Coating?
kv, Thu Jun 21 2007, 03:38AMwell today i wound a secondary but i need help with the coating part. At the moment the secondary is covered in tape to stop the thing unwinding itself, but how do you coat the coil without tape so it doesn't unwind itself. i have the two pieces of wire for each side taped to the pvc it's wound on. also would resin be good for coating a coil?
thanks
Re: Coating?
sparky, Thu Jun 21 2007, 05:50AM
When I wind secondaries, I always make sure the first several turns are epoxied on tight. Then I continue winding.... the tension is usually great enough to prevent any loose turns from appearing. I use 24 hr cure - clear epoxy --- I buy this stuff in large containers - I premix and then use a cardboard roller and roll on the epoxy. Once cured I overcoat with Polyurethane 2 times.
sparky, Thu Jun 21 2007, 05:50AM
When I wind secondaries, I always make sure the first several turns are epoxied on tight. Then I continue winding.... the tension is usually great enough to prevent any loose turns from appearing. I use 24 hr cure - clear epoxy --- I buy this stuff in large containers - I premix and then use a cardboard roller and roll on the epoxy. Once cured I overcoat with Polyurethane 2 times.
Re: Coating?
IamSmooth, Thu Jun 21 2007, 12:29PM
After I wound my coil I just applied two thick coats of semi-gloss polyurethane. Make sure you do it in a clean environments so you don't get bugs or dust sticking to it.
IamSmooth, Thu Jun 21 2007, 12:29PM
After I wound my coil I just applied two thick coats of semi-gloss polyurethane. Make sure you do it in a clean environments so you don't get bugs or dust sticking to it.
Re: Coating?
GreySoul, Thu Jun 21 2007, 07:28PM
I use a good gap filling CA glue (Scorpion 5) and heptane based activator as I wind coils. a little drop every few inches holds the coil together before I coat it with about 6-10 coats of shellac or spray on polyurethane. no tape needed.
-Doug
GreySoul, Thu Jun 21 2007, 07:28PM
I use a good gap filling CA glue (Scorpion 5) and heptane based activator as I wind coils. a little drop every few inches holds the coil together before I coat it with about 6-10 coats of shellac or spray on polyurethane. no tape needed.
-Doug
Re: Coating?
Nik, Thu Jun 21 2007, 10:02PM
I coat the coil form with a clear varnis and let it get tacky before winding. If you wind fast enough the varnish holds the windings tight untill i coat them.
Nik, Thu Jun 21 2007, 10:02PM
I coat the coil form with a clear varnis and let it get tacky before winding. If you wind fast enough the varnish holds the windings tight untill i coat them.
Re: Coating?
kv, Fri Jun 22 2007, 03:08AM
ok i get it now, you put little drops of glue on the windings to hold them on. what should i use to coat it? i have some resin?
kv, Fri Jun 22 2007, 03:08AM
ok i get it now, you put little drops of glue on the windings to hold them on. what should i use to coat it? i have some resin?
Re: Coating?
ragnar, Fri Jun 22 2007, 05:39AM
Purchase a can of spray-lacquer (polyurethane is especially good). You'll find spray application MUCH neater, easier, and more rewarding than any brushwork. You'll need many coats if you want it thick, but that should be no problem.
ragnar, Fri Jun 22 2007, 05:39AM
Purchase a can of spray-lacquer (polyurethane is especially good). You'll find spray application MUCH neater, easier, and more rewarding than any brushwork. You'll need many coats if you want it thick, but that should be no problem.
Re: Coating?
Sulaiman, Fri Jun 22 2007, 09:11AM
If you made a device to turn the coil for winding, use the same device to apply much cheaper liquid polyurethane varnish
(any non-water-based polyurethane varnish, matt-, gloss-, indoor-, outdoor-, yacht-, floor-varnish etc.)
Keep rotating while the varnish dries, a very smooth thick coating is easy.
A thin coating is all that's needed, but a thick coating (a few layers) protects against knocks and bumps and scrapes.
A thick coating looks really good too, but does somehow build up a static charge in TC service,
so you may get a (very) small static shock from a completely disconnected coil.
Sulaiman, Fri Jun 22 2007, 09:11AM
If you made a device to turn the coil for winding, use the same device to apply much cheaper liquid polyurethane varnish
(any non-water-based polyurethane varnish, matt-, gloss-, indoor-, outdoor-, yacht-, floor-varnish etc.)
Keep rotating while the varnish dries, a very smooth thick coating is easy.
A thin coating is all that's needed, but a thick coating (a few layers) protects against knocks and bumps and scrapes.
A thick coating looks really good too, but does somehow build up a static charge in TC service,
so you may get a (very) small static shock from a completely disconnected coil.
Re: Coating?
Kristian, Fri Jun 22 2007, 04:47PM
Would acrylic spray work for coating a secondary?
Kristian, Fri Jun 22 2007, 04:47PM
Would acrylic spray work for coating a secondary?
Re: Coating?
GreySoul, Fri Jun 22 2007, 06:18PM
As long as it's not the water clean up variety.... it should work ok.
GreySoul, Fri Jun 22 2007, 06:18PM
As long as it's not the water clean up variety.... it should work ok.
Re: Coating?
Sulaiman, Fri Jun 22 2007, 07:42PM
Acrylic spay varnish/laquer has acetone in it,
so anything attacked by acetone is not suitable.
e.g. Acrylic/PMMA, pvc etc.
So do a test before you use it - may not be suitable for all situations.
I found this out when looking for a clear varnish for my acrylic-former TC secondary,
I thought acrylic varnish would be perfect!
Sulaiman, Fri Jun 22 2007, 07:42PM
Acrylic spay varnish/laquer has acetone in it,
so anything attacked by acetone is not suitable.
e.g. Acrylic/PMMA, pvc etc.
So do a test before you use it - may not be suitable for all situations.
I found this out when looking for a clear varnish for my acrylic-former TC secondary,
I thought acrylic varnish would be perfect!
Re: Coating?
GreySoul, Fri Jun 22 2007, 08:31PM
Good point. I've always applied any spray coating with a strong solvent in very thing coatings at first to protect the underlying surface. ... you can coat Styrofoam if you coat thin enough :)
GreySoul, Fri Jun 22 2007, 08:31PM
Good point. I've always applied any spray coating with a strong solvent in very thing coatings at first to protect the underlying surface. ... you can coat Styrofoam if you coat thin enough :)
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