Scooting Sander

[Seth Clayton]

Hi all!

I have a 5" Bosch Corded Random Orbit Sander. It has recently been giving me some problems while sanding broad panels. I've used this sander for many years, and feel like I have not changed my technique since before I was having trouble: I feel like I keep it very flat on the panel; I don't move it too fast; and I don't put a lot of pressure down onto the panel.

The problem I've been having lately is that it will be moving in one direction without any issues, and then it will start to resist the direction of travel and want to skip to the side. If I move in a new line about 10* from the previous line of travel, it will give up the resistance and move smoothly again.

The only thing I've ever changed with the sander is to put a firmer backer pad on. Is this causing my problems, or is my sander wearing out?

Thanks for any advice!
-Seth

[Keith Westfall]

I've used this sander for many years

Perhaps the oscillating mechanism is getting sticky...?

[Seth Clayton]

Perhaps the oscillating mechanism is getting sticky...?

Is it possible to service the mechanism? I’d say the sander is about 8 years old.

[Lee Schierer]

I have that problem with thin stock ( 1/2" or less) the cure is to clamp the panel down so it can't vibrate.

[Paul F Franklin]

You might try removing the sanding pad and cleaning the mechanism behind it. Tends to get a lot of sawdust packed in there tight and it can interfere with the oscillating motion. Compressed air or a small wire brush will do the trick.

[Tom Bender]

Have been having this problem recently also, with my Dewalt sander. There is a plastic shield under the pad that I replaced once. I have spares, will give it a try.

[Richard Coers]

Following. I'm hopping I can apply some of the answers to stop my dog from doing the same thing! LOL

[James Adinaro]

I have a Festool random orbit sander that has done the same thing since it was new.
I've always assumed it was changing or swirling grain on the workpiece that was causing it.
Interested to see if you find a fix.

[Seth Clayton]

Well I cleaned out behind the sanding pad and started clamping my thinner stock down. My issue has reduced quite a bit, and I think it has more to do with the clamping than the cleaning, as there was not much dust caked behind the pad. I notice my panels aren't vibrating as much, and I can see how that vibration could interfere with the action of the machine. As an added bonus, I don't have to use my second hand to hold the workpiece anymore! Wish I'd done it sooner, regardless of the original problem! Thanks for the suggestions everyone!

That does leave one question... What is the expected lifespan on our ROS's?

[Jim Becker]

If you are using dust collection, you can actually have "too much", depending on how fine the abrasive you are using is and that can cause, sticking/jerky movements, too. So as the abrasive gets finer, it may be necessary to dial down the extraction a little to keep things from getting "sticky".

[Seth Clayton]

If you are using dust collection, you can actually have "too much", depending on how fine the abrasive you are using is and that can cause, sticking/jerky movements, too. So as the abrasive gets finer, it may be necessary to dial down the extraction a little to keep things from getting "sticky".

Interesting! How can this be done? I definitely notice the problem is worse with the finer grits.

[Jim Becker]

If the extractor you're using with your sander doesn't have a speed control, you can get an in-hose attachment, probably from your choice of home center tool section, that has a little sliding door that can be opened to a variable degree to help vary the static pressure that the hose is maintaining with the tool. Higher end extractors, such as Festool, Fein and others typically have this feature right on the machine. Most shop vacs need the adapter to do it.

[Seth Clayton]

Another follow up. Thought I’d solved my issue with the clamped workpieces, but then I cleaned the filter on my shop vac. RIGHT back to an erratic sander. I busted out the 1/4” drill bit and put about 6 holes around end of the hose that connects to the vac. I’ll either rig something up to plug those holes when I need full suction or just get another hose for those times. Works great! Anyone else with an erratic sander and a shop vac hooked up to it, I’d recommend this method.

[Bill Dufour]

Either masking tape or a pipe sleeve that slides over the holes to cover them.
Bil lD

[Mark Daily]

Another follow up. Thought I’d solved my issue with the clamped workpieces, but then I cleaned the filter on my shop vac. RIGHT back to an erratic sander. I busted out the 1/4” drill bit and put about 6 holes around end of the hose that connects to the vac. I’ll either rig something up to plug those holes when I need full suction or just get another hose for those times. Works great! Anyone else with an erratic sander and a shop vac hooked up to it, I’d recommend this method.
I use a Shop Vac brand vac with my Dewalt sander and the vac has a drain hole near the bottom to drain liquid. I discovered by accident that leaving the plug off reduces the amount of vacuum dramatically. By partially screwing the plug in I can vary the amount of suction. Might work for you too.

[Jim Becker]

I can see how that might work, Mark. The advantages of putting the controllability near the tool are both convenience and also keeping the same general air flow through the hose. Despite the shop vac being more about "suction"/-static pressure, air flow still contributes to the cause. Any air coming out the drain could potentially be direct air into places you don't want it and raise dust levels in the air as a result.

[Tom Bender]

So that hole is into the dust bin? If so it will raise a huge dust storm in the bin and plug your filter faster.

Actually the best thing for your filter would be to reduce the amount of air it has to handle by choking down the hose somewhere. This will also reduce motor amps.

[Mark Daily]

I can see how that might work, Mark. The advantages of putting the controllability near the tool are both convenience and also keeping the same general air flow through the hose. Despite the shop vac being more about "suction"/-static pressure, air flow still contributes to the cause. Any air coming out the drain could potentially be direct air into places you don't want it and raise dust levels in the air as a result.
Definitely an advantage having control near the tool. No air comes out of the drain, it is actually being sucked IN the drain.

Not really recommending it over any better solution- just mentioning I discovered it after cleaning out the vac. When I hooked my RO sander up the suction was reduced so much I thought the vac had finally given up the ghost. Then I noticed I had forgotten to replace the drain cap. Saved me from buying a new vac!