Thermal solutions for car amps

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What are people using for amp rework?

Where can you get mica rectangles of 46mm x 25mm?

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Would SilPad K10 be good enough? Is Sil-Pad® 900-S better?

What about this stuff, is it a kapton tape?

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Would this kapton tape be a great solution?

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Mica is very good. Why not reuse them?

You can buy them from virtually any electronics distributor.

The used kapton that you posted is Kapton MT and is very good. The roll of tape is Kapton HN and while it's OK for power supply FETs and most class D output FETs, it's marginal for the outputs in a class B or AB amplifier.
 
The used kapton that you posted is Kapton MT and is very good. The roll of tape is Kapton HN and while it's OK for power supply FETs and most class D output FETs, it's marginal for the outputs in a class B or AB amplifier.


awesome, thanks.

Mica is very good. Why not reuse them?

You can buy them from virtually any electronics distributor.
I see the ones with holes, it would be nice to have the 46mm x 25mm the used to cover 2 tip packages at once.
The originals where splintering and I got impatient and tossed them.:(
 
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Hi Chris,

Due to the cost and complexity of shipping our products to Canada, we are only able to accept orders from businesses and schools. We’ve canceled your order. If this material is not for personal use, please resubmit your order online using the business or school name.

Cheryl
330-995-5875

what the f***


Anyone know where I can get these parts?

McMaster-Carr treated me like a piece of dirt.

High-Temperature Silicone Rubber Strip
with Adhesive-Back, 3/4" x 36", 1/16" Thick

High-Temperature Silicone Rubber Strip
with Adhesive-Back, 3/4" x 36", 3/32" Thick

Super-Corrosion-Resistant Cup-Point Set Screw
316 Stainless Steel, M5 x 0.8 mm Thread, 10 mm Long
 
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It's 'probably' OK but I'd likely replace it. Something like the mcmaster 1466N12 would be good if there is enough clearance for it (there should be). That's the part number for 1/2" tape. You may need 3/4 or 1"/

Well I'm running into trouble with my silcone pads.
They seem to be too thick and they dont make contact with the smaller TO220 parts.

This is pretty stressful.

I got the kapton on there with a light skim of 340 grease but this silcone pad is giving me greif.

It is .062" which is 1/16" but you can see theres an issue.

Any suggestions?

:crying:



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Are you sure that yellow material is Kapton?

If you have it on the heatsink with 340 between it and the sink and you press the back of a finger down onto the material, does it feel about as cold as if you'd put the back of your finger on the bare heatsink?

You can use a thin piece of non-corrugated cardboard to make up for the slight difference between the large and small transistors.
 
Are you sure that yellow material is Kapton?

If you have it on the heatsink with 340 between it and the sink and you press the back of a finger down onto the material, does it feel about as cold as if you'd put the back of your finger on the bare heatsink?

You can use a thin piece of non-corrugated cardboard to make up for the slight difference between the large and small transistors.

Good morning Perry.
Yes its the MT "plus"
Its a new design that is more thermally conductive than the MT

http://www.dupont.com/products-and-...n-polyimide-film/products/kapton-mt-plus.html
 
Well as much as I wanted to just use the silicone and pretend it would be ok, I took the amp back in and I'm going to soak the old cardboard to swell it up and re-use it.
The silicone would have been perfect but the clearance is very critical and it just wans't right.

I really dont want to cook something being in a hurry.

Sucks but it shouldn't be long.

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How thick is the MT+? If it's more than 5mils I would think the lower thermal resistance would be negated by the thickness compared to 1mil HN Kapton. I've been fitting my AM series PPI amps with 1mil HN/compound after stripping the powdercoat where the TO-220 devices interface with the sink. The temp spread is much more even on them with that compared to the mica/compound over the powdercoat.
 
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