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dixontj93060

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Many years since I have been on a technician's bench, but I would never trust electrical insulation to a spray on coating--too thin and easily scratched. Use nylon washers/spacers, poly mat or shrink wrap depending on the size/shape of what you are trying to insulate.
 

Trenman

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Does shrink wrap really work? Nylon spacers sound doable. Is there a polymer dip perhaps? I have these really nice pieces of anodized aluminum that I really want to make work. For my application it MUST not conduct.
 

bobkrech

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The way to make aluminum surfaces non-conducting is to have them anodized. Type II and Type III anoziding are non-conducting, however Type 1 is conducting.

However anodization is a surface treatment, so if you tap it and then thread it and put a screw into it, it still will conduct. This is not wise in any case, because anodization converts the top several mils of surface into aluminium oxide, (sapphire or carborundum) the second hardes materaial around and it will dull tool bits and taps and therefore all machining must be done before anodization.

A word of warning. I have designed electronics packages to survie 4,000 G crashes into the playa and 20,000 g gun launches so I have a bit of experience here. Electronics mounted on stand-offs is not recommended in high g environments because the stand-offs can break because they alone carry the g-load of the circuit board. It is much better to use milled channels (slot) on vertical edge guides and mount the circuit board in slots directly on the bulkheads. They can't break this way.

Large capacitors should be epoxied to the circuit boards becasue they will break their leads if that's all that's holdiong them in place.

Bob
 

NjCo

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Is there a polymer dip perhaps?
There are those dips used for the handles of pliers and screw drivers. You might look into that. I've never used them but I do recall cutting a live electrical wire with wire cutters that had something similar on the handles and I'm still here to talk about it!
 

BHP

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A word of warning. I have designed electronics packages to survie 4,000 G crashes into the playa and 20,000 g gun launches so I have a bit of experience here.

Bob
WoW!
 

dixontj93060

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Well maybe not 4000g, but my electronics survived this pretty serious lawn dart a couple of weeks ago:

 

MarkII

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Yeah, I wondering a bullet fired into a concrete wall would be subjected to that much force when it impacted... :eyepop:

MarkII
 
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