random orbit sander

Could be the sander, could be how much pressure you are applying while sanding (let the sander do the work, you shouldn’t be pushing down on it), could be the range of grits you are using; ie, make sure you don’t start out on a too coarse grit and make sure you move up to the finer grits but don’t skip in btwn grits to get there. Also, make sure you are using a good quality manufacturer for your sand paper.
Good luck, I hope this info helps.

-- "You get what you inspect, not what you expect"

Like Pat said, you might be using too coarse of a grit and too much pressure. Try a lighter touch and don’t start with 60 or 80 grit unless you’re really trying to remove material. Start with 120 or more. To smooth stuff like glass 180 or 220 will work great. I agree, get the better quality paper like the 3X at HD or similar.

It mighy be the inexpensive part.

-- Jim from Heirloom Woodshop, custom furniture ,maker, woodworking school, heirloomwoodshop.com

Like was said above, get some quality paper. The cheaper paper isn’t as consistant on the grit. I have seen what your talking about even on my PC sanders and its always something clogging the paper.

-- Scott, South Carolina

Everyone so far has had valid points. I really agree with Jim, cheap power tools rarely do a decent job. In your case, it’s probably not all the sander.

I understand the budget issues we all face, but in woodworking, quality tools make a big difference. I’m not saying you have to buy Festool or Fein. There are a lot of good brands to chose from. I know Jim has had good luck with Porter Cable. I prefer Bosch. I have a 1/4 sheet Bosch that works great, and it wasn’t terribly expensive. There are several good brands. Obviously if you read these forums much, you’ll see everyone has a different opinion when it comes to power tools, or even sandpaper. It’s already been said here to check your paper. I’m having good luck with Klingspore. (They do catalog and internet sales) Norton and 3M are good, as are many others. It is not only the brand, but the type that matters. The “Box” stores are not always the best source for that. Check your local professional paint store and see what they have, or search online. They make different type sandpaper for a reason. Any manufacturers website explains the types and what they do best.

I’ll shut-up now. I hope some of this rambling helps.

-- Kent Shepherd * The goal is-----More Tools!

I’ve had good luck with the Norton 3x paper. In all honesty I’ve never had a truly bad experience with the cheaper stuff, it’s just not as durable (edges fray easier, grit wears off) and clogs up easier so you have to be more careful with it. If you decide it’s the sander, I can give a very enthusiastic thumbs up to the Ridgid, which I think was about $60.

One other thing to look at: If you’re really getting nasty marks, ie more than you think whatever grit you’re using should leave, flip the sander over and take a look. You might have picked up something that’s stuck in the paper. Or if you tried to sand a finish before it was fully cured you might have some spots of finish that gummed it up.

-- Steve -- University Heights, Ohio

As a furniture refinisher…swirls are caused by too a grit paper…AND…moving the sander too fast across the surface. The sander needs time to cover “its own tracks”. Moving the sander the distance of 6” in about 1 second shouldn’t cause swirls. Overlap each pass by half…keeping the sander level (meaning not tipping the sander to one side…”To make it cut faster”. I usually start with a 150 girt then to 180 for the final sanding…some times only the 180.

Going to finer sand paper will “polish” the surface making it difficult to stain. The 180 will leave the surface with sufficient texture for an even staining and finishing. Also if the surface is toooo slick and smooth you risk losing adhesion of the finish to the wood.

Bob