# Why use an Orbital Sander?



## danoaz (Jun 16, 2012)

So I don't have a buddy next door or someone to call and I am a complete novice as is evidence of this question. I see Youtube videos and so forth of people using orbital sanders and I don't get it. I was always taught to use the flat square vibrating kind and sand with the grain. Doesn't the orbital sander tear up the wood no matter what grit you are using?


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## Finisherman (May 3, 2013)

The key here is to use a random orbit sander. These machines create a random scratch pattern on the surface, rather than a consistent one. The human eye will naturally pick out a regular pattern, and since there isn't one, the scratch pattern become indiscernible. Just be careful to move the sander at a slow, even pace and be sure that there are no large pieces of grit under the pad. If you see "pigtail" scratches on a surface, this indicates that the machine was moved too quickly across the surface.


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## Loren (May 30, 2008)

Random orbital sanders remove more material faster so
you can get through a progression of grits faster. They
do leave little semi-circular marks though. The marks
may be removed by hand sanding for the finest 
work or work with stains where they would be noticed.


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## distrbd (Sep 14, 2011)

I have not had much luck with my random orbital sander,I need a lot of practice so I don't leave those swirl marks
I tried slow even pace like finisherman says,tried different grits of sandpaper but at the end of sanding with it I always have to use my 1/3 sheet sander to get rid of those swirl marks.
I know experienced hobbyist and professional finishers use them all the time but for me,my 1/3 sheet Makita does the job better.


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## Dusty56 (Apr 20, 2008)

*distrbd*, have you checked to see if the "brake" is working properly on your ROS ? If it is, you shouldn't see any swirl marks at all. If your sanding disc is spinning in a consistent circle,and at a high rate of speed, then the brake isn't working. The other possible reason for seeing any marks at all would be by skipping too many grit sizes between coarse and fine. 
I always use my ROS for removing blemishes quickly, and then switch over to my Porter-Cable 330 Speed-Bloc finish sander. That baby purrs….so smooth and zero vibration : )


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## distrbd (Sep 14, 2011)

Dusty,this my ROS:








As far as I know it's working flawlessly,I also use it to buff my car with it,I wish I could blame it on the tool but as you know ROS are not as easy to use as regular vibrating sanders,I just haven't found the knack of it yet.


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## Dusty56 (Apr 20, 2008)

I have the 5" Porter-Cable ROS's from a few years ago…make that about 10 years ago now that I think about it.
I can see where you might get swirl marks from that model while trying to balance it and move it along at the same time. Reminds me of a grinder / buffer, more than a sander, but I can remember Norm Abram using a similar tool to yours.

This is the "brake" / belt that I was referring to earlier that fits my sander and others. It is located beneath the sanding pad disc.
http://www.amazon.com/PORTER-CABLE-BELT/dp/B001S3ZXYG/ref=sr_1_3?ie=UTF8&qid=1378003195&sr=8-3&keywords=porter+cable+333+sander+parts


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## MarkTheFiddler (May 29, 2012)

I used to use the sheet sanders. I gave every single one of them away. I use random orbit sanders all the time now. I move the sander slowly across my wood. No more than half an inch a second. If you press down, you get swirls. If you angle the sander you get swirls. Just use your hand to steer the sander. Don't press down.

The only thing is, I used to see a bunch of swirls with the sheet sanders. I don't see any with the ROS. The sheet sander was a pain to change paper with. The ROS with hook and loop changes out fast. It took 3 times longer with sheet sanders.

I make a few passes with 40 grit if needed. 80 if needed. Well planed wood, I start at 150, 220, 320 done in one pass each.

I used to dread sanding. I love it now.

Best of luck.


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## MarkTheFiddler (May 29, 2012)

Ahh - the picture. I'm definately recommending the palm sander ROS models.


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## Loren (May 30, 2008)

Read this:

http://www.woodweb.com/knowledge_base/Stroke_drum_and_widebelt_sanders.html

and this:

http://www.woodweb.com/knowledge_base/Stroke_Sanders_and_WideBelt_Sanders.html

These threads deal with wide belt machines, drum sanders,
orbital sanders and stroke sanders. The input is from professionals.

