Glue open time

Re: Glue open time

Glenn Madsen near San Francisco

>I've had reasonable success with the Titebond Extend series of glues. The Extend original (not particularly waterproof) is what I've used. Plenty strong for my purposes, but check their website for your own application.

Your dovetails should give you plenty of joint strength anyhow, I'd think/

thin to increase time

bill tindall, E. TN.

>Yellow glue can be thinned with 5% water to increase open time and decrease viscosity. There is no loss in ultimate strength but the joint needs to be clamped longer. I use a scale to get this dilution right. Yellow glue is a non-newtonian fluid so a 5% dilution will have a vastly larger decrease in viscosity than 5%. Don't over do this dilution.

I get a helper for these jobs. Also, partially set yellow glue has low shear strength but high impact strength. So, while you might not be able to beat a joint together one can always coax a joint together with clamp pressure. These clamps need to be at the ready in case they are needed. You don't need to be adjusting clamps and finding pads if the joint hangs.

Try Lee Valley GF2002

Neal in San Jose

>Or is it 2002GF? Anyway I've had good luck with it. It has about twice the open time of yellow glue, and the added benefit of being gap filling. It is just about the only glue I use anymore and glue-ups aren't nearly as stressful! I haven't tried thinning it as suggested above, but so far I haven't needed to.

Also, a dry run is a very good idea. Do everything you would normally do, including placing all the clamps. Nothing ruins your day like discovring a baulky clamp in the middle of the glue-up-dance.

Cool temp

Jim in Burlington On

>If you can do it where it's a little cooler with GF 2002 glue. I have used a spatual alla Rob Cosman. If you have a small squeeze bottle to put it on a brush or spatula it will go alot quicker.

Re: Glue open time

Bruce, a MN Galoot

>On SMC, one guy put together the dovetailed box for a tool chest using epoxy, partly for the open time. My tool chest didn't use the dovetailed approach, but I used liquid hide glue and was really pleased with the result.

Bruce

I was just thinkin;...

Bruce, a MN Galoot

>that you could also modify your glue-up procedure. Just glue half at a time and rather than gluing the second half on, just assemble it but don't glue and use it as a gluing jig. Take the unglued side off when the first one has set and glue the second.

If that makes sense...

Bruce

I do this a lot myself...

Scott Burr in Ben Lomond, CA

>Water it down a bit, use a brush to apply and then go to town with the clamps.

Good Plan

David Charlesworth

>This strategy, gluing in two stages was being recommended by Robert Ingham, to his students at Parnham House, on the day that I visited.

Anything that makes glue ups easier and simpler is a good idea.

Full dress rehearsal, "dry glue up", is essential. Its no good finding you lent those essential clamps to your neighbour when the glue is going off!

We put neat glue in the sockets, with spatula or thin shim spreader, and paint 5% dilute glue very thinnly on 2/3rds of the pins. This ensures wetting of both halves, and gets most of the squeeze out moving to the exterior.

Glue failure is most often caused by failure to wet both surfaces, (Hoadley).

That old wives tale about dovetails only fitting once is for experts only.

David Charlesworth

Re: Glue open time

John M

>Mark

Give Old Brown Glue a try. It's a liquid hide glue that will give you about one hour to assemble. I first learned about it from Brian Boggs..he uses it on almost all the chairs he makes.

John

gluing by halfs pitfalls

bill tindall, E. TN.

>While this seems like a sound strategy, it can fail. When I have tried gluing up things to be square in two sections, the final assemble didn't always mate up. Admittedly, this was a failure on my part to get the two sections cut and glued up perfect, and lack of perfection is a reoccurring problem in my shop. Hence, I use strategies that don't require perfection when possible, ie gluing up assemblies in one session.

Re: gluing by halfs pitfalls

Bruce, a MN Galoot

>"lack of perfection is a reoccurring problem in my shop"

Heck, Bill, I thought I was the only practitioner of this problem. Must be something in the air.

When I glue up in halves, I use squaring jigs to hold things in position. While this has the potential to fail, like everything else, so far it has worked fairly well. But then I've done that mostly with small things like drawers and boxes, no carcase work.

