Bought the Civic Hatch lease out, so rebooting the install thread

[geolemon]

On the fabrication front, I guess I leaked a convertible aspect of this install here:
https://www.caraudiojunkies.com/showthread.php?p=71981

But anyway - all that shopping and at least I've made pre-templates so I can make the two templates I need for my three panels (one amp rack, two swappable sub box). These will allow me to get the so the recesses and holes drawn uniform and correct.


I think I'm going to like that mechanical industrial aesthetic beyond the functionality it's really being used to mask - it suits the robot look of this Civic.

Now I'm back to thinking maybe I will find somewhere to use this hex-mesh plastic I picked up - it matches the Civic hatchbacks fake bumper vents, and that industrial vibe.



We'll see.

[geolemon]

Quick update -

Been busy with the 9-5 IT projects, plus a backyard project that involves contractors and coordination so those take priority...


But I've managed to make important progress on all the details that need to happen - one at a time.
And it is coming together - truly at the point where I'm ready to stretch and 'glass:


I wanted to include a couple pics to show how the two chambers are connected, since I think it's been unclear.

I'm aware it's tough to get a sense of scale, it's about a 14"x4" opening, and the inside bottom of the top chamber has been cut back and rounded all around the inside to make it invisible - I even drilled out the magnet support brace to make it transparent and allow the chambers to perform as one:



A couple things might look rough still - the holes in the baffle aren't really "the baffle". Those are pass through holes for the mounting hardware, clamping the sub to it's adapter ring, using the mounting ring/inserts to clamp it all tight together.

That ring is finished - here's the back so you can see those inserts, and I drew a line so you'll see where I'll eventually cut it, so it can be installed (so it can also potentially be removed, when I want to swap in OTHER subs). The holes in the baffle align with this:

The ring of eight holes is for the JBL, the ring of 12 holes is for the JL.

Down below - you'll see I'm still doing work on the coupling inserts:

I have to keep these two as separate pieces or they won't go in, so I want to make sure those two parts couple closely and seal absolutely - one part of that recipe is to use inserts and bolts.

These are good inserts, but tough to use in plywood. So I installed them, backed them out and removed any questionable chips. I mixed up some JB Weld and filled those chips in, while also sinking the inserts where they need to be. I also gave them some rear clearance drilling before I set them in the final time.

I'll need to belt sand this flat once it cures, but I should have a good, flat mating surface with strong inserts to bolt these tightly.

Still debating whether to use a gasket or silicone it, I'll decide at install time.

Next it's time to wrap fleece and 'glass. I might even use fleece in the lower chamber to make life easier - we'll see.

[geolemon]

My fiancee was impressed with my choice of fleece from the bargain bin. Too bad the donuts and ice cream won't be visible in the final product

Ended up with people over so I didn't do anything with the lower piece, but at least got a chance to get this first shape layer resined.

You can see now why I made that plastic piece to use in the stretching:
With the massive amount of pull I ended up having to do on this, I wouldn't have wanted to leave that kind of tension on the piece overnight, without resin.

Next on this part, my plan at this point is to do just a little build up on the outside, maybe some strategic chopmat and then woven - then I need to cut that sub hole open and really bulk it up from the inside. Break out the double-stitchmat.

This isn't the thickest fleece (literally did the bargain bin at JoAnne) but it's still thick enough for a little of that I-beam effect with layers on both the inside and outside.

[geolemon]

Adding yet more unnecessary complexity for performance benefit -
I caused myself another engineering challenge.

Earlier I thought I'd be able to join the upper and lower chambers permanently, but in a test run it's just not possible to get it in as one piece.

The benefit of making it one piece is that I could get rid of the wood on the floor, to increase the size of the opening, connecting the upper and lower chambers.

The downside (now that I'd already optimistically cut it out) is that I don't have 360 degrees of flange to connect the two parts together...

So now I'm engineering a small flange that will set further back from the main flange (so the opening will be just as large) and also use threaded inserts, and I'm going to have to make that joint between the two flanges on both sides seal up tight as well.



I'll still roundover the top for flow and add something to the bottom to let me 'glass securely to this, and need to clean up the mounting surface - but it should be just fine.

I probably am at the point where I'm not going to escape from needing to silicone all around these seams, but that's ok since the goal isn't to make this easily removable. by any stretch. If it ever needs to come out - it'll be part of the disassembly process.

