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Old 10-14-2011, 04:06 PM
CatBuilder CatBuilder is offline
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Electric Peel Ply!

I was amazed today when pulling some peel ply and saw a huge blue arc (electricity) between the peel ply and the epoxy.

It wasn't quite light out yet and every long piece of peel ply I pulled had a huge arc of electricity right at the line where it is just leaving the epoxy surface. The blue arc happened every single time.

Anybody ever notice this before??

I had read somewhere that epoxy bonded 3 ways: Mechanical (key), "some other way I am not recalling" and ionically.

Are we tearing just the ionic bond when we pull the peel ply off?

It was very interesting.
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Old 10-14-2011, 05:15 PM
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waikikin waikikin is offline
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I think its some kind of static phenomenon, I've noticed a blue dancing arc around the footprint of a grinder when used on the inside(lower light) of an epoxy/glass cat about 15 years ago, also the vacuum cleaner would happily give you a belt on the same job. Another issue I had once- I "cleverly" hung a tris' main hull from chain blocks via synthetic slings for a topsides respray, I could easily tilt the hull for easy access down each side, shot the hull & looked great but then I think every speck of dust in the shop became attracted to & stuck to the gleaming white finish- resulting in a re-sand & shot it again, this time with the sub waterline area grounded to the floor with damp toweling draped over some milk crates & cushions.

May be the cats generate an ethereal & cosmic energy 'cos they're close to perfection

All the best from Jeff.
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Old 10-14-2011, 06:32 PM
AndrewK AndrewK is offline
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On low humidity day (rare here) the static build up is very high.
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Old 10-15-2011, 12:13 AM
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Herman Herman is offline
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Try demoulding a boat hull, (without water) then grap both the boat and the mould. Good for the hairstyle!
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Old 10-19-2011, 04:38 AM
JRD JRD is offline
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Hey Cat, This is a common occurence in industrial equipment, particularly where powder or dust is conveyed over non conductive surfaces. The higher the velocity the higher the charge. What you saw sounds similar to a phenomenon called "brush static" It has a relatively low energy level but has been known to cause combustable dusts, gasses or vapours to explode with catastrophic results.
Not trying to suggest you are about to go up in smoke, but Id keep acetone well away from any source of static.
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Old 10-25-2011, 11:28 AM
susho susho is offline
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Not only boat hulls Herman, I've got some carparts wich shock me every time, especially wet lay-up with epoxy.

I was pulling some peelply out of a boathull(50 feet) once with a colleague when I saw the blue light. We turned out the light and had a lightshow
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Old 11-07-2011, 08:46 PM
Alan.M Alan.M is offline
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Quote:
Originally Posted by CatBuilder View Post
I was amazed today when pulling some peel ply and saw a huge blue arc (electricity) between the peel ply and the epoxy.

It wasn't quite light out yet and every long piece of peel ply I pulled had a huge arc of electricity right at the line where it is just leaving the epoxy surface. The blue arc happened every single time.

Anybody ever notice this before??

I had read somewhere that epoxy bonded 3 ways: Mechanical (key), "some other way I am not recalling" and ionically.

Are we tearing just the ionic bond when we pull the peel ply off?

It was very interesting.
First time I saw this I had just cleaned up some excess resin in one of my seat bases, then decided to remove old peelply to do some more glassing. The whole place was reeking of acetone, and I started peeling off the peelply - nearly **** myself!
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Old 11-08-2011, 07:03 AM
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hoytedow hoytedow is offline
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Just because we are in Florida doesn't mean we always have high humidity. In the winter I get shocked all the time getting out of vehicles or drying laundry. Always make sure there are no fumes present when peeling ply or removing synthetics from the dryer (Ours is in the garage).
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