Hot Hide Glue Question

[Mike Henderson]

When I do a project such as a chest of drawers, I usually use half blind dovetails to attach the bottom to the sides. I'm attempting to learn more about hot hide glue and want to do a project using it. Note the word "hot" for the hide glue. I'm not looking to use liquid hide glue, I want to use hot hide glue like our ancestors did.

When you apply glue to half blind dovetails, it takes a long time. I apply glue to the insides of the sockets and to the sides of the tails - on both sides. The tap the bottom on to the sides, and clamp up and down, and across the bottom to pull everything tight. And, of course, the top has to be addressed in this glue up, also, which takes more time applying glue.

How do you do such a glue up with hot hide glue? The glue will cool by the time I get it applied to all the parts. I could apply the glue, let it cool, then come back with a heat gun and warm up each joint before tapping the joint together. But two issues:

1. After I warm up the joint, I can tap the tails into the sockets and they'll be held there as soon as the glue cools. But I like to clamp across the bottom to pull the sides in tight to the bottom so that the dovetails look "tight". While this doesn't matter much on the bottom of a chest, it will matter for visible dovetails so I want to figure out how to solve this problem.

2. Our ancestors didn't have heat guns. How did they address this issue?

Your advice and suggestions will be appreciated.

Mike

[paul cottingham]

Honstly, a little urea in the glue increases open time. For most projects that require open time, i use Old Brown Glue. It has the urea in it, and my hands are so buggered, i need the extra open time.

[Dave Anderson NH]

For dovetails I only apply the glue quickly and heavily to the sockets since most of the strength of any dovetail is mechanical. I also make sure the parts to be joined are quite warm. I place them by my woodstove much as our ancestors did, but you could use an electric blanket as some of my friends with cold shops do. Equally important Mike is having everything organized, arranged for quick access, and ready to go before the brush leaves the glue pot.

Edit: I still keep an old hair dryer handy just in case.

[jamie shard]

I remember seeing >somewhere?< a old film of a cabinet maker dipping in a drawer side and front into a big pot of hot hide glue and then slapping the pieces together. So that's one approach. I suppose after it gels, the extra could be scraped off and put back in the double boiler.

[Warren Mickley]

Your big mistake is doing all four corners at once. Instead put the bottom on the bench (or the floor) in front of you. Then put glue on one side and put it together. Then put glue on the other side and put it together. You now have the bottom on the bench with the two sides straight up. Apply glue to the remaining two joints and put together. So you are doing the gluing in three stages, none of which should take a whole minute.

I have seen some guys who insist that they need 30 minutes or even more "open time" for some "complex glue up". We don't work that way with hide glue.

[Mike Henderson]

I remember seeing >somewhere?< a old film of a cabinet maker dipping in a drawer side and front into a big pot of hot hide glue and then slapping the pieces together. So that's one approach. I suppose after it gels, the extra could be scraped off and put back in the double boiler.

You bring up a good point. I forget that with hide glue it's not critical to keep the glue off of the non-joint surfaces. I need to change my thinking when working with hot hide glue.


Your big mistake is doing all four corners at once. Instead put the bottom on the bench (or the floor) in front of you. Then put glue on one side and put it together. Then put glue on the other side and put it together. You now have the bottom on the bench with the two sides straight up. Apply glue to the remaining two joints and put together. So you are doing the gluing in three stages, none of which should take a whole minute.

I have seen some guys who insist that they need 30 minutes or even more "open time" for some "complex glue up". We don't work that way with hide glue.

I understand. But I don't think I can put glue on all of the dovetail surfaces and get the joint together in a minute. I'll have to practice.

Mike

[Robert LaPlaca]

Mike, I don't have any silver bullets here, but a bit of urea or salt (5 -10% by weight) will slow down the gelling and get you like 3 or 4 minutes of open, the other suggestion of glueing in stages is also another good technique.. And lastly, get yourself some of those contractor halogen work lights at a big box store, on high they produce enough radiant heat to slow down the gelling and keeps the parts warm..

Or use Olde Brown glue..

[paul cottingham]

Seriously. Old Brown Glue. Lots of open time. Heat it like your home made stuff.

[Mike Henderson]

Seriously. Old Brown Glue. Lots of open time. Heat it like your home made stuff.
Thanks for your suggestions, Paul and Robert. But, for reasons of my own, I want to learn how to work with traditional Hot Hide Glue (HHG).

My goal is not to just be able to glue furniture together but to understand how our ancestors worked. And to do that, I need to work with the kind of glue they used. I know they could have used urea and/or salt but I want to start with standard hide glue.

Already, I can see that working with it requires thinking about the glue and the glue-up process differently.

Mike

[And thanks, Robert, for the idea about the work lamps. I have some of them.]

[ken hatch]

Thanks for your suggestions, Paul and Robert. But, for reasons of my own, I want to learn how to work with traditional Hot Hide Glue (HHG).

My goal is not to just be able to glue furniture together but to understand how our ancestors worked. And to do that, I need to work with the kind of glue they used. I know they could have used urea and/or salt but I want to start with standard hide glue.

Already, I can see that working with it requires thinking about the glue and the glue-up process differently.

Mike

[And thanks, Robert, for the idea about the work lamps. I have some of them.]

Different gram strength hide glue have different open times. Check out TFWW's web page on hide glue.

ken

[Mike Henderson]

Different gram strength hide glue have different open times. Check out TFWW's web page on hide glue.

ken

Yes, I have read their page - and everything else I can find on the Internet. Also ordered a book (http://www.amazon.com/gp/product/B0034WT9W6?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00)on hide glue. I'm starting with 192 gram strength.

Mike

[ken hatch]

Yes, I have read their page - and everything else I can find on the Internet. Also ordered a book (http://www.amazon.com/gp/product/B0034WT9W6?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00)on hide glue. I'm starting with 192 gram strength.

Mike

Mike,

I use 251 for most applications but I also glue up like Warren suggested. Because 251 gram strength will make good "rub" joints and I draw bore when able i will use very few clamps during the glue up, usually only to pull a case square if needed.

ken

P.S. Good on you for trying to figure out how the "old guys" did it. I find it will usually be the best way.

P.P.S. I also find working that way takes all the pressure off, glue or draw bore a joint, have a cup of tea, do the next joint, repeat until there are no more joints.

