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I'm thinking of buying a Wagner Safe-T-Planer and wondered how thin I could make the tops and backs before jointing, and my drill press hasn't enough depth to take a jointed top.

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Formerly JJH

I learn more from my mistakes than my successes

Hi John
I would recommend the Safe-T-planer for small shop use. I use the Wagner safety planer for all my tops and backs with great success. I take them down to just above whatever the final thickness is going to be. I then level sand/scrape before I join them. Once joined I do my final thicknessing with a ROS. For the top, I still leave it a little thick to compensate for the finish sanding once the body is joined.
Cheers
Mat

P.S. When are you going to post some pics of your 'UKE' ??

I suggest to keep the plates as thick as possible to glue up. This allows you the most adjustment for show and glue. If you can keep the plates as thick as the perfling strip that should be thick enough. I use a sander so I am afforded more workability. The biggest issue you have is getting the plates as flat as possible when gluing so you don't have to over thin the plates.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I also keep mine thick at glue up.It makes it easier to get the proper thickness throuhout when finish sanding.If you glue up too thin, you risk ending up too thin after the final level sanding.

How accurate is your jointing process?

Say you joint and leave a 0.020" height mismatch at the glue line... (which is pretty good)

If you thinned down to 0.1" before jointing -- and now you not have to sand off that mismatch.. you end up with a soundboard that may be as thick as 0.080" at the joint... and probably quite a bit thinner.

On the other hand.. if you initially only sand enough to knock off the big saw marks, knock down the fuzz, and flatten the plates a little.. you still have plenty of thickness to make up for slight glue line mismatches, scrapes, and dings that are bound to occur....

Just something to think about

John

im planing by hand and using a roping technique to glue the plates together so i just cleaned up the surface with scrapers and joined em at their shipped thickness.

It's a dance you have to do when you're using a Safe-T-Planer on a drill press whose swing is too short to allow thicknessing a joined plate. Go thicker and you have a lot of hand-planing/sanding after joining - go thin and you risk ending up with too thin a plate after joining and leveling. I used to give myself an extra .020" on spruce tops, because it's soft and easier to work by hand after joining than most backs, and closer to .010" on harder woods like rosewoods for backs. When gluing, I went to great lengths to get the seam flat.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

John: If your mismatch is .020 on one side the real mismatch is actually .040. Real easy to get into trouble if you don't consider both sides.Especially if you are joining plates that are thin.

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A person who has never made a mistake has never made anything!!!

John,

I've joined tops and backs at thicknesses very close to the final ones and as others have said you need to take care to keep the plates flat at the join. In your position with the Wagner Safe-T-Planer I'd probably make a simple jig that would do this for you with thin plates - you need a flat base and two long beams (slightly longer than the plates being joined) that you can screw/clamp down on either side of the join. I've had the basics of such a jig in my head for a long time to use with the hhg/tenting method and one day will get around to designing/making it - two raised beams that have a sort of lever clamp mechanism that means both beams can be lowered/pressed flat quickly with a couple of levers. Slide the plates joined by tape in the tent position into the gap between the raised beams, spread the hhg and then clamp down the beams - Bob's your Uncle . . .

With hhg if the join is not flat in places you can at a push melt the glue with a hair drier and push the plates flat - the jig would be a better solution though.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010