question about recommended glue

[hazysonic]

I got the recommended PL glue with my omni 10 kit, but it doesn't seem to expand like described in the instructions. I put a healthy bead along the 1" strips that the back will attach to and clamped it-- a small amount seeped out from the pressure, but it did not expand any further as it cured. Is that normal? Are they selling the wrong kind of glue with the kits? I've been told that guerilla glue is a lot stronger, expands like I want, and that the PL glue joints can be easily come apart by hand. Is there any truth to this, and if so why is the PL glue preferred?

[Harley]

I got the recommended PL glue with my omni 10 kit, but it doesn't seem to expand like described in the instructions. I put a healthy bead along the 1" strips that the back will attach to and clamped it-- a small amount seeped out from the pressure, but it did not expand any further as it cured. Is that normal? Are they selling the wrong kind of glue with the kits? I've been told that guerilla glue is a lot stronger, expands like I want, and that the PL glue joints can be easily come apart by hand. Is there any truth to this, and if so why is the PL glue preferred?

If we could could PL glue in this country - I'd use it. But I can't, so Gorrilla Grip Express 1Hr cure is the next best

Leland and Lawrence would not be selling the wrong glue with their kits - so if you got the kit off them, you've got the right stuff.

If you've moistened the joint first ( like the instructions suggest ) and clamp the joint, not so much will ooze out the sides, unless you been excessively generous with the bead. Temperature and humidity also have an affect on the visible expansion. YOu don;t say where you live so I have no way of knowing if temp and humidity are the factors affecting your observation.

Oh....and never listen to what Gorillas tell ya! Try pulling a PL glued joint apart by hand 36hrs after putting it on - and tell us all if you succeed.

[LelandCrooks]

It's the right glue if it came from me or Lawrence. Depends on how much you put in the joint. A nice thin bead will just barely ooze out and expand a little. It expands less than the foamy gorilla glue. I generally have a 1/16 to 1/8 bead to scrape away from the joint. That's also the ticket to make sure you have no leaks, check every joint after curing for ooze out completely along it's length.

I'd say you're being a little sparing with the glue, which is fine as long as you ensure no gaps. It will fill 1/8-3/16 no sweat.

I've used both for these cabs. My very first DR's were with Gorilla, couldn't get PL. Gorilla glue is nowhere in Pl's ballpark. It's a strong, brittle joint. PL is a strong, slightly flexible joint. Gorilla joints break with a snap. PL starts to give at about the same pressure, but still holds for more pressure until it tears the joint apart.

[Bill Fitzmaurice]

PL, and any urethane for that matter, requires moderate temperature and humidity to cure properly. Since we don't know if you're in Yuma or Yellowknife we can't say if your location is part of the problem. But we've got a few thousand cabs out there, not one reported joint failure yet.

[Tim A]

not one reported joint failure yet.

Well, I was playing in this little joint once. They were way out in a tiny town that had 3 joints, all with live music. They had lousy crowds and didn't advertise. Eventually, the joint failed.

Does that count?

[SoundInMotionDJ]

PL, and any urethane for that matter, requires moderate temperature and humidity to cure properly.

+1

I noticed huge differences in the amount of cure time and expansion building in summer and winter.

In summer (>100F, humidity 50-60% during the day), cure time was <8 hours and you could almost watch the glue expand.
In winter (<70F, humidity <20% during the day), cure time was 24+hours, and there was almost no expansion - what squeezed out when I made the joint was about all I got.

--Stan Graves

[Harley]

not one reported joint failure yet.

Well, I was playing in this little joint once. They were way out in a tiny town that had 3 joints, all with live music. They had lousy crowds and didn't advertise. Eventually, the joint failed.

Does that count?

My visit is rubbing off at last I see

[LelandCrooks]

not one reported joint failure yet.

Well, I was playing in this little joint once.

I quit that in high school. You can go to jail for little joints.

[bgavin]

Or wind up divorced for false advertising...

[WB]

I got the recommended PL glue with my omni 10 kit, but it doesn't seem to expand like described in the instructions.

I've been PL'ing the last couple-o-days in 55 degree F. weather and not a whole lot of expanding happening. Cure time is very long as well. That may or may not be your situation.

PL glue joints can be easily come apart by hand. Is there any truth to this,

None.

[hazysonic]

ok that's reassuring. Only thing I'm still confused about--I did NOT moisten the joints b/c the directions on the side of the tube don't say anything about it. I just went down to my garage and double-checked, and the only thing it says to to make sure the surface is clean. So I am supposed to wet the edges? I'm located in Dayton Ohio--somewhat humid lately.

Here's their product description, so you can see what I'm reading:
http://www.stickwithpl.com/Products.asp ... 43f2ef9458

[David Carter]

ok that's reassuring. Only thing I'm still confused about--I did NOT moisten the joints b/c the directions on the side of the tube don't say anything about it. I just went down to my garage and double-checked, and the only thing it says to to make sure the surface is clean. So I am supposed to wet the edges? I'm located in Dayton Ohio--somewhat humid lately.

Here's their product description, so you can see what I'm reading:
http://www.stickwithpl.com/Products.asp ... 43f2ef9458

I've built 5 BFM cabs now, and each has been built with PL Premium. Temperatures have varied from low 40's to 90's. I have never moistened anything, and I have always had great results. As previously mentioned, expansion and cure time will vary based on temp and humidity, but, in the end, you'll always end up with a joint that is strong enough that you'll break the wood next to the joint before the joint itself will come undone.

In other words, don't sweat it--you'll be fine. Put down enough to get a little squeeze out along the entire length of the joint. Don't try to wipe away the squeeze out right away. Let it dry, and then scrape away with a chisel, utility knife, or some other sharp instrument.

[Harley]

ok that's reassuring. Only thing I'm still confused about--I did NOT moisten the joints b/c the directions on the side of the tube don't say anything about it.

OK, then the PL brand does not mention this, but this does surprise me that they doon't

With 100% expanding polyurethanes, damp ( not saturated ) joints will help the expanding glue penetrate more easily and thoroughly into the pores and create a stronger joint. Most of the EP type glue manufacturers allude to this. Thus it makes it good practice, especially in very dry or hot climates.

[AntonZ]

FWIW - notice the difference between damp and dripping wet. Damp is good, wet is not good. PL (and other PU based glues) depend on a little water being present for curing, it acts as the second component, so this is actually 2-component glue from a single tube. Presence of some water is good, but you don't make the wood dripping wet.

In very dry weather, I slide a moistened rag along the sides of the plywood that I'm about to put together, some 15 minutes before actually gluing them together. If it's not very dry, I don't bother and the amount of water that is naturally present in the air at higher temperatures is enough for the glue to cure.

[LelandCrooks]

In very dry weather, I slide a moistened rag along the sides of the plywood that I'm about to put together, some 15 minutes before actually gluing them together. If it's not very dry, I don't bother and the amount of water that is naturally present in the air at higher temperatures is enough for the glue to cure.

In very dry weather an open beer in the shop provides enough moisture for you and the glue.