Cheap Hide Glue set up

[David Ragan]

I picked up these two items @ WM the other day. Had already tried a baby bottle warmer-a disaster. Full on boil, and even w variable temp, they shut off after a few minutes.

So, the item on the right, the 'hot pot' even on warm, it boil the water, then shut off is how it worked. The temp was ~160*. Too hot for the window of 140-150.

So, the little crock pot ($9) is undergoing testing.

What you see is a metal coffee can, and a 1/2" Styrofoam top over the crockpot insert secured w heavy foil air duct tape.

The water in the insert is near the top, and about 1:10 bleach. There is an access plug in the back.

I had to add a variable rheostat as you can see.

Currently, the temp w rheostat set at about 3-4 oclock is from 135-141*. Anything else is outside of the range.

Takes about 4 hours for the thing to warm up.
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So, there is a lot of waste, and adding water to the HHG whilst cooking it, so I started looking around on Amazon for small squeeze bottles w a wide outlet.

What I came up w is taking a syringe, cutting off the hub, and enlarging the opening for a small stopper:



011.JPGA reamer was used to ensure a round opening-so far no leakage.

That is a 20 ml syringe, there is 12gm of 192 in it w 15 ml water.

No adding water, no stirring.

Thoughts?

[Dan Barr]

Not sure what the question is...? Are you asking what the best setup is or the best way to apply the glue? I use a q-tip, acid brush or larger brush to apply. Use a cooking thermometer to calibrate your reostat. Scribe a line on the reostat dial markings once you get to a certain temp. I use the cast iron double pot, not sure I can be any help considering your setup.

[David Ragan]

Not sure what the question is...? Are you asking what the best setup is or the best way to apply the glue? I use a q-tip, acid brush or larger brush to apply. Use a cooking thermometer to calibrate your reostat. Scribe a line on the reostat dial markings once you get to a certain temp. I use the cast iron double pot, not sure I can be any help considering your setup.

Thanks for your reply Dan.

Yes, that is my question.

The brush method, w my skill level, is pretty sloppy.

Plus, I tired of having to check consistency of the glue, add water, etc---all that led to it getting on things it wasn't supposed to.

Thus, the enclosed dispensing system.

FWW had an article by Roland Johnson about using a wax melter--so that is undergoing testing now. I promised my wife a newer, better one. It looks promising, so I packed up the mini crockpot/rheostat.

[Mike Henderson]

Interesting idea. The biggest problem I had with hot hide glue was having it cool on the wood before I could get the glue applied to all the places I needed to and the joint together. Anything that speeds up the operation would be good. Keep us informed as to your progress.

I used brushes.

Mike

[Getting dovetails together was almost impossible for me. I never tried it, but maybe having someone else use a heat gun on the joint while I was applying the hide glue would have helped.]

[Bob Glenn]

I just use a four dollar mini crockpot. I put my glue beads in a small jar then use hot water from the faucet for the glue and crock. Cover the pot and plug it in. The glue is ready in less than an hour. I used a candy thermometer and found the low setting to be right at 140 F. I think this whole hot hide glue thing has been over analyzed. I find it very easy to use especially for rub joints, but you have to be quick. For longer glue ups I use liquid hide glue. I don't even have any white or yellow glue in the shop anymore.
As for application, I use an appropriate sized brush. Thinning the hot glue makes is easier to spread and gives you more open time. Clean up is easy with a little hot water and an old tooth brush.

[David Ragan]

Interesting idea. The biggest problem I had with hot hide glue was having it cool on the wood before I could get the glue applied to all the places I needed to and the joint together. Anything that speeds up the operation would be good. Keep us informed as to your progress.

I used brushes.

Mike

[Getting dovetails together was almost impossible for me. I never tried it, but maybe having someone else use a heat gun on the joint while I was applying the hide glue would have helped.]

From what I have read, Mike, HHG does not cause the joint to swell, and makes it more slippery.

My experience in this area is limited, but-for Bubbles' urn (see Project thread) I thoroughly heated the wood (electric blanketx2 hours or so), and I had to apply clamps, I thought it would never cool down; unbelievably slippery. Therefore, this method of heating joints is overkill. Most folks use heat lamps/guns.

HHG is the original 'rub joint' where clamping is not necessary.

One variable still need to work out is whether the 192 @ 145* will come out of the stock syringe opening easily. I suspect that it will-that me cutting off the stock outlet was unnecessary.

Following my reinventing the wheel, looks like the following is going to win out.

(The little LV glue pot, while a good idea, and cute, had no precise temp control, and the inherent liability of the open pot.)

