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:



350540A 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/titebond-liquid-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?

[Mike Henderson]

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)

Doing veneer with hot hide glue (hammer veneering) is very different from vacuum pressing. One problem that I was attempting to alert you to is that certain veneers are not well behaved when worked with hot hide glue because of the water content in the glue.

Pressing veneer with hot hide glue is a special skill. You may like it, or you may not.

The commercial glue pots regulate the temperature pretty well. I'd have to go look at the documentation but 140 degrees sticks in my head. I tried putting water in the pot, then the hot hide glue in a glass jar sitting in the water. Other people have reported good results with that, but I had problems. The glue in the jar just wouldn't get hot enough. Maybe if I left it sit longer it might have worked. People do that when they only want to mix up a small amount of hot hide glue. I just put it in the pot and worked it from there. It's not hard to clean the pot - the glue is water soluble and cleans up pretty easy.

Mike

[Robert LaPlaca]

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?

David,

My Hot Pot Express is about 6 years old, I know at the minimal setting (leftmost) the water temperature is about 120F, too cold for 192 gram HHG, but ok for something like Olde Brown Glue. Maybe Rival made a change in the thermostat for the device? Obviously, the best device would be a true HHG pot and in all honesty as much as I use HHG I should really spring for one.

[Don Parker]

I work with hot hide glue a lot. A few suggestions:

1. An inexpensive way to hit the right temperature is to buy just a regular spiral heating element hot plate with a continuously variable temperature control and use that as the heat source. I used to just heat a shallow pan of water on the hot plate, then put a smaller container of glue into the pan of water to work as a double boiler. Stick a thermometer down in the glue, and fiddle with the control to get the temperature of the glue to stay around 140-145 F.

2. In general, double boiling is a good way to keep the temperature of the glue where you want it, rather than direct heat sources.

3. Nowadays, since I work with hot hide glue so much, I use a fancy brass double boiler on a laboratory student hot plate. The lab hot plate holds the temperature exactly where I want it, and the double boiler holds the perfect amount of glue. It is made by Music Caravan.

4. If you are having trouble with the glue getting everywhere, maybe thicken it up a bit. If you are using 2 parts of water to 1 part dry glue, that is too thin for many tasks. I actually work with a 1 to 1.8 ratio, and it is less runny. You can always thin it out with a little more water.

5. If you need to extend the gel time of the glue, you can add either urea or table salt to the glue. Small amounts extend the gel time a little; larger amounts turn it into the equivalent of Old Brown Glue, and it will stay liquid at room temperature. When I have an assembly that will take a few minutes, adding some urea gives me the additional time, and small amounts won't significantly hurt the holding power of the glue.

6. Clean squeeze out as soon as you can, using a hot damp rag. If there are large amounts, you can easily scrape up the boogers, then wipe the workpiece with the damp rag to get the rest. This stuff dries out pretty fast, so I try to clean up the squeeze out in less than a half hour after assembly.

7. What you describe about making the glue sounds a bit off. Making it is simple: soak the dry glue in the amount of water you want, wait until the water is all soaked into the dry glue ( should be a gelatinous blob), then heat to the right temperature. Boom, it's glue. It takes me a half hour to go from dry glue to hot hide glue: 15 minutes to soak, 15 minutes to heat it up.

Good luck with it moving forward.

[David Ragan]

I started this thread in January, and would like to post what I wound up with.

Sorry about the lengthy post:

During this process, all possible suggestions were tried,

Please note in the photo below, the use of a variable rheostat-(IIRC, temp was too hot) ---didn't work, though

Here you have the mini-crock pot, and over to the right, a Proctor-Silex hot pot---both had great potential because of being hard to tip over/come-a-loose; however, ultimately, inability to control the temperature meant death for these two-somewhat surprising and disappointing.

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Next, the precariously tall and somewhat hazardous hot plate/double boiler method. I threw that out-the double boiler and hot plate would have required me to construct a special box to house it into one cohesive unit (too much chance of boiler/hot plate becoming uncoupled/tip over...I'm a klutz.)

