Rub Joint

[ken hatch]

It is the middle of the night, MsBubba is sleeping so time in the shop is quiet time and there ain't much in the shop that is quiet. I did mark out the feet for the new kitchen table which led to some head scratching. My stock is 8/4 Alder and my question is do I glue up the 8/4 stock to make 16/4 feet, go to the wood store for some 4/4 stock to make 12/4 feet, or just use the 8/4 for the base feet. Right now I'm leaning towards 16/4 base units my only concern is making the base too heavy looking.

Yesterday I had the glue pot full of glue and nothing to glue. What to do, what to do. I know, do a rub joint to demo how well one works with hot hide glue. After a little scrounging around in the cutoff pile I found a short Beech cutoff that looked like it had one edge planed. I split it, slopped some hot hide glue on both edges and rubbed them together and then held it for a minute or so before setting aside.

Tonight I cleaned up the faces and tried to break the bond with no joy. I expect if I took a lumpy after it it would break but then with a lumpy I can break any joint.

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ken

[David Eisenhauer]

I have prior experience with hot hide glue rub joints and they do work as advertised. My main comment on hot hide (and to an extent, LHG) glue is that it is a very, very sticky operation and can create a mess from Hell if you don't approach the operation with a pre thought out plan to keep the sticky mess confined to designated areas, tools, personnel, etc.

[ken hatch]

I have prior experience with hot hide glue rub joints and they do work as advertised. My main comment on hot hide (and to an extent, LHG) glue is that it is a very, very sticky operation and can create a mess from Hell if you don't approach the operation with a pre thought out plan to keep the sticky mess confined to designated areas, tools, personnel, etc.

David,

From TFSM lips to your ear, ain't that the truth :). But it does clean up.

ken

[Mike Allen1010]

Ken, thanks for sharing your rub joint experience. I'm a pretty inpatient guy and have recently been experimenting with cryocnate (super glue) for a small panel glue up I didn't want to wait for - can't really tell if i t's solid. Maybe I should try the hot hide glue. what do you use to keep it warm? a dedicate glue pot has always been a "sticking" point for me:) -seems like requires some pre-plannning. what do you do with the glue when your done with current project?

Cheers, Mike

BTW- COVID has regrettably closed my favorite dive taquiria's AND my favorite sport bars - big part of my daily itinerary is now out of the question. Not in any way complaining -I'm clearly not remotely "essential" and appreciate all those doing battle for all of us on a daily basis- THANK YOU!

[ken hatch]

Ken, thanks for sharing your rub joint experience. I'm a pretty inpatient guy and have recently been experimenting with cryocnate (super glue) for a small panel glue up I didn't want to wait for - can't really tell if i t's solid. Maybe I should try the hot hide glue. what do you use to keep it warm? a dedicate glue pot has always been a "sticking" point for me:) -seems like requires some pre-plannning. what do you do with the glue when your done with current project?

Cheers, Mike

BTW- COVID has regrettably closed my favorite dive taquiria's AND my favorite sport bars - big part of my daily itinerary is now out of the question. Not in any way complaining -I'm clearly not remotely "essential" and appreciate all those doing battle for all of us on a daily basis- THANK YOU!

Mike,

I have a glue pot from TFWW but just about any double boiler will work. As for pre-planning I just turn the glue pot on when I walk into the shop and turn it off when I close up the shop. If I use it great, if not it will keep. You have the hide glue expert there in San Diego, Patrick Edwards (the maker of Old Brown Glue) has a store front down by the harbor. I've never gone in but I've walked by it a few times. Long open time you want liquid hide glue (Old Brown Glue), rub joints, short open time, with minimum clamps you want Hot Hide glue. Both have their use.

Yeah, I have the time off, MsBubba and I have talked about going somewhere and San Diego is always the top of the list but what would we do once there, social distancing puts visiting you out as well as tacos and beer so we end up staying at home and working in the shop and on the house. Which ain't all bad.

Take care and be safe,

ken

[Mike Henderson]

I have prior experience with hot hide glue rub joints and they do work as advertised. My main comment on hot hide (and to an extent, LHG) glue is that it is a very, very sticky operation and can create a mess from Hell if you don't approach the operation with a pre thought out plan to keep the sticky mess confined to designated areas, tools, personnel, etc.

I have some experience with hot hide glue and have had mixed results. The real problem is keeping everything warm enough when doing a more complex glue up. If the glue cools to a certain point you get a poor glue joint. I don't know how our ancestors did dovetail joints with hot hide glue. A lot of urea I suppose.