Please recall that methods tried have been:

-LV miniature glue pot
-water bath on top of LV miniature hot plate
-Baby bottle warmer (unable to find one w variable temp setting that stayed on forever)
-'hot pot'
-mini crock pot

I suspect that a full size variable temp hot plate w water bath would also work well, especially if large amount of HHG needed.




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[Robert LaPlaca]

David, a couple of thoughts;

I suggested using a Rival Hot Pot express in another thread about inexpensive hide glue pots, it is true the hot pot will start off way too hot during the initial start-up, but after the thermostat has a chance to work you will find the tempurature does stabilize. I don't place any glue to be heated into the bath until the tempurature does stabilize, hence the suggestion for a accurate thermometer. I also found it helpful to place some small clean rocks into the bottom of the Hot Pot, the extra mass helps to keep the tempurature stable, as does the largest volume of water in the bath.

It's very true that very tight dovetail joints will be a breeze to glue with hide glue, because of the slippery nature of the glue, the same joint glue with yellow glue will make you miserable.

[Mike Henderson]

From what I have read, Mike, HHG does not cause the joint to swell, and makes it more slippery.

The problem I was having is that the HHG would cool on the wood and congeal before I could get it together, not that the HHG kept the joint from going together. I discovered that you really have to keep everything pretty warm when doing a glue up - and work very fast.

But HHG is water based and that would cause wood to swell, just like any other water based glue - if that was a problem for you. HHG certainly can cause veneer to expand when you use it to attach the veneer. You see it more with rotary cut veneers, like waterfall bubinga, than quarter cut or even face cut. A lot depends on the veneer, itself.

Mike

[The other issue is that hide glue can certainly show under a finish. We often hear that you can finish over hide glue but that must mean that if you spread hide glue over the whole surface you can finish over it because if you have spots where the you got hide glue on the wood, it will show under a finish in the same was as PVA glue will show. Being under the impression that hide glue would not show, I handled some wood while I had hide glue on my fingers. Sure enough, I had fingerprints under the finish and had to strip and sand it off.]

[David Ragan]

The problem I was having is that the HHG would cool on the wood and congeal before I could get it together, not that the HHG kept the joint from going together. I discovered that you really have to keep everything pretty warm when doing a glue up - and work very fast.

But HHG is water based and that would cause wood to swell, just like any other water based glue - if that was a problem for you. HHG certainly can cause veneer to expand when you use it to attach the veneer. You see it more with rotary cut veneers, like waterfall bubinga, than quarter cut or even face cut. A lot depends on the veneer, itself.

Mike

[The other issue is that hide glue can certainly show under a finish. We often hear that you can finish over hide glue but that must mean that if you spread hide glue over the whole surface you can finish over it because if you have spots where the you got hide glue on the wood, it will show under a finish in the same was as PVA glue will show. Being under the impression that hide glue would not show, I handled some wood while I had hide glue on my fingers. Sure enough, I had fingerprints under the finish and had to strip and sand it off.]

Indeed, Mike, I must say honestly that using HHG to glue up something like multiple dovetails would keep me up @ night trying to figure out a work-around.

You would think that any swelling would be especially problematic for stringing. However, it has not been a problem for me. The congealing may be the very quality that keeps the water in the glue (i.e., any free water is incorporated into the congealing glue faster than can move over into the wood.)

Rotary cut bubinga? That is way over my head. I'm guessing the cellular structure is more open? Rotary cut would be more along the lines of early/late wood....

And finally-the idea that certain things don't show under finishes has made me wonder. Seems logical that, since HHG is used as a sealant, etc, that anywhere it is you'd be able to tell it. Just like a type of glue that was supposed to be invisible under finishes because it has wood fibers in it. Huh?

Now-as far as squeeze out, HHG is a breeze. within a few minutes, it just rolls up under a finger and leaves no trace.

[Stewie Simpson]

Paul Sellers wrote an interesting article on Titebond Liquid Hide Glue.

https://paulsellers.com/2013/04/tite...uid-hide-glue/

[Eric Keller]

I think a lot of people heat the work pieces when they use hide glue. My shop is cold, I need to set up my blanket heaters, because I have problems with the glue setting up too quickly. I guess you can also use urea

[Mel Fulks]

Yeah. The local (now gone) antique repro company had large steel topped heated tables to warm and keep warm. Great place for lunchtime nap

[John Vernier]

Charles Hayward wrote an autobiographical article, and he recalled working in a client's house on some joinery work before WWI. The workmen lit a fire in a fireplace to heat their glue pot and to warm the ends of the pieces to be glued. He makes it sound like it was standard practice.