[geolemon]

Between the work urgencies and patio remodel its been feeling like I'm never going to get this glass laid...

But last night I put down a layer of foil and then covered that with two layers of high-release painters tape - the plan of course being to set the frame in, and start layering directly to the well. Hell, with this kind of double-release I could pour resin in there and sop it up with mat and cloth pieces, if I want.


But then I thought about my time limitations again, and since I had an extra 30 minutes, and had plenty of fleece left - I decided to stretch fleece on the backside of the frame... I'll tell you why in a moment.


This makes my foil-and-masking laughable overkill since hardly any resin will make it through if I use it right - but that's ok.

What this lets me do is get a fleece layer rigid, just like the top piece - then I can remove it - and I'll have two pieces that need to be built up.

Then I can build them up together - cut my pieces of biax and mat, and that will be much more time efficient for the dribs and drabs of time that I have to work within.

Here's the piece after resin:


And now it sits overnight.

I thought I'd be able to pop it by bedtime, but it's still not feeling rigid like my upper piece did - I thought I saturated it as much, but maybe not. So if it's not properly stiff by tomorrow, I might have to at least do a layer of mat before I pull it out. I definitely don't want to have my additional layers cause it to warp out of shape.

[chithead]

This is amazing! Really digging the attention to detail and engineering you've put into this build.

[geolemon]

This is amazing! Really digging the attention to detail and engineering you've put into this build.

Ha - thanks.
Lots of headaches I'm causing myself just by trying to maximize everything and not giving myself any extra margin or tolerances.

Like I said a few pages back - I'd have fired a fabricator at the shop for wasting so much time and money

I like the way you worded it better

Sent from my LM-G820 using Tapatalk

[geolemon]

I had my patio to finish (even worked in some LEDs there ) and a vacation to go on, so just getting back to work on this.



Really wanting to pick up the pace - need to get this in. Can't start the A pillar fab until the rest is installed, really.

So one thing I forgot when I cut out the top of the lower sub box, was that my upper chamber is going to have rings that push it out an inch - making the flange for the removable part too narrow right where the baffle goes over it.

So I made this strip routered out of 3/4" birch ply:


And that's being glued and clamped solidly to the 1/2" birch ply that the 3/4" cover panel will be attached to:



Also got the two little pieces fabbed and bonded in place to complete the flange where the upper and lower pieces bolt together - looks rough but it'll be sanded and ultimately siliconed.


With the clamps off, and holding the spacer rings in place, you can see why this would have been a problem.

[geolemon]

Completing the fiberglassing is a milestone because:

1) Until this is completed, there's other aspects of the fabrication that I can't move on to. I'd be painting myself into a corner.

2) This has been making the whole timeline slide - it requires a fair bit of prep, including prepping the facility, tables and dropcloths, having the pieces laid out where they can stay and cure for hours... then of course time to work through it - so it's been tough to find a day to do it.

Now, I'll be able to get back to making progress.

I bought a ton of stitchmat in the interest of time - I love this stuff. It's just cloth stitched to mat, but it makes it the best of both worlds. It builds up fast, is rigid, you can work fast with it because the cloth helps hold the mat together, and ends up reasonably smooth, like cloth.


I took these pics this morning - interesting to see the difference in these resins.

So I had a gallon of Silmar surfboard resin (polyester), but I was worried about running out so I picked up a quart of Bondo polyester resin locally just in case.

The Silmar is so nice, cures clear. The Bondo has that sewer sludge color.

Sure enough, I had enough Silmar to do the bottom chamber and roof of the upper chamber, then I had to switch to the Bondo resin. You can really see the color difference in the pic of the upper chamber-

I did the lower chin in the Bondo brown, and I did add a few extra pieces to the ceiling to use up what I mixed up.

I also added one piece to the lower chamber right at the last possible moment before that resin started to gel up - and you can definitely see which resin is which - but this is all hidden inside so the ugly brown doesn't matter.

I do still have some resin and things still laid out, so I may use that up tonight if I find any spots I want to thicken up.

Then, moving on to finishing it and installing...

[Chris12]

I'm sure you already know but..
Make sure to sand before you add additional layers to anything with cured bondo resin. It's got wax in it.

Lookin great!