If possible, yes, should be worth doing. GM is better on this than me though, so I'd hang fire for his views.
I got a cr*ppy pine, 5 ply, 15 mm, 3 x 6 feet sheet for 40 USD.
The worse thing is that it was the "premium quality".
It's pretty easy to see where wood is favored over brick and mortar just by the economy-of-scale pricing.
BTW, does anyone know how good or bad is eucalyptus plywood for enclosure building ? They had that too, worse quality but 7 or 9 ply and 18-21 mm.
Gastón
The worse thing is that it was the "premium quality".
It's pretty easy to see where wood is favored over brick and mortar just by the economy-of-scale pricing.
BTW, does anyone know how good or bad is eucalyptus plywood for enclosure building ? They had that too, worse quality but 7 or 9 ply and 18-21 mm.
Gastón
I'm sure GM will vote for double 😀Scottmoose said:
As I remember I have done the same question a few pages before and GM was the first who suggested for double baffles....
Hope I won't need 3 sheets of ply
ghpicard said:
If it's all as bad as that, I'd say blow it, go for the high-mass approach & use doubled 3/4in particleboard (chipboard in the UK) or MDF. Possibly a combination of the two -MDF for the sides, particleboard for the front, internal & rear baffles.
resident said:
I'm sure GM will vote for double 😀
As I remember I have done the same question a few pages before and GM was the first who suggested for double baffles....
Hope I won't need 3 sheets of ply
IIRC too, Godzilla's ones have chipboard front and back baffles plus a hardwood front. And are very well finished 🙂
Gastón
One of my not-yet finished BIBs
Scottmoose said:
Too late for tears 😉 ...
I finished about 3 weeks ago, with front, internal and back baffle particleboard ( 1 inch for front and back, 3/4 for the internal ) and used the ply for the sides. Not buzzing so I can assume that it's voidless or that I am lucky 🙂 .
However I'm evaluating the use of some bracing near the mouth and on the sides as discussed at some point of the thread.
The front and back feel reasonably "solid" at high SPL...
Gastón
BTW I took several photos of the build process (including the beveling of the front hole) and plan to make a small thread or a long post, but never happen to find the time to paint the sides and consider them finished enough...
Scottmoose said:
BB ply in 4 x 8 ft sheets?! AFAIK all we can get is 5 x 5 ft. Or do you mean the so-called 'furniture' grade that's usually loaded with plugs that often get loosened by the vibration and 'sing along'? This is what I used early on, learning the hard way about such things and switching over to guaranteed void free marine grade for the duration, though a few years ago I found out it's no longer guaranteed void free now that bonding technology has advanced so much. Seems to me this would ensure the guarantee rather than not, so Caveat Emptor.
GM
resident said:
Yeah, given my druthers, but I have a keen appreciation for tight budgets, so do the best you can and add stiffeners at least up the back to tie all four sides together to keep the last ~quarter from 'breathing'.
GM
>>> Hope I won't need 3 sheets of ply...
I used particle board for the front, back and inside baffle. I doubled up the front and back with pine. The sides are made from plywood. Overall, the cabinet is vibration free and very solid.
Btw, i am selling my BIBs to anyone interested. Not because they sound bad. They sound great. But i want to make room for more speaker projects.
I used particle board for the front, back and inside baffle. I doubled up the front and back with pine. The sides are made from plywood. Overall, the cabinet is vibration free and very solid.
Btw, i am selling my BIBs to anyone interested. Not because they sound bad. They sound great. But i want to make room for more speaker projects.
ghpicard said:
I've used it on several projects around the house, but no way I'd build a speaker out of it unless I knew for sure that whoever got it had a 'tin' ear. I mean the stuff I got had huge sections of lams missing out of the center causing among other things excessive splintering during cutting, especially with a jigsaw.
GM
GM said:
Yep. Believe it or not, it's actually very difficult to find anything in 5' x 5' sheets in the UK, in the shops at least. I guess you guys get that, and (if we get anything) we get the 4' x 8'. Strange, but there it is.
Actually, although classed as BB ply, a bit like your marine stuff, it's not guaranteed void free from B&Q (our version of Lowes). Material supply in the UK is generally poor -we're a ways behind Canada & the US. We can order the decent stuff of course (sometimes 5' x 5' is available depending on where you go) although shipping is another matter if you're not after a hundred sheets. And of course, you don't get to select the stuff yourself, which makes me wary.
Attachments
All this talk of wood got me digging around for some old notes back when I had a need to know about such things and found we used a void free plywood for tropical apps made to British Standard Specification BS 1088, so maybe you could requisition some through your school (University?).
WRT Gast³n's plight, they sell something called para-ply around here (or at least use to), which is pretty decent stuff made in Paraguay that we used to crate equipment to be shipped down his way and at least back in '94 when I last had current knowledge it was distributed in Selva Misionera (sp?), Argentina.
I'd forgotten about aircraft mil spec plywood, it's void free and somewhat stiffer than BB ply, but $$$.
Then there's Benelex J and Spauldite, engineered composites that have ~boilerplate specs without the electrical conductivity. Strictly for DIYers with high end budgets.
GM
WRT Gast³n's plight, they sell something called para-ply around here (or at least use to), which is pretty decent stuff made in Paraguay that we used to crate equipment to be shipped down his way and at least back in '94 when I last had current knowledge it was distributed in Selva Misionera (sp?), Argentina.
I'd forgotten about aircraft mil spec plywood, it's void free and somewhat stiffer than BB ply, but $$$.
Then there's Benelex J and Spauldite, engineered composites that have ~boilerplate specs without the electrical conductivity. Strictly for DIYers with high end budgets.
GM
Aircraft grade ply is some very nice stuff, I even have a little bit at the house but its only 1/4" and 3/16" thick, and that stuff is expensive. I believe last time I looked it would be hundreds and hundreds of dollars for a modest sized speaker build in just lumber.
For someone that wants a cheap birch ply, home depot (here at least) has some 18mm natural birch ply, they call it 'Cabinet Grade" stuff for 25$ for a 4'x8' sheet. It is not void free, but some batches are better than others. I have gotten some sheets where you would hardly find a void, and others where it is horrible.
For someone that wants a cheap birch ply, home depot (here at least) has some 18mm natural birch ply, they call it 'Cabinet Grade" stuff for 25$ for a 4'x8' sheet. It is not void free, but some batches are better than others. I have gotten some sheets where you would hardly find a void, and others where it is horrible.
And I thought, I was the only person in the world who has troubles to find good quality birch plywood! 😱
Same here. I ended up using the same Birch plywood from Home Depot for 25 a sheet. Of course, after learning that their 45 a sheet Maple ply had some voids too, although not that bad. Learning as I go. I went to my regular lumber supplier and 5x5 BB is around 65 a sheet. Pricewise, its almost that same as roughsawn lumber like maple or oak. Granted that you need the equipment to mill these down to dimensional sizes (not my problem) are there advantages to use BB to real hardwood?
Scottmoose said:
Well, I'm sorry I can't be more specific. I just got my first taste of FR and I like it. Something 'bout FR, tubes and analog... it just FEELS right. At this stage I'm going to tryout EVERYTHING. I'll be using the Home Depot birch plywood as it is only 5$ more than MDF. Exposed plywood edges ain't that bad 🙂. Would you care to share your experiences?