crazy idea for chassis material?

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If your so worried that RFI will affect your circuit, one could always mount a "screen paper" on the inside surface of the plastic enclosure. Just Al foil the inside if it's that cheap to ya....:rolleyes:

Personally, I would not operate a circuit (solid state) that have external component packages that exceed 100 deg C.
 
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If your so worried that RFI will affect your circuit, one could always mount a "screen paper" on the inside surface of the plastic enclosure. Just Al foil the inside if it's that cheap to ya....:rolleyes:

Personally, I would not operate a circuit (solid state) that has component cases that exceed 100 deg C.

Well, if you are talking about aluminum foil. that is a bad idea!.The aluminum foil can get loose or break and get on the circuit and get a short.
 
Well, if you are talking about aluminum foil. that is a bad idea!.The aluminum foil can get loose or break and get on the circuit and get a short.

Yeah, well that would fall under the "poor construction due to mechanical incompetence" category.:D Plenty of adhesives out there, if applied properly, would prevent such sloppy interference. Low budgets breed creativity.:p
 
I can back up SY and Magura regarding the problem with plastics not holding their shape. A couple months into my first job (as a chemist), my boss was showing me "the ropes." He had isolated a product and was going to pour it into a LDPE bottle to save. I remember asking "isn't that a little hot?" (It was >100C.) "No it's fine" was the answer. He transferred the product, and we both watched the 100 mL bottle slowly transform itself into a warped little 15 mL bottle, disgorging its contents onto the lab bench all the while. It was all I could do to not laugh my (ahem) "fanny" off. :rofl: The good news was that I didn't have to suffer any more "training". :rofl:

You don't want this to happen to your amp, especially when it's plugged in.

You see, this wasn't completely OT. :D

Looney (and still laughing) :rofl:

See, that was a lesson in the "memory" effect of plastics.
A lesson one could easily get a repetition of, if using the wrong material, or applying it wrong ;)

Magura :)
 
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Yeah, again, there's nothing wrong with plastic, it just has to be the RIGHT plastic. "Plastic" encompasses materials spanning an enormous range of melting points, stiffness, flammability, conductivity... The proposed source (cutting boards) is just a lousy choice for any device that will have significant heat.
 
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Yeah, again, there's nothing wrong with plastic, it just has to be the RIGHT plastic. "Plastic" encompasses materials spanning an enormous range of melting points, stiffness, flammability, conductivity... The proposed source (cutting boards) is just a lousy choice for any device that will have significant heat.

Cutting boards are HDPE, which according to Wikipedia has a somewhat higher maximum temperature than what has been suggested in this thread (120 °C/ 248 °F for short periods, 110 °C /230 °F continuously).

HDPE is very easy to cut but it is difficult to glue. There are some special epoxies that will bond to it but for the most part it is quite resistance to solvents and adhesives. However, threaded inserts and nylon screws work well.

I like the "saw dust" that it creates--it is so fluffy you could almost make a pillow from it. The second picture shows a speaker using quite a bit of HDPE. These speakers were called the "Marthas" because the first round of HDPE used Martha Stewart cutting boards. The packaging at Kmart even had www.bluelight.com on it, so the illumination concept kinda grew from that...

HDPE.JPG
Martha_top.jpg
 
12volts! But how many amps is the car battery again? big difference!. it is not the same volts and amps!!! it can be 24v but if it is 100mA it is nothing!!!
I do not think we are talking on the same page here.:confused:

I asked you what's in the amp that will give you flames or smoke that's not in the loudspeaker.

You answered high voltages, seemingly as if you were saying that only high voltages can cause flames or smoke and that low voltages cannot.

Is that what you were saying? If not, then why did you say "high voltages"?

se
 
For some comercial gear that had to get UL rating (live mains inside) we had to use Lexan 940, a polycarbonate, generaly would use an ABS/PC blend as it moulds easier and is more flexible. Polycarbonate can be a bit awkward to work with if your using panels, you can get stress fractures around fixing holes, as I found out when my beatiful polished clear polycarb amp housing distintegrated over time. I had used counter sunk holes for the fastenings with sharp corners (concentrates stress in some plastics).
Goto second what Steve Eddy has sd on screening, a lot of products in plastic enclosures arn't screened as the cost of screening can double the price of an enclosure, instead its best to solve the problem at the PCB layout stage.
 
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