Large mitered carcass glue up - bad to do in stages?

[Sean Moore]

Im getting ready to glue up a large mitered carcass, and im wondering if there is any disadvantage to do a large glue up like this in stages? Rather than use slow setting epoxy and try getting all 4 sides clamped together at once, is there any major disadvantage to glueing each corner up seperately and letting it full cure before moving on to the next?

Ive always used epoxy in the past for this sort of thing but I generally dont like the clean up of epoxy. I find that even if I tape the joints it still leaves a noticeable line that is hard to sand out.

[Andrew Hughes]

I would glue up the whole carcass it’s the only way to get it symmetrical. Measure inside corners.
Resist the temptation to rely on square corners.
Why would you need epoxy is it really that complicated. Tite bond has good open time in the winter
Good Luck

[Michael Burnside]

Done it both ways. Last project I broke it up because the piece was 78” wide and had a floating box in the middle. I just use Titebond II most of the time.

[Scott Winners]

I would glue up the whole carcass it’s the only way to get it symmetrical. Measure inside corners.
Resist the temptation to rely on square corners.


What Andrew said.

[andy bessette]

I use WEST epoxy exclusively to glue up large complicated assemblies. Just be meticulous with your cleanup before it cures.

https://i.postimg.cc/h4YPrTSM/surf-3.jpg (https://postimages.org/)

[Mark Gibney]

I hear you with the distinctive line that epoxy can leave. No matter how well you clean up the squeeze out it can still leave a darkened shadow somehow.
I find Gorilla glue leaves less evidence at the scene of the crime, and any discoloration is easier to sand out.
Titebond III?

[Mike Cutler]

Glue it up as a single process. Fighting to get a large carcass square in sections and stages will be challenging. Unless the design requires that and it has been preassembled and goes together square with light clamping. If it has to be pulled into square, that will be really challenging
If you're getting a lot of squeeze out with epoxy, use less, and possibly consider going to a structural epoxy, ie T-88, that really only requires contact with the two pieces. There really shouldn't be a lot of squeeze out, unless you're laying up a bent lamination. Keep a rag on hand and a can of acetone to lightly clean up any squeeze out that does occur, just don't scrub the acetone into the actual joint itself.
Andy is very much correct to clean it as you go. 30 minutes spent cleaning up while it's still in a liquid form, is a lot easier than a couple of hours scraping and sanding down after it hardens. ;)
I have found that West epoxies to be less inclined to make the dark line, than the System 3 epoxies. I think it's because the hardner for the west system is clear, whereas the hardner for System 3 is amber. Regardless, you have to clean that joint up of any "dust", or the epoxy will react with it and become tinted.

[Kevin Jenness]

Best to assemble all the parts at once to keep the assembly symmetrical and square, but as long as the joinery allows for it you can apply glue to only the joints you choose, then glue the others after the initial cure. Titebond Extend, slightly diluted yellow glue, plastic resin or liquid hide glue can give you more assembly time as well. I usually use epoxy for complicated assemblies but there is no denying that it tends to leave a visible glueline due to end grain saturation. A trial glueup will ensure that all the clamps and cauls are at hand and may give you the confidence to complete the whole sequence at one go.

[Brian Tymchak]

A trial glueup will ensure that all the clamps and cauls are at hand and may give you the confidence to complete the whole sequence at one go.

I also would do the glue up in one go to assure squareness. It will build in stress to the carcass if you have a cured joint out of square and have to flex something to make the next joint fit. As Kevin says, do at least one dry run. I've practiced a few glue ups several times to make sure I wasn't missing something and to smooth out the process.

[Michael Schuch]

I have found that lock miters instead of regular miters can make glue ups a lot easier. I also use Titebond III.