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-   -   Re-spraying record decks. (https://www.vintage-radio.net/forum/showthread.php?t=162342)

Michael Maurice 21st Dec 2019 11:44 pm

Re-spraying record decks.
 
Occasionally I come across record decks, mainly BSR and Garrard where there is either rust or paint coming off. If I wanted to re-spray it, how would I go about it?

What paint would I use? I usually buy car paint from say Halfords. Can I spray straight onto the old paint, or do I need to strip off the old paint before I spray?

Uncle Bulgaria 22nd Dec 2019 1:26 am

Re: Re-spraying record decks.
 
2 Attachment(s)
With my GL59, I took everything off (it was flaking, and was that dirty green colour that may be suitable for an army tent, but not so good for the home) and got it stripped and powder-coated in my favoured Signal Yellow. I may be right in thinking it cost about 40 for the base and platter, with the relevant screw threads and holes arranged to be masked up. I think they welded up some extraneous holes for an ex-tonearm as well. I put the labels and plates back on afterwards.

Mike Phelan 22nd Dec 2019 9:04 am

Re: Re-spraying record decks.
 
I would completely remove the old paint and start with a can of primer.

alanworland 22nd Dec 2019 9:27 am

Re: Re-spraying record decks.
 
Agree, completely strip, if some has come off the rest is probably the same - about to.
I would use an etch primer first.

Alan

Radio Wrangler 22nd Dec 2019 10:02 am

Re: Re-spraying record decks.
 
Quote:

Originally Posted by Michael Maurice (Post 1201139)
What paint would I use? I usually buy car paint from say Halfords. Can I spray straight onto the old paint, or do I need to strip off the old paint before I spray?

Spraying shows up any unevenness of the underlying thing. It takes care and sensitive finger tips to feel if something is smooth enough to be worth spraying.

For something the size of a turntable chassis, I wouldn't mess around, I'd want all the paint off. I have a bead blast gun and a compressor in the garage. This makes it easy, removes rust and leaves an excellent surface ready for etch primer (available in aerosols). The job of the etch primer is just to grip the metal, after a single coat, apply a coat of ordinary primer or 'high build' primer. If you see/feel unevenness, you can rub this to flatten it. Spray on another coat if you go through. Only when you are really really happy with the undercoat is it time for the colour coat. The smoothness of the preparation is what sets the quality of the finished job. Depending on the sort of paint you choose for the colour, you may need to apply a clear lacquer coat on top.

Holts used to do a grey/silver metallic aerosol called 'Steel Wheels' that I've used as a good finish for amateur radio gear, looking like the finish Yaesu and Trio used. The finish isn't high gloss, and would look right at home on the chassis of a Garrard autochanger of the sixties onwards.

Avoid cellulose paint. It is VERY fussy about what paints are under it and will bubble up or wrinkle if there are even slight traces of some other chemistries remaining. Commercially, you are no longer allowed to use it, except for repairing things already in such paint. Repair aerosols from car accessory shops are mostly acrylic, which behaves better and is quite tolerant.

I have Land Rover 'Bonatti Grey' in stock which is also a mid grey which would look suitable, but this is in a non-aerosol paint system that needs a clear overcoat. I'll be spraying some next year when the weather clears up, so the guns will have all the right stuff in them to do one for you.

David

Scimitar 22nd Dec 2019 10:03 am

Re: Re-spraying record decks.
 
Nearly right advice! Things have moved on a great deal in paint technology. The first step is to completely strip the deck back to clean, shiny metal. Blasting is a good technique but flatting with 120 grit dry is good if you have the elbow grease. You can get it powder coated but I don't feel that will be a 'domestic' enough finish personally.

Next stage is to clean it thoroughly. Soap and water allowed to dry after rinsing, followed by panel wipe.

A coat or two of a decent epoxy primer comes next. There are many on the market but my favourite is Lechler 29107. That is a two part primer but does not contain isocyanates so nothing special in the way of PPE required.

Once that has gone off (24 hours) flat it back to 400 grit dry and then you can paint it with whatever floats your boat. For the best possible quality, take it round to a friendly bodyshop for 2K paint finishing. Otherwise a DECENT quality aerosol from a car bodyshop supplier will have you very pleased with the result.

