BillFitzmaurice.info

I am getting started on my 14x32x32 AutoTuba. Here is a link to my "Q&A" thread.
http://billfitzmaurice.info/forum/viewt ... =5&t=23327
It will be mounted in the bed of my 84 Ford Ranger standard cab firing into my seat back through a "blow through"

The driver I am using are a pair of 1998 vintage Rockford Fosgate RFP2408's
http://www.rockfordfosgate.com/rftech/l ... LC_MAN.pdf



I spent a few hours reading over the plans then headed out to the garage.

It's official, the build has started.

The first side panel cut and marked out. Two of the external dimension cuts are rough because I will trim those flush after final assembly.


Please forgive my photo quality, I took them with a potato.

Good start! That looks like MDF, that is going to be heavy! Make sure you brace it properly, I figure 3 sets should do it.

MDF for the win.
I HATE plywood to begin with and no way was I going to mess around with warped panels. Not to mention MDF is a lot easier to machine and finish in my opinion.

The weight is actually a good thing, helps balance out the weight of the 5.0L HO under the hood of a 2800 lb. truck

Thanks for the Intel on the bracing.

Jwsewell wrote:MDF for the win

Not once it gets wet. MDF SUCKS! The dust from cutting is very poisonous, it's much heavier and structurally weaker than even fair quality plywood. Being as this is in a vehicle, subject to swings in relative humidity, forget the MDF. If you follow the instructions in the plans, warpage is a non-issue. Use true Baltic birch plywood, a/k/a Russian or Finnish birch plywood, and never look back at MDF.

+1
I had to give it. I know that you've built several cabs before but this one is different.

The only subwoofer enclosure I ever got rid of due to water damage was built out of 3/4 plywood. It was that Lowes Baltic Birch and it did have the thin outer plys.

I have been using fiberglass resin to attemp to waterproof my enclosures. MDF seems to soak up the resin better than plywood but polyester resin is not waterproof like expoxy resin as I have discovered.

I have a MDF "test box" in the bed now getting soaked by the worst the Pacific NW can give it.
This box has been coated with "bondo milkshake". ( bondo and fiberglass resin mixed) and then painted with epoxy paint.

In other words, I'm using MDF. ( I think)'. Lol. I already had to talk myself down from using 3/4" MDF for side panels with 1/2" deep dado grooves. Lmao!

Not that I'm not thankful for all the advise.
I do want to rest your minds a bit though. I completely understand the health risks involved with MDF dust which in my opinion is the biggest issue using it.

Besides, I don't fail. I learn.

DJPhatman wrote:

Jwsewell wrote:MDF for the win

Not once it gets wet. MDF SUCKS! The dust from cutting is very poisonous, it's much heavier and structurally weaker than even fair quality plywood. Being as this is in a vehicle, subject to swings in relative humidity, forget the MDF. If you follow the instructions in the plans, warpage is a non-issue. Use true Baltic birch plywood, a/k/a Russian or Finnish birch plywood, and never look back at MDF.

I think you forgot to mention how it burns through expensive carbide saw and router blades and strips screw holes like crazy as well!

All the advice aside, it'll work just fine for the autotuba as it will be in a permanent location. I've used MDF for dozens of boxes for my cars over the years. I've since been converted to Baltic birch . You may want to use real wood for the driver retention blocks and to rim the access cutouts so the screws have something to bite into. Man that box is going to be heavy, much heavier than you can imagine with all the bracing inside. Probably going to be a 2 man job to get it into position.

Jwsewell wrote:The only subwoofer enclosure I ever got rid of due to water damage was built out of 3/4 plywood. It was that Lowes Baltic Birch and it did have the thin outer plys.

Lowes doesn't sell Baltic Birch. By definition, Baltic Birch has equal plies and is usually found in 5x5 sheets (occasionally in 4x8). What you had was probably cabinet grade birch which is a whole different animal.

CoronaOperator wrote:

DJPhatman wrote:

Jwsewell wrote:MDF for the win

You may want to use real wood for the driver retention blocks and to rim the access cutouts so the screws have something to bite into.

That is advise I will use for sure! Thank you!

Bruce Weldy wrote:

Jwsewell wrote:The only subwoofer enclosure I ever got rid of due to water damage was built out of 3/4 plywood. It was that Lowes Baltic Birch and it did have the thin outer plys.

Lowes doesn't sell Baltic Birch. By definition, Baltic Birch has equal plies and is usually found in 5x5 sheets (occasionally in 4x8). What you had was probably cabinet grade birch which is a whole different animal.

I think I kinda knew that going into it it. Lol.

Damn Y'all, now I think I'm gonna hunt down some real BB and give it a shot.

Lol

The build is going to held up for a bit anyway, I have to figure out what on earth is wrong with my GF's 2003 Turbo Beetle. I just repaired a broke air injection valve the other day and last night on her way home the CEL started flashing and the engine has no power. So I have to figure this out so she can drive it while her other car goes into the body shop........ UUUGGGGGG!

Audio addiction is best when your single. Lol

Jwsewell wrote: Damn Y'all, now I think I'm gonna hunt down some real BB and give it a shot.

Lol

I found a place in Portland called Mr. Plywood. I'm betting he will have what I need.

Yup, I think so. I just called and its $38 per 5x5 panel. He said 9 equal layers, that sound right?

Jwsewell wrote:
Yup, I think so. I just called and its $38 per 5x5 panel. He said 9 equal layers, that sound right?

That's the stuff! Also buy a good set of tweezers and a magnifying glass, Baltic Birch splinters (slivers if you are in Canada) are the worst!

Jwsewell wrote: Damn Y'all, now I think I'm gonna hunt down some real BB and give it a shot.

You won't regret it. I'd never used baltic birch until I started building these cabs....now, I won't use anything else....for anything. It's flat, stable, and no voids. I build all my cases out of it along with other projects outside of speakers.

Bump Build Update?