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You guys probably all do it. Masking tape and super glue.I've seen electric builders do it for fixtures for routing. I have a little baroque guitar in A, that will be an 8 string uke, and it has a very thick back of spruce with a fancy inlay on the outside. I switched to making it Padauk instead. I still have a lot of it! So the one side was smooth, and the other not. I glue them on, and put it in the vise.

VERY easy to thin down to 1 1.5mm or so.



So I thought it would be great for ribs. The Padauk is a pain to plane down. Ribbon figure. If you plane end to end, it will rip out. This rib has 5 ribbons! Planing on an angle will snap thin stock for sure. Masking tape, and CA, and it works great. Just 1/8" hardboard under it. I can measure it with my thickness gauge, and subtract 3mm. This side has the saw marks off, and it is fairly even in thickness. Smooth it up, and I'll turn it over.

I even turned the blade around so it is more like a scraper. That helped. Less chance of tear.

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Why be normal?

I don’t use it much but it does work good.


Steve

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Steve Smith
"Music is what feelings sound like"

I think I'm thick....what's the technique being applied?

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Peter Havriluk

I think Ken is using the trick of putting down masking tape on a surface, putting masking tape on the bottom of a part to be planed, then supergluing the two pieces of tape together, so the part stays put with no clamps. Is that right, Ken?

Yes that is what he is doing. I simply use double stick tape. I have never tried this trick before but many do.

It's a great way to plane thin pieces of wood but doesn't allow for easily checking and flexing as you go much. Am I wrong?

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Hutch

Get the heck off the couch and go build a guitar!!!!

If you want to see a demo of this method check out our own Andy Birko of forum sponsor Birkonium sharing how he uses this for CNC work holding. Episode 2 of the OLF Roundtable (skip to 49:00) - https://youtu.be/uvLJjLvudjU?si=lGQoNGbJHleu1tJf

Brad


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Brad, I think that is where I first saw it. I tried double sided tape, but it was what I had around: window film stuff. The idea of smoothing both sides of the tape makes sense. With double side tape, you can't smooth EITHER side down.

Hutch, You do bring up a great point. For the back, flexibility doesn't matter. But it was FAR easier to glue it on, and plane 1-4mm of rough sawn stock off, than to try to clamp it to the bench or something to plane each half down to 1.5mm.

For ribs, 1.7 mm is about as thick as I go. They start to feel flexible about then. Usually not more than 1.5mm; but in areas with less curve it could be thicker. Going to 1.0 or less doesn't scare me: in places where the curve is tight: like violin corners, or the really tight bend on the LessPaul cutaway.

If the stock is not on the quarter it could be thicker. Flamed stock is tricky. It is easier to bend thin, but it could snap easier too. Bend thick, and hope it just cracks, and doesn't snap?

So I can pick a starting point. After that scraping stock off some areas that might need it isn't as much of a problem, and doing the entire piece. Just scrape straight, and away from the clamp!

I usually have wood I cut for ribs. One side is planed smooth, and the other is sawn. It could be fairly even. It could be really gnarly. Even the 1/8" piece of Walnut I have cut up as a back and sides for the Vihuela is fine almost as is for a back, but it actually measures 3.5mm, and that is way too thick for sides. If I can plane 1.5mm off, not having to worry about catching the plane on the way back, and snapping the sides; or splitting it with clamping pressure; it's a good thing.

I've decided to make the linings stronger. I always bend solid pieces, about 2mm, that seem fairly strong. But I think I will bend 1.5 mm or so ones, and laminate them. And then taper them down to nothing. Easier to bend, and will be stronger, and create less of a stress point?

I can thin a bunch of wide stock, and then slice it to the right height.

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Why be normal?

I wish I had been aware of this technique when I was building mandolins. I always clamped one end to plane the sides and then spin them around. This would have save a lot of time and probably give better results. Now I have a thickness sander

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Hutch

Get the heck off the couch and go build a guitar!!!!

I don't see an advantage compared to double sided tape. In fact, the CA technique will leave glue residue on one surface which may make the backing surface a one time use.

Barry, you put blue tape on both surfaces and CA between.

I use this extensively in CNC work and you can hold any odd shaped thing down and still cut it with considerable force and no movement.

There is great holding strength laterally, just none vertically which means you can pry the piece up with relative ease. Check the video above for a demo from Andy.


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Yes, this technique made double-sided tape all but redundant in my shop. Cheap and one less type of tape to buy and keep track of.

In repair this is very useful for attaching things like routing templates and drill guides to delicate finished surfaces like guitar sides - you can use your favourite lower tack tape and still get sufficient holding power. I use it to handplane wedges to zero thickness at one end for fretboard extension shims during resets, or to make custom neck shims for Fender-style guitars. The easy removal means less chance of damaging the paper-thin end of the wedge.

In building I like using the technique so thin stock can be securely held to a backer board and sent through the planer or have some other machining operation performed.

Yes, you could use double stick tape for many of the same purposes but I’ve never found one that is as fast, gentle and residue free to remove - and the masking tape and CA is always at hand on the bench. With double stick tapes I found myself resorting to wicking naphtha underneath to soften the adhesive at times to facilitate removal from delicate areas. This is less fussy.

Josh, thanks for explaining it clearly. I do see the advantages. I agree that dealing with removal of double stick tape is messy and difficult.

I remember someone here passing on this tip and I've never used double-stick tape since. It’s so much easier to deal with. Please note that I mainly use this for holding down templates for routing and it is plenty strong enough and I never had it fail on me. I'm using regular 20 CA for this.


Pierre
Guitares Torvisse

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Pierre Castonguay

News flash: Old dog learns new trick.

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"Act your age, not your shoe size" - Prince

Yesterday I was thinning the belly for the little "uke," The first split in pieces sitting in a box waiting to be built. No strength without being glued around the edge. About 2mm thick. I can still salvage the rose. The stock wasn't that thick, and I need to check stiffness fairly soon.



I'm at 2.4mm here. The big plane works the best. It is like the blade is welded on. It is nice to have everything about ready, so I can get it together fast, and then work on finish. It isn't good to have things break before you even use them!

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I'm not going to say this method has revolutionized my repair work, but it has reduced setup times and enabled me to be more creative in my routing. I use a cheap stool to tape/glue my guitar bodies down to use as a platform when using a Dremel. I did a some roundover work on a Tele awhile back, and the other day I needed to rout a P-bass for a new pickup. I didn't have any 5 string routing templates, so I covered the body with tape and then taped/glued some paint stir sticks to set stops for my Dremel jig. Talk about easy. The stool is light enough I can just move it around to see better, or vacuum chips. I can see this is going to be a big help in the future with the projects I have lined up. I should have taken a photo of the body on the stool - next time. Anyway - here's the result.

https://imgur.com/a/A4KeHlw

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"Act your age, not your shoe size" - Prince

A turntable from a stool, masking tape and CA. And a fixture too? Well done.

I see people on youtube planing sides for violins and the are flopping around, catching on the plane on the way back. I tell them masking tape and super glue.
They don't hear me.

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Why be normal?