[Keith Mathewson]

I use hot hide glue with increasing regularity and I now use it thinner than when I first started. Thicker glue gels too fast and doesn't improve the strength. On dovetails I apply glue as Warren suggests but the biggest factor in open time is temp. All that said when I visit museums I notice that the dovetails on the old classics would be considered pretty bad by todays standards. Of the three pics shown two are from a piece in the Met Museum, the front anyone would be proud of but it dovetails aren't so pretty and it's not because they lacked talent.

[jamie shard]

Mike, another approach for hot hide glue and dovetails is "the wedged dovetail". http://www.popularwoodworking.com/woodworking-blogs/chris-schwarz-blog/on-gaps-and-dovetails-and-winterthur In particular look down in the comments. Hope this helps!

[Zach Dillinger]

I use hot hide glue with increasing regularity and I now use it thinner than when I first started. Thicker glue gels too fast and doesn't improve the strength. On dovetails I apply glue as Warren suggests but the biggest factor in open time is temp. All that said when I visit museums I notice that the dovetails on the old classics would be considered pretty bad by todays standards. Of the three pics shown two are from a piece in the Met Museum, the front anyone would be proud of but it dovetails aren't so pretty and it's not because they lacked talent.

Those are beautiful. After all, the piece is still here...

[Christopher Charles]

Hello Mike,

Good on you for going way old school. Check the old drawings and sources for the amount of clamps and clamping. Will likely support Warren's suggested approach.

Best,
C

[Jeff Ranck]

Rather than glue and warm up the joint, use your heat gun (or the wood burning stove like someone else here said) to warm the wood before you start. I remember watching a video of someone assembling a very complicated joint in a chair and that is what they did. Use a heat gun to warm up the wood joints really well, then if you have a radiant heat source or whatever, it can help keep the wood warm while you work.

I don't have a wood burning stove, so I've taken to using my heat gun to warm the wood before I start. It has helped a lot with open time. I also have the luxury of having a well heated shop so this time of year that helps too

Jeff.

[Bob Glenn]

I think most of us have been taught or become accustomed to trying to be cautious when applying glue to joints, due to cleaning up the mess and squeeze out. I have seen an old film showing a worker dipping a tenon in the glue pot before assembly. Also, they often used a glue spoon rather than a brush to dispense the glue on the mating joints quicker.

[Steve Voigt]

…for reasons of my own, I want to learn how to work with traditional Hot Hide Glue (HHG).

My goal is not to just be able to glue furniture together but to understand how our ancestors worked. And to do that, I need to work with the kind of glue they used. I know they could have used urea and/or salt but I want to start with standard hide glue.

Already, I can see that working with it requires thinking about the glue and the glue-up process differently.



Good for you. Have you tried looking at old texts, e.g. Robert Wearing, Charles Hayward, David Denning, for any tips?
Some good pointers here already about using salt/urea, doing one joint at a time, and heating the work. One other: have you tried starting the joint before applying glue? Christian Becksvoort discusses that here (https://www.startwoodworking.com/sites/default/files/chris-becksvoort-favorite-dovetail-tricks.pdf), but you would presumably want to modify his approach by doing just one joint at a time.

[Scott DelPorte]

If you are looking for "old school", I read that Antonio Torres, who is a very well known early guitar maker, faced a similar problem with gluing the wooden bindings on his guitars with hide glue. Not suggesting you try this, but the book said he used a mop to apply alcohol to the assembled and clamped glue joints, then lit them on fire to re-liquify the glue so it would bond properly.

[Mike Henderson]

I tried putting a glass jar in water inside the "Hold Heet" pot, with the hide glue in the glass jar. The Hold Heet gets the water to the correct temperature fairly quickly (140 to 150 degrees F) but the glue in the jar never gets to that temperature. It mostly stays at 120 or below. I let the jar sit in the water for close to an hour - with it covered - and it still never got to temperature.

I was able to glue up some wood as a test by heating the wood with a heat gun. After letting the wood sit in clamps for several hours, I sliced off pieces of wood across the glue line, and broke them to see if the glue was stronger than the wood. Mostly, it broke the wood, but a part of the fracture was along the glue line.

I'm going to have to make the glue directly in the pot so it gets to the right temperature. I'll keep testing and post occasionally on my progress.

Mike

[Keith Mathewson]

Something is wrong. I have two of those and keep the glue in glass salsa jars. When I heat the glue I don't leave the lid on and I leave it for about a hour while I get ready. I test the temp with a insta-read thermometer and it reads about 140f.

[Craig Regan]

On complicated glue ups, brush a a very thin sealer coat of glue on both pieces of wood and let it cure. Make sure the glue is thin enough to soak into the wood fibers and not clump up on the surface. When its time to glue up the parts, have the joints started, then brush on a thin solution of hot glue and clamp. The new hot glue will reactivate the older sealer coat and create a nice bond. Keep your glue thin - the thinner the glue, the more open time you will have, Also, only do glue ups in very warm rooms (75 - 80) and make sure the parts are warm. I usually keep two solutions of glue in the shop; one watery thin for seal coats and one full strength for glue ups. Even the "full strength" is on the thin side. I usually gauge viscosity with my finger to check for tackiness and how fast it coagulates.

[Warren Mickley]

A few notes. The 140 degrees is not a magic number. We were using hide glue long before Daniel Fahrenheit was born. The reason the Hold Heet uses this temperature is that some shops keep the pot hot all the time. At 140 degrees the glue will last for about a week. Hotter temperatures work fine for gluing, but the glue degrades more quickly sitting in the warm pot. And the glue is gradually cooling as soon as we load up the brush; it also works at somewhat lower temperatures.

We usually make a wooden lid for the pot. When it warps from the moist heat we turn it the other way, back and forth a few times until it is stable. A lid ought to keep your jar warmer.

[george wilson]

If you put urea in your hide glue,you have turned the glue into regular bottled liquid hide glue like you can buy in the hardware store.

That said,liquid hide glue was shown to be stronger than original hide glue in a Fine Woodworking test years ago. Liquid hide glue is not as brittle as pure hide glue.

That said,I prefer to use real hide glue on guitars as it is more "transparent" to sound vibrations. I also think it will not allow creeping of joints since it is not at all elastic.

