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smug sapien
05-14-2009, 04:04 PM
This is probably going to be my one (and only) thread posted to this place because I'm not much of a car audio kinda dude, but I've run into an enclosure design problem. I figure the people here in a car audio forum have built all kinds of crazy enclosures, so you would know 100 ways to solve my problem.....

....at any rate, here goes:
I'm building a speaker enclosure out of a motorcycle top-case. The way I've chosen to do this is to chop an angular hole out of the top, then mounted the speakers in a sheet of plexi behind the hole.

Here is a picture of it
http://home.comcast.net/~infinitycrops/proj7.jpg

...and here is where I'm stuck.....

I want to hide the speakers by building a grill for it. Normally, a person could make a wood-frame and stretch/glue some fabric accross it. Unfortunately, I can't do this because of the curved irregular shape of the opening in my case, and the fact that an ordinary grill can't handle the harsh air flow from being on a motorbike.

Do you have any suggestions on what materials to use to build my grill, and how to do it?
BTW --- I can still use the speaker cloth approach, but it would have to be stretched across something solid (like a framework or some sort of sturdy mesh). I have no clue what to use to build the "framework" or what mesh to use (and where to get it). :crap:

Thanks in advance for any advice. This is the last step in my project before I ride around with it on a daily basis

SicAudio
05-14-2009, 04:53 PM
get grill cloth from parts-express.com

x2o
05-14-2009, 04:55 PM
I say go for wood. Kerf it, and it bends :)

Then cover it with grill cloth or whatever :p:

fasfocus00
05-14-2009, 04:56 PM
does that top come off? if so I got an idea for you.

galacticmonkey
05-14-2009, 04:56 PM
Buy a piece of metal mesh and stretch the grill cloth over it. Would look pretty nice if done right.

http://www.createforless.com/AMACO+WireForm+Metal+Mesh+16X+20+Aluminum+3/8+3+pc/pid137403.aspx?utm_source=googlebase&utm_medium=cse

djman37
05-14-2009, 05:26 PM
thick metal wire?? kinda like a coathanger and stretch fabric over that?

smug sapien
05-15-2009, 09:44 AM
get grill cloth from parts-express.com

Zoiks @ those pre-fab grill prices! I may need deeper pockets for this approach.
From the looks of it, they all come pre-formed in a specific rectangle. I need something that comes in a flat sheet. It would be nice if the sheet extremely solid (hard to bend), and required special tools (like a roller and jig) to shape it.
.....it would also be nice if I knew someone with rollers and jigs hehe. Just out of curiosity, assuming I picked up the yellow pages and looked for people who could shape metal, who would I look for?



I say go for wood. Kerf it, and it bends :)

Then cover it with grill cloth or whatever :p:

I've never "Kerfed" and bent wood pieces before, but if it allows me to finish my project, I'd love to learn. Can you give me an explanation on how this works?



does that top come off? if so I got an idea for you.
Yes. The top case is intended to carry things like helmets, and whatever cargo (couple of six packs of beer). There is a hinge on one end, and it opens kinda like a clam shell.
If you want to look at the specific model I'm using, its a "Shad SH26"

http://www.cbxmanmotorcycles.com/Shad-D0b2600-Sh-26-Scooter-Top-Box-Motorcase-Small-Capacity-Matte-Standard-Black.aspx

BTW -- the case is a sealed enclosure. The lid is crucial to form an airtight seal. I'm using rubber-foam molding around the edges of the plexi-sheet to facilitate the seal from the front.

I'm still curious about what you had in mind though.


Buy a piece of metal mesh and stretch the grill cloth over it. Would look pretty nice if done right.

http://www.createforless.com/AMACO+WireForm+Metal+Mesh+16X+20+Aluminum+3/8+3+pc/pid137403.aspx?utm_source=googlebase&utm_medium=cse

That's an idea.....I would probably need to make a skeleton behind it to make it hold its shape right?




thick metal wire?? kinda like a coathanger and stretch fabric over that?

Hrmmm.... yeah, that might work. Maybe a steel rod at least 1/4" thick, and the length of the diameter of the opening. I could stretch galacticmonkey's mesh over it, THEN stretch speaker fabric over the mesh.
I could hold it in place using a rubber H gasket.

I would love to do something like this - I don't have the gear at home for making precision bends in steel rod (jigs, torch, etc). I would gladly pay someone to do this though. What kind of people do this kind of work?

jdawg
05-15-2009, 09:52 AM
expanded steel from lowes or whatever

http://www.ledfordsteel.com/pics/expanded.jpg

smug sapien
05-16-2009, 09:37 AM
expanded steel from lowes or whatever

http://www.ledfordsteel.com/pics/expanded.jpg

Hey! That might work too. Is that stuff difficult to shape?

smug sapien
05-20-2009, 08:53 AM
OK -- checked out the expanded steel. (at Lowes). It's not going to work.
However --- I was able to find something that would. Have you ever seen that perforated metal they use on PA type speakers. That would be PERFECT. That's exactly what I need. It's very rigid, and shouldn't require any kind of skeleton behind it for reinforcement.

Here is the best picture I can find:

http://imgs.tootoo.com/35/9b/359bb8543a6a99b004b930556c391117.jpg

I have two questions for anybody that can help me out with this:

1. Where can I buy a sheet of this stuff (by the foot)?
2. How do I shape it?

PioneerSPL1990
05-20-2009, 09:02 AM
or you could figerglass up to a wooden frame and clean up the cut edges and then lay a wood frame and grill cloth over that.

krainium
05-20-2009, 09:05 AM
mcmaster.com should have it. If they dont they will have something that works.

djman37
05-20-2009, 10:16 AM
plenty of choices in here
http://www.parts-express.com/wizards/searchResults.cfm?FTR=speaker+grill&search_type=main&WebPage_ID=3&searchFilter=speaker+grill&x=0&y=0

buy a large round grill and cut to fit, buy the formed metal ones and cut to fit, etc.