Hot Hide Glue

[Sean Rainaldi]

Anyone have a good source for hot hide glue?

Also any info or source on how to prepare it, use it, gram strength suggestions for specific applications, etc would be appreciated.

[Rod Sheridan]

Well Sean, it's not actually hot, you have to heat it yourself...LOL

Lee Valley sell it, so you could drop by a store, or have it mailed to you. They also have instructions on how to use it.

A glue pot is required to keep the glue at the proper temperature........Regards, Rod.

[Sean Rainaldi]

You mean Lee Valley does not ship it already in the glue pot all warmed up and ready to use? Gee what kind of cust service is that...

[Rod Sheridan]

You mean Lee Valley does not ship it already in the glue pot all warmed up and ready to use? Gee what kind of cust service is that...


I guess our famed Canadian customer service isn't what it used to be......Rod

[Loren Hedahl]

Hot hide glue is used in the wooden musical instrument trade mostly, pianos, violins, guitars and other stringed instruments.

The two major reasons for its use is tact-ability and reversibility.

When you mix it with water in the correct proportion and at an elevated temperature, it becomes a liquid about the viscosity of honey. When it is cooled to near room temperature it turns into a gel. For musical instrument technicians the advantage over most other glues is that once glue is applied to a small part, the part can be placed on the assembly, held in place for a moment until the glue gels and it will stay there. It won't have complete adhesion, but enough so assembly can continue.

The second advantage over most other glues is that the part can be loosened and removed, i.e., reversibility. This is done by heating, steaming and/or soaking. This might seem a bit unwieldy, but it is quite easily done.

Piano technician supply houses are a great source. There are many options for heating it also. A special purpose pot is nice, but all you need is something that will give a stable heat in the 130 - 140 degree range -- think an inexpensive RIVAL electric water pot with a glue container inside.

With the internet resources available, I'm sure you can quite quickly gather more information on the subject than you would need in several lifetimes. Good luck.

[Carlos Alden]

Sean:

Here's a great link about using hide glue:

http://www.frets.com/FretsPages/Luthier/Data/Materials/hideglue.html

It's directed at musical instrument makers and techs, but it really covers a lot of information.

You can get hide glue at Lee Valley, Garrett Wade, or any musical instrument supply place like Stewart MacDonald (http://www.stewmac.com) or Luthier's Mercantile (http://www.lmii.com/)

Carlos

[Sean Rainaldi]

Thanks so much for all the information guys appreciate it.

Anyone who uses it, do you have a favorite brand of glue pot that you like? I'll be using it in the garage, so I won't have easy access to the stovetop in the kitchen.

[David Keller NC]

Sean - I use hot hide glue almost exclusively in building furniture ( antique reproductions, mostly). I buy mine from www.thebestthings.com (http://www.thebestthings.com). Hide glue comes in a number of different strengths - it's referred to as the "gram strength" and I've been informed by those in the know on FWW's Knots forum that it's measured by the weight the gelled glue will support. The higher the gram strength, the higher the collagen and other extractables from the bones and hide that the glue contains. Typically, I see the 192 gram strength recommended for cabinetmaking, because it's a good balance between workability and the ultimate strength of the dried glue. To my knowledge, most of the woodworking dealers that sell it (Lee Valley, The Best Things, Tools for Working Wood, etc...) sell this strength.

About preparation - you want to put the dried glue in the container in which you want to prepare it in (I use a glass mason jar), add about the same volume of water, and let it swell for 30 minutes. It should form a goopy mass. Put that goopy mass in a hot water batch (no more than 140 degree F - boiling will rende the glue unusable. YOu want th consisitency to by of "runny honey" of hot maple suryp. When you pull the brush out, it should drool off the end in one continuous stream rather than break up into droplets. If it's too weak, add more (distilled) water, if it's too strong, add a little more dried hide glue.

The liquid will keep for a couple of days if kept at the right temperature, an longer if you put it in a closed container in the refrigerator.

[Sean Rainaldi]

Sean - I use hot hide glue almost exclusively in building furniture ( antique reproductions, mostly). I buy mine from www.thebestthings.com (http://www.thebestthings.com). Hide glue comes in a number of different strengths - it's referred to as the "gram strength" and I've been informed by those in the know on FWW's Knots forum that it's measured by the weight the gelled glue will support. The higher the gram strength, the higher the collagen and other extractables from the bones and hide that the glue contains. Typically, I see the 192 gram strength recommended for cabinetmaking, because it's a good balance between workability and the ultimate strength of the dried glue. To my knowledge, most of the woodworking dealers that sell it (Lee Valley, The Best Things, Tools for Working Wood, etc...) sell this strength.

About preparation - you want to put the dried glue in the container in which you want to prepare it in (I use a glass mason jar), add about the same volume of water, and let it swell for 30 minutes. It should form a goopy mass. Put that goopy mass in a hot water batch (no more than 140 degree F - boiling will rende the glue unusable. YOu want th consisitency to by of "runny honey" of hot maple suryp. When you pull the brush out, it should drool off the end in one continuous stream rather than break up into droplets. If it's too weak, add more (distilled) water, if it's too strong, add a little more dried hide glue.

