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Hi,

I'm to the point in my first build where I need to sand the guitar body to prep it for finishing. Since I have no experience or reference in using sanders from a prior life, I thought I'd appeal to the folks here for advice.

Thanks for your time.
Marc

I sand mine by hand. Sometimes with a cork lined block. You're most likely going to need to sand the rims and neck by hand anyway, so why not do the plates that way as well? Much quieter, doesn't pollute the air in your shop as much and encourages finer work at all previous stages. Plus there are things you can feel and hear when sanding by hand that you'll never pick up on using a machine, like a loose spot on your bindings.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

I recommend "Durabloc" sanding blocks and hand sanding.... It's easier/faster than you think when you progress through the grits and pay attention to technique.... Power Sanders can put you in a world of trouble in a split second....

Thanks

Once a guitar is together I wouldn't recommend a machine for sanding; you will not be able to keep planes flat
and once the finish is on you'll see ripples and dips.

If you're looking for a random orbital for other things I'd recommend a Milwaukie. I've used most of the R.O.
that are available and I've found Milwaukies to be one of the most durable. They also are variable speed
which is handy.

If you are inexperienced using a power sander could lead to disaster. Not worth the risk.

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http://goatrockukulele.com

If you are inexperienced using a power sander could lead to disaster. Not worth the risk.

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http://goatrockukulele.com

A finish sander is not something you want to scrimp on and like the others above I would use a sanding block unless you are willing to spring for a good one. A good one will make finishing easier and cleaner. A cheap one will make a mess of your project and poison your lungs. I would look at the Festool ETS 125EQ and/or ETS 150/3EQ. http://www.festoolusa.com/products/random-orbital-sanders They are the best in their class for dust removal, reliability, low vibration and resale value (in case you decide you need to sell them). Not cheap, but worth the money. You should try them out at a local dealer and see how they work.
If money was no object or I was in a production environment I would get the Mirka CEROS unit. http://www.mirkaceros.com/CEROS_home.html It has a brushless DC motor with a separate power supply. This makes it very small, light, powerful, quiet, super reliable and expensive. Most of the big factories (Martin/Gibson/Taylor/etc) use the air powered version of this sander.

I did sand 4 guitars by hand. On my last two guitars I discovered the joys of a good random orbital sander. I was very happy with the scratch free level surface I was able to get. I used it on the top and back, the sides and the neck. I ended up with a better more consistant surface than I was achieving by hand.

My only issue with the sander was that it took my hand two weeks to recover from preparing two guitars for finish, including leveling after 3 and 4 Zpoxy pore fill sessions in one weekend.

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http://www.Harvestmoonguitars.com

a ramdom orbital sander is nice to have for a good finish, It doesnt need to be expensive,IMHO, I have both a craftsman finishing sander and a harbor freight RO sander which I picked up pretty cheap, there is a harbor freight close to my house, I find I use the RO sander almost all the time...good sandpaper is always reccomended. On epoxy pore fills I sand the initial coat back down using 150 grit then swithching to 220 grit, on the second coat just 220 grit using the RO sander , takes only a few minutes, the final coat of epoxy I wipe a thinned mixture on with a cloth and hand sand with 400 and 600 so not to sand back to the wood.

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MK5acoustics.com

I would and do sand by hand. Almost as fast as power sanding. One exception is that I do some RO sanding on the plates. ALWAYS use sanding blocks, never use your bare hands. Cork lined blocks work for most sanding and softer blocks can be used for the finest sanding. I use cork lined blocks all the way up to level sanding the finish with P1000 and then softer foam rubber for wet sanding with P2000 before buffing. Sometimes hard blocks can result in deeper scratches even with the highest quality paper. The softer blocks for the final sanding leaves a very consistent scratch pattern for easier buffing.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

Thanks folks. Your opinions and advice is appreciated. This gives me great ideas on how to approach this.

Regards,
Marc

RO sanders don't leave a scratch free surface. In fact nothing leaves a scratch free surface. It's just that the scratches are smaller circles and random, but if you hold it up to the right light at the right angle you will see them. I am very particular about this stuff. All you can do is make sure that that you keep replacing the previous scratch marks with finer ones, until you can no longer see them, i.e. extra fine Menzerna buffing compound.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

Also level your epoxy with a well tuned scraper; much nicer than sanding.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

I use my Porter Cable Speed Bloc 330 all the time. Especially necks. It's great for sanding those scratch marks out of the headstock and heel transitions you always have after neck shaping. That seems to take forever by hand. Anytime something really needs to be flat I do it by hand.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I agree with all who say sand by hand, use the old Armstrong sander.

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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

It is true that power sanders can get away from you fast. And there be issues when sanding over two mated surfaces of different hardness (eg rosettes and top wood). Still, I prefer a good ROS. Like this one: http://www.amazon.com/gp/aw/d/B001B2EGJ ... 806&sr=8-2. Low profile makes it easy to handle. And it us variable speed. It's harder to use in the waist areas. But great everywhere else.

Mike

Let us not forget the ever handy burnished scraper either of course.
that's the real old school sander. Works great for glue.

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

I really appreciate everyone "weighing-in" on this.

Cheers,
Marc

When I bought a RO sander I thought power was great, faster, smoother.
Then my fingers began to "tingle".

I'm happily back to cork blocks, and I think, a better job with them.
My right arm is buff, too.

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very helpful to always have this in a back corner of your mind on finishing anything