joint strength

[BumoutBob]

Jim answered my question quite well, thanks.

 

[Don Sorensen]

All those "I don't see glue wearing out over time" - I have trouble believing that with the experiences we've had with our dining room chairs. Several of them have loose joints because the glue is gone? Not sticking?.

Granted - it's probably made from pine.
Granted - it's probably not the best joinery available
Granted - they're put under a great deal of stress on a daily basis sliding our large carcasses around :gar-La;

But part of the reconstruction was having those joints re-glued.
Just my $0.02 but I've a lot of free time today and had to speak up.

 

[charlie s]

Howard:

I've heard of benefits from using plastic resin glue on table top glueups to avoid "creep". What is your opinion of this? I did experience some creep on a table top I did using pva and wonder if I could have avoided it with plastic resin glue.

Charlie

 

[Howard Acheson]

>> I've heard of benefits from using plastic resin glue on table top glueups to avoid "creep". What is your opinion of this?

That's what I have used for 15 or more years. PVA is perfect for many joints but urea formaldehyde (Plastic Resin) is the best for panels and bent laminations.

In the shop I was involved with, we stopped using PVA for panels in the mid 1980's. We had too many call backs.

 

[Joe Scharle]

>> I've heard of benefits from using plastic resin glue on table top glueups to avoid "creep". What is your opinion of this?

That's what I have used for 15 or more years. PVA is perfect for many joints but urea formaldehyde (Plastic Resin) is the best for panels and bent laminations.

In the shop I was involved with, we stopped using PVA for panels in the mid 1980's. We had too many call backs.

What's your favorite brand, Howie?
Joe

 

[Travis Porter]

You can't "reglue" PVA without totally cleaning and sanding all parts. If all parts were sanded then your joints would be loose.

IMO, for chairs, a combination of woods of varying moisture content is needed or joints that are pinned and/or locked especially on the legs and runners. The only adhesive I know of that can be reglued, ie will bond to itself is epoxy.

 

[JimD]

The 4 kitchen chairs I made are only a couple years old but are holding up fine and were glued with PVA. It is also all I have used for panels and I have not had any issues on muliple smaller tables (end, coffee, hall) and raised panels. The chairs are red oak with about 30 mortise and tenon joints per chair. They get used daily.

I can't see how PVA would creep on a table top. If it was constantly loaded it might shift but a table top should not see any siginficant loading. I can see using something else due to the rapid setup of PVA, however. I sometimes limit the number of boards I glueup at one time because it's hard to get them all in position before the glue starts to setup. If I saw a bad glue joint, I would worry I was moving stuff after the glue was partially set.

Jim