PL vs. wood glue

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himhimself
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PL vs. wood glue

#1 Post by himhimself »

I've become a huge fan of PL, using it for lots of other types of projects around the house too. However, I have a question. Is there any downside to using a good wood glue for some of the face to face joints? For instance, the woofer spacer to baffle (assuming no mesh), or some of the places specifying to double up 1/4" ply to give 1/2" thickness. PLs great, but the mess is sometimes annoying.
2xT30 (20", 3012LF)
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Bruce Weldy
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Re: PL vs. wood glue

#2 Post by Bruce Weldy »

himhimself wrote: Mon Aug 20, 2018 2:16 pm I've become a huge fan of PL, using it for lots of other types of projects around the house too. However, I have a question. Is there any downside to using a good wood glue for some of the face to face joints? For instance, the woofer spacer to baffle (assuming no mesh), or some of the places specifying to double up 1/4" ply to give 1/2" thickness. PLs great, but the mess is sometimes annoying.
If the woofer is sitting on top of the spacer, then yes it has to be airtight and you should use PL. If you just mean the blocks behind the baffle in some designs for holding the driver screws, then no.

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jimbo7
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Re: PL vs. wood glue

#3 Post by jimbo7 »

himhimself wrote: Mon Aug 20, 2018 2:16 pmPLs great, but the mess is sometimes annoying.
PL is like making love. You get better at it over time.
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Bruce Weldy
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Re: PL vs. wood glue

#4 Post by Bruce Weldy »

jimbo7 wrote: Tue Aug 21, 2018 6:58 pm
himhimself wrote: Mon Aug 20, 2018 2:16 pmPLs great, but the mess is sometimes annoying.
PL is like making love. You get better at it over time.
And get some surgical gloves.....it's worth the small expense....

6 - T39 3012LF
4 - OT12 2512
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"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

CoronaOperator
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Re: PL vs. wood glue

#5 Post by CoronaOperator »

And don't wipe it, you will make a bigger mess. Let it set up for ~4 hours (temp, humidity depending) until it is not tacky any more but still very pliable and then tool it.

I use these cheap artist tools from Michaels:
Image

Let it set for 4-5 hours, too long and it will get too hard, too soon and it is still messy:
Image

Then it will tool very easy, finished result:
Image

After a bit of practice you can get the joints looking perfect even with 1/8" gaps in the wood. I don't even remotely try to make my cuts perfect anymore, not worth the effort.
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James Champer
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Re: PL vs. wood glue

#6 Post by James Champer »

It is easier after just a couple of hours but.. If you have sharp chisels, and I mean sharp, it doesn't matter when you decide to trim the squeeze out. I've even waited several days.

And let's be real here, every wood chisel should be sharp :)

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Bruce Weldy
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Re: PL vs. wood glue

#7 Post by Bruce Weldy »

I usually wait an hour or two, then run a utility knife down one panel then the other. Leaves a nice corner and the piece of PL just falls away.

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Rune Bivrin
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Re: PL vs. wood glue

#8 Post by Rune Bivrin »

himhimself wrote: Mon Aug 20, 2018 2:16 pm I've become a huge fan of PL, using it for lots of other types of projects around the house too. However, I have a question. Is there any downside to using a good wood glue for some of the face to face joints? For instance, the woofer spacer to baffle (assuming no mesh), or some of the places specifying to double up 1/4" ply to give 1/2" thickness. PLs great, but the mess is sometimes annoying.
For that particular application I have no doubts about using regular wood glue. Just cover the surfaces completely. Not getting that air tight is almost a feat. I used regular wood glue for the doubling up of 1/4" in my DR 250-s. The expansion of PL would have been more of a problem than a blessing there, I think.

For braces and panel joints, PL Premium (or something equivalent) is absolutely advised. It's not just about being air tight, it's also about not having voids that can vibrate and cause noise.
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