orbital sander or a random orbital sander?

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James Mc
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orbital sander or a random orbital sander?

Post by James Mc » Sat Dec 13, 2008 7:14 pm

Hi All
I’ve decided that while doing things with hand tools is nice, doing everything by hand it just too time consuming. I’ll be building a few more once the current projects are done so I've decided to lash out on a couple of power tools. I don’t seem to be capable of drilling a hole square to the timber with the old brace and bit so first on the list is a drill press. The other item I could do with some advice on, sanding everything by hand just isn’t working for me so a finishing sander is the other tool I’m after. Strange as it may seem, in years of engineering work and furniture restoration I’ve never once used a random orbital sander, so which will serve my needs best, an orbital sander or a random orbital sander?

Cheers
James

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Kim
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Post by Kim » Sat Dec 13, 2008 7:22 pm

Random orbital is the best bet James. Orbital is very old tech and thankfully you would find it difficult to come by one now days as they where pretty hopeless.

Cheers

Kim

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Post by kiwigeo » Sat Dec 13, 2008 8:27 pm

A bandsaw is more useful than a sander.

My only large power tools are a drill press and bandsaw.

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Post by Stu » Sat Dec 13, 2008 10:32 pm

A random orbital sander is the go for a flatter sand using a hand held machine.
More commonly known in the industry as an oscillating orbital sander.

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Allen
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Post by Allen » Sat Dec 13, 2008 10:44 pm

It's possible to find sanders that do both orbital and random, albeit they don't do either well.

Orbital sanders are designed to remove material. They do this very well, and they are what I use every day to take paint off metal prior to metal work.

Random Orbital sanders are designed to refine a surface, and are grouped into 2 main categories that you would consider fine and coarse. It's all got to do with the amount of movement that is designed into the sanding pattern.

I'd recommend a random orbit finish sander (fine pattern) for all things Luthier.

I'd also recommend a fairly firm backing pad for the sander. You don't want it rock hard, like you'll find on cheaper models though. Try and find one that you can vary the speed on. This can make a heck of a difference in how effectively you can sand a surface. Most times flat open is not the best choice.

As for brand, there are heaps to choose from. For electrics I've only uses Festool, but they're obscenely expensive here. If I had an air compressor at home, I'd go with a pneumatic one. There are even more choices there, and most are very good, for far less money.
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Stu
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Post by Stu » Sun Dec 14, 2008 12:24 am

From what you mention here Allen, it may be worth stating your
main useage of sander as well.
As far as sanders go, there are differing types of oscillating orbital diameters to take into account.
As a Panel Beater , we used a larger diameter of oscillation as it tended to take the bulk of material away alot quicker.
Once we got to the primed stage , which entered the realms of the Spray painter, the festool and Dynabrade units were of a tighter oscillating pattern as to take less bulk away but also give a smoother finish prior to the first base coat of colour. These would also be used when de-nibbing
clear coat with from 1200 up to 2000 grit, prior to buffing.

For roundovers , you can't go past a velcro backed foam adapter pad known as a hookit backing pad. This would allow you to follow the rounded undulations of a guitar. (albeit more commonly found on an electric carvetop .) This minimised the grading marks similar to the edges of a 50 cent coin.
As Allen stated the best tools out there are Festool electric orbitals and extraction vacuum units (and Dynabrade air assisted), but they are very expensive, but in the long run will outlive anything else.
.

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Post by Hesh1956 » Sun Dec 14, 2008 12:51 am

I love my Festool ES-125 5" ROS and when I pass a guitar onto a pro finisher I use this ROS with 220 paper for the final sanding. Two finishers have asked me if I use a ROS and if so which one because they say the surfaces that I get are flawless.

Festool I think, but I am not sure, also makes a larger line of sanders that can do either ROS or O sanding and as such can really remove stock fast if you want them too.

I went through 3 ROS's before I got the Festool and the difference was incredible. I won't even touch the other ones now and they were much nosier too.

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Post by DarwinStrings » Sun Dec 14, 2008 12:51 am

I am with Kim on that, I bought a Random Orbital as a extra sander but after using it I don't pick up the Orbital anymore.

"De-Nibbing" sound like a interesting pass time Stu. I will be looking for a "Hookit Backing Pad" now, nice tip, cheers.

Festool rhymes with drool if you're on a low budget but if not, go the green and grey.

I also have one of those Triton Random Orbital attachments for a angle grinder for some work I do with N.T. Ironwood Branches. They are cheap and they rip, but don't be tempted it will eat a guitar.