[Mike Holbrook]

Peter Galbert believes in making chair joints that do not need glue but he uses "hot" hide glue in his chair classes, understanding that we don't all make perfect joints. He keeps a bottle in warm water all day with everyone in the class using it for gluing all the pieces in their chairs. Peter talks about why he uses liquid & hot hide glue in pgs 21-23 in his new book. He says he uses hide glue because "it is the only glue that is both cohesive and adhesive, meaning it will stick to other things and, more importantly to itself." The value added being the ability to repair loose joints simply by applying a little heat, moisture and fresh glue.

If you check Amazon for the little electric wax heaters that nail salons use you can pick something up much cheaper than the expensive hot glue pots that woodworking stores tend to sell. I just bought one for around $20. Baby bottle warmers are also popular for keeping the glue warm. I don't think the exact temperature is critical., as Warren mentions. I am pretty confident I was using glue that was just relatively warm.

I thought Mike H made a post on my post about hot hide glue suggesting the nail salon wax heaters recently?

[Tony Corey]

Mike,

I too plan on experimenting with and using hot hide glue. I'm not there yet but like you I have done lots of reading on the subject. Warming the parts before gluing was done in the "old days".

In fact I seem to remember reading that some shops had a glue up room in the center of the shop which would be kept warmer the rest of the shop, especially in the winter...think wood/coal stove. The pieces to be assembled would be moved to the glue room to get warm before the actual assembly was done. So, like Craig and Jeff suggested, get the parts warmed up by whatever means you have available.

For the life of me, I cannot find the article so I can provide a link.

TonyC

[Mike Henderson]

That seems to be one of the major weaknesses of hot hide glue - that it's a hot process, meaning that you have to keep everything fairly warm while gluing. I can understand why people jumped on modern glues when they became available. No waiting for the glue to get hot, and no worry about the joint getting chilled before you get it together - much longer open time.

I'm getting ready to try some hammer veneering. I'll have to see how that goes.

Mike

[Keith Mathewson]

Mike,

Here is a link to a youtube that I quite enjoy https://www.youtube.com/watch?v=awIBy11kMA8

I learned to veneer from this persons videos.

[David farmer]

If you open up your Hold heat pot, I think you will find a screw to adjust the temperature.
Make sure your thermometer is correct.
192 gram strength is plenty strong.
I use a pair of 250 watt heat lamps aimed down on my work (guitars) to keep parts and glue warm as I'm applying glue and assembling.

[Roy Lindberry]

When I do a project such as a chest of drawers, I usually use half blind dovetails to attach the bottom to the sides. I'm attempting to learn more about hot hide glue and want to do a project using it. Note the word "hot" for the hide glue. I'm not looking to use liquid hide glue, I want to use hot hide glue like our ancestors did.

When you apply glue to half blind dovetails, it takes a long time. I apply glue to the insides of the sockets and to the sides of the tails - on both sides. The tap the bottom on to the sides, and clamp up and down, and across the bottom to pull everything tight. And, of course, the top has to be addressed in this glue up, also, which takes more time applying glue.

How do you do such a glue up with hot hide glue? The glue will cool by the time I get it applied to all the parts. I could apply the glue, let it cool, then come back with a heat gun and warm up each joint before tapping the joint together. But two issues:

1. After I warm up the joint, I can tap the tails into the sockets and they'll be held there as soon as the glue cools. But I like to clamp across the bottom to pull the sides in tight to the bottom so that the dovetails look "tight". While this doesn't matter much on the bottom of a chest, it will matter for visible dovetails so I want to figure out how to solve this problem.

2. Our ancestors didn't have heat guns. How did they address this issue?

Your advice and suggestions will be appreciated.

Mike

Mike,

I'm in the same boat as you. I like using hot hide, but I need to get quicker at gluing up. You've heard the suggestion to add salt or urea, but remember that as you increase open time by this method, you will compromise the gram strength of the glue. If that's not important, then this might be the avenue for you.

As far as how our ancestors did it, they had an apprentice or two in the shop. I recall seeing a video of George Wilson at Williamsburg (https://www.youtube.com/watch?v=K48FezBoPWg) building a harpsichord and violin. Whenever it was time to glue up, all three guys gathered around the glue pot with a brush in hand. This allowed for a much more rapid application of glue as well as many hands to hold the piece(s) in place, reducing the need for clamps.

[Mike Henderson]

Mike,

Here is a link to a youtube that I quite enjoy https://www.youtube.com/watch?v=awIBy11kMA8

I learned to veneer from this persons videos.
I looked at the video but what he does is pretty basic. What I need is more information about veneering a complex veneer panel with hot hide glue. For a simple example, a four way match of veneer, with banding and a border.

When doing a four way match you have to very carefully cut and match the four pieces so they have to be cut and matched before you begin the gluing process. When doing this with regular glue, I'd cut the veneer, tape it together with veneer tape, then put it in press with glue on the substrate.

The thing I'm concerned about is that the veneer tape releases with water and hide glue is water based. If the veneer tape gets wet it's likely to let go.

So how do you hammer glue a "fancy face" veneer? Do you put it down on the hide glue and it sticks enough that if the veneer tape comes loose the individual pieces of veneer don't' shift when you use your veneer hammer? How did our ancestors do things like a radial match with hot hide glue?

Suggestions or instructions will be appreciated.

Mike

[Veneering a radial match with a veneer that was rotary cut would seem to be impossible with hot hide glue (example of rotary cut veneer - waterfall bubinga, also known as kewazinga bubinga). When doing a radial match of waterfall bubinga with modern glues, I have to use a non-water based glue. Otherwise, you wind up with a potato chip as soon as it absorbs moisture.]

[Jeffrey Martel]

You wouldn't hammer veneer anything that needs to match up like marquetry, 4 way match, etc.

What I've seen done is to do it as quickly as possible, and then use heated cauls in a veneer press. That is, get some 1/4" aluminum to use on the cauls on bottom and top of the veneered panel, then your normal wood cauls. Heat them up so they are fairly warm to the touch with a propane torch/grill/etc. If it's too hot to hold, it's too hot for the veneer. This will reactivate the hide glue while you clamp it down in a screw press. Plus it lengthens the time that the glue cools, so you can readjust if needed. Also useful if your screw press isn't large enough to press the whole panel. Use long cauls and press one side, then re-press the other side later. Heated cauls will re-melt the glue and allow it to be clamped tight again.

