Official Luthiers Forum!
http://luthiersforum.com/forum/

The awesomeness of hot hide glue
http://luthiersforum.com/forum/viewtopic.php?f=10101&t=26701		 Page 1 of 1
Author:  Corky Long [ Thu Mar 25, 2010 3:29 pm ]
Post subject:  The awesomeness of hot hide glue
I've just gotta share this.

I laminated some necks - 6 pieces, honduran mahogany, maple, ebony, maple, hog. I had some offcuts that weren't of use as anything but some really fancy sanding blocks. So one of them I used for wetsanding my finish - left the laminated block in warm soapy water overnight. The next day - the glued seams were as solid as ever. [clap] This glue is awesome!!!

I'm so glad I can share this with a group of people who don't consider this kind of thing a sign of insanity [:Y:] My wife's supportive, but this one would have gotten the eye roll idunno
Author:  JohnAbercrombie [ Thu Mar 25, 2010 3:37 pm ]
Post subject:  Re: The awesomeness of hot hide glue
I had to remove a (misaligned) top, overnight glued glued with fish glue (similar to HHG) recently.
Even with hot water, hot palette knives, steam iron, etc etc it was a struggle.
So much for low water resistance of fish (and hot hide) glue!
When people talk about the 'repairability' of these glues I think they are talking about the fact that the glue will stick to itself, not the ease of separation!
A word to the wise- consider these joints 'almost-permanent' and double check the alignment before going to bed!

Cheers
John
Author:  bluescreek [ Thu Mar 25, 2010 4:07 pm ]
Post subject:  Re: The awesomeness of hot hide glue
I don't know much about the fish glue but HHG will separate well but you do need to get it hot enough. Also you keep wax paper handy so it won't restick to itself.
Author:  coke_zero [ Thu Mar 25, 2010 7:23 pm ]
Post subject:  Re: The awesomeness of hot hide glue
I was considering using HHG for my second build to compare it to the glue I am using for my first. What is an easy way to keep it at the required tempterature without having to go out and buy one of those thermostatic glue pots? Also what is the shelf life of the stuff once heated up, i.e if I used it, could I let it cool down and reheat it over and over day after day?
Author:  DennisK [ Thu Mar 25, 2010 8:13 pm ]
Post subject:  Re: The awesomeness of hot hide glue
Yeah, hot hide glue is great stuff. Nice to know that it doesn't mind water. There's a neat page on frets.com here testing hide glue versus titebond under heat stress, and the hide was pretty much heat proof as well. I guess as long as you don't get it hot and wet at the same time, it's one of the toughest glues there is.

My main problem with it is how fast it cools down and gels once it gets spread out. I usually wet both surfaces a bit with hot water, slop glue on one of them, spread it around with a finger, slide the pieces together a bit to spread the glue on both surfaces, quickly wipe the finger I used to spread the glue (while holding the joint), and then get the clamps on. Time from glue leaving the cup to getting the joint rubbed together can only be a few seconds or it turns into a bouncy jello layer between the surfaces. Maybe I need to add more water, or more heat, or use an iron or something to warm the surface before applying the glue.

And yes, you can reheat it as many times as you want. I keep it in a plastic bag in the fridge for up to a week or so, but I've never seen it visibly go bad even after I left a bit in there for over a month. Never tried gluing a joint with that though.