The liquid will keep for a couple of days if kept at the right temperature, an longer if you put it in a closed container in the refrigerator.

Thanks so much David,

The hide glue that lee valley sells is rated at 260g± Bloom strength (whatever that means). Their site claims it is a "very strong one".

For my application, I am gluing up end grain boards about 7/8 inch thick, they will not be exposed to water or high heat. I need the glue to withstand repeated extreme pressures. Think this glue is good for high pressure?

BTW, I just saw the Hold-Heet Glue Pot (Made in USA) @ http://www.thebestthings.com/newtools/hide_glue.htm (http://www.thebestthings.com/newtools/hide_glue.htm)
Think this is a good one?

[John Downey]

Tools for working wood also carries hide glue, I've been meaning to order some as I'm almost out. Since most of my projects are small, I use a tinned 1 1/2" copper pipe cap as a glue pot, heated with one of those individual coffee cup warmers I got at Walgreens or somewhere like that for $10. A small glue pot keeps you from mixing too much and having it start to mold before you can use it up.

[Mike Henderson]

Hot hide glue has certain advantages, which Loren covered well. It also has some disadvantages which you need to think about. It takes time to get the glue ready (to get it heated up). The glue has a limited lifetime - it spoils after a while. Most woodworkers have switched to more modern glues because of the disadvantages of hide glue.

There are many modern glues which have various properties, and one of them may fit your needs - and not have the disadvantages that hide glue has.

Mike

[Sean Rainaldi]

Hot hide glue has certain advantages, which Loren covered well. It also has some disadvantages which you need to think about. It takes time to get the glue ready (to get it heated up). The glue has a limited lifetime - it spoils after a while. Most woodworkers have switched to more modern glues because of the disadvantages of hide glue.

There are many modern glues which have various properties, and one of them may fit your needs - and not have the disadvantages that hide glue has.

Mike

By limited lifetime, do you mean while in the glue pot before use? Or after it has been applied to wood?

[Mike Henderson]

By limited lifetime, do you mean while in the glue pot before use? Or after it has been applied to wood?
No, in the glue pot. We have furniture from the 18th Century that was put together with hide glue and it's still doing fine.

Mike

[Frank Drew]

We used hot glue exclusively in the 18th century reproductions shop where I apprenticed; I liked it, but when I opened my own shop I chose to use white or yellow glue for the most part although I did keep some hide glue on hand that I'd use from time to time, melted in a simple double boiler on a hot plate. It's nice for rub joints although yellow glue works almost as well.

To me the great disadvantage of hot glue is that you have to work very fast before your glue gels -- the open assembly time is measured in seconds. Makes complicated glue ups highly stressful, to say the least. IMO, it's absolutely out of the question for bent laminations, for instance. Veneering with it is tricky unless you can heat a sheet of metal, like zinc, to remelt the glue you've brushed on your substrate.

Others might differ.

[Jack Briggs]

Bjorn Industries: http://www.bjorn.net (http://www.bjorn.net/)

They sell bulk only - I think 5 lbs. minimum order.

[Arnold E Schnitzer]

One advantage hide glue has over PVA-type glues is that it does not creep. It cures absolutely rigid, and glue joints become virtually invisible and stay that way. I use 192 gs from Bjorn industries in my instrument-making, toss it after 3 days or so, and keep it in a glass jar with a lid so it does not thicken up. At night it goes in the fridge. I add about 10% urea granules which extends the open time to about a minute or so. It's very important to rehearse glue-ups so that the parts can be put together under pressure immediately. Working with hot hide glue in a cold space is not an option, though warming parts prior to glue-up helps. If the glue begins to gel before the pressure is applied, it will not adhere. I hope this is helpful.

[Sean Rainaldi]

I've heard that despite the hassle with learning how to correctly prepare it for your application, that Hide Glue is the strongest glue available for woodworking. Is this accurate?

[Mike Henderson]

I've heard that despite the hassle with learning how to correctly prepare it for your application, that Hide Glue is the strongest glue available for woodworking. Is this accurate?
No, I don't believe that's true although I can't point to some tests right now. Modern glues are very, very good.

Additionally, almost any woodworking glue is stronger than the wood. Your choice of glues should probably be based on other properties of the glue, rather than strength (since essentially all are more than strong enough).

Mike

[Frank Drew]

What Mike said.

[Loren Hedahl]

Bjorn Industries: http://www.bjorn.net (http://www.bjorn.net/)

They sell bulk only - I think 5 lbs. minimum order.


