Minimum clamp time after glue up??

[Random Orbital Bob]

Hi Guys

Simple question this...I use a ton of pva on my internal projects as Im sure many of us do. Now I appreciate any serious glue ups take 24 hours to really cook but how "short" would you leave clamped white glue to go off ie whats the minimum clamp time you could get away with without seriously risking the joint failing?

I will take small sub assemblies out of clamps from an am to pm type time....3 to 4 hours but intuitively I'm loathe to take stuff out before that kind of length. Am I being over sensitive ie is an hour good enough?.....less?

Whats your collective take on this. I've been doing it for yonks and dont really know the right answer. One point to make...Ive not had a joint fail yet using the conservative approach...but it can really slow the project down.

 

[Chrispy]

It really depends what you are gluing, tight fitting m&t or dowel joint with good shoulders on a warm day 5 minutes would be ok, but badly fitting butt joint on an oak table top, over night at least!

 

[No skills]

I have a tiny bit of experience of glueing up compared to you pro's but I have found a large difference in setting time (or at least workable strength) when doing stuff on very humid days v dry(er) days, double the time in fact.

JME

 

[No skills]

As an aside I've started using joiners mate for things I want stuck quickly but without the maximum strength of pva.

 

[Phil Pascoe]

I have a tiny bit of experience of glueing up compared to you pro's but I have found a large difference in setting time (or at least workable strength) when doing stuff on very humid days v dry(er) days, double the time in fact.

JME

If I glue up in the summer and I want a few extra minutes, I lightly spray the joints with water first to slow the grab/drying time down a little.

 

[No skills]

Thats a handy one, will have to try it.

 

[Dangermouse]

This is really a thing you learn with time. A bit of intuition and guesswork. Every job is different and you just cant say when any glued joint will be set until it is .

 

[Random Orbital Bob]

I appreciate that Dangermouse.....Ive been making things out of wood for over 30 years myself. The purpose was to see if my experience matched other peoples...out of curiosity really...to see if maybe I was missing something.

The variations in method that relate to ambient temperature are interesting.

 

[Melinda_dd]

At work veneered mdf to veneered mdf..... 35-45 mins ...... hard wood to mdf around an hour. .... hardwood to hardwood a couple of hours if poss.... at least an hr and a half

 

[rdesign]

yellow glue 30mins in a warm workshop 12 + degrees

 

[Random Orbital Bob]

Thanks to all