# What's the deal with Baltic Birch plywood?



## mhammer (Nov 30, 2007)

I see it touted in ads from time to time, and a terrific wood store near me has it in 4 x 8 sheets. It's certainly pretty, but then cabs are generally covered up by tolex, so I'm assuming that it is desirable for speaker-cab building for reasons other than how pretty it is.

So what are the reasons? Is it strong for its weight or something like that?


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## zdogma (Mar 21, 2006)

It has more laminations and less voids compared to regular birch plywood. Generally it has 9 laminations in the approx. 1/2 in (11mm actually) compared to 3 to 4 for typical plywood. Is it stonger? I think it probably is. I do find it heavy. 

Avoid the Chinese birch plywood. It has lots of laminations like the Russian birch ply, Looks very similar, and is cheaper, but the quality of the wood is lower, and it deteriorates quickly with wet/damp conditions (like basements). 

Baltic birch is the best material available for baffle boards IMO, and makes excellent quality, tough if heavy cabs. Personally I like the old loose, rattley pine cabs better (like your old tweed Bassman!)


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## shoretyus (Jan 6, 2007)

What kind of speakers are you building?


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## mhammer (Nov 30, 2007)

I didn't have any immediate plans to make a cab, and certainly have plenty of wood in the garage taking up space that could be used for the task. I was just interested since I had heard different companies trumpeting their use of it, and had stumbled onto a local source of it for the first time. I was just wondering if it was something I should be predisposed toward....not that I need any more spare lumber in the garage.***


***Ironically, we recently had to rearrange things in the garage and move a heavy, but high quality, radial saw I inherited from my late father-in-law. My brother-in-law described him as being "someone that no piece of scrap lumber in the neighbourhood was safe from". The radial saw was actually a surprise to us, and was buried under a mountain of spare lumber that filled up virtually every available cubic foot of the garage. Having learned the lesson, I'm not all *that* eager to buy lumber I don't have an immediate use for!


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## dwagar (Mar 6, 2006)

IIRC Baltic Birch should be void free, high quality for cabinet use. 

Funny about the old radial arm, they don't get much love any more. I picked up an old Craftsman Radial Arm at a garage sale a few years ago for $50 - the old Gold series, not the newer black plastic ones. I stuck at the end of my workbench just for making square cuts. The thing will crosscut something like 16". Gotta be right up there as one of the most dangerous pieces of equipment in the shop though.


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## jimsz (Apr 17, 2009)

I've used a fair amount of BB plywood in building telescopes, telescope cases and eyepiece cases. Great stuff. But, I wonder how you managed to get it in 4x8 sheets as traditionally BB plywood comes in 5x5 sheets?


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## mhammer (Nov 30, 2007)

jimsz said:


> I wonder how you managed to get it in 4x8 sheets as traditionally BB plywood comes in 5x5 sheets?


Well your *knowledge* trumps my *memory*. :bow: I just presumed they would have been 4 x 8, but now that you mention it, they _were_ kind of square and small-ish.


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## jimsz (Apr 17, 2009)

mhammer said:


> Well your *knowledge* trumps my *memory*. :bow: I just presumed they would have been 4 x 8, but now that you mention it, they _were_ kind of square and small-ish.


When you check it out, look very carefully at each side, usually with B grade, you'll get one side that is free of defects but that's not always the case. You may find oval shaped patches where defects were and you don't want to have those show up in your work. Often, I have had to find sheets where the patches are near the edges and just cut those away for scrap. As most things with production, you could also get a run where the production equipment was faulty. For example, I bought a couple of sheets one time that appeared okay, but when I was finishing them, all of a sudden crosscut ridges from a bad saw started appearing that ran against the grain. This became very apparent once I began to stain the wood. I eventually sanded out the ridges but it was extra work. Hope this helps.


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## geezer (Apr 30, 2008)

I've used lots of baltic birch for drawer boxes when I did runs of commercial grade furniture and it was great but have had problems with sheets being warped and with ridges transferring though when
I vacuum pressed veneer onto it.I have never made speaker boxes from it but have seen it suggested on Bill Fitzmaurice's site.(awesome designs)


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