Radio Wrangler 22nd Dec 2019 3:48 pm

Re: Re-spraying record decks.
 
Michael is probably going to be limited to aerosols, so I reckoned that ruled out epoxies.

I don't bother buying 800 and 1200 grit, I've plenty of worn-down 400 which I use with soap. For Michael, without any prior stuff to hand, he'll need something a bit finer than 400 for anything which may be critically viewed.

That Land Rover grey I use is 2K, by the way.

I certainly agree with the advice about aerosols from good bodyshop suppliers rather than consumer brands. I use Woodauto in Huddersfield, but that's somewhat out of Michael's roaming area. There must be equivalents around London.

David

stevehertz 22nd Dec 2019 6:44 pm

Re: Re-spraying record decks.
 
My experiences with using body shops for things other than cars have always been bad. I once spent hours cleaning off and preparing a high end electric guitar (PRS) and got it sprayed by a local body shop. The finish never fully hardened off, and the sound of the guitar was dull and lifeless. Car sprayers tend to apply too much paint to domestic objects giving them a very obvious 'resprayed', 'thick' look. Just my experience.

G6Tanuki 22nd Dec 2019 6:57 pm

Re: Re-spraying record decks.
 
Getting a good finish is all about preparation.

I'd seek to remove *all* of the existing paint, thoroughly abrade the underlying metal to remove any signs of oxidation or 'spider-web tracks', then go for an acid-etch primer - "U-Pol acid #8" in a rattle-can is available from the likes of Halfords.

Then the top-coat is up to you - in the past I've had decent success with "Plasti-Kote" acrylic rattle-cans - the thing here is not to over-spray in a single coat (or you will get runs) and then to leave the painted object somewhere warm for a couple of weeks for the paint to properly harden. If you handle too soon, or try to reassemble things, you can easily tear or indent the surface of the paint-film.

Michael Maurice 22nd Dec 2019 10:48 pm

Re: Re-spraying record decks.
 
Thank you all for your inputs (excuse the pun) Not this time, but I will try it soon on a deck that requires refurbishing.

Scimitar 23rd Dec 2019 7:45 am

Re: Re-spraying record decks.
 
Quote:

Originally Posted by Radio Wrangler (Post 1201319)

Michael is probably going to be limited to aerosols, so I reckoned that ruled out epoxies.

The Lechler can be brushed or rollered. Just takes more flatting of course, but worth it because it outperforms any other primer on the market, on all substrates, even difficult ones like aluminium and plastics.
It is also totally inert and waterproof when cured so you can use anything you like over the top with no risk of reactions.

Quote:

Originally Posted by Radio Wrangler (Post 1201319)
I don't bother buying 800 and 1200 grit, I've plenty of worn-down 400 which I use with soap. For Michael, without any prior stuff to hand, he'll need something a bit finer than 400 for anything which may be critically viewed.

It depends what is going over the top of course. For a thin material like acrylic, then possibly finer. For metallics then 800 is the figure to aim for, all preferably done dry. 400 dry generally will suit solid 2k but even then I tend to go 800 for everything.

Quote:

Originally Posted by Radio Wrangler (Post 1201319)
That Land Rover grey I use is 2K, by the way.

2k is good stuff if you have the correct PPE of course. I would have suggested basecoat and lacquer if he did, a nice cherry red metallic maybe?

Quote:

Originally Posted by Radio Wrangler (Post 1201319)
I certainly agree with the advice about aerosols from good bodyshop suppliers rather than consumer brands. I use Woodauto in Huddersfield, but that's somewhat out of Michael's roaming area. There must be equivalents around London.

Just for his information, the reason for that recommendation is the spray nozzle and pressurisation quality. They give a nice consistent pattern which can make all the difference. Also they can be mixed to any colour that can be imagined.

GrimJosef 23rd Dec 2019 10:55 am

Re: Re-spraying record decks.
 
