Retro fitting a 3012lf in a bp102-T39

[bcampbell]

You could even make the oversized panel the full size of the front panel, plus 1/2" to cover up the front edge of the top panel. Sand the bottom edge to blend in with panel 5, Duratex the whole thing and you won't see it from more than 10 feet away. Again, you could get back into the cab if need be.

Phew...I'm glad I decided not to rush through this and seek help from much wiser people. This seems like a good idea. I think if I extend the sides and top a bit more, I'll have something to screw the new access panel into...and still have access to the driver if something goes wonky later.

This has me thinking...it might be pointless, but I'll put it out there.... I have the hunk of wood that I cut out from the front (what would have been the access panel had there been room for flanges). Could I PL that to the new oversized access panel? like this...



The black piece is the size of the hole in the front, minus the width of the saw blade, so it would drop into the hole. I could then put the gasket tape flat on the new access cover so it goes around the black access cover. Perhaps that would provide a better seal. Just throwing out ideas.

[miked]

Using the cutout panel as an "insert" to partially block the hole isn't going to do much for you but add more work. If you go with my suggestion, I'd put at least a 3" width of gasket tape around the hole, leave maybe a 1/8" gap for first "circle of screws" outside the perimeter of that first ring of tape, then another 3" perimeter of gasket tape and then secure the cover panel towards the outer edges. The essential idea is to pull the center of the cover panel, the area that goes right over the cutout, down as tight as possible. That second ring of gasket tape and the outer edge screws are the insurance.

Before painting, use the hose method to check for air leaks; I doubt there will by any, but you must check. If there are, use a dab of silicone to seal it up. Paint and done.

[Grant Bunter]

As far as the old access cover goes, if you haven't got access to a router, then so be it.
just add some strips of 1/4" ply, like flanges, to PL in a piece of 1/2". Duratex and done.

Mike's idea is good. If you don't put in the old piece you can put a nice solid brace (to stop the "new" cover from flexing) on the new larger cover with out having to worry about the driver reaching it as well...

[bcampbell]

As far as the old access cover goes, if you haven't got access to a router, then so be it.
just add some strips of 1/4" ply, like flanges, to PL in a piece of 1/2". Duratex and done.

Mike's idea is good. If you don't put in the old piece you can put a nice solid brace (to stop the "new" cover from flexing) on the new larger cover with out having to worry about the driver reaching it as well...

So the old piece wouldn't do anything to prevent air leaks, got it...lots of tape...probably won't have enough room for 3 inches. But I'll put an inch or so, then screws, more tape, more screws. Probably do a quick layer of flat black for the first time out since they'll be V-plated and that side won't be visible.

As far as the flexing...Could I use the old piece as the brace to prevent flexing or does it need to be the triangular shape in the plans?
PLing the old piece on the larger one seems pretty simple, but it the triangular shape will be better, I'll do that.

Seems like this idea is getting me closer and closer. I started breaking in the 3012s...even in the open air they sound like they are going to be ridiculous.

Thanks guys.

[Grant Bunter]

As far as the flexing...Could I use the old piece as the brace to prevent flexing or does it need to be the triangular shape in the plans?
PLing the old piece on the larger one seems pretty simple, but it the triangular shape will be better, I'll do that.

Perhaps using the old piece as you've suggested will stop flex, I don't know.
The triangular brace, being perpendicular to the other piece, is most likely inherently stronger, and lighter.

I'd also suggest that you sand down your finish in the "overlap" area to make sure it's flat, to assist in getting a seal...

[bcampbell]

Well...I put the new access cover on and .... it works. It took a few rows of tape and a lot of screws, but it is on and not leaking. I put a 30 hz sine wave at 10 Vs and it sounded pretty damn good. I've got a few small holes to bondo up on the old access cover, so I'll need to test again when I have that sealed up.

I used so much tape that it isn't flush in a few spots, so I remember reading that someone put some caulk around it, just to get it a final seal, but would still be able to paint it and cut it off if later.

Thanks for all the help on this...no way I would have thought to make an oversized cover nor the plethora of gasket tape.

And sure enough, from about 5 feet away, you would never be able to tell. For those with an eye for detail, this might not be ideal. Hell, if I could figure out how to cover these with chalkboard-like material, I'd hand out chalk to the kids at the elementary school gig next week and let em decorate them.

For those that care, this was probably 4-5 hours for one cab, had to get some more gasket tape, screws, paint, and bondo, maybe like $20-25 besides the speaker. The second one will likely go a little quicker.

Pics to come soon. Well, that and I've got to do the other sub. Anyone interested in some used bp102s?

[Grant Bunter]

^ Sounds like a win

Looking forward to the pics.

All the best with the next one as well...

[miked]

Congrats! It all worked well, and that's what matters. The second one will be easier, but don't rush it (i.e. don't get cocky). I've made that mistake and sawed halfway through a perfectly good cab before I realized what I was doing.

Fact is that you succesfully pulled off what few would even attempt. You have Hidden Ninja Skills! We need a "ninja type icon."....

[ncgrove]

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