Banding and a border would be done after the main panel is glued on.

This doesn't necessarily help with solid stock joinery, though.

[Keith Mathewson]

Sorry Mike I wasn't very clear, he has done several vids. Here is one that may be more suited- https://www.youtube.com/watch?v=9hhl9Sp9gVI

[Mike Henderson]

You wouldn't hammer veneer anything that needs to match up like marquetry, 4 way match, etc.

What I've seen done is to do it as quickly as possible, and then use heated cauls in a veneer press. That is, get some 1/4" aluminum to use on the cauls on bottom and top of the veneered panel, then your normal wood cauls. Heat them up so they are fairly warm to the touch with a propane torch/grill/etc. If it's too hot to hold, it's too hot for the veneer. This will reactivate the hide glue while you clamp it down in a screw press. Plus it lengthens the time that the glue cools, so you can readjust if needed. Also useful if your screw press isn't large enough to press the whole panel. Use long cauls and press one side, then re-press the other side later. Heated cauls will re-melt the glue and allow it to be clamped tight again.

Banding and a border would be done after the main panel is glued on.

This doesn't necessarily help with solid stock joinery, though.

Our ancestors did marquetry and things like radial matches. Do you think their process was similar to what you mention? I can visualize large iron plates that were heated before pressing. But iron would rust and could mark the veneer and they didn't have plastic sheet to put between the iron and work.

Any ideas how they might have done those things? I don't think they would glue them up piece-by-piece.

Mike

[Mike Henderson]

Sorry Mike I wasn't very clear, he has done several vids. Here is one that may be more suited- https://www.youtube.com/watch?v=9hhl9Sp9gVI

Thanks. That one was helpful for what I want to do. He does glue up the face piece-by-piece.

Mike

[Robert LaPlaca]

Mike, you might want to check out some of the YouTube videos by Robert Millard, Rob is a pretty well known Federal period furniture builder, is also a member of SAPFM. IIRC Rob had a fairly unique technique to hammer veneering using hot hide glue

[Mike Henderson]

I've been working with hot hide glue when I have time and will give a status report.

The first thing I did was glue some blocks together and then break them apart. The break did not occur on the glue line, indicating that the glue is stronger than the wood.

Then I went to veneer work. I made a panel and tried to hammer veneer it. I had problems with the temperature falling faster than I could squeegee the veneer with my veneer hammer. And I had problems with the veneer not adhering around the edges. The veneer curled a bit around the edges, rising up from the glue. I fixed that by clamping a caul around the edges.

But then I decided to try the hot hide glue with a press in my vacuum press. I heated the substrate with a heat gun and then applied the glue to the substrate and veneer. I scrambled and got it into the press, with a panel caul over the veneer. That came out pretty good.

Then, I did another veneer panel and did the same thing on the back. You can see the results in the pictures. There's no finish on the panels.
328599 328598

I just used some scrap veneer so the panels are not that showy.

The problem I encountered with the "one side at a time" glue up is that the panel warped. When you put a lot of moisture on one side of a 1/4" MDF panel, it warps. When I veneered the other side, it didn't flatten out (yet). I assume this would be true if I had hammer veneered it (still putting a lot of moisture on one side at a time).

My analysis so far:

1. Hide glue is a good strong glue.
2. Having to make up a batch when you want to do a glue up takes time and wastes glue because you have to make more than you need - you can't risk running short. I don't do glue ups every day so any unused glue is discarded (once you make it, it doesn't last unless you refrigerate it). The time to make the glue is inconvenient but not a deal killer.
3. The major problem is that hot hide glue is a hot process. You have to heat your work or it will set too quickly. And that means you have very little open time. Complex glue ups require a lot of planning and maybe some help.
4. The cost of the glue is not too bad.

I'm pretty good by now at estimating how much dry glue to put in the pot for a glue up, so I don't waste a whole lot. Also, as a side note, the glue does not stick to the copper pot so cleanup is easy.

That's about it so far. I'm going to make a box and do all the glue up with hot hide glue so I'll report back later on that.

It's an interesting project. I've always wanted to learn more about hot hide glue.

Mike

[russell lusthaus]

I'm coming into this thread late in the game, but using fish bladder glue crystals mixed with the hide glue crystals, you will get a longer open time. The key, of course, is the mix ratio, which of course is depended on the quality and the type of fish bladder glue used.

Traditionally (in bowyery), sturgeon bladder glue was used. Sturgeon is now a protected species, so obtaining sturgeon bladders or glue crystals is difficult, but not impossible, and I get mine from a guy in France who gets the bladders from Siberia fish farms (so he says). I am told other fish bladders work also, but I have not tried them. China Town where ever you are located may be a place to purchase dried bladders (not sturgeon) as they are sold for soup making.

Keeping everything warm is a must. I get about an hour (a little less) of open time when I mix my sturgeon glue with hide glue at a 12.5% ratio by weight. I have never tested the actual strength of my mix, but a wood to wood bond will not break on the glue line. I mainly use this mix to glue sinew courses to wood, and find I am not rushed. I can provide the name and number of the French guy if anyone wants it. He has a site on the net that he does business thru.

Russ

[Mike Henderson]

I'm coming into this thread late in the game, but using fish bladder glue crystals mixed with the hide glue crystals, you will get a longer open time. The key, of course, is the mix ratio, which of course is depended on the quality and the type of fish bladder glue used.

Traditionally (in bowyery), sturgeon bladder glue was used. Sturgeon is now a protected species, so obtaining sturgeon bladders or glue crystals is difficult, but not impossible, and I get mine from a guy in France who gets the bladders from Siberia fish farms (so he says). I am told other fish bladders work also, but I have not tried them. China Town where ever you are located may be a place to purchase dried bladders (not sturgeon) as they are sold for soup making.

Keeping everything warm is a must. I get about an hour (a little less) of open time when I mix my sturgeon glue with hide glue at a 12.5% ratio by weight. I have never tested the actual strength of my mix, but a wood to wood bond will not break on the glue line. I mainly use this mix to glue sinew courses to wood, and find I am not rushed. I can provide the name and number of the French guy if anyone wants it. He has a site on the net that he does business thru.