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The next two pictures is what I settled on. A wax melter:

The only issue here was the very small space surrounding the beaker in the melter. The water evaporated too quickly. I needed something that would not evaporate, but transmit heat efficiently to the beaker.

A friend is a chemist, and he said the best thing to use in the space (which was ~2.3mm around) would be salt or sand. Since I wanted maximal transfer of heat into the beaker, not just from the bottom.

The picture below is just after hot hobby glueing of 3/32" brass rods on all sides of beaker to center it in pot.

I put a little salt in the beaker bottom, put centered beaker in wax melter, then salt around that.


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Then, sealed the whole contraption in that hand held shrink wrap stuff (great stuff). That holds it all together, as can be seen in last photo.

1) After some thinking about the ways I could screw this up, I changed out the salt for laboratory grade super fine sand-if water got into this area, salt of course, would dissolve.
2) temperature (I can say after many months) variable w desirable 135-140* in middle of range of source
3) once set up, no maintenance besides the water.
4) The plastic bag/rubber band addition is to slow heat loss via evaporation-less adding water to the beaker.

Final set up as it is today:
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It is ugly---I just didn't want to spend >$100 for a glue pot.

The syringes work great. No evaporation, so no adding water to glue needed over time. 5% urea added gives me more open time.

You can see a temp scale below heat slider bar.

Also, in regards to actual application-I like the syringe method (no needle), very little dribbling glue all over; using a smaller syringe allows precise application for stringing.


Feedback?

[Jim Koepke]

Great solution, thanks for getting back to us.

Where did you purchase your wax melter set up?

jtk

[Todd Stock]

Two Hold-Heet pots with scrap cutting board (LDPE) inserts hold my two ounce squeeze bottle and 8 ounce jelly jar...the insert is the trick to keeping the glue at 140-145...tight fitting opening keeps the glue container suspended and water from evaporating. For large glue-ups, a Rival hot pot provides hot water for clean-up and another gram strength of glue if we have a couple folks in the shop and we need the stronger glue for high stress glue-ups. Don has the flick on mixing glue - not complicated...cover with water, let it suck up as much water (distilled for me) as it can, then heat. We make free use of heat guns to keep things warm and the glue above gel temp, but for smaller stuff, a Saltan plate warmer of the type seen at every 50's/early 60's dinner party is a good bet and available on eBay.

Making up glue for the day is usually delegated to whichever student is in on the weekends (we keep the batch for a week), although I have been known to exchange the glue making chores for fresh lemon bars.

[Jason Dean]

I mix my hide glue up in an empty ketchup bottle (Thanks Don Williams) then heat it in an old style crock pot full of water set on high. The temperature is controlled using one of these:
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Its a digitally programmable thermostat with relayed outputs for heating and cooling with a temperature probe for feedback. You drop the temperature probe in your water bath with the glue bottle and set the thermostat for your desired hold temperature.

[David Ragan]

It is a little embarrassing to put information out there as having been taken as The Best/Only Way to do something.

There are no doubt many ways to accomplish this task; I suppose it all depends on what products we have access to, and our personal dis/likes.

It is very cool to exchange all the different ways of doing things :)

"YMMV"



Great solution, thanks for getting back to us.

Where did you purchase your wax melter set up?

jtk

Hey Jim-there is a Sally Beauty Supply up the road. Any wax melter should do-the holding area is standardized in the industry. They all "should" have variable temp


I mix my hide glue up in an empty ketchup bottle (Thanks Don Williams) then heat it in an old style crock pot full of water set on high. The temperature is controlled using one of these:
367341
Its a digitally programmable thermostat with relayed outputs for heating and cooling with a temperature probe for feedback. You drop the temperature probe in your water bath with the glue bottle and set the thermostat for your desired hold temperature.

Excellent-just put on my wish Amazon wish list; I had no idea.

Have you observed how high/low from set temp it goes before it kicks in?

[Jason Dean]

David,

The threshold for the temperature change is programmable as well. I set mine at 1 degree. This wasn't verified with another thermometer, but the device at least agrees with itself.

[Bruce Willman]

Here is a video about Hot Hide Glue, made by Frank Strazza:
https://www.youtube.com/watch?v=T1CRfPIvAeA

He talks about using Urea to extend open time.