Other problems are that it takes time to get the glue hot before you can do any glueing, and the glue only keeps for a certain length of time before it spoils. Some people object to the odor but I never found that to be a problem.

When modern glues became available, even urea formaldehyde, woodworkers switched en masse and I understand why. I still have my glue pot but I don't use it any more.

Mike

[James Pallas]

I have used HHG, LHG, and wood glue for rub joints. I especially like to use rub joints for work that is difficult to clamp and for thin panels. The hard part for me is to find a place to set things so they don’t get knocked around. It always amazes me how stuck together the objects are after the rubbing is done.

[chris carter]

I use a baby bottle warmer for my hide glue. First time I used it I used a instant read thermometer to keep track of the temp and then I put a little mark on the knob for the "magic spot." It works great, super consistent, and was cheap ($25?? can't remember). A baby food jar also makes for a convenient glue pot for joints. If I need a lot more glue I use an old spice bottle that is less convenient, but holds a lot more glue. I make a big batch of glue in the kitchen and pour it into ice cube molds. Then I keep the frozen cubes in an airtight container in the freezer. Basically, I put a couple cubes in the bottle warmer while I do my practice run of clamping and by the time I'm ready for the glue, the glue is ready.

[ken hatch]

I use a baby bottle warmer for my hide glue. First time I used it I used a instant read thermometer to keep track of the temp and then I put a little mark on the knob for the "magic spot." It works great, super consistent, and was cheap ($25?? can't remember). A baby food jar also makes for a convenient glue pot for joints. If I need a lot more glue I use an old spice bottle that is less convenient, but holds a lot more glue. I make a big batch of glue in the kitchen and pour it into ice cube molds. Then I keep the frozen cubes in an airtight container in the freezer. Basically, I put a couple cubes in the bottle warmer while I do my practice run of clamping and by the time I'm ready for the glue, the glue is ready.

Chris,

Ingenious and cheaper than my glue pot :). I know some folks say hide glue spoils quickly, that can be true if you do not care for it properly but used correctly spoilage is not a problem. Your way is one way, another is to just turn the glue pot on every day when you walk into the shop. That also takes care of the time needed to get the glue ready to use. If you are not going to use the glue for an extended period you can dry it out by drying on screens then treat the dried hunk of glue just like you would granular hide glue.

Most glues have their place and use in the shop, I use Titebond for quick and dirty jobs and ones that need to be water resistance. Old Brown Glue when I want longer open time and Hot Hide when I want to either use rub joints or build the piece up in sections with just a few clamps.

Hot Hide glue is great for building up the base units on my work benches. Instead of a forest of clamps for an hour or even a day I only need a few to hold the joint for just minutes after first assembly then reused on the next joint.

ken

[James Pallas]

Chris,

Ingenious and cheaper than my glue pot :). I know some folks say hide glue spoils quickly, that can be true if you do not care for it properly but used correctly spoilage is not a problem. Your way is one way, another is to just turn the glue pot on every day when you walk into the shop. That also takes care of the time needed to get the glue ready to use. If you are not going to use the glue for an extended period you can dry it out by drying on screens then treat the dried hunk of glue just like you would granular hide glue.

Most glues have their place and use in the shop, I use Titebond for quick and dirty jobs and ones that need to be water resistance. Old Brown Glue when I want longer open time and Hot Hide when I want to either use rub joints or build the piece up in sections with just a few clamps.

Hot Hide glue is great for building up the base units on my work benches. Instead of a forest of clamps for an hour or even a day I only need a few to hold the joint for just minutes after first assembly then reused on the next joint.

ken

Here is my set up. Cheap crock pot, candy thermometer jar of appropriate size canning lid for a spacer, to keep jar off the bottom a bit.

[ken hatch]

Here is my set up. Cheap crock pot, candy thermometer jar of appropriate size canning lid for a spacer, to keep jar off the bottom a bit.

Jim,

A good solution, the warming pot doesn't need to be a "traditional" glue pot, anything that will hold the temp will work.

stay safe,

ken

[ken hatch]

It has been a couple of days since I made the demo rub joint so it is time to destroy it. I took the lumpy and a block of wood to the joint and as expected after 3 or 4 hard wacks with the lumpy the wood failed. The joint is still strong. The results would be the same with any modern wood glue so that part is no big deal.

This is with 192 gram strength glue instead of 253 gram strength, I can see no reason to go stronger than 192.

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Another view:

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Click 'em to big 'em, if you do you can see the glue line and the break of the wood.

ken