Russ
Thanks for the suggestions, Russ. What I'm really trying to do here is better understand what our ancestors did when using hot hide glue - although I cheated and used my vacuum press for pressing the veneer. I'm having trouble keeping the work hot enough in my shop at this time of the year.

If all I was looking for was longer open time in a hide glue, I'd probably just go with liquid hide glue.

I question whether I will continue using hot hide glue - the modern glues are so much easier to use and I can't see any real advantage to hot hide glue at this point of time. If I were to get a restoration where the original used hot hide glue, I'd use it, but for new work, I'll have to reserve judgment until I do more working with it.

Mike

[russell lusthaus]

What I am suggesting is the way our ancestors did it, at least someones ancestors. In my work, I attempt to duplicate the Turkish bows of the past and only use the techniques available and used by the ancients. By no means am I suggesting adding urea to the mix, as that is no different that using a modern glue in my mind. The hide glue I use I make myself from assorted animal hides and hoofs. For most of my needs, the quick open time of the regular hide glue is not limiting me in any real regard, as my glue ups are small. However, there is one glue up I do where I need an open time of about 45 minutes. The only non-modern way I have found is to mix the 2 natural and traditional glues together to get the "best of both worlds". I imagine mixing the fish bladder glue with the hide must make the mix weaker in strength than straight hide, but I have not had any strength problems or de-laminations. I do get the open time I need and I am still able to say (with a straight face) I did this the same way (our ancestors) the mongols of asia did it hundreds of years ago.

If I was not attempting to be traditional in every way (except strings), I would not hesitate to never use hide glue again. Modern glues are so much easier to use.

Russ

[Warren Mickley]

I think that if you are serious about historic practice you ought to look at Roubo, L'art du Menuisier. The third section of part three talks about veneer workers (ebenistes). One technique they used is putting a row of small nails in the background to hold the work against. Here is a plate that illustrates the nails and an iron that they use to warm things up as they work.
328842

Here is some of their work:
328843

[John Vernier]

Jack Plane's Pegs and Tails blog has a brief but useful post about how veneer pins were used to hold veneer elements in place, here:
https://pegsandtails.wordpress.com/2012/01/15/a-thorny-subject/

I Think Patrick Edwards also has written about veneer pins on his blog.

The business about using hot iron plates to press veneer is probably a later 19th-century industrial process, although I haven't pinned down when it was invented. It is described and illustrated in Frank Lister Sutcliffe's The Modern Carpenter Joiner and Cabinetmaker, 1902. (I have the 1990 reprint, It is in the volume titled Craft of Case-Making & Cabinet-Making, p.261-2). What is described is a large iron table with a series of cast iron cauls which screw down along the perimeter, the whole thing heated by gas burners. The whole works would be pre-heated, and once the panel and veneers are laid down and clamped, the gas would be turned off and the press allowed to cool overnight. This means that open time isn't really an issue, although I think this process must have been more practical for large plain panels than for decorative work. Interestingly, the iron plates are described as being covered by zinc sheets. This may just be to protect against rust, but could it also be less likely to stick?

It is certainly interesting how adhesive tape has revolutionized veneer work. That as much as anything has really changed the way the work is approached.

[Mike Henderson]

What I am suggesting is the way our ancestors did it, at least someones ancestors. In my work, I attempt to duplicate the Turkish bows of the past and only use the techniques available and used by the ancients. By no means am I suggesting adding urea to the mix, as that is no different that using a modern glue in my mind. The hide glue I use I make myself from assorted animal hides and hoofs. For most of my needs, the quick open time of the regular hide glue is not limiting me in any real regard, as my glue ups are small. However, there is one glue up I do where I need an open time of about 45 minutes. The only non-modern way I have found is to mix the 2 natural and traditional glues together to get the "best of both worlds". I imagine mixing the fish bladder glue with the hide must make the mix weaker in strength than straight hide, but I have not had any strength problems or de-laminations. I do get the open time I need and I am still able to say (with a straight face) I did this the same way (our ancestors) the mongols of asia did it hundreds of years ago.

If I was not attempting to be traditional in every way (except strings), I would not hesitate to never use hide glue again. Modern glues are so much easier to use.

Russ
It would be interesting to learn more about the Turkish bows you produce. I know the best western bows are often made from pernambuco and that bow making is an art that takes years to master.

Mike

[Max Neu]

Mike,
One method of doing complex designs is using "The assembly board method",that's where you use hide glue and lay out the design on brown kraft paper.Once the design is completed,then you glue it down to the surface,and remove the paper after it dries.I took a 1 day class with Patrick Edwards at Marc Adams school of woodworking on this method.He is a master with Hot hide glue,I think he is the one that came up with old brown glue. The veneering/marquetry he has done with hot hide glue is pretty amazing!

[Mike Henderson]

Mike,
One method of doing complex designs is using "The assembly board method",that's where you use hide glue and lay out the design on brown kraft paper.Once the design is completed,then you glue it down to the surface,and remove the paper after it dries.I took a 1 day class with Patrick Edwards at Marc Adams school of woodworking on this method.He is a master with Hot hide glue,I think he is the one that came up with old brown glue. The veneering/marquetry he has done with hot hide glue is pretty amazing!
That sounds similar, in a way, to how marquetry is done today. When doing marquetry, you take the background and put wide blue tape on the glue face. Then, you can lay each individual piece of the marquetry design into it's place, with it held in place by the blue tape. When completed, you put wide veneer tape over the whole show face and remove the blue tape. After glue up, you can remove the veneer tape with water.

I assume what you would do with hide glue and the brown paper is that you'd glue the paper to the background on the show face. Then as you placed each piece of the marquetry, you'd coat it with hide glue before putting it in place.

One issue is that you're working with a mirror image of the design since you see it from the glue face, while with the blue tape you're working from the show face and see the actual design. But like the old time printers who could read backwards text perfectly, I guess you'd learn how to deal with the mirror image.

I assume that once you get everything laid, you hammer veneer the design onto the substrate. When the glue is set and dried, you might be able to remove the kraft paper with water, or it could be sanded off.

I wonder if our ancestors did this, or if it is a modern invention.

