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As mentioned in a few threads, the Gilbert disk sander, which mounts in your drill press, is very handy. It's nothing more than a big, well, disk, that accepts PSA sanding disks, and chucks into your drill press. You can buy one by contacting Greg Martonis at Gilbert Tuners. They are not advertised on the site, but if you email him he will make you one.

I have 2. I keep 120 grit on one, for fast stock removal, and 320 on the other for fine sanding.


I'm going to post several examples in this thread. Please don't post to this thread until I am done, thanks!

Also, I don't think there is an original thought of mine in this thread. I got most of the ideas from David Schramm, and the rest from Roy Noble.

This first pictures shows the sander in my drill press, and a simple holding jig I made. The jig is just a piece of maple, with rosewood glued to it to hold small parts. I just used superglue to glue this up. That way you can have a jig built for a specific purpose very, very fast.

I use this jig to thickness and shape nuts and saddles. I will only show doing a nut, the saddle goes the same way.

Here I am thicknessing my nut. i start at 120, and switch to 320 grit when I get close to final thickness.

p.s. Note that all pictures are taken with the disk turned off. That's for my safety as a photographer.

Also note the direction the disk spins. I have that nut positioned so that if it catches, it'll fly away from me rather than into my face. I've launched a few pieces, and while it is nothing like a table saw kickback, you wouldn't want to take it in the face.


Okay, so here I use a half pencil to mark about where I want the strings to lie.

Now I use my handy angle vise to take down the top of the nut, and impart the back angle at the same time. Of course you will need to do some hand work to finesse the shape, but this gets you in the ballpark very fast. I go to within about 1mm of the line, as of course you need bone above the bottom of the strings.



edited to add: note that the nut is on the UNSAFE side of the sander in this photo. I wanted to show the angle adjustement for the vise. If the nut escaped from the vise, it would be launched into my face or body in this photo. In reality I always sand on the left side of the disk.rlabbe38533.502974537

This next sequence shows how to make veneer with the disk. Here I am slicing a pen blank into pieces for a rosette. I'm using a very powerful and accurate resaw called RogersArm. Its rated at 1 bp (bicep power).

It's pretty much smooth enough to inlay, but I was chicken and sawed them thick to allow for mistakes. So off to the drill press we go...

And I sand them with the same jig I used for the nuts and saddles.

Guitar elves sneak into the shop during the night, and the next morning a rosette is inlaid and ready to go!

Finally, here I am using the disk to flatten the top of a scarf joint after gluing it up. Sure, a plane works too, but this is pretty foolproof. I'll reach for the plane if the disk is not chucked into the drill press, but if it is chucked I go this way. Just whatever is faster at the moment.

I use the plywood to get the neck off the table so it'll lie flat. It's not apparent from the photo, but I used some double sided tape to hold it on, because the piece underneath is not that big. If anything tips, you could cause a jam and launch the neck across the room. In general, anything you sand with this jig had better be wider than it is tall, or otherwise you are courting disaster and injury. A nice stable platform is required to keep things safe.

Anyway, I use this disk all the time. Before I had my thickness planer, I even used it to thickness back and sides, though that is very unpleasant (slow, very dusty). I still use it to take my bindings to final dimensions. I also use it to bring my braces to final thickness. Since I don't build a lot, it's faster to leave 120 grit in my thickness sander, take the braces down to close to their final dimensions, and then come over to the drill press to take them down the rest of the way and impart a smooth finish on them at the same time. For me that is faster than changing paper. If I was doing 200 braces at a time, I'd change paper on the thickness sander.

Okay, I'm done, I'm sure you get the idea of what this tool can do. Hope it was helpful.

rlabbe38533.3923263889

p.s. How did I make that half pencil? With the disk sander, of course!

[QUOTE=rlabbe] Guitar elves sneak into the shop during the night, and the next morning a rosette is inlaid and ready to go!

[/QUOTE]

That is a beautiful Rosette! Can I borrow those elves?

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

Excellent tutorial! Thank you. Gives me lots of ideas for the sanding disk I have.

Did you add a black purfling line between the rosette pieces or is it something else? Awesome rosette!

Thanks for the great information.

Jeff

[QUOTE=Jeff Doty]Did you add a black purfling line between the rosette pieces or is it something else? Awesome rosette![/QUOTE] Yup. I cut the veneered strips into trapazoids, and glue them one by one onto a sheet of carboard, with purfling strips in between. Use a router to turn it into a circle, cut it off the cardboard, inlay into soundboard, rout an inner and out channel for the purfling, and inlay the purfling.

Can I add my nomination for the Gilbert type sander as the tool of the decade!

I've used some very similar (my engineering dept at work made mine) for many years and all the thicknessing on my first dozen or so guitars was done using them. Until my better half bought me my Jet 16-32, sides/backs/tops everything was sanded to thickness with these. Like Sylvan, (if he does it it must be right, OK) I too have a separate pillar drill dedicated to my sanders. If a gun was held to my head and I was told I could keep the Jet 16-32 or the Gilbert type sanding discs, it would be no contest, I would keep the Gilberts. The use you can put them to is only limited by your imagination.

Great tutorial should be added to the tools and Jigs section and every new (and old)luthier made to look at it before being allowed any where near any decent mahogany.

Colin

Colin S38533.5213194444

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Thanks for the post Roger. I agree it should be added to the jigs section here on the OLF. I purchased 2 of these last week from Gilbert Tuners after you and Sylvan recommended them. They were a pleasure to deal with and I had my order in just a few days. A few ideas I have for them include 1) assist in sanding a curved volute, 2)attaching sandpaper on the sides to use much like the Luthiers Friend sanding station for thicknessing binding etc., and 3) attaching a buffing bonnet to the bottom for bridges and other small pieces. I definitely think they are going to be worth the money. By the way, the price was $50 a piece, not bad at all for what will be a multi-purpose jig. Alnost forgot, really nice rosette Don A38533.5400925926

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Don Atwood
Arlington, VA

Don, as for #2, I'm not sure I understand the need for that. You can already thickness binding, just set the disk low to the table and run the binding underneath.

I left out a couple of picture I intend to add tonight. I build classical, and I use the disk sander with a jig and the angle vise to create the bevelled edges on the wings of the bridge.

Some people recommend cutting out the center of the sanding disk so there is only a 1" circle of paper around the perimeter. I haven't found that particularly useful, but can see how it may help with things binding up.

Okay, here is a classical bridge taped down to my high tech bridge sanding jig. It's just two pieces of wood superglued together.

Here I have put it in my angle vise. A few seconds of sanding and I have a perfect bevel.

Flip the jig 180 degrees, and do the other side.

One other quick suggestion. Cut a piece of leather in the shape of the circular top of the sander. Cut a hole in the middle and place it on top of the disk sander. Now, with a little compound you have a terrific honing device so you can keep your chisels razor sharp with very little effort. I set up an $80 Delta drill press with this dedicated tool. Great for all of the above ideas and, it is my very useful for keeping all of my tools razor sharp!

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Sylvan
http://www.wellsguitars.com