Bruce

Gluing a dovetailed chest

Warren in Lancaster, PA

>I used to make dovetailed blanket chests on a regular basis for a dealer. I used hot hide glue so I had to have a smooth operation. Here are some suggestions. Make sure that the parts mate well- you don't want to be chiseling while the glue dries. Mark the parts and lay them out so you know where each part is and how it is oriented. Assemble all the tools you need like clamps or mallets and have them ready to go. Put the glue in an open container and use a brush that can hold plenty of glue so you are not constantly dipping. Put glue on a front corner, assemble, do another corner and assemble, then do the back all at once.

For more complicated assemblies it is nice to have a helper spreading glue. Even a six year old can help spread glue.

Question

Dan Donaldson

>Why would you prefer not to go the hide glue route? Hot glue is probably a bit too fast, but the liquid stuff has a good open time. I use it almost exclusively except where I need water resistance.

Re: gluing by halfs pitfalls

David Charlesworth

>Bill,

Don't really understand.

For a rectangular carcass one side is glued. The opposite side is in situ, assembled but dry. Squaring using diagonal stick is the same as usual.

I am not seeing how this plan would make squaring of final glue up more difficult?

David

now I see.....

bill tindall, E. TN.

>I missed the detail of assembling the whole unit in round one, just not gluing half the joints. (I need to read more carefully) Seems that even I might make that work. On the other hand I have a wife that is experienced in glue slathering, and that cuts by half this operation.

now that is sage advice

bill tindall, E. TN.

>

Re: now I see.....

David Charlesworth

>An assistant is great!

David

Great helper there...

vlparisian - Houston

>My bride would want to be treated to dinner in exchange for the help :>)

Oh, and if the phone rang halfway through the glue up....

Re: Great helper there...

Bruce, a MN Galoot

>Over the years my wife has gotten to be pretty good at glue-up time. However, when we first started it took a total revamping of both my expectations and procedures. She was willing to help, but she didn't like me to tell her what to do (still doesn't, even though she doesn't know what SHE's doing). And since she didn't know what she was doing or more importantly what I was doing, she would ask questions. In the middle of the glue-up.

Well, that didn't work very well. So after a few years I finally got smart and started to explain the whole process before we started a glue-up - clamp placement, spreading the glue, cauls, etc. Then I added the caveat that she wasn't allowed to ask questions during... That helped.

Bruce

Patrick Edwards' Old Brown Glue

Greg B�tit, Vergennes VT

>Is that what you mean? It's hide glue that comes in liquid form & has something in it that gives it lots of open time. Joel sells it. Nothing cleans up like hide glue, so I have started using it for chair assembly.

Assembling the chair undercarriage, especially the way I do it, requires a lot of open time. Basically you fit the legs into the seat holes, and measure for the stretcher lengths. Measure the angle and glue up the stretcher "H". Then, one at a time you measure the proper angle for the holes in the legs for the stretchers, glue and assemble the joint and repeat three more times. Then you glue up the leg/seat joints all at once. The wet joints are able to move all through this process to accomodate the next joint, so that all 10 undercarriage joints are as happy as they can be when the glue dries. That takes about as much time as a particularly fussy dovetailed carcase glue up I would think. (This is the technique taught by The Windsor Institute- they recommend using white glue (like the Elmer's stuff you used in Kindergarten) because it has a longer open time than yellow glue. It actually is a pretty good wood glue, it would certainly hold dovetail joints as well as they needed to be held.)

greg

Take the phone off the hook!

David Charlesworth

>I would sooner ask a passer by than my beloved. She does not seem to understand the stress levels, and doesn't appreciate the snappy orders/requests which this stress induces.

Another important strategy, take the phone off the hook before starting.

David

Re: Patrick Edwards' Old Brown Glue

Pam Niedermayer - Austin, TX

>You've lost me, Greg. Are you saying that at glue up time you're just cutting the mortises for the stretchers?

PAM

Re: Patrick Edwards' Old Brown Glue

Greg B�tit, Vergennes VT

>Sorry Pam,

I re-read that & don't doubt that you're confused.

Yes, the holes for the stretchers in the legs are drilled and glued one at a time in sequence. I'd guess the time from when the sreatcher "H" is glued until the 4 leg/seat joints are assembled is at least a half an hour. I don't know for sure the duration, so I tried to describe all the steps that are in between the first and last joint glue-up to give you the idea how long the glue stays open.

greg

You forgot one thing...

Scott Burr in Ben Lomond CA

>Go to the bathroom before starting too.