Mike

[Max Neu]

Mike,
I don't think it's a modern invention,most everything Patrick does is from the historical way's.I know it's a French technique,so maybe the American's did it a different way?He said he spent several years studying veneering/marquetry in France,so that's where a lot of his techniques are from. I would visit Patrick's website and watch some of his video's on youtube,that will give you a better idea of the technique.Also,I was picking his brain a little bit about hot hide glue when I was talking to him last year,and he said you should abrade everything with a toothing blade before applying hot hide glue,even rub joints.He definitely knows his stuff,I don't think he even owns a power tool,or a bottle of modern glue.

[Max Neu]

Regarding removing the kraft paper, it comes off with cold water.

[Warren Mickley]

Roubo (1774) illustrates the use of paper for some work. For instance, if a flower made up of many pieces is to be inlaid into a surface, he first glues all the flower pieces together on paper, then tears the paper away around the edges so he can scribe the outline of the flower on the background for the excavation. I don't think he uses paper for work like you have shown, Mike.

[russell lusthaus]

It would be interesting to learn more about the Turkish bows you produce. I know the best western bows are often made from pernambuco and that bow making is an art that takes years to master.

Mike


Hi Mike

While I am merely a student in learning the art of producing the Asian Style / Turkish Bows, there are a number of locations on the web for you explore if you are interested. ATARN is one and for a more general primitive bowmaking, check out Primitive Archer (which is where I often) post, focusing on all types of primitive bows, but mainly the different kinds of American flat bows and English longbows - although there is a sub group for the Horn Bows I mentioned above.

Bow making is definitely an art, and the Asian style bows even more so that the American or English. I have never come across pernambuco so I cant comment on that but I can tell you that Osage and Yew are the two most sought after woods for primitive bowmaking on the left side of the pond. Locust, hickory, and vine maple are some other often used woods.

Russ

[Mike Henderson]

I've read over and over again that you can put finish over hide glue and the hide glue doesn't show. I'm doing a project with hide glue and I got some hide glue on the wood from my fingers - got hide glue on my fingers as I was applying the glue to a joint. When I applied shellac, the hide glue marks were very obvious - they were lighter than the rest of the wood that was finished.

And it seems to me that this would be the case. There should be a difference between the color of wood that absorbs the finish and where the glue is and the finish can't get to the wood.

So what's going on? Why do people claim that you can finish over hide glue and it won't show?

Mike

[Max Neu]

I've read over and over again that you can put finish over hide glue and the hide glue doesn't show. I'm doing a project with hide glue and I got some hide glue on the wood from my fingers - got hide glue on my fingers as I was applying the glue to a joint. When I applied shellac, the hide glue marks were very obvious - they were lighter than the rest of the wood that was finished.

And it seems to me that this would be the case. There should be a difference between the color of wood that absorbs the finish and where the glue is and the finish can't get to the wood.

So what's going on? Why do people claim that you can finish over hide glue and it won't show?

Mike
I have never understood that either,I have never noticed hot hide glue not being visible after a finish is applied on top of it.I have learned to be even more careful with it than pva glue,because not only does it show after the finish, but it's harder to sand off.

[Mike Henderson]

Another issue: I was building a box so that I could work with hot hide glue. I used miter joints, as I have many times with PVA glue, and cut the miters on the Kapex (they were good miters). Glued up the box with hot hide glue. Then I cut the top off and was applying shellac on the inside of the box (I had sanded it earlier). As I was applying the shellac, I heard a "pop". Investigating, I found that one of the miters had come unglued.

I then took a soft hammer and tapped on the inside of the side and broke the other glue joint apart. I've never had that problem with PVA.

Some time back, I was talking with a luthier and asked how he removed the top of a violin or cello. I commented that he couldn't heat the whole joint - and in any case, he'd risk damaging the finish. He told me that he works a pallet knife between the top and side and then works around the top. He said that hide glue does not have good strength in tension so he can usually remove the top without damage.

Mike

[Mel Fulks]

I've been told that the tops for the bowed instruments are glued on with weaker watered down glue so that they can be repaired ,and I have seen a careful and competent repair man easily remove some tops and struggle with others that were clamped to tight ,or with too strong glue ,or both. So I doubt that is comparable to your situation with the box corners. Sometimes the end grain is first "sized" with a coat of hide glue before actual gluing ,but I don't know enough about it to say that was the problem.

[Mike Henderson]

I've been told that the tops for the bowed instruments are glued on with weaker watered down glue so that they can be repaired ,and I have seen a careful and competent repair man easily remove some tops and struggle with others that were clamped to tight ,or with too strong glue ,or both. So I doubt that is comparable to your situation with the box corners. Sometimes the end grain is first "sized" with a coat of hide glue before actual gluing ,but I don't know enough about it to say that was the problem.
Yep, I sized it first.

I wonder if maybe I made the glue too thin. In reading about hide glue, it says to make it where it flows off the brush in a stream and not in "drops". That's the way I had the glue. And it was up to temperature - about 145 degrees F.

Mike

[Max Neu]

I have done quite a bit of testing with hot hide glue,and the more I tested,the less confident I am with it.You don't realize how good PVA glue really is until you spend some time with hot hide glue.I suppose you can make it work for you if you are really determined.

[russell lusthaus]

If memory serves, Fine Wood Working did a glue test a few years back and found Hot Hide Glue stronger than say, the Titebonds. Of course, both are stronger then the wood, so I never really understood the need for the stronger glue - it is the dried glue properties that are important other than its strength ie - its water resistance, its ability to release under heat, its ability to flex or stretch and then return wo cracking, etc. PVAs are great because they are easy to use and are generally water resistant or proof, but they don't release the same as Hide Glue and they do not bond the same way as Hide Glue does to other natural material like horn and sinew, so their use for me is limited to more modern woodworking type projects.

[Mike Henderson]

If memory serves, Fine Wood Working did a glue test a few years back and found Hot Hide Glue stronger than say, the Titebonds. Of course, both are stronger then the wood, so I never really understood the need for the stronger glue - it is the dried glue properties that are important other than its strength ie - its water resistance, its ability to release under heat, its ability to flex or stretch and then return wo cracking, etc. PVAs are great because they are easy to use and are generally water resistant or proof, but they don't release the same as Hide Glue and they do not bond the same way as Hide Glue does to other natural material like horn and sinew, so their use for me is limited to more modern woodworking type projects.