That's cool. Then you only have to buy it once! :>)

[Sean Rainaldi]

This is why I asked about the strength comparison - this guy swears that hot hide glue is much stronger than PVA glues (he restores player pianos):

http://www.player-care.com/hide_q-a.html

To add later -

Also here's something else interesting I just found:

http://www.inthewoodshop.org/2005/hideglue.shtml

BUT, then I read this test published in Fine Woodworking Magazine comparing hide glue and PVA glue; they claim PVA is stronger but I believe the test results are skewed in favor of PVA's and I'll tell you why: http://www.titebond.com/Download/pdf/HowStrongisYourGlue_FWW.pdf

I'm curious if that test data was generated by someone somehow involved with the manufacturers and or advertising of PVA glue, considering the above two web sites of artisans who swear by hide glue.

I’m not trying to berate the fine woodworking article here, the reason why I bring this up, is I find it interesting that the testing in Fine Woodworking did not list the actual gram strength of the hide glue. Since there are many different gram strengths of hide glue which vary vastly in strength for different applications, and the same is not true for the PVA glues that they tested (I don’t believe there are different gram strength of PVA glues offered as a product to woodworkers please correct me if I am wrong), they could have easily tested PVA glues against a low gram strength of hide glue, instead of a high gram strength of hide glue, to make their test results look better in favor of PVA glue.

So if they are not going to scientifically conduct this study with the relevant product data of the gram strength of the hide glue they are using to compare to PVA's, it calls into question the test results and the validity of the testing and objectiveness of the test itself.

For example (this is just one comparison I have not checked out all brands of hide glue yet), Lee Valley sells two different strengths of hide glue. They sell a pearl hide glue which is rated at 150g Bloom strength, and they also sell a granular type rated at 260g± Bloom strength. Lee valley claims this glue is a "very strong one. I have not checked but I’m sure there are many other different grades and gram strengths and types of hide glue out there from what I am learning.

So in this above test in Fine Woodworking Magazine, what gram strength are they using? 150g? 260G? Something in between? 50 gram?

Who knows…

From what I have read about Bloom Strength (someone correct me if I am wrong), I understand that this test determines the weight (in grams) needed by a probe (normally with a diameter of 0.5 inch) to deflect the surface of any gel (in this case hide glue just removed out of the glue pot before application) 4 mm without breaking it. The result is expressed in Bloom (grades). It is usually between 30 and 300 Bloom.

If I am correct here, this would imply that hide glues vary widely in their gram bloom strength and the above test is not even discussing this aspect of hide glues

The test report brochure looks all very impressive and scientific, but when you look at the actual data, it surprises me because the testing was supposedly done at Case Western Reserve University in Cleveland, and for them to omit such important data of gram strength of hide glue they are testing against PVA, seems like their scientists really missed the boat on this one.

I would also like to know how much advertising money fine woodworking gets for PVA glues compared to hide glues - because that is a legitimate question if they are going to publish scientific test results conducted by universities which supposedly are objective. Hey, it's a legitimate question.

I'd like to see some independent and objective test data which compares PVA and hide glues, with the actual gram strength of the hide glue(s) they are comparing to the PVA's.

[Wayne Cannon]

Here are some links I found very useful when I decided to try hot hide glue a few months back -- including a cheap thermostatically-controlled hot hide glue pot that works very well:


Hide Glue 101: http://www.nawcc-mb.com/bbv2/bbBoard.cgi?a=viewthread;fid=14;gtid=151109;gpid=1 51109#gpid151109
Make the world's best hot hide glue pot for under $20: http://www.spurlocktools.com/id57.htm
A simple hot hide glue setup: http://www.norsewoodsmith.com/node/106
Bjorn Industries: http://www.bjorn.net/
Milligan & Higgins: http://www.milligan1868.com/

[Mike Henderson]

The subject of hide glue is a bit like religion - some people become "true believers" and find lots of reasons to justify their beliefs. So my advice is to look for unbiased studies before you drink the Kool-aid - not just studies that say what you want them to say.

In any case, strength should not be the major factor in your glue choice since most glues are stronger than the wood.

Mike

[Dan O'Sullivan]

To me the great disadvantage of hot glue is that you have to work very fast before your glue gels -- the open assembly time is measured in seconds. Makes complicated glue ups highly stressful, to say the least. IMO, it's absolutely out of the question for bent laminations, for instance. Veneering with it is tricky unless you can heat a sheet of metal, like zinc, to remelt the glue you've brushed on your substrate. Earlier post.

Frank it might be good to try some urea in the hide mix if set up time is frustrating. I don't use the 250 stuff much at all -- way too fast set up. It might be great for rub joints but the 190 is good for that in all of the times I have used it. Putting a little urea in the hot mix will slow the dry/set up time down significantly. I use it quite often when I need some time. Makes a big difference.

Convenience: I use Patrick Edwards Olde Brown Glue right out of the bottle. The stuff is great. Lasts about 6-9months. Its a bit more than using yellow glue but the advantages and convenience for me is worth the added cost. This is good stuff.

Building chairs(windsors and some contemporary stuff) is a field I strongly encourage the use of hide glue(hot or cold). The ability to reactivate the glue is important.

Hide glue has a learning curve but I would encourage others to experiment with it and use it for the unique benefits.

Dan