# Random orbital sander variable speed



## dansnow (May 8, 2013)

I wasn't sure if this question should be in finishing or power tools. I recently got my first random orbital sander and the darn thing is driving me nuts!! I cannot keep it from jumping and hopping around when I try to use it It's almost like the sanding pad is rubber and grabbing the surface. If I turn the speed all they way up it's smoother, but unlike my pad sander it has a mind of it's own. I'm about ready to chalk it up as a bad investment. I only bought it because my 30 year old pad sander is wearing out and I had read that random orbitals gave a superior finish.

So, help, what am I doing wrong with this darn thing?


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## Loren (May 30, 2008)

Is it brand new? refurbished?

They are a little hard to hold onto when working
properly, but hardly so hard to control as you've
described. They do have parts that can wear 
unevenly and cause misbehavior though.

You're supposed to bring them up to speed before
putting them to wood. Not doing that may cause
problems.


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## dansnow (May 8, 2013)

It's brand new, a TackLife. I tried the letting it get up to speed and that did help. It has a hard plastic dust collector, and I have found that if I put one hand on it and the other on the palm grip on top it is a lot easier to control, but having to use both hands is a bit of a pain as I don't always have the opportunity to use clamps.

Thanks for the tip, it helps.


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## crowie (Jan 21, 2013)

G'Day Dan,
Not a brand we have downunder.
I use a Bosch Blue unit which I find very good.
I found this video on youtube and this blokes gives yours a good rap!


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## RichT (Oct 14, 2016)

My old Porter Cable sander did that. It was from the early '80s, and was a bear to handle. I still have a couple of projects from those days with "donuts" in the finish. No one would notice them unless I pointed them out, but they're there.

Contrary to what might be intuitive, starting the sander on the surface of the wood helps prevent that swirly dance some of them do. Set it flat on the board, cup it in both hands down near the base and switch it on. You should be able to practice that and get good results. There's something about certain sanders that makes them want to swirl around when they touch down. I have no idea why. Some gyroscopic effect maybe.

That said, in the 5-inch ROS family, I have Makita, DeWalt, Bosch and Porter Cable (not the original one mentioned above) and none of them exhibit that problem. The PC is probably the worst sander of the bunch, and the Bosch the best, but they are all useable.


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## dansnow (May 8, 2013)

Thanks for the info and the link to the review. The fellow in the video sure made it look easy, I didn't see either one jump once. It looks like I just need to use the thing and get used to it.


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## EarlS (Dec 21, 2011)

I have a Mirka Deros which has a variable speed function. At low speeds it wants to jump a bit on wood that isn't especially flat or when I try to move too fast with a coarse disk. It will also jump if I push down on the sander rather than let it sit on the wood. I typically hold it at the lowest part of the motor housing, just above the ROS section. Generally, I only use the lower speeds with the really fine discs (320+). Let the ROS do the work, don't force it.


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## ralbuck (Mar 12, 2012)

I have a Bosch with no issues; unless I press hard with a very rough paper on it. Otherwise it glides nicely with one hand. I also have a DeWalt-not quite as smooth; but, still very manageable with one hand. 
I am also a small not overly strong guy.


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## cabmaker (Sep 16, 2010)

sounds like you need to replace the pad with a soft one


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