I'm not sure I agree with some of your comments. My understanding is that hide glue is not water resistant - that it will dissolve in water and that's one way people get hide glue joints to release (in addition to heat). Also, from personal experience and from reading, I believe that hide glue will set hard and will not flex. PVA does not set as hard and is designed to give to accommodate some wood movement.

Like almost every product, hide glue has advantages and disadvantages. If the advantages outweigh the disadvantages - for your application - you should use it. If the disadvantages outweigh the advantages, you should not use it.

Mike

[Warren Mickley]

Using hide glue is an art. It is not the kind of thing where you can read the label and follow directions; it is very helpful to have experience seeing skilled workers use it. I was shown how to use hide glue just about fifty years ago by a man whose family started making violins in 1633. And early on I had friends in the restoration business whom I often saw working. This helps one get a feel for how it works. I now use hot hide glue almost exclusively.

Hide glue is also just a lot nicer for repair work: easier to get apart, easier to clean up, easier to reapply glue to old surfaces. If somebody brings me damaged furniture that was put together with PVA or something, I tell them it was not designed to be repaired.

[Max Neu]

I don't think hot hide glue is a good choice for the casual user,I think it takes a long time and full commitment to be consistently successful with it.A few years ago I took a weekend class with David Orth on hot hide glue ,I learned quite a bit from him.He actually recommended not using it unless you have a specific reason to.He also talked about the importance of learning how to repair bad joints,because you will definitely be dealing with them alot more than with modern glues.I just can't get myself to use it,by the time I put alot of time and effort in a project,I don't want to take the risk of having problems with the glue.

[Mike Henderson]

I had a woman bring me a table a few days ago. It looks somewhat like the picture I've included here, but it has two drop down sides. An arm swings out from the leg frame to support each side. The legs splay out as in the picture.

Anyway, her problem was that the boards were coming apart - the glue was just giving up. When I disassembled the table, indeed many of the joints between boards in the table top and sides were just loose - the glue was there but it had deteriorated basically to dust. It was hide glue.

The table was not valuable but it was something she wanted to continue to use and to pass on to her children.

I ran each side of each joint through my jointer and glued it up with PVA. The top and sides are now strong and should last a long while.

But back to hide glue. Suppose I wanted to release two boards where the hide glue had not deteriorated to the point of dust - how would I get the hide glue to release? I really wouldn't want to put a lot of water into the wood and heat could destroy the finish on the table top. Is it possible to get two boards glued together like this apart?

Mike

329442

[Jim Koepke]

I have been reading this thread. Now I am a bit confused.



I really wouldn't want to put a lot of water into the wood and heat could destroy the finish on the table top. Is it possible to get two boards glued together like this apart?


If it were me, worried about the finish, then the last thing I would want to do is separate the boards in the table top. Wouldn't that mess with the finish as much as heat and moisture?

jtk

[Kees Heiden]

I have now completed a few projects with hot hide glue. I like the "witchcraft" of it all, the boiling soup in the cauldron, the funny smells, but also the bit of intelligence you need to get it all working out. It's not overly difficult (I'm not talking about difficult violin making here!) , just a lot more work and it calls for attention all the time. It can get a bit nervous around larger glue ups, but when you can divide the job in many small ones it isn't so bad.

For a quicky job I still prefer the glue in the bottle. And on a hide glue project, when I accidentally bust of a splinter in a corner of my work, I'll likely grab the bottle of PVA too, instead of soaking the glue pearls, boiling up the kettle, etc. Maybe I should make myself a batch of liqued hide glue, so I have something easy in reserve.

[Derek Cohen]

But back to hide glue. Suppose I wanted to release two boards where the hide glue had not deteriorated to the point of dust - how would I get the hide glue to release? I really wouldn't want to put a lot of water into the wood and heat could destroy the finish on the table top. Is it possible to get two boards glued together like this apart?

Hi Mike

A panel split in a recent frame-and-panel, and I needed to repair this before moving on with the build. Fortunately, the mortice and tenon joints were held together with liquid hide glue. I drilled out the pegs, and then steamed the joints - wet cloths and hot air gun. they came apart with a little gentle persuation. That was one of the good parts. The other was that one can use (liquid) hide glue directly over (liquid) hide glue. You cannot do this with other glues, except epoxy.

Regards from London

Derek

[Mike Henderson]

I have been reading this thread. Now I am a bit confused.




If it were me, worried about the finish, then the last thing I would want to do is separate the boards in the table top. Wouldn't that mess with the finish as much as heat and moisture?

jtk

My question was hypothetical - how would you release two boards that were glued together. But in this case, the glue had failed in most of the joints so it was reasonable to expect that the remaining one or two joints would fail within a few years.

So if I wanted to take the remaining couple of joints apart, how would I do it? The only way I can see is to cut them apart, maybe with a track saw carefully aligned along the glue line. But since they're hide glue and hide glue is suppose to be reversible, how would I get them apart without cutting them apart?

What I've heard is that you use moisture and heat to reverse hide glue. I certainly don't want to soak the wood, so that leaves heat. How would I put heat into the joint without ruining the finish?

Mike

[When I reglued the loose boards, I used cauls to flatten the joint. Even with that, the joints were not perfect, close but not perfect, but she was satisfied.]

[Mike Henderson]

But back to hide glue. Suppose I wanted to release two boards where the hide glue had not deteriorated to the point of dust - how would I get the hide glue to release? I really wouldn't want to put a lot of water into the wood and heat could destroy the finish on the table top. Is it possible to get two boards glued together like this apart?

Hi Mike

A panel split in a recent frame-and-panel, and I needed to repair this before moving on with the build. Fortunately, the mortice and tenon joints were held together with liquid hide glue. I drilled out the pegs, and then steamed the joints - wet cloths and hot air gun. they came apart with a little gentle persuasion. That was one of the good parts. The other was that one can use (liquid) hide glue directly over (liquid) hide glue. You cannot do this with other glues, except epoxy.

Regards from London

Derek
Thanks, Derek. My question was how to release a joint of two boards glued together along their length.

Also, polyurethane glue (Gorilla glue) will stick to just about anything, including hide glue and PVA (and epoxy). The disadvantage of polyurethane glue is the foaming. I use poly glue in most "difficult" repairs where I cannot get back to bare wood.

