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[Gary Perrett]

+1...on the glue and double so the gloves.. that stuff is MURDER to get off!
G

[Too Tall (Curtis H. List)]

peter.golde wrote on Sun, 19 October 2008 19:47

I used West System epoxy for my first batch of Labs, more work than it was worth and is very expensive. I agree for perfect joints tightbond is best. All of my speaker projects since the Labs with epoxy have been glued with PL Premium 100% polyurethane. All my boxes suffer the worst kinds abuses including falling out of a truck on the highway, and none have failed, no leaks, no joint failures. PL is nice because it gives a first time builder enough time to unscrew and pull apart and redo mistakes, tightbond doesn't afford this luxury. PL with screws and clamps, the extra will squeeze out and imperfections will be sealed. If you don't have to rebuild wood with epoxy, PL is the best choice. Use a pair of rubber gloves to avoid getting it on your skin.

I can see where West System is a lot more expensive then Titebond woodworker glue. I thought that The PL would cost near as much.

Also for the west system did you use one of their "fillers"?

For using it as a glue you should use quite a bit of filler. This will give the epoxy some "body" and it should stretch the epoxy so you do not use as much to build a box.

The only time you use straight expoxy is if you are using the epoxy as "Paint" over the entire surface of the box to protect it from rain, etc.

Note that UV light will break down the epoxy. They have an additive if you use it for the top coat.

My main beef about using any PL product is it takes up room. You have to clamp the crap out of a joint to move all the excess out as it should be. The joint should not be starved, but the joint should still be touching everywhere, not held apart by 1/32".

We are back to wood glue again.

If the joints are properly milled PL is not a good idea since it will take up too much room. Both wood glue and expoy will easily be squeezed out.

For poorly milled joints or places where it is difficult to get in clamps or use screws as clamps PL is a good solution. I just think expoxy with the correct filler is somewhat better.

I agree that being able to move things a while after the box was built can come in very handy. Especially for a woodworking novice (Or a professional that fucked up).

They have worked on wood glue (Like Titebond) till it starts to bond in a few minutes. Within less then 60 seconds the only way to move things is with pipe clamps.

Once epoxy starts to kick off not even a sledgehammer will move it.
The only thing worse is contact cement.

Lastly, as you mentioned getting PL on your skin is a fairly permanent situation. If you look on the tube it may tell you what works (gasoline?, Mineral spirits?, Just guessing)

Many epoxy brands are very hard on you skin (rashes) and your lungs (when they kick off).

West System has a reputation for being kind to your skin for most people. I have never had a reaction.

Also the only time the vapors it makes when it kick off have bothered me is when a pot "gets away from you". When it kicks off so fast it makes smoke I try not to breath it. Otherwise it does not bother me.
As with all things to do with single person's allergies YMMV.

[Jeff Bailie]

I have to again agree with Curtis on the West Systems. It took a few tries to get my mix right. I now think the proper West system mix for most of the joinery I had to tackle would be: 105 Epoxy, 206 SLOW Hardener, And 406 filler.  I tried 407 and 405 fillers and did not get the creamy mayonnaise consistancey I wanted. I believe 406 filler is best for Baltic Birch. I would also stay away from the 205 FAST Hardener, until you have used West systems for a while. It can get very hot very fast.

[Jeff Bailie]

Just have to get them coated and they will be ready for battle.
I have used them twice now out at large venues. Everyone is literally blown away when they hear how clean they sound.

I feel Proud like Pinokio's Father must have felt. Except, these babies don't lie.

[Mario Data]

Does anyone have a diagram of the layout of pieces on a 4X8 piece of ply.  I would be willing to buy the file or drawing of it.  I want to get the most out of this expensive birch.  Thanks guys.

[Mac Kerr]

Mario Data wrote on Thu, 11 December 2008 21:30

Does anyone have a diagram of the layout of pieces on a 4X8 piece of ply.  I would be willing to buy the file or drawing of it.  I want to get the most out of this expensive birch.  Thanks guys.

Are you still talking about the LAB Subs? If so, all the drawings are in the post at the top of this forum. They are available as pdf files, or as AutoCad dxf files.

http://www.prosoundweb.com/index.php/lsiuni/article/lsp_docu mentation_page_drawings_photos_specs_and_more/

Mac

[Mario Data]

I am talking about Labs, but not fabrication drawings.  I'm looking for a layout of the best possible use of a 4X8 sheet of plywood.  Someone said they had such a drawing, but I was never able to obtain that.

[Ivan Beaver]

How it is laid out will also depend on how you intend to cut it.  If you are talking a table saw, you will probably not get as much yield as if you are using a CNC machine that can do "nested" cutting, unless you get lucky.

[peter.golde]

I have some dwg's modified from the original LAB supplied dwg's, I think from Peter Sylvester or someone. I had AutoCad at the time, so I just drew out a 4x8 and a 5x5 sheet on the dwg and copy and pasted all the parts required and fit them on the sheet like Tetris. I would rough cut with a circular saw all the pieces I couldn't do on the table saw in one shot, then finish on the table saw. I no longer have AutoCad so I need to be sure what it is before posting anything. I now use Google SketchUp.

[Mario Data]

That sounds like just what I need.