Sanding is a huge time-suck in building work for clients ,
who usually expect a simulation of perfection, no
matter what the price tag and don't care how much
time it takes or what the machinery investment is.

Machine marks are most quickly removed by heavy sanding
machinery or by cross-grain sanding with a random orbital 
sander. The reason these sanders are aggressive is because
they tear the wood fibers from the side. I have never
found them to not leave marks, but the marks can
be reduced by meticulous compressed air blowing and/or
tack cloth cleaning between grits.


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## Loren (May 30, 2008)

Oh… and to answer the question of the thread title:

*To save time and sweat.*


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## distrbd (Sep 14, 2011)

Dusty I'll have to check it out.
Mark,now you put that ROS palm sander picture in my head and I just can't shake it off,Home Depot here I come.


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## Loren (May 30, 2008)

Here's another thing:

Those 1/4 sheet sanders are orbital sanders. They are
not random orbital sanders however and they are
not as aggressive. I believe the orbital pattern tends
to be smaller than the round type and thus the
scratch pattern isn't as obvious.

Festool sells random orbital sanders in the 3mm orbit
and in the 5mm orbit. I have a 5mm and it is aggressive 
and leaves marks. I am seldom perfectly hygenic with
orbital sanding however and do not always blow/tack
cloth wipe thoroughly between every grit.

You can get 1/2 and 1/3 sheet sanders with linear
motion. They approximate hand sanding in a handheld
power tool the best I think.


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## GaryC (Dec 31, 2008)

I use the ROS almost every time. I have never had any problems with swirls. But, even tho I use the ROS, I always finish sand by hand.


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## MarkTheFiddler (May 29, 2012)

Ken, I honestly believe you will be very happy with it. I bought a rigid variable speed model and it broke within 30 days. HD replaced it with the Dewalt variable speed for no up charge. I have used it for over 100 hours without any issues.

I have used the skil ROS and it's not bad but the extra bucks spent on the Dewalt are worth it in my opinion.

I read a review on the Dewalt ROS and folk weren't impressed with the dust collection. I have heard good things about the porter cable and Bosch ROS palm models. Have fun, make slow passes and watch your sanding woes go away.

HD sells the diablo paper. Not bad but the vent holes are very small. Even though its expensive, I prefer woodsmith brand at Lowes. The paper never seems to wear out!. Stay away from garnet. It's cheap and doesn't last. You will be prone to make the paper last longer. Both the diablo and shopsmith are long lasting.


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## distrbd (Sep 14, 2011)

Danoaz,I hope you you forgive me for hijacking your thread,it was not my intention,but looking at the responses you got,made it a good thread,there's a lot of wisdom here.
I'll stop posing and may start a new thread later .


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## danoaz (Jun 16, 2012)

@ distrbd - not at all. As usual the woodworker's society has not disappointed me with opinions and information. Thanks guys and gals.


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## gfadvm (Jan 13, 2011)

danoaz, ROS are available with several different orbits. 3/8, 3/16, and 3/32". The tighter the orbit, the less swirls.

Also, tilting the sander and sanding with the edge of the disc will guarantee ugly swirl marks.


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## 111 (Sep 2, 2013)

I also believe along with a little finesse and technique, that quality paper makes a difference.


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## a1Jim (Aug 9, 2008)

No contest ROS's work much better than 1/4 sheet sanders. If your tearing up your wood when using one you have the wrong style ROS or your using to course of sand paper.
I have 7 or 8 ROS's the one I like best is this guy.

http://www.homedepot.com/p/t/100609940?productId=100609940&storeId=10051&langId=-1&catalogId=10053&ci_sku=100609940&ci_src=17588969&cm_mmc=shopping-_-googleads-_-pla-_-100609940&ci_gpa=pla#.UiS-jtKmh40


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## AlaskaGuy (Jan 29, 2012)

Why use an Orbital Sander?

Because I can sand face frames, cabinet doors where 2 pieces of wood come together at 90 degree angles (or other angles) without leaving cross grain scratches.

On big pieces of plywood I still often use an 1/2 sheet sander.


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