Salt in hide glue?

[polkat]

I've read a few things about putting urea in hide glue to extend working time, though I've never tried it.

But...I've also read that common table salt will give similar results. Anyone ever try this and did it work?

[fiddlecollector]

A few drops of lemon juice also is supposed to do the same.

Sorry scrub this comment i was tired and its `casting plaster`, not glue that lemon juice extends the working time.

[Bill Yacey]

It sounds like the first few ingredients for head cheese.

Is the salt or lemon juice supposed to extend the pot life of the glue, or lengthen the time before the glue sets? I thought the setting time is more dependent on ambient and wood surface temperature.

[polkat]

Extend the setting time, as I understand it. While I don't have the articles anymore, one pointed out that when gluing down a large piece (for example gluing on a top plate) it takes a little time to get the glue spread around to all surfaces, possibly enough time so that some of the glue is starting to set up before you can get the piece in place. Salt is supposed to extend the setup time so you can finish.

I have no idea if this actually works, hence the question.

[Homey]

Salt in portland cement will extend curing time. Also salt in beer is fun to watch.

[captainhook]

I've read a few things about putting urea in hide glue to extend working time, though I've never tried it.

But...I've also read that common table salt will give similar results. Anyone ever try this and did it work?

Yes and yes.

[Oded Kishony]

how does it affect the bonding strength and integrity of the glue joint?

Oded

[DBurns]

(for example gluing on a top plate) it takes a little time to get the glue spread around to all surfaces, possibly enough time so that some of the glue is starting to set up before you can get the piece in place. Salt is supposed to extend the setup time so you can finish.

[David Burgess]

According to Thordahl at Bjorn Industries, the addition of salt or urea will lower the resistance of the glue to moisture and high humidity. In other words, it will have a greater tendency to re-liquify, and perhaps to creep.

It's nothing I've ever wanted to mess with, particularly after seeing the various disasters from using "liquid hide glue".

[Bee Gee]

Salt in portland cement will extend curing time. Also salt in beer is fun to watch.

Homey Salt in a Wound will extend the time it hurts and may even increase the level of intensity? But while you are watching the salt in your beer would you test salt in Hide Glue in your Lab for me as this is my present area of needful information. My glue is setting before the ribs are fully lined up?

[Muswell]

According to Thordahl at Bjorn Industries, the addition of salt or urea will lower the resistance of the glue to moisture and high humidity. In other words, it will have a greater tendency to re-liquify, and perhaps to creep.

It's nothing I've ever wanted to mess with, particularly after seeing the various disasters from using "liquid hide glue".

Urea is used in intensive skin treatment creams because it absorbs and retains water. I used to get a lot of cracks and splits in my fingers, especially in winter. Since starting to use an urea based moisturiser the problem has gone. I am not knowledgeable about the science but I think I'll leave the moisturiser for my hands, not the glue.

[Muswell]

Do violin makers ever use go-bars? With everything to hand and the glue in a squeezee bottle you can get the back fully glued on a guitar and clamped in the time the violin maker was doing a short section.

[luthierwannabe]

I've read a few things about putting urea in hide glue to extend working time, though I've never tried it.

But...I've also read that common table salt will give similar results. Anyone ever try this and did it work?

Hi Polcat,

This article might be of some help to you. See post number 9. It is an email from Mr Eugene Thordahl of Bjorn Industries makers of hide glue to Mat Roop. It is a discussion on the use of salt and urea in hide glue. This is in public domain so I think it is OK to link to it.

http://www.violins.ca/forums/viewtopic.php?t=1441

Tony

[DBurns]

Old Brown Glue

"It has good initial tack, a 30-minute open time, and is reversible with heat and moisture – ideal properties for restoration, veneering, instrument making or assembling complex projects."

[baroquecello]

I would be affraid of what it could do on the long run. I know that in stone the salt can start crystalising and over centuries can tear up a statue, for instance. A few years ago an important statue (made in marble) on the grave of Willem van Oranje, the most important statesman in early history of the netherlands, had to be taken apart and cleaned of salt which had penetrated the marble and most likely originated from the mortar. Now, this statue was 400 years old, but I guess salt in the joint of top and back plates in time could do the same, and may not even need 400 years.

[Homey]

Thin with water and heat wood with heat gun or lamp probably the best bet. Or work faster

[Bernie R]

Do violin makers ever use go-bars? With everything to hand and the glue in a squeezee bottle you can get the back fully glued on a guitar and clamped in the time the violin maker was doing a short section.

Thanks for posting that Muswell. I have no idea if violin makers do anything like that, but it has certainly given me some ideas for my fiddle reassembly project. I read an article about Go-bars, and saw that at one luthier school they had shelving arranged so that go-bars could be inserted between the upper shelf and a guitar plate resting on the lower shelf.

[roundpond]

Peter Galbert chairmaker, who adds a small amount of urea fertiliser to his glue has found a new addition which might be of interest.

http://chairnotes.blogspot.com/2012/02/seeing-light-pt2.html - a flourescent reactor to detect where the glue goes.

Might help at the next stage.

[luthierwannabe]

Thin with water and heat wood with heat gun or lamp probably the best bet. Or work faster

Thinning with water to extend tack time...Not a good idea. See write up by Eugene Thordahl.

[David Burgess]

Thinning with water to extend tack time...Not a good idea. See write up by Eugene Thordahl.

It actually works quite well for gluing on tops and backs, where you don't want your ultimate bond strength anyway.

I've been using glue diluted to the point where it takes 3 minutes to start to gel for about 30 years now, and there haven't been any particular problems with seams opening. If you can't get all the clamps on in 3 minutes, the gel is flexible enough that the parts still clamp down pretty well, squeezing out the excess glue gel.

[Michael Richwine]

Our shop practice, especially with cellos and basses, is to put all the clamps on, get the ribs aligned, then undo three clamps at a time, work glue into the joint with a palette knife, clean and re-clamp, move on to the next three. You can stagger 1 clamp if you want to be sure of getting good overlap. It's worked for a lot of years on a lot of instruments.

[Melvin Goldsmith]

Our shop practice, especially with cellos and basses, is to put all the clamps on, get the ribs aligned, then undo three clamps at a time, work glue into the joint with a palette knife, clean and re-clamp, move on to the next three. You can stagger 1 clamp if you want to be sure of getting good overlap. It's worked for a lot of years on a lot of instruments.

I do something similar, normally in six hits of unclamping/reclamping on violin, viola or cello. I also use a diluted glue similar to David's in post 20.

[Bee Gee]

Thin with water and heat wood with heat gun or lamp probably the best bet. Or work faster

Thank you Master I shall heed your advise, Perhaps you would reflect "when have I ever worked faster"?

Bobarius