2016 Porsche Macan S - stealth SQ build

[diy.phil]

Hey, you're doing fine Ge0. The way you do works nice and we all do the same for the longest time and still doing it.
Yeah some 3d printed or cnc/formed brackets can work too. You can save space or weight but not money lol. If you can use a CAD software, just go for it now!! There'll also be endless projects inside the house and backyard with CAD. (I actually have not been to any CAD school other than 1 semester of 2d drafting during freshman year... not too difficult.)

[geolemon]

Is there enough clearance behind your 1/4" material to make some circular discs, maybe an inch or two in diameter, and bond those behind your mounting holes? That way you get your mounting location thickness, without needing to re-fab the entire panel?

Besides plastic welding, I know ABS can be tricky to bond - we used to have some CA glue that worked, but I was always skeptical of the bond. So - I'm not sure what kind of insert you are using, probably threaded - but Parts Express carries these Hurricane Nuts that would actually clamp everything together, if that would help:
(note these insert from behind, so the flat disc is behind)

I think I actually have a ton here... I'd be glad to ship you some for free. I'm never going to work through my stockpile.
Let me know what hole size your amp mount holes are, and I"ll see if any of my sizes fit. I'm 99% sure mine will.

[cueball981]

Geolemon,

Thanks so much for posting up an incredible detailed response! I really appreciate you taking the time and I will check out all the links you posted within.

Looking forward to making some sawdust...er...plastic shavings! I definitely want to improve my skills on the router table!

[geolemon]

...I need to counter-sink the amp board mounting screws. This will not work with 1/4" material. I need to go down at least 1/8" inch. This doesn't leave enough material to be mechanically strong. So, looks like tomorrow I copy this to a 1/2" sheet.

Glad I read this again - I misunderstood which screws you were worried about
Those mounting screws - looks like you are trying to re-use the factory bolts, right? Those are pan-head, which stick up, which mean you need to cut a cylinder-shaped recess - which will make for a weak spot.

Why not just swap out the bolts for simple flat-headed phillips screws? It's like $1.20/bag at Home Depot. Even with their crappy selection of hardware, they have SAE and metric (I'm guessing yours are metric, bring the screw with you to match up), even stainless steel, cheap.

I'd bet you own a counter-sink, and that wouldn't create that weak spot:

[Ge0]

Is there enough clearance behind your 1/4" material to make some circular discs, maybe an inch or two in diameter, and bond those behind your mounting holes? That way you get your mounting location thickness, without needing to re-fab the entire panel?

Besides plastic welding, I know ABS can be tricky to bond - we used to have some CA glue that worked, but I was always skeptical of the bond. So - I'm not sure what kind of insert you are using, probably threaded - but Parts Express carries these Hurricane Nuts that would actually clamp everything together, if that would help:
(note these insert from behind, so the flat disc is behind)

I think I actually have a ton here... I'd be glad to ship you some for free. I'm never going to work through my stockpile.
Let me know what hole size your amp mount holes are, and I"ll see if any of my sizes fit. I'm 99% sure mine will.

Maybe I didn't make myself clear enough. My problem is with these bolts:



In order to mount the amp and MOST25 adapter flush to the board I would need to countersink these 4 screws. Doing so would make the material weak at this point. There would be less than 1/8" of plastic left to hold the rack. Now that I have the template made replicating it in a thicker material should only take an hour or so. I would feel much better about having a secure mount for $1800 in electronics

Ge0

[cueball981]

I'm really liking how your install is going! Great job with the plastic rings and amp rack!

[geolemon]

Maybe I didn't make myself clear enough. My problem is with these bolts:



In order to mount the amp and MOST25 adapter flush to the board I would need to countersink these 4 screws. Doing so would make the material weak at this point. There would be less than 1/8" of plastic left to hold the rack. Now that I have the template made replicating it in a thicker material should only take an hour or so. I would feel much better about having a secure mount for $1800 in electronics

Ge0

Yep, sorry - I realized that after the fact.
That's why I made the other post, after it. This one.
I think replacing the bolts would be your simplest bet, without adding extra bulk expense and rework.

[Ge0]

How about some speaker porn?





















Ge0

[Ge0]

OK. I'm pretty anal about my work and needed to redo my amp rack. The 1/4" material was just too flimsy for my comfort zone. It only took a few hours. So, here we go...

Trying to align HDPE templates sucks. The pieces slip and slide against each other like Teflon or Astro Glide. That and the 1/4" board was warped from the supplier. This made the job even more tricky:



Use the mounting screws as indexes for the new template







Chamfer your edges of course. Don't want to cut yourself on sharp edges. Plus, it looks slick.



Man these counter bore bits look mean.



Short work oin the drill press and complete. Definitely use a drill press here. If not your countersinks will turn out crooked.







All done. Timefor a desert.



Ge0

[Ge0]

Test