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That´s actually a nice idea Clay - the kind i usually overlook. Thanks!

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member of the guild of professional dilettantes

I found this video that seems to explain it well. https://youtu.be/F4X6Ezi8UW8


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Resurrected a 7 YEAR OLD thread.

Yeah and 7 years ago I see I commented. I have since changed my ways and have gone back to my clamping jig. The only top joint I have ever had failed was one done with the tape method so I will never use it again. And it's so simple to set this jig up. Just 3 sets of wedges, a back stop and something to hold everything flush from the top.

FWIW, I still prefer the LMI jig, but the tape method is a good skill to have in your quiver. I recently had to add two 1/2” ears to the lower bout of a cedar top and mad rose back set that we’re both perfect for a 15.5” body but too narrow for my 15 5/8”. The LMI jig won’t work for that kind of situation.


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I use tape in conjunction with a clamping jig. I like the way you can tent the two pieces after you tape one side. Makes running a bead of hide glue down the joint quick.

I never totally trusted just the tape alone although I know a lot of good builders swear by it.

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

My fave is 2in wide u haul brown packing tape , in conjunction with vln/cello making alum ltweight clamps from condit mfg. These clamps are perfect as the end caps swivel (similiar to japanese brass clamps) and with a flat 2in w scrap clamping jig laid transversely on a flat melamine board it keeps everything flat, and glue squeezeout , s cleaned off the melamine

I used tape for about 10 years, never had one fail but went to the LMI jig and never looked back.

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Steve Smith
"Music is what feelings sound like"

I use the Scotch 233 as per Mario and others. Just the right amount of stretch and stickiness and never had a failure. Touch spruce!

I still tape and hang tops when I have enough thickness to sand out any small misalignment, but recently when joining a back that was close to final thickness I used the tape method and the go bar deck and used go bars across the joint to hold the pieces in perfect alignment. I also used this setup to glue on the back graft.

There are a lot of good opinions here already. I use green body shop tape purchased from O'Reillys Auto Parts. It stretches and has a strong recoil. I also use the same tape for gluing bindings. Spruce fibers can lift up so I heat with a hair dryer as I remove the tape. The tape releases easily. I think I learned about using tape on this forum years ago.

Something to think about. Titebond recommends 100-150lbs/sq inch of clamping pressure for softwoods. Tops of course are long thin lines so it's probable not a fair assessment but a 20in long top board at .1in thick is about 2in/sq.

I think the key is if you use the tape method don't use too much glue and maybe do a rub joint first before taping.

been taping for 20 years
the simple fact is your joint , if it isn't perfect no clamp will make it better

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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 heard that one of the benefits of hide glue is that as it dries it pulls the joint tighter (again, assuming the joint was well made to start with).

John, what glue?

I’m comfy using the tape method and HHG, but not titebond.

After I cut out the soundhole, I break the disc to see what happens. I’ve had a few TB and tape open right along the seam, so I don’t trust it. Never to my knowledge has a top seam opened, but I stopped using that method with TB very shortly after I started...

The first thing that came to mind when I read the term "Tapers":

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

That sure is age old wisdom and has been done on thousands of Spanish Classical guitars for sure. But I have my doubts. What it could indicate though is that a braced top doesn't really need a very strong center joint? Like John said it's the fit that's most important the clamps just hold it in place as the chemistry of the glue does it's thing. I use HHG for tops now but still clamp.

The failure using tape that I had was with Titebond.

I just put two guitars together using peones to join the top to the sides with HHG. I dipped one peone in glue and simply dropped it onto another piece of wood and let it dry. Next day I took it apart with a chisel and a hammer blow and the joint held but the wood ripped apart.

So in the end it could just be that using HHG is good enough.

A video of tapers in action:
https://www.youtube.com/watch?v=zJm6nDnR2SE

And keep in mind the closing statement; to paraphrase, If you don't take any risks ,like tapers, you might just fade away.

I gave a live demonstration of HHG rub joints to my local woodworking club last year. It was really something to feel how strong those joints were after just a few minutes. And the gelling of the glue is not the only time sensitive thing to watch with HHG. It dries (in other words, loses water) faster than you would anticipate after working with an aliphatic resin. So, yes, the “suck together” thing is useful.

Having said that, you really do need to make sure the parts are touching each other, surface to surface, in order for the “suck together” thing to work with HHG. Some joints are sprung or otherwise tensioned, so you really need to clamp in order to make sure you get a good joint.

I use rub joints all the time. The head I glued on yesterday was just: glue on both sides, rub together, check to be sure that it is on in the right place (a surprisingly easy step that I HAVE forgotten to do at times) and then let it sit there. After 15 minutes or so, I scraped off the gelled overflow. An hour later I was carving the bottom edge of the head to blend with the neck with my knife.
How can you possibly clamp a v joint anyway?
A while ago I glued a bass bar in a violin with 3 clothespin clamps just to keep it from falling. An hour later I was clamping it on the ribs to see how much tension the tapered ribs gave it, and to check the basic tuning of the belly.
Hide glue is fast.
I WILL clamp that belly overnight or so when I get around to gluing it.

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Why be normal?