Public service announcement...

[philthien]

When gluing-up mitered MDF enclosures, don't forget to apply glue to the extreme ends, otherwise you'll have one corner w/o any glue.

Good thing I caught that in time.

Any longer and it would have been a problem because the front and rear baffles are inset and glued into grooves. The glue hadn't set-up so I was able to tap it back apart and squeeze some glue into the joint.

I guess this is a good reason to use the original Elmer's white glue, which has a longer open time than the Titebond stuff.

[Paul K.]

Have you tried Titebond II Extend? It has a longer open time. It isn't carried at either Home Depot or Lowes, where I get most of my woodworking supplies and materials, but it is at Woodcraft.
Paul

When gluing-up mitered MDF enclosures, don't forget to apply glue to the extreme ends, otherwise you'll have one corner w/o any glue.

Good thing I caught that in time.

Any longer and it would have been a problem because the front and rear baffles are inset and glued into grooves. The glue hadn't set-up so I was able to tap it back apart and squeeze some glue into the joint.

I guess this is a good reason to use the original Elmer's white glue, which has a longer open time than the Titebond stuff.

[philthien]

Have you tried Titebond II Extend? It has a longer open time. It isn't carried at either Home Depot or Lowes, where I get most of my woodworking supplies and materials, but it is at Woodcraft.
Paul

I haven't tried it, mostly because the Elmer's Glue-All has an open time about 2x the Titebond II Extend:

https://www.wwgoa.com/article/measur...assembly-time/

...and I don't need "weatherproof" glue because none of my speaker projects (at least so far) have been intended to use anywhere but inside.

I guess I will have to remember it if I do decide to build something that may see outdoors use, though, because the Elmer's absolutely isn't an outdoor glue at all.

I should probably have some of the II/Extend on-hand for making things like cutting boards, etc., as well (I don't always build speakers).

When I was just a kid and taking shop class, the shop teacher (who is a woodworking artist, the stuff he made was always absolutely hilariously stunning and I don't know what he was doing teaching a bunch of 6th thru 8th graders other than getting free shop-time between classes) always used the Elmer's Glue-All for everything, including his own projects.

That is why I still use it, I suppose, I'm trying to channel my old shop teacher.

[Gordy]

Take a look at Titebond 3. It has a 8-10 min open time and is FDA approved for Items like cutting boards. You can also find it at the big box stores. I use TB3 for a lot of stuff an TB2 when I am mocking up a design and need a quicker set.

[badman]

When using MDF, it's good to feed the edge before glue-up. Basically, lightly coat the edge of the MDF with glue until it stops sucking it up, then add a little more glue for bonding and clamp up. This not only prevents the mdf from sucking up all the glue and creating dry spots, but strengthens the MDF itself and helps prevent moisture pickup.

[skatz]

[QUOTE=philthien;n1400280]
https://www.wwgoa.com/article/measur...assembly-time/


Interesting, thanks.

[philthien]

When using MDF, it's good to feed the edge before glue-up. Basically, lightly coat the edge of the MDF with glue until it stops sucking it up, then add a little more glue for bonding and clamp up. This not only prevents the mdf from sucking up all the glue and creating dry spots, but strengthens the MDF itself and helps prevent moisture pickup.

I use glue to treat edges that will be receiving paint, but I haven't allowed glue to soak into MDF before applying a 2nd coat.

That is a good idea that will give me the maximum open time, so I'm going to use it next time, thanks!

(I leave my stuff in clamps overnight, I'm not a production shop. I'd rather have longer open times than faster setting time.)