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It lines up perfect, but when i put the clamps on it slips back.

Also, I plan to use hide glue. Any advice?

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Pat

PVA is the choice here. Lots of open time to get the clamps set...

As always, pictures will help you get a better answer. I like to use hide glue for this repair. It's invisible and reversible. After a warm water cleanup it's easier to do any finish repairs as needed. I like to "clamp" with that clear plastic stretch wrap that comes with a handle. It conforms to any shape and you can wrap it in more than one direction. I just make sure that I preheat the parts I'm gluing and that everything is well lined up to begin with. An extra pair of hands is good here.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

I have a special caul for this. I use HHG or epoxy for these repairs. It depends on the amount of cross grain.

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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

jig - most of us make a shop-made jig to hold everything in place and apply clamping force in several different directions at once. Here's ours that Dave Collins designed - works perfectly every time!

https://www.youtube.com/watch?v=D6lzTM__Yrs

I like that one, Hesh!

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

I'm surprised by the calls for HHG...

John, got a pic?

I was thinking to go hide because of the quick grab. I was thinking too get it all in place with moderate pressure until it grabbed and then increase the clamping pressure. But, it looks like everybody uses some sort of jig. Hmmm..........

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Pat

I'm a little surprised at the HHG call as well. Seems to me that HHG is great to use if this is a repair that may be worked on again by someone else but to me....if I fix a headstock break, I do it once and it doesn't need it again. It should be a permanent repair.Epoxy is the way I usually go with headstock reattachment and a jig.

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Blue Ring Acoustics
blueringacoustics.ca

The clean up for HHG is very easy and doesn't affect the finish like epoxy. It also leaves a very thin glue line that shrinks as it cures leaving the least visible repair. Take a look at the David Collins tutorial that Hesh linked. (That's a good looking simple jig, Pat.) I would only use epoxy if the break was ragged with missing pieces.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

There is no single glue choice that will always be the best choice for head stock breaks. Instead every job has to be evaluated on it's own merits and with keeping in mind the specifics of that break, guitar, client, etc.

HHG is a great choice when and only when one is tooled up to use it properly. If you looked at the link that I posted you will see our version of a head stock jig. With this jig we can have all clamps in place with appropriate levels of pressure in 10 seconds or less. This makes HHG an option for us.

Without a jig some breaks will require fumbling with other clamps, etc. and one may not be capable of getting everything in place in say 20 seconds or so. When this is the case Titebond Original may be a better choice due to the longer open time.

As mentioned above epoxy is great for ragged edges that don't fit perfectly or where material may be missing. It's not a first choice here by any means but there are times when it's an OK choice such as inexpensive instrument, a joint that had been messed with before coming to us, and poor fitting parts.

When it comes to repairing head stocks servicability is not a concern, or it should not be if the job is done correctly making servicability not a consideration for glue choice. Instead the condition of the break is far more important to our glue choices.

When Rick Turner was active on the OLF he once posted about something that facinated me (yep I'm easilly facinated at times..). The idea was a head stock break that was not completely apart and still attached that could be clamped back into position for gluing. Rick talked about injecting very hot water into the joint, quickly adding HHG letting the wetness help wick glue further into the unbroken part of the failure and then clamping it all up quickly. This is where HHG shines or at least one place of many in that in addition to that micoscopic glue line it also can have it's viscosity altered as per the requirements of the application.

There is no one size fits all in most anything but HHG is close for Lutherie work but still at times other glues are more suitable depending on circumstances.

The HHG will have a strong initial tack which will help prevent slippage in the first place. High tack fish glue would also have those qualities while offering a much longer open time.

That jig is very cool. I've always just fussed with clamps and or in some cases pinned the pieces together.

Thanks for the advice everybody. Looks like I'm making a jig!

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Pat

The open time for HHG is not an issue if you preheat the parts before you glue.
the preheating also allows the glue to wick into very small places that will disappear when you clamp.

I do this for a living , and Dave Nichols taught me this ., My caul is simple a 1/2 piece of plexiglass for the top and the back of the head stock. If the break is clean I may use HHG or Tite bond. If there is a lot of cross grain breakage Epoxy , If the head stock veneer is damaged. I use that to work as a hinge to get things back into place. The more it is messed with the harder they can be to get a clean tight joint so be careful.
I get it together and clamp then tap and tighten . do this a few times and you should get it tight. Been using this for 10 yrs. Once you get it together is you need to replace the veneer you do that after you do the initial glue as you can then put in a spline under the veneer.

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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

John, are you saying that you put the cauls and clamps on, then as you increase clamp pressure and the thing starts sliding, you counter the slide by tapping on the top of the headstock? With your hand?

That's sort of what I was thinking. except just holding the headstock down with one hand and tighten with the other until the hide grabs. Sort of a "wild west" type of thing. Although if she slips, I'm gonna be wishin i would've made the slick Collins jig!


Do you always replace the vaneer?

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Pat