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On another post several of you provided advice on the mixing of hot hide glue. I followed that successfully and made up a batch. The consistency seemed appropriate and I also watched a video someone suggested. After making the glue and heating to 140 degrees and letting it all turn to liquid I let it set overnight and then brought it to 140 degrees before attepting to use. My mistake - did not practice before attempting to use and it seemed very thin compared to the tight bond I usuall use. Was glueing a soundboard to the rims. Got worried immediatelly and switched to tight bond, my familiar approach. Now I was applying with a squeeze dispenser similar to tight bond.

My questions:

1. Is hide glue normally a thinner consistency than tight bond?
2. Should I apply thinly with a brush instead of squeezing on?

It did stick well in the small area I applied before aborting but it was messy.

Thanks. I know this is pretty basic and no brainer for most but new to me. I will be practicing on scrap before using again shortly.

HHG does not have the sane consistency as Titebond, it run a little more. You can put more solid glue in your mix until you are comfortable with the consistency. The thicker it is, the quicker it will gell.

Rich...The consistency you describe is appropriate for gluing braces. When applying to the rims, I make it a bit thicker so a bead stays balanced on the kerfed liner. Heat all the surfaces before hand, keep the room warm, apply it quickly and get the plate clamped down within a minute. If this sounds scary then practice on dry runs until you feel confident. You may want someone to help with clamping until you feel you can do it yourself.

Or you can always use Fish Glue for the plates...you'll have plenty of open time! I changed to FG 2 years ago for the plates and love it.

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JJ
Napa, CA
http://www.DonohueGuitars.com

The thing I would add is, if you're using very thin HHG, you may want to brush some on your pieces a few times until the wood doesn't absorb the moisture anymore, especially with spruce, WRC etc. It's easy to starve a joint with thin HHG, and it's also harder to clean up, but it has its use.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

I've also switched to fish glue for bracing and plates. Still use HGG for my neck to body dovetail joints for no reason other than I like the process. Fish glue would work just as well.

1) Yes - Liquid honey at 140 F will be very close to the consistency of hot HGG.
2) Either way as long as you get some squeeze out. The trick is not to starve the joint, so watch the amount much pressure you apply.

If you decide to try Fish glue you’ll see it very close to working with many of the white/yellow carpenter glues available today, just easier to clear-up.

_________________
Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

Thank you all for the advise. I will be doing some practicing. One question - from your post it sounds like I can brush on a base and let it dry and then apply over the top of the base glue. No need top sand or scrape off. Is this correct.

Also, I keep seeing more and more using Fish Glue. I checked out Stew Mac and didnt see it. What would be a good source for purchase.

Thanks again all. Always appreciate the help.

You could, the new hot glue will re-activate the old one.
But what I meant is, if you're using thin HHG, keep brushing (with new HHG) until the wood doesn't soak it anymore, 2 or 3 applications are usually enough. You'll have enough glue to not starve the joint, an you're keeping it hot.
I do not use fish glue, but Lee Valley has it.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

JJ,
Where do you buy your fish glue? I'm going to give it a try gluing the plates on the rims.

Hutch

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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

Norland makes good fish glue and I believe Lee Valley sells it. I've been using it quite a bit in the last year pretty much anytime I would have used titebond and when I need the open time.

_________________
Steve Smith
"Music is what feelings sound like"

You can buy it directly from Norland, but you have to buy by the gallon. Lee Valley re-packages it into quarts, and some small bottles with a brush in it.

_________________
Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

The objective with HHG, or any other, really, is to end up with a nice uniform thickness of DRIED film, between .002"-.006" between the parts in the end. That yeilds the strongest joint, all else equal. With HHG there's the additional constraint that you need to get all of the clamps on before it gels. This gets to be a pretty complicated equation, balancing the viscosity of the glue mix, the gram strength of the glue, the fit of the parts, clamping pressure, and temperature of the parts.

Mixing the glue a bit thinner gives you a longer working time, all else equal, and reuires that you use less clamping pressure to avoid starved joints. The lower pressure means that you can't use the clamps to pull things in: they have to fit correctly to begin with. I think one reason cabinet makers mix the glue a little thicker is that they often do need to pull the heavier pieces in with clamps, so the glue needs to have more body to resist that.

Too much warming of parts can cause problems. For one thing, it can cause the glue to dry as you are spreading it. More usually, though, it makes it too liquid, and you end up with a starved joint using only moderate clamping pressure.

Higher gram strength glue has a shorter working time . I'm not sure we need it anyway. I use the 192 gram glue that Woodcraft sells, and get 100% wood shear on test joints, so what the heck.

I use rubbed joints when assembling plates for arch top instruments. Spread the HHG on the freshly planed surfaces, rub them togehter until it starts to grab, make sure they're lined up right, and walk away for at least a couple of hours. The glue itself takes care of any 'clamping'. The only failures I've had were from over heating the joint, and once when some hairs from Carleen Hutchins' glue brush ended up in the joint. HHG is actually pretty forgiving, but there are things it won't put up with.