As well as having very versatile colour mixing capabilities, paint specialists often have optical scanners these days which will get a close (depending on how carefully they're maintained and operated) match to the colour of existing paintwork. They can also add various amounts of matting agent to adjust the glossiness of the finish.

Cheers,

GJ

joebog1 23rd Dec 2019 10:21 pm

Re: Re-spraying record decks.
 
A small trick with spray cans!! Put them in a bucket of hot water before spraying.
This does several things,
1. Thins the paint a little so smaller atomisation.
2. Increases the pressure inside the can, so again better atomisation.
3. Allows thinner coats to be applied.
All the above make for "no orange peel" which is horrible to look at on something we look at very closely.
Spray cans ( good quality ones) are capable of excellent results.

A reasonable time in the hot water is advised!! Too long, or too hot and it may burst
( although I have never seen that happen ).
This was shown to me by an automotive panel beater/spray painter.

Joe

Scimitar 24th Dec 2019 8:37 am

Re: Re-spraying record decks.
 
Quote:

Originally Posted by joebog1 (Post 1201681)
A small trick with spray cans!! Put them in a bucket of hot water before spraying.

Yes true, however the panel needs to be at a similar temperature. Not so much of an issue down under I suppose! ;D

Michael Maurice 24th Dec 2019 2:57 pm

Re: Re-spraying record decks.
 
Quote:

Originally Posted by Scimitar (Post 1201728)

Yes true, however the panel needs to be at a similar temperature. Not so much of an issue down under I suppose! ;D

You can always use an oven to heat it up to 20 -30 degrees.

Radio Wrangler 24th Dec 2019 3:46 pm

Re: Re-spraying record decks.
 
You don't want the panel too hot if you want a gloss finish, you want the paint to settle and smooth out by surface tension before the solvent flashes off.

David

G6Tanuki 24th Dec 2019 5:55 pm

Re: Re-spraying record decks.
 
Also important if spraying with rattle-cans is ambient humidity. As soon as the paint emerges from the spray-nozzle the solvents (and some dissolved propellant) want to evaporate - which involves grabbing heat from the environment, and so the individual paint-droplets cool and act as foci for condensation of any moisture in the surrounding air. If moisture condenses on the paint-droplets, or the cooling effect causes air-moisture to condense and then be carried onto the workpiece along with the paint-droplets - the finished result can include millions of tiny moisture-inclusions which give a matt surface when you wanted a shine.

stevehertz 24th Dec 2019 6:17 pm

Re: Re-spraying record decks.
 
Quote:

Originally Posted by joebog1 (Post 1201681)
A small trick with spray cans!! Put them in a bucket of hot water before spraying.
This does several things,
1. Thins the paint a little so smaller atomisation.
2. Increases the pressure inside the can, so again better atomisation.
3. Allows thinner coats to be applied.
All the above make for "no orange peel" which is horrible to look at on something we look at very closely.
Spray cans ( good quality ones) are capable of excellent results.

A reasonable time in the hot water is advised!! Too long, or too hot and it may burst
( although I have never seen that happen ).
This was shown to me by an automotive panel beater/spray painter.

Joe

I just clicked the 'like' button.

stevehertz 24th Dec 2019 6:19 pm

Re: Re-spraying record decks.
 
Quote:

Originally Posted by G6Tanuki (Post 1201854)
Also important if spraying with rattle-cans is ambient humidity. As soon as the paint emerges from the spray-nozzle the solvents (and some dissolved propellant) want to evaporate - which involves grabbing heat from the environment, and so the individual paint-droplets cool and act as foci for condensation of any moisture in the surrounding air. If moisture condenses on the paint-droplets, or the cooling effect causes air-moisture to condense and then be carried onto the workpiece along with the paint-droplets - the finished result can include millions of tiny moisture-inclusions which give a matt surface when you wanted a shine.

Ok, so you want the ambient humidity to be...?

G6Tanuki 24th Dec 2019 7:00 pm

Re: Re-spraying record decks.
 
Ambient humidity - ideally somewhere below 50%, that way it becomes a small-to-insignificant effect. This is why professionals use air-conditioned spray-booths.

Normal UK ambient humidity is more iin the 65-90% range!


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