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So I need some tips or advice on plate joint with Hot Hide Glue. I’ve gotten into plate joining with HHG and been using the tape trick where you tape plates together at angle add the glue then close them. My problem is the squeeze out. The joint glues fine this way but while gluing braces and stuff with HHG it’s a more stable operation due to clamping and go bars and such so scrapping the squeeze out off after it gets rubbery is no big deal. With the tape method of plate joining you have a front side and back side to contend with plus I’m scared to move the plate around much until it’s set overnight. Am I being to cautious and causing myself an unnecessary sanding job?

I’ve thought putting beeswax on top and backside of the joint and cleaning with naphtha before sanding and finishing, but not sure if this is asking for trouble. I’ve been mixing my glue @ 1:1.8 but I think it might help to be a little thicker. I do know I like squirting it from a small bottle better than brushing it. Sorry to be so long winded Any advice is appreciated and thanks.

Get off what you can while it's rubbery and wipe the remaining glue off with a damp cloth of hot water. I wouldn't bother waxing or anything. You are thicknessing the plates after you join them aren't you? In which case you'll sand or plane off any remaining squeeze out.
You glue mix sounds about right to me. Also I've had better luck brushing the glue on than dispensing it from a bottle. It cleans up so easily even after it's dry that I don't worry too much about making a mess.

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Jim Watts
http://jameswattsguitars.com

I've had great success with this method and as Jim said, you're going to sand or plane it anyway so squeeze out is a non-issue. I've never used a clamp of any kind and the joints are about impossible to find on spruce.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Guess I’m scared of moving the plates around to do much cleaning before it starts to get hard. How long do you let yours set before after glue before moving? Yes I glue before final thicknesses is reached.

I use the tape method with HHG too. I don't really worry about the squeeze out too much since I am just going to thickness after the glue dries. When I push the plates down and tape the second side, I wipe up what squeeze out I can and let the glue in the joint gel for a bit, then I wipe off whatever I can easily on the back side. By that time the joint isn't going anywhere. I just prop it up against the wall out of the way and let it dry.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I stretch the tape across the joint on the "down" side first, then run a strip of tape along the length of the joint on that side, flip the top over, "tent" the halves, run a bead of glue along the open seam, lay it flat and stretch tape on the "up" side. The tape run along the seam on the down side reduces the amount of glue that squeezes out on that side. After the glue gets rubbery I scrape off the most of the squeeze out on the "up" side with a chisel, put spring clamps on the top and bottom edge at the seam and hang it in a humidity controlled closet. I usually do a number of tops at the same time.
I don't spend much time doing clean up while doing glue up - a single swipe with the chisel to remove some squeeze out. Better to not disturb the joint too much at that critical time. Scraping and final thicknessing after the glue has fully set I think is the better way to go.

It's best to do the joining before you thickness the plates. For one thing, it's hard to get them to come out perfectly level across the joint, and you tend to lose a bit of thickness no matter what. Since hid glue draws in well you don't need a lot of clamping force per square inch, so it doesn't hurt to leave extra thickness. Allow at least 8-10 hours after gluing, and preferably longer, before you work the plates. This not only allows the glue to fully set up, but also give time for all the moisture to get out of the wood. Rushing it can leave a sunken line along the joint later. DAMHIKT

I've seen the sunken glue line from thicknessing too soon. I have the luxury of not being rushed so I let the plates sit a week or so while I prepare other parts of the build. I don't know how long is long enough. I'm probably waiting longer than needed, but for me it is easy to join the plates when I start a project and make the rim and stuff before I need to worry about bracing the top and back.

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

The center seams of the top and back are places where I would rather it stay messy until fully dry, and then just sand it all flush in the drum sander. That's not the case for other hot hide glue operations; for most joints, I would much rather clean up as much as possible after the clamps (or go bars or whatever) are in place. But the center seams are a special case.

I don't have any trouble with fully dried hide glue gumming up my drum sander sandpaper. Even if I did, I would consider the ease of this method as worth the expense.

Yeah thanks guys lots of good info. One thing I do battle is timing my free time to do these things with good weather because my shop is not climate controlled so I normally try to do the gluing in the morning and bring them in several ours later to the house to minimize issues.

I once had some HHG stacked heel sections glued up and forgotten them curing for a few days in the shop and some mold started in on them at the squeeze out, it sanded off no big deal but sort of scared me at first. Glue was only a week old and had been stored in the fridge. I did use some wax paper so maybe that contributed to moisture but anyways.

I am the drum sander

I have developed a system where I can join the plates even when they are at their target thickness. I had to do this because I have a whole bunch of Imbuia floor boards and when resawn they come to about .9in finish sanded. It's not that hard to do really. I just have two pieced of MDF that is very slightly curved on the bottom so that when it is clamped down it pushes from the center to the edge. then I use a wedge system to clamp the plates.

