ETS EC 150/3 issues

[palutena]

Hi Everyone,
my first post in this group, I hope I'm posting in the right place.

I wanted to ask the community about a couple of issues im having with the ets ec 150/3 sander, and I would greatly appreciate your insight.
I purchased this tool recently from festool recon. one of the issues im having is that the pad doesn't seem to spin freely when I am sanding edges of table tops. the sander acts more like a oscillating tool, and then every now and then it will start rotating and it will take off a lot more material, its hard for me to get consistent results (ive even ruined a project while sanding the edge) when for the most part it seems to just oscillate and then spin every 30 seconds or so for a few rotations. anyone have any ideas about this, is it normal? all of my older sanders seem to spin just fine on edges.

also, the sander is leaving weird rotational marks (not pigtails) on my tabletops (attached photo not mine, but is very similar to my experience). its seems like the outside of the sanding disc is leaving those curved marks. as a fyi this is happening with both hard and super soft backing pad, with 3m cubitron mesh disc and interference protection pad.

does anyone have any suggestions? maybe lubricating the machine? I have taken the backing pad off and cleaning all the debris in there and the rubber trim piece but that did not seem to make any improvements.
I should also mention that I can turn the sanding pad freely when the machine is off, but I can hear friction (it doesn't turn easily) and the pad doesn't continue to spin when my hand leaves the pad, its stops immediately where as my other sanders the pad will spin for a second or two. not sure if this is normal so I thought id mention.

thanks in advance for any help !
-Anthony

 

[Michael Kellough]

Are you sure you didn’t sand with a different machine prior to using the ets? The very clear swirl pattern in the middle doesn’t match the swirl in the upper half so they weren’t made at the same time. It looks more like pairs of boards sanded before joining.

Also ets machine are “random orbit” sanders. They don’t simply spin. The spindle also orbits and it will still orbit even if the pad isn’t spinning. If doesn’t do that the machine is defective. You can tell by watching the machine run while it is upside down under bright light. Highlights will make a tight circle.

 

[palutena]

Hi Michael thanks for the reply,
as I stated in the original post the photo is not mine, I found one online which looks similar to what im experiencing (round marks seeming to come from the edges of the sandpaper/sanding pad)

The sander spins and acts normally when it is sanding a table top or when there is no material at all. it stops the spinning action and only oscillates when im sanding an edge of a table, for example, that is one to two inches thick. when this occurs it take a long time to sand the material, and when it randomly decides to start spinning it takes off a lot more material very quickly, causing me to have inconsistent results.
hope that clears it up.
thanks

 

[Michael Kellough]

Sorry I didn’t read your text carefully enough.

The 150 sander is big for sanding edges. You can do it but it takes skill to keep the angle of the machine correct, AND keep the pressure just right to keep the pad spinning. I haven’t been able to figure it out. Sometimes it works…

Festool makes an edge sanding rig that works with some 125mm sanders. That device makes it easy to keep the angle of the sander consistent so you only have to concentrate on getting the pressure just right. It’s fairly easy to get good results.

Without that rig you need to make the work more like sanding a surface. Clamp a straight board (or stack of boards) even with the edge you want to sand and keep the sander mainly on the sacrificial wood. Also fairly easy, if the joint is straight and the edge square.

Random orbit sanders aren’t made to sand edges and if you can’t keep the pad spinning you’ll overheat a small area of the grip pad which will cause the abrasive disc to start flying off the pad. Festool pads are optimized to be flat so there isn’t much depth to the grip hooks and they’re easier to damage.

 

[Cheese]

Don't put any pressure on the sander, let just the weight of the sander provide the downforce. Also, turn down the suction of the vac to minimal or thereabouts. Again, high vacuum, dust extraction levels will also slow down/stop the disc from rotating and they may be contributing to the visible swirl issues.

If you're using different grits, vacuum everything before sanding with the next smaller grit, that includes the sander pad. Those swirls may be from the previous or the previous-previous sanding grit.

Festool specifically designed a sander pad brake into the ETS EC series. It's supposed to stop within a second or less so that you don't have to wait to put down the sander. I think it's one of the best features of the ETS EC series.

If none of that helps, you could try swapping out the Cubitron paper for Granat paper. The Cubitron particles are extremely sharp and they could be contributing to the disc stoppage issue because they "grab" the wood more solidly than the Granat paper.

Here's a comparison between Cubitron (Precision Shaped Grain ceramic) grit geometry and Granat (crushed ceramic) grit geometry.

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