For heating, I just put a pan of water on the stove with a candy thermometer in it, and float a disposable cup of glue in that. Then you can take the pan with you and it stays hot enough for a couple minutes. Easy, no clean up, and free if you already have the thermometer :)
Author:  richaltieri [ Thu Mar 25, 2010 8:22 pm ]
Post subject:  Re: The awesomeness of hot hide glue
Maybe a dumb question but wondering how you mix it. I bought some from LMII a while back and last night was going to mix with water but the directions said to weigh instead and recommended 1:2 mixture. I dont have a scale at the moment so wondering if anyone has a formula of tablespoons to pint or something like that. Thanks
Author:  WaddyThomson [ Thu Mar 25, 2010 8:46 pm ]
Post subject:  Re: The awesomeness of hot hide glue
Generally, you can put some in a jar or tumbler, and just cover it fully with water, and you'll be pretty close. Make sure the glue is all wet, and doesn't block the water from getting to the bottom of the container. When done, the water should just fully cover the glue, When absorbed, there won't be water on the top. Then heat the glue let it cool, then the next time it's heated, it's ready to go. If you have glue already made up and heated, you can just add the wet glue to the mix.
Author:  DennisK [ Thu Mar 25, 2010 8:50 pm ]
Post subject:  Re: The awesomeness of hot hide glue
I should measure the volume proportion sometime, but what I do is make a cave man scale. Just use my 24 inch ruler or a board or whatever, and balance it on something. Get the board centered, then put the empty containers near the ends and mark where they go when it balances, then add the amount of glue I want to one, and fill the other with water until it balances again.
Author:  Chris Beebe [ Thu Mar 25, 2010 10:01 pm ]
Post subject:  Re: The awesomeness of hot hide glue
When I first started using HHG I measured and weighed everything, now I wing it. Fill a container half-full of glue, cover the glue with water, after the water is soaked up cook the glue in some sort of double-boiler. I find that the glue works best if I lift the glue brush out of the pot and the glue creates a steady stream for about 12" before breaking up into droplets, if it's to thick add water, if it's to thin let it cook awhile.
Author:  mhammond [ Thu Mar 25, 2010 10:38 pm ]
Post subject:  Re: The awesomeness of hot hide glue
5 measures of glue (volume) with 9 measures of water will get you in the ball park. After that its your personal preference. I like mine just a little watery..... Mikey
Author:  Corky Long [ Fri Mar 26, 2010 9:11 am ]
Post subject:  Re: The awesomeness of hot hide glue
coke_zero wrote:
I was considering using HHG for my second build to compare it to the glue I am using for my first. What is an easy way to keep it at the required tempterature without having to go out and buy one of those thermostatic glue pots? Also what is the shelf life of the stuff once heated up, i.e if I used it, could I let it cool down and reheat it over and over day after day?


As for the shelf life, I've managed to reheat maybe 10 times before it was used up. As long as you don't let it get too hot, (apparently it starts to break down at anything above 145 degreed F - I'm sure there's a logarithmic scale there somewhere) - I use a $15 digital thermometer with an alarm set at 145. works great. I keep mine in the fridge between uses. At room temperature it will start to mold - it is food (gelatine), after all.

Although the pan in the double boiler approach works, I had trouble maintaining temperature control, and evaporation was too quick for me. Here's what I did, instead of buying an expensive glue pot - and my homemade version works great.

Bought a one-burner hotpot. Took apart a camping coffeepot (any metal tall pot will do) Filled the bottom with glass marbles (slows the temperature change in the water). I use a plastic squeeze bottle for my glue, once mixed. I cut a hole in a thick plastic lid to place over the top of the coffeepot, through which to place the plastic glue bottle. With water in the coffee pot and the hotplate on the "w" of warm (obviously you'd need to figure the appropriate setting on yours), the temperature stays right about 140 - 145. With the glue in the squeezebottle, it doesn't evaporate. Oh yeah - my thermometer also has a hole in the plastic top. So, technically, I monitor the temp of the water surrounding the glue, and not the glue itself. Sorry - no pictures - camera's not cooperating, but it's a very simple setup.

One thing I've also learned is critical when I use HHG is to heat the pieces being glued. I work in my basement in a marginally heated space. The glue gels too fast if I spread it on a cool surface. With my cheap paint remover heat gun - it gets things plenty hot to allow sufficient gelling times before clamping.

Oh, and the final benefit to Hot Hide Glue - that wet dog smell you get when you use it. :mrgreen: Frankly I don't mind it a bit, especially compared to the smell of cutting bone for nuts and saddles!! [xx(]
Author:  WaddyThomson [ Fri Mar 26, 2010 9:57 am ]
Post subject:  Re: The awesomeness of hot hide glue
Here is a really good video that was posted on ANZLF that takes the mystery out of HHG. It eliminates some of the "concerns" we're always expressing. http://woodtreks.com/animal-protein-hid ... tory/1549/
Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/