My point being that I even do this when joining plates that are plenty thick because it's nice to have everything level. Then a simple cabinet scraper will very easily remove any dry squeeze out. On the underside is a piece of craft or newspaper which also will soak up a bit of squeeze out and is easy to scrape off.

It also helps to get the right amount of glue on this joint too. It really doesn't take much. That's something I have fine tuned over the years as I used to think I had to gob glue on everything.

Yep. Glue up a test piece and wait until the glue gels but is still wet enough that it peels off easily. Take all the tape off and see how much force it takes to get the joint apart


I've had that happen before too, with this and other joints. Mostly it's a matter of the tape or clamping cauls preventing the surface from drying out, so the trick is to start your waiting timer when you remove the clamps rather than when you put them on It should be fine overnight then.

Yep. Glue up a test piece and wait until the glue gels but is still wet enough that it peels off easily. Take all the tape off and see how much force it takes to get the joint apart

I take this as you saying I maybe surprised as to how stable the joint is even when squeeze out is still slightly rubbery / removable. I probably am being over cautious but this type of application and method for HHG is relatively new to me. I probably just need to relax and enjoy the process more but HHG as wonderful as it’s is induces stress sometimes

Well, that job stinks!

If you don't have a drum sander, let me amend my advice slightly. You might want to invest in a serious glue scraper, like this one:

https://www.stewmac.com/luthier-tools-a ... FoEALw_wcB

It doesn't have to be the Woodpecker/StewMac scraper; just some sort of unyielding, pull-stroke scraper.

I still think it is worthwhile to just let the center seams stay messy until they are fully dry; but scraping fully dried hide glue is real work. Card scrapers can do the job, but something stiffer would make the job go easier.

When I used the tape method with HHG I only had tape on one side of the top. I'd run a bead of glue, push the halves down tape side down on some foil or wax paper, and put some small weights (like 5 lb plates or something) along the joint on both sides to keep things flat. Once it gelled I'd run down the joint with my [LMI] glue clearing chisel to scrape off the squeeze out boogers. That was all.

Hide squeeze-out on plates cleans off with a plastic 3" putty knife as soon as the 'tent poles' are removed and the joint is closed...tape or wedge after that (we did both) and count on sanding or planing to take the final bit of residue off.

_________________
For the times they are a changin'

- Bob Dylan

Another way to align things when the plates are near the target thickness is to combine the tape method with go bars to hold the seam flat.
I also like to let the back seam dry for a week before gluing on the back graft to avoid sunken seams.

Read Alan's advice again:)

Most likely. But either way, feeling it with your own hands is more meaningful than anything that can be conveyed in words. And the experiment only takes a few minutes to perform.

Does fish glue act similarly, besides the setup time?
What about multipiece tops and backs? Each joint separately? What about full thicknessed backstrips?
Sorry for all the questions, just trying to make the next ones easier/better.

I've never used fish glue, so I can't speak to that.
If I am just gluing small "wings" on a top and I have the thickness (3/16th inch) I normally do glue ups at I will do a rub joint for the wings, let them set up some and then do the tape method for the center seam. I haven't found the need to do more than adding small wings to the lower bout. We modern builders have the luxury of buying good quality if not cosmetically perfect tops for a low price. Alaska Specialty Woods lists A grade Classical sized Sitka soundboards for as little as $8. If you are willing to glue wings on them you can build bigger guitars from many of them.
In the past for gluing up multipiece harp soundboards I've used the tape method with weights to hold the sections flat against a piece of MCP (with a piece of wax paper between the MCP and spruce) Harps run the grain crosswise to the length of the soundbox so the joints are comparatively short.
For full depth center strips the tape and go-bar method works, but you will want to put more go bars on either side of the joint and a non stick (cello-taped) batten between the center strip and go-bars, running the length of the center strip and extending slightly over both sides of the back joint. The batten needs to be stiff enough to hold the strip flat between the go-bars. I use titebond for these types of "sandwiched" glueups because of the extended open time.
I'm sure others can tell you other (and possibly better) ways to do the same things, which I also look forward to learning.

I always have difficulty navigating Alaska specialty woods site. I never can see the the items listed that are in stock for sale. Maybe it’s my device or maybe it’s the nut behind the wheel.

Been tying plates together since I can remember. Works well with HHG. As stated, HHG cleanup is a non-issue once dried and thickness sanded.

Slim, It is supposed to be made to be easy to navigate. I liked the old category system, But my webmaster thought the filter system like big online stores use, such as home depot and others, is cleaner and faster.
I'm only a phone call away. I can help you navigate to exactly whatever you are looking for. I'll get on my computer and you can be on yours. Just make sure to call during our business hours, 8am-5pm local Alaska time .