Jim

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Kim
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Post by Kim » Sun Dec 14, 2008 1:30 am

Toejam wrote: I also have one of those Triton Random Orbital attachments for a angle grinder for some work I do with N.T. Ironwood Branches. They are cheap and they rip, but don't be tempted it will eat a guitar. Jim
Jim I have one of those suckers as well, and your right, they would eat a guitar. But if you want to remove material really fast eg paint on weatherboards etc, they are great and do have a place in the workshop. Only draw back is the hammering they give the bearing in your angle grinder, flogs them right out, but then you get that on the big jobs. 8)

I have an old festo RO sander, they are that good that when they changed their name to festools, they kept the design of the sander pretty much the same. For a company at the cutting edge of R&D that about says it all.

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James Mc
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Post by James Mc » Sun Dec 14, 2008 2:57 am

Thanks all
I've done some research and an Ingersoll Rand 150mm air powered beast is the one for me, seems to do everything and a nice low noise rating. It’ll tax my little compressor to its limit, but I can always have a quick swig or two while it catches up.

While I was looking to see if there was an interesting used alternative on ebay, I came across this table sander? I looked at the photos and couldn’t figure it out, I tried turning my monitor on its side, didn’t help. So if you’re tool curious and think you can figure it out here is description and then the link. It was at a cool $10 but a week to go. If anyone knows how it works… please explain.



UP FOR ACTION I HAVE THIS TABLE SANDER. I BOUGHT IT TO RESUFACE A COUPLE HUNDRED DAMAGED HARD WOOD TABLES BACK TO BARE TIMBER TO BE BOUGHT BACKTO BRAND NEW. IVE SANDED DOORS AND OTHER FURNITURE I MADE . NOTHING ELSE LEFT TO SAND SO ITS GOT TO GO I HAVE OWNED IT FOR20 YEARS & ITS NEVER LET ME DOWN I HAVE APROX 8 BELTS 40 80 120 GRADE SOME USED SOME NEW THE SET UP I HAD WITH THESE BELTS COULD SAND 2100X 1800MM WITH LONGER BELTS YOU COULD EASLY SAND 2400 EVEN 3000mm. THE WORK TABLE IS FULLY AJUSTABLE AND THE WHOLE THING IS VERY EASY TO USE ,IT ALSO HAS A DUST EXTRACTION UNIT THAT RUNS OF A PULLEY FROM THE MAIN MOTOR YOU CAN STOP THE FAN BY REMOVING THE BELT ITS A SIMPLE DESIGN THAT WORKS WELL I NEVER USED A DUST BAG & I DONT HAVE ONE

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... 0349442993

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Allen
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Post by Allen » Sun Dec 14, 2008 7:37 am

It looks like a stroke sander to me. The belt is very long and rotates at a slower speed. The belt sits over the table with the grit to the outside. You place the item to be sanded on the table, then use a wooden caul to gently press the rotating belt down onto the piece you want to sand. Good for a cabinet maker, but pretty well useless for luthier.

Back to the random orbital sanders. You can get the softer foam interface pads in different densities to aid in finish sanding. they are about 1 cm thick and have one side covered in fuzz, and the other with the velcro. They are used for fine finish work. Good for not marring the surface by build up on the sandpaper. You have to be careful of their use when you are near an edge, because they can roll it over very quickly if your using too coarse of paper.
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Post by DarwinStrings » Sun Dec 14, 2008 10:33 am

True Kim, if you have one you need to look at 4inch grinders as disposable. I keep a few of them now to save changing the tools I use with them and at $100 each for Makita they are a very low cost and versatile tool.

This might help with a Stroke Sander description James.

Image


I also found this Allen and your comment came to mind, I guess this guy had made an error while making the back for his guitar and needed to remove it to put a new one on.

Image

Jim

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James Mc
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Post by James Mc » Sun Dec 14, 2008 10:59 am

cool... I've used something much like it to put the grain on stainless steel and no way in hell would I be putting a guitar under one of em.

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Allen
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Post by Allen » Sun Dec 14, 2008 11:55 am

I suppose if it was some micromesh belt, and some very deft use of the caul, it should work on the flat surfaces. It looks like he's got some sheep skin for an interface pad on the sanding caul. But damn, you could do a lot of damage quick smart. :shock:

I'll stick to my little Festool and hand rubbing thanks. :D
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Post by Hesh1956 » Mon Dec 15, 2008 1:20 am

Man I wish that I had had one of those stroke sanders in my original bathroom shop..... :D

That would certainly make quick work of................ sanding a guitar..... :D

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