Mike

[Just as a side note, poly glue is great for repairing bubbles in veneer, no matter what glue you used to attach it in the first place. Slit the veneer, work the poly glue under the veneer, put a caul on it and clamp. Usually don't get any foaming in that situation.]

[And a usage note on poly glue: After it sits around it gets pretty thick. To thin it out, put the bottle in a pot of hot water - close to boiling temperature. The heat will thin out the glue, almost to the consistency of water. That makes it easier to work into tight joints.]

[Mike Henderson]

After the glue failure when I tried to use hot hide glue to put together a box, I re-worked all the sides, trimming them back to get to clean wood and re-glued the box with PVA - while observing the process to try to understand why I failed with the hot hide glue.

My conclusion is that my problem was the very short open time of hot hide glue. Putting even a small box together takes time - to apply the glue, to get all the pieces together and then get it into clamps. And since I was using plain miter joints, it takes some fiddling with the clamps to get all the miter joints aligned properly. During that time, the glue needs to be "open" (not set) so that the wood can be moved and adjusted.

Hot hide glue simply does not give that much open time. Most likely, the glue had started to gel while I was putting the clamps on and movement in the joint during clamping broke the glue bond.

Overall, that seems to be the major issue of hot hide glue. It's a good glue in the right situation (and the right joinery), but the very short open time is a real limitation. I've had complex glue ups where I chose an extremely slow epoxy just because it would take a very long time to get the project assembled. I understand that in our ancestors' shops a complex glue up may have involved a group of woodworkers in order to get things assembled before the glue "set" but I'm working alone and don't have that luxury.

Also, while hot hide glue is a good glue, there's nothing about it that is compelling over modern glues. Some people tout the reversibility of hide glue, but I've repaired a lot of furniture that was put together with modern glues. Another claim is that you can finish over hide glue without it showing but my experience is that it does show, very obviously, under a finish

So, overall, I'm glad I had this opportunity to experiment with hot hide glue. I'm sure I'll find opportunities to use hot hide glue in certain situations but I can well understand why our woodworking ancestors switched to modern glues when they became available. Working with hot hide glue is difficult and does not provide any significant advantages over modern glues

Mike

[russell lusthaus]

Mike

You are correct and the way I wrote that does make it seem like I was suggesting that Hide Glue is water proof or resistant. In fact, as you correctly point out, it is definitely not water proof at all and will dissolve away in water. I was clumsily listing the important properties of glue in general that the user must choose between - and its water resistance, in my opinion, is one of the best thing about the titebonds over hide glue. As to flexing - I use hide glue on the back of bows to secure raw hide and sinew - and in this location, the materials are designed to stretch with a properly working bow. As a result, I have always thought hide glue somewhat flexible in that in this use it does not crack, but I am willing to learn if I am mistaken. If mistaken, though, I would need some other explanation why it does not crack on the back of a bow?

Russ

[russell lusthaus]

. . . I know hide glue joints in furniture sometimes come undone or loosen due to the glue taking moisture from the atmosphere . . . and undoing itself . . . .

[Mike Henderson]

Mike

You are correct and the way I wrote that does make it seem like I was suggesting that Hide Glue is water proof or resistant. In fact, as you correctly point out, it is definitely not water proof at all and will dissolve away in water. I was clumsily listing the important properties of glue in general that the user must choose between - and its water resistance, in my opinion, is one of the best thing about the titebonds over hide glue. As to flexing - I use hide glue on the back of bows to secure raw hide and sinew - and in this location, the materials are designed to stretch with a properly working bow. As a result, I have always thought hide glue somewhat flexible in that in this use it does not crack, but I am willing to learn if I am mistaken. If mistaken, though, I would need some other explanation why it does not crack on the back of a bow?

Russ
You make a good point, Russ. All the older hide glue I've seen on old furniture has been pretty hard. When I've had to remove it, it chipped when I worked it with a chisel to remove it. But your example of a bow would contradict the premise that it is not flexible. And nothing is better than actual experience.

Maybe the hide glues that you use and the hide glues I've encountered had different compositions. Or maybe the fact that the glue is flexed throughout it's life on a bow makes a difference - whereas on furniture the glue is not flexed.

Like you, I am willing (and trying) to learn, also.

Mike

[Leo Passant]

Joints glued with animal glue can be dismantled using a combination of heat and moisture, but it does require some effort... they don't just fall apart in a damp atmosphere (https://pegsandtails.wordpress.com/2013/04/07/the-efficacy-of-animal-glue/).

Animal glue can easily be made waterproof (https://pegsandtails.wordpress.com/2009/09/17/glue-not-adhesive/) (if that's really required) and its open time can be extended to five minutes or more with the simple addition of some urea (in the past, cabinetmakers used to make up their glue with stale horse's urine instead of water). I do the vast majority of my work using three parts of glue to one of urea.

[paul cottingham]

I use hot hide glue for pretty much all of my joinery in projects. I still use PVA for quicky joinery on little projects.

Seriously, as i have said many times in the past, i am at best a hack woodworker. And i have little trouble with hide glue.

[Leo Passant]

Another issue: I was building a box so that I could work with hot hide glue. I used miter joints, as I have many times with PVA glue, and cut the miters on the Kapex (they were good miters). Glued up the box with hot hide glue. Then I cut the top off and was applying shellac on the inside of the box (I had sanded it earlier). As I was applying the shellac, I heard a "pop". Investigating, I found that one of the miters had come unglued.

I meant to respond to this comment in my last comment (#71) above, but forgot. Alcohol – as used in your shellac polish – is hygroscopic i.e. it absorbs water from its environment. If the glue you used was too thin or had voids, the polish likely seeped into the joint, sucked the moisture from the glue and the box (under some degree of tension) popped apart.

When heat and water can't be used to separate a glued joint (as when repairing valuable antique chairs), I inject pure alcohol into the joints whereupon the glue becomes anhydrous and crumbles. The chair frame can then be gently tapped apart.

Antique furniture in an overly hot/dry situation can reach a state where the glue dries out and becomes brittle and subsequently fails. This is another reason to include a certain amount of old horse urine (or urea, if you've run out) in all glue applications, as it too is hygroscopic and keeps the glue from drying out.