Refinishing paint that has gone tacky

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Bonefishblues
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Refinishing paint that has gone tacky

Post by Bonefishblues »

I've got a pair of speakers I'll be selling in the not too distant future. They're on bespoke stands, made with the speakers. So far so good, but there's a peculiar thing which afflicts these from time to time in that the black paint finish goes slightly tacky. It's only happened to one half of one stand, oddly. I want to re-finish the stand and I think a good quality blackboard paint will match nicely.

My question is, how to remove the tacky paint such that I can re-paint? You will see the speaker and stand below. Obviously I will mask the poplar wood finish very carefully, but what's the best method/product to take the tacky finish off would you say?

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Stoneybatter
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Re: Refinishing paint that has gone tacky

Post by Stoneybatter »

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Last edited by Stoneybatter on 20 Aug 2022, 1:31pm, edited 1 time in total.
Bonefishblues
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Re: Refinishing paint that has gone tacky

Post by Bonefishblues »

Nobody knows, and Mr Zingali hasn't issued any advice I'm afraid, hence my query here. Is there a hierarchy of strippers I can try, as it were. Every other surface on the speakers is unaffected - it's very odd, but it's a thing with this gen.
Jdsk
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Re: Refinishing paint that has gone tacky

Post by Jdsk »

Stoneybatter wrote: 8 Aug 2022, 10:25am ...
As far as paint removers go, options are fewer than they used to be. You simply can't buy effective paint remover any more. It's all been reformulated to comply with some daft, arbitrary regulations, probably emanating from the EU. God be with the days of proper Nitromors, which would remove stove enamel in seconds.
...
The active ingredient in the old formulation of Nitromors was dichloromethane. You can buy this.

NB safety precautions.

Jonathan
Jdsk
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Re: Refinishing paint that has gone tacky

Post by Jdsk »

Bonefishblues wrote: 8 Aug 2022, 10:29am Nobody knows, and Mr Zingali hasn't issued any advice I'm afraid, hence my query here. Is there a hierarchy of strippers I can try, as it were. Every other surface on the speakers is unaffected - it's very odd, but it's a thing with this gen.
There's a general purpose hierarchy of solvents: isopropanol, petrol-like, acetone in order of aggression.

But I have no idea why your paint is going tacky.

Or whether mechanical attack would be preferable.

Jonathan
Nearholmer
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Re: Refinishing paint that has gone tacky

Post by Nearholmer »

Are the black bits metal, as opposed to wood?

If so, and if you can either protect the wood or, better, separate the metal parts from it, then Mister Muscle oven cleaner is a very good paint stripperfor a wide range of paints. Put the parts in a plastic bag, give them a good dose of the cleaner, leave for a couple of hours, then wash off with water. Wear rubber gloves and do it outside in a light breeze to avoid breathing the fumes.

If the black bits are wood, this might be a much more challenging job: the only answer might be sanding back.

Paint on metal can stay or periodically go tacky if the formulation wasn’t right in the first place, or the metal wasn’t properly clean, maybe oily, with the oil interacting with the paint.

Paint on wood can do the same if the wood is resinous.
Bonefishblues
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Re: Refinishing paint that has gone tacky

Post by Bonefishblues »

Nearholmer wrote: 8 Aug 2022, 10:34am
If the black bits are wood, this might be a much more challenging job: the only answer might be sanding back.

Paint on wood can do the same if the wood is resinous.
As best I am aware it's a very high density MDF - it's certainly a composite, unlike the poplar insert next to it I really don't want to be sanding if I can avoid it, not least because MDF.
Bonefishblues
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Re: Refinishing paint that has gone tacky

Post by Bonefishblues »

Jdsk wrote: 8 Aug 2022, 10:33am
There's a general purpose hierarchy of solvents: isopropanol, petrol-like, acetone in order of aggression.

Jonathan
I will have a very limited dabble with some ipa I think, by way of test.
tim-b
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Re: Refinishing paint that has gone tacky

Post by tim-b »

Cabinet scraper or plane iron. Lightly sand and then seal with Zinsers BIN or MDF sealant if you get that deep
~~~~¯\(ツ)/¯~~~~
Bonefishblues
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Re: Refinishing paint that has gone tacky

Post by Bonefishblues »

Oh and just for giggles it has 6 wee grooves running top to bottom, echoing the grooves on the speaker cabinet.
Bonefishblues
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Re: Refinishing paint that has gone tacky

Post by Bonefishblues »

Stoneybatter wrote: 8 Aug 2022, 10:25am Incidentally, what sort of drivers are in the cabinets?
8" horns below and 210mm mid/bass above.

Video here showing greater detail:

https://youtu.be/O_lRkdYZ2dk
Bonefishblues
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Re: Refinishing paint that has gone tacky

Post by Bonefishblues »

IPA is taking it off very well indeed, but it's clear that the finish is very deeply applied, so I think it might be scraper to start, and then IPA to finish.
Bonefishblues
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Location: Near Bicester Oxon

Re: Refinishing paint that has gone tacky

Post by Bonefishblues »

By way of update, a scraper is the way forward as the paint finish is really deep, so slow and patient progress - but enough about me :D
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