wasner]

On a side note, what kind of wood is that? Looks a bit like zebrawood but I don't think it is.

Looks like oak with stain on it to me.



A random orbit sander is functionally incapable of not leaving swirl marks. All you can do is minimize them by going up in grit. Oscillation speed being cranked up helps, I think that's what Mel is talking about. Quality abrasives are a must as well. When a piece of the grit breaks off and gets trapped on the sheet creating a high spot, that chunk can cause more swirls than normal.

I don't have experience with what impact a vacuum has.

I don't think using as little pressure as possible is the answer either, but I've got nothing to base that on other than gut feeling.

[Mike Kelly]

Mike, on the right side of the pic I can see shadows of the outside of the sanding pad, but only the top of the circle. That could happen if the sander was weighted to one side rather than applying uniform vertical pressure. Did you start the sander in the air and drop it on the board, or start it while it was in contact with the board?

The smaller (orbital) circular scratches in the middle of the photo look very deep, as though there was some loose abrasive 'sharp crap' on either the board or paper when you started sanding. I don't think you would get that kind of 'very localized pattern' due to a sander or technique defect. As mentioned previously, did you try cleaning the board, pad and sandpaper before starting sanding? Have you tried rubbing your hand over the sandpaper to see if the surface feels irregular? Maybe you got a bad batch of paper, or some dirt in the paper storage. Are you using Festool paper?

If you bought the sander from a brick-and-mortar store, maybe you can take it back, along with your bad sample board and a fresh board and chat with the folks, try a different sander, or return the sander if you are in the 30 day window.

Thanks Mark. I turned the sander on while on the board. (Both the ETS EC 150/3 and RTS 400.) I took it off the board before removing power. I cleaned between each grit with a vacuum of the sander and board and wiping of the board. I used Festool Rubin2 sandpaper out of a brand new box. I went from 120, 150 and 180 grit. Each attempt to sand used new paper. I used slow movement with very little pressure and very low vacuum. After three attempts at staining of this project using Festool products, I went back to my old PC 333 and Makita pad sander with no dust collection which I have used for at least 20 years and the problems disappeared. I was also told I should go at least to 320 grit to get rid of swirls. The hickory would not take much stain at 220 which I also tried. So I am stuck with dust in the air still. I returned the sanders to ToolNut. They have been great through the whole ordeal.

[Bruce Page]

Attachment 341957
Here is what happened no matter what I did.
The orbit is 3mm. Vacuum was at minimum and pressure just enough to guide sander.

I have seen marks like that when sanding previously finished/painted wood. The finish will load up on the paper and cause the swirls. That piece of wood looks like it has a finish on it.

Mark, that is an excellent video. I wonder what that wall behind him would sell for!

[mark mcfarlane]

Thanks Mark. I turned the sander on while on the board. (Both the ETS EC 150/3 and RTS 400.) I took it off the board before removing power. I cleaned between each grit with a vacuum of the sander and board and wiping of the board. I used Festool Rubin2 sandpaper out of a brand new box. I went from 120, 150 and 180 grit. Each attempt to sand used new paper. I used slow movement with very little pressure and very low vacuum. After three attempts at staining of this project using Festool products, I went back to my old PC 333 and Makita pad sander with no dust collection which I have used for at least 20 years and the problems disappeared. I was also told I should go at least to 320 grit to get rid of swirls. The hickory would not take much stain at 220 which I also tried. So I am stuck with dust in the air still. I returned the sanders to ToolNut. They have been great through the whole ordeal.

Sorry Mike. Sounds like you are doing it all 'correctly'. I haven't had this problem (yet) with my ETS or other 2 Festool sanders. If the problem only occurred on a single sander I'd blame the sander. Maybe a bad factory run of the paper (seems unlikely), or a gremlin in your shop. At least you could take advantage of the return policy.

[Mike Kelly]

Bruce, the hickory started out as bare wood and a stain was added 4 times after it was taken back to bare wood to get rid of the swirl marks. The Festool sanders are so good with dust extraction that the sandpaper does not "load up". That is one reason I bought them. They are fine expensive machines, they just did not work for me here. With my older PC I had to continually vacuum the pad to keep it from loading up even with dust extraction attached to the dust port.

[Bruce Page]

The Festool sanders are so good with dust extraction that the sandpaper does not "load up". That is one reason I bought them. They are fine expensive machines, they just did not work for me here. With my older PC I had to continually vacuum the pad to keep it from loading up even with dust extraction attached to the dust port.

Mike, that has not been my experience. The sandpaper will quickly gum up when sanding off a painted or previously finished surface, even a stained surface. I see it all the time when sanding a lacquer seal coat or paint finish off of signs I made on my cnc. Typically, I will blow the gum flakes off the paper with high pressure air but sometimes I have to use a brass brush to remove them. I have never seen any load up when sanding bare wood.

[Mike Berti]

Most Random Orbit sanders will leave swirl marks to some degree. Mine (Rockwell and Makita units) do it sometimes as well. The motion of the sanding paper is of such nature. But we don't always see the marks and sometimes they are pronounced. One factor that was correctly mentioned is the pressure we apply. Another is when little chips of wood, old paint, or varnish get caught and burried in the sanding paper. These tiny spots will leave swirl marks. It depends on the wood surface and the sand paper. The solution is gradually working up in grits and using clean pads. It is worth preparing the stock before sanding.
A good solution is to use belt sanders when possible. They don't have this orbital move and the results will be cleaner.

[Mike Kelly]

Mike, that has not been my experience. The sandpaper will quickly gum up when sanding off a painted or previously finished surface, even a stained surface. I see it all the time when sanding a lacquer seal coat or paint finish off of signs I made on my cnc. Typically, I will blow the gum flakes off the paper with high pressure air but sometimes I have to use a brass brush to remove them. I have never seen any load up when sanding bare wood.

Bruce, this was just a stain, not any finish or paint. Didn't have a problem with the Festool but I did with the PC.

[Kevin Jenness]

When I first used my ETS 125, no problems with swirls. After a few months, I had consistent half-moons that required hand sanding to remove. After reading this thread I dug out the handle for my Fein floor sweep, hooked it up in line and opened the valve to reduce suction. Result, no swirls. So, thanks for the guidance.

[jack duren]

Agree...It's a orbital sander. There's no way to eliminate, only get to a point they are almost invisible. I would look into recommended papers for the sander of choice...

[jim sauterer]

I know this is an old thread but I was xperiencing the same swirls after watching the video mark referenced to in my case it was improper sanding by me thanks for posting the video mark

[mark mcfarlane]

I know this is an old thread but I was xperiencing the same swirls after watching the video mark referenced to in my case it was improper sanding by me thanks for posting the video mark

You are most welcome Jim.