[Mike Henderson]

Rotary cut bubinga? That is way over my head. I'm guessing the cellular structure is more open? Rotary cut would be more along the lines of early/late wood....

Looking at a log, end on, the wood expands and contracts around the circumference. That's why logs split as they dry - the outside shrinks more than the inside. We cut logs in half, along the pith before drying to try to minimize splitting. After letting the half log dry, when you come back to it, what used to be the flat part is no longer flat. The outside has shrunk more than the inside of the tree and the "flat part" is now sort of a "V" with the center high.

When you saw wood, a flat sawn board will shrink more across it's width than a quarter sawn board because the quarter sawn board used to run from the outside of the tree to the inside while the flat sawn board ran "sort of" around the tree.

Rotary cut veneer is cut the way is sounds - around the tree. And that's the wood that is most susceptible to expansion and contraction with changes in moisture. So when working with rotary cut veneer, you have to be aware that the veneer will expand as it absorbs moisture. Gluing it with something like PVA (water based) or hide glue (also water based) will cause the veneer to expand.

The expansion is more of a problem with certain veneer designs. A 360 degree radial match made from 8 or more pieces can be almost impossible to get into press without warping if a water based glue is used. The safest approach is to use a non-water based glue for those.

Hope that explains it.

Mike

[David Ragan]

Looking at a log, end on, the wood expands and contracts around the circumference. That's why logs split as they dry - the outside shrinks more than the inside. We cut logs in half, along the pith before drying to try to minimize splitting. After letting the half log dry, when you come back to it, what used to be the flat part is no longer flat. The outside has shrunk more than the inside of the tree and the "flat part" is now sort of a "V" with the center high.

When you saw wood, a flat sawn board will shrink more across it's width than a quarter sawn board because the quarter sawn board used to run from the outside of the tree to the inside while the flat sawn board ran "sort of" around the tree.

Rotary cut veneer is cut the way is sounds - around the tree. And that's the wood that is most susceptible to expansion and contraction with changes in moisture. So when working with rotary cut veneer, you have to be aware that the veneer will expand as it absorbs moisture. Gluing it with something like PVA (water based) or hide glue (also water based) will cause the veneer to expand.

The expansion is more of a problem with certain veneer designs. A 360 degree radial match made from 8 or more pieces can be almost impossible to get into press without warping if a water based glue is used. The safest approach is to use a non-water based glue for those.

Hope that explains it.

Mike

Hi Mike-I always just imagined that the periods of early, and late wood, each an annual cycle, were trying to straighten out, ie, lay out flat-as opposed to being bound up circling a tree.

So-HHG makes all this veneer configurations easier? I hope so, just ordered 10lb from Highland Woodworking. (That way, I don't have to be concerned about batch to batch variation in regards to exact properties for water, etc)

David, a couple of thoughts;

I suggested using a Rival Hot Pot express in another thread about inexpensive hide glue pots, it is true the hot pot will start off way too hot during the initial start-up, but after the thermostat has a chance to work you will find the tempurature does stabilize. I don't place any glue to be heated into the bath until the tempurature does stabilize, hence the suggestion for a accurate thermometer. I also found it helpful to place some small clean rocks into the bottom of the Hot Pot, the extra mass helps to keep the tempurature stable, as does the largest volume of water in the bath.

It's very true that very tight dovetail joints will be a breeze to glue with hide glue, because of the slippery nature of the glue, the same joint glue with yellow glue will make you miserable.

Hi Robert-I had to revisit the entire topic on account of wanting to use a pyrex beaker instead of a Ball jar. Unfortunately, the pyrex beaker was too tight a fit, and did not allow but a minute amount of water in the wax melter-which would evaporate way too quick. Heating the beaker in dry wax melter did not do it at all. Not good contact between heat element/beaker bottom.

So, back to square one-the hot pot? the thing cycled on @ minimal temperature of 150*F on "warm".

So, I brought the variable rheostat back out. Same thing, as soon as the temp of water in the hot pot dropped to 150*, it came back on no matter how little current I gave it. My target for HHG is 140*. I was fairly disappointed.

Then, I got out the hot plate warmer, and sat the beaker assembly on it......turns out w the temp dial at ~4:30, the beaker (w everything in it) will hover around 140*. All this was worked out over about 8 hours this last weekend. The surface temp of the hot plate had to be 275-300* for the water/HHG to achieve 140*

Of course, now, I'm thinking maybe the HHG $150 pot aint such a bad deal. But, you can't vary the temp there, right?

What temp do those things run at?