If your are sipping your coffee or any other beverage as you read this, please swallow what you have in your mouth and put the cup down. I’m not taking responsibility for any spit takes that might happen when you see what I made.

It started a couple of months ago when I was fooling around with some scrap aluminum and the TIG torch. I was adjusting the welding machine settings and rod size seeing what effect various changes had on welding outside corners. As I welded bits together I realized I could make a box of sorts and that would provide good practice on the seams. Well, i made the box, enclosed on 5 sides and I looked at it… what if I make it into a subwoofer enclosure?

3/16″ thick aluminum is not what springs to mind to use to make a speaker box, but what the heck eh? I had a pair of 12″ speakers in the garage, no idea what make, and I decided to use one as a sub. I added the 5th side to the box, actually pieced together from 4 bits, and cut a hole for the speaker. And why not four bits of tubing for legs? This was going to be a down firing sub. Oh and it was going to be a sub that paid very little attention to volumes, Q factors, etc, etc.

I drilled and tapped holes to screw the speaker to the box, than I made a grill from some 1/4″ square section material. The grill pleased me, stiffer than I expected. And just because I worried about how to secure the beast in the van, I welded on a couple of half moon bits to have something to attach a strap or something.

Ok, so it looked kinda bare. But I was recently given some leather so I thinks to myself “a leather pad thing on top would gussy it up some”. I cut a square of leather, a round of sleeping pad type foam, and some canvas as backing. I sewed it all together (and I found that difficult, only sewn a little bit of leather before and never saddle stitched) and attached it to the box with a leather thong.

And now it looks like some sort of industrial ottoman or commode. Go on, look at the pictures and laugh, I’m used to it now.

(Looking inside you might be able to see some dampening pads stuck on the walls)

Ta-da!

Yes, the sides are curved. Same scrap material that I made the underbody protection plate  with.

Paper cone and still in one piece.

So how to power this thing? My head unit has 2 channel sub out jacks and I knew I had a spare amplifier in the workshop. An amp that was bridgeable so I could lead 2 channels in and have one channel (mono) out. I couldn’t find the damned amp, I searched high and low. Found all kinds of things (previous posts) but no amp. Good friend Stephen took pity on me and gave me an amp he had lying around. Nice old amp, a Blaupunkt 4 channel unit.

It was not bridgeable, but it excited me. The existing stereo set up in the van consisted of a Pioneer DEH-P5000 head unit feeding an Alphasonik PMA-2030 amp (not bad vintage amp) under the driver’s seat. That amp powered the front door speakers, Boston Acoustics Rally (model number forgotten) 6″ mid in lower part of door and tweeter up behind stock speaker grill. Oh and those are fed via some separate BA crossovers. Back in the rear overhead cabinet are a pair of 4″ pioneer speakers, powered directly from head unit.

I decided to pull the Alphasonik amp (not bridgeable) and use the Blaupunkt to power the front and the rear speakers. Was a little bit of a pain to do that, but I did manage to reduce the tangle of wires behind the dash (I can’t really fault the previous owners of the van, stereo installs seem to bring out the slipshod in all of us) and I squeezed the amp up on the crossmember behind the glove compartment.

That all worked well. When I say well I mean the stereo system still worked. But I don’t have my sub installed! Where the heck is that lost amp?

I found it the other day, not far from where it was supposed to be. It had fallen, or was placed (yeah, by me) in a box of fibreglass cloth and was covered by same. Callooh callay! I cried (no, I didn’t) when I found it. Some futzing and farting around and it was installed under the driver’s seat and finally my sub made noise. And what kind of noise? Well, a kind of thumping booming noise. It does pump out the bass, it does make things rattle, and once I fiddled with the sub woofer settings on the head unit (low pass and high pass filter adjustment) it sounded rather ok. I don’t think it is as tight or as controlled as a subwoofer should be, but considering everything about it, it is acceptable.

I have it connected to the amp via an RCA jack so it is easily disconnected and removed from the van. Right now it sits behind the passenger seat, but I can extend the cord and I might try other placements.

Oops, forgot, I made a quick sketch of the stereo system layout. Note the connections between head unit and both amps are via RCA jacked lines.

At the end of my last post, the beginnings of a trailer hitch, I showed 2 pics of my iPad Mini mounted on the dash. It was a start, a Mk I if you like, to see if I liked the position. I used some found coaxial wire, about 0.6″ diameter, aluminum wire core, polyethylene, aluminum sheath then vinyl cover. Or something like that, the point is the stuff bends and holds. It doesn’t bend back and forth forever though. Anyhoo, that and a swivel mount I made (aluminum and teflon on the moving parts), some plumbing fittings, and a pretty crudely made plate on the ashtray hole.

I did try mounting to the inside of the ashtray, and I managed to do it. But the ashtray wouldn’t stay in place with all the weight and I broke the damn thing trying to solve that problem.

I didn’t like the high position of this mount so back to the bench. More bits of scrap aluminum, some 0.5″ stainless tubing, and further dicking around ended up with something that looks more surgical than automotive. Man, I need some sense.

The swivel mount has some Velcro on it. I’m using that to connect to the Otterbox Defender case (the cover part that doubles as a back and a stand). Velcro is not great for this, but was all I could come up with for now.

Crude tabs to hook into dash. USB extension cable for connection to stereo head unit.

I made the arm a bit too long, I’ll trim it back. I like this position better and yes, you can still shift gears.

Swivels to landscape.

I agree, it is a bit clunky. And what to do with the cable? I don’t want to run it inside the tubing. Maybe I can figure something out to make it less untidy looking.

Update: I weighed the bumper as you see it below, it’s 9.2 kg (20.3 lbs). For comparison, the stock chromed steel bumper, minus plastic end caps, weighs in at a svelte 5.6 kg (12.3 lbs)

A little progress made on this project. Made up a more or less matching end cap and also did some preliminary grinding out of the welds. What a chore this way of making a bumper this is.  You understand don’t you, that this is me making it up as I go along, modelling (I can hardly say sculpting can I?) a bumper out of aluminum plate. Once I get a shape that I like and that works then I can take measurements and think about how you could make one easier and faster.

I really didn’t think through the bumper to endcap transition did I? Here is what my doodling around resulted in.

I have to be clear and say again that I’m winging it. I’m doing in aluminum what I should be doing in cardboard or thin plywood. So to fix the blunder, I cut the endcap up a bit, angled the bottom plate to match the bumper bottom plate, added another filler piece then welded it up and roughly smoothed things over. It is a lot better now, this might be the one to keep.

I didn’t take too much time grinding the welds, but enough to get the idea of how I want the corners to look.

Both bottom plates, bumper and endcap, meet up a bit better. I’d like to radius or smooth out the inside corner also.

Next thing to do is to double check fit on van, smooth out some wavy edges and corners, then make a matching (ha!) endcap for the other side.

As if I don’t have other things to do, I’m making a muffler for the van. I’ve had the idea for years so why not give it a go eh? Scrounged materials used:

– perforated stainless tubing for the straight through internal pipe, 2.25″ diameter, wall thickness about 3/32″

– a section of 6″ diameter stainless tubing for can, again about 3/32″ wall.

– 2″ diameter stainless tubing for in and out pipes, 3/32″ wall.

– some stainless sheet for end caps, a hair under 3/32″ thick this time.

– stainless swarf from some big ass lathe for internal packing.

I made a start yesterday, got good buddy Dave to do the TIG work, hope to have it finished in the next couple of days.