# Drying paint quickly?



## Franzpan (Mar 2, 2009)

Hi guys, just wondering, how do the likes of mobile alloy wheel repairers get the wheels dried so fast to enable painting in one session?

I've heard of lacquer which can be cured quickly in a uv drier, is this what they all would use?


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## andyrst (Apr 6, 2009)

infra red dryers


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## squiggs (Oct 19, 2009)

It all depends on what paint they're using and what lacquer.
Waterbased paint is air dried by passing warm air across the paint.
Solvent paint is dried using infra-red heaters (they are specialist bits of kit and not the same as you'd use for heating your guests out on the patio on a cool summers evening lol)
Lacquer is again usually infra red but they might use a lacquer that's cured by UV


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## Graeme1 (Dec 9, 2006)

UV is started to be used a lot as it's quick flash off and once you set the reaction going then it's fine. Wheels you won't need to flat and polish so a couple of passes with a uv lamp and there done.


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## mr paint (Jul 11, 2009)

short wave infra red is what you need ... i cure clears in about 15 mins


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## Paintguy (Oct 31, 2005)

I used UV cured lacquer when I was working as a wheel refurber. 

Spray on 1 coat, leave it 3 minutes to flash off, then 3 minutes in the oven and it was rock hard.


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## Franzpan (Mar 2, 2009)

mr paint said:


> short wave infra red is what you need ... i cure clears in about 15 mins


Is fifteen minutes about the norm? Or was that some sort of fast drying clear?



Paintguy said:


> I used UV cured lacquer when I was working as a wheel refurber.
> 
> Spray on 1 coat, leave it 3 minutes to flash off, then 3 minutes in the oven and it was rock hard.


Three minutes! Now that is fast!


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## squiggs (Oct 19, 2009)

Franzpan said:


> Is fifteen minutes about the norm? Or was that some sort of fast drying clear?
> 
> Three minutes! Now that is fast!


As far as I'm aware most clears are about a 30 min bake @ 60 degs C. 
In an oven it will take some time for wheels/panels to get up to temp - a UV lamp bakes from the inside out and can heat up a small area significantly quicker than an oven.
Wheels do present a bit of a problem when trying to dry a 'normal' lacquer with UV lamps as wheels are designed to disperse heat and do this very effectively. This can be demonstrated by sticking 3 UV lamps up close to a wheel - if the tyre's still on it will start smoking long before the wheel gets to 60 degs C.
With different additives you can speed a lacquer up, but then there are those that say that it's not as robust - and apparently some people on the jury aren't convinced that UV lacquers are as robust as a 'normal' lacquer
There are also a few very quick drying (5 mins or so under infra-red) lacquers aimed at the smart repair industry. Feed back from those that have tried it has suggested it as being "not as robust as 'normal' lacquer". As such I've yet to know a reputable smart repairer to use such a lacquer as his main weapon of choice.


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## Andyb0127 (Jan 16, 2011)

Our ovens used to be set at 35 mins @ 75 deg C, reason for that was takes five mins to get upto temperature, as for setting temp at 75 that was because that would make the panel temp 60deg C giving a bake time stated by squiggs.

We use max Meyer hs laquer on our wheels, then put in a wheel oven for twenty mins. But our smart repairs we use a laquer which is infa-red for ten mins then polished. But as squiggs said there's so many types of laquers and acceleraters its like a minefield. But to give you an idea bradleys do a laquer called Kristal time, supposedly a hs laquer which will infa-red in five mins and be fully cured. Trouble is with these faster drying laquers that alot will look fine when done, than slowly drop back and loose there gloss level.


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## Paintguy (Oct 31, 2005)

squiggs said:


> In an oven it will take some time for wheels/panels to get up to temp - a UV lamp bakes from the inside out and can heat up a small area significantly quicker than an oven.
> Wheels do present a bit of a problem when trying to dry a 'normal' lacquer with UV lamps as wheels are designed to disperse heat and do this very effectively. This can be demonstrated by sticking 3 UV lamps up close to a wheel - if the tyre's still on it will start smoking long before the wheel gets to 60 degs C.


Are you sure you mean UV and not infra red? I've never heard of any UV product that uses heat to cure. Mine used to be stone cold when finished, as they use a completely different technology with the light kicking off the polymerisation, rather than with regular 2K products where you can use accelerators or heat to speed up the process.

As for the really quick "regular" clears you mention, I tried one by Sherwin Williams and it was extremely fast, both to apply and cure. You hammer it on as thickly as possible in one go, then even at room temperature it was touch dry in 5 minutes, polishable after 30. Put some heat on it and it was crazy fast.

I spoke with a few guys in the States though (where SW is a much more widely used brand) and there were worries about its durability, same as what you have heard. It could nip up and lose it's gloss after a few weeks which isn't great.

After that I teamed up with the technical guys at DeBeer to find a solution for ourselves. What we eventually hit upon was using our regular clear (DeBeer 8-214 Scratch Resistant) with a few percent of a taping additive from their commercial line. This additive was designed for using when painting lorries etc with multiple colours in one session. The resin technology was pretty similar between the two systems so we thought we'd give it a try and it works perfectly.

So I can use my normal clear for everything, but if we get a small job like a bumper cover or single panel I can add in 3% of this stuff and it'll bake in 10 minutes rather than 30, saving us a huge amount on gas. The finished product is much harder to polish so I don't use it on any large or flat panels that might get a few dust nibs in them, but it's perfect for small jobs that you aren't going to polish. And unlike regular accelerators like U-Pol Rocket etc it doesn't lose any gloss at all, either straight out of the oven or long term.

Ramble over....


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## squiggs (Oct 19, 2009)

I've only read the first sentence - Opps!
Did I make another mistake? Nope ... phew!

Now I'm not having a Knock - I'm interested ...
I polish every job I do - when would you do a job that you wouldn't polish - would they be trims, mirror cases etc?


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## Paintguy (Oct 31, 2005)

I guess the best way to describe it is that we only polish what we have to, when something has gone wrong with the painting.

So if there's a run or a dry spot (very rare), if there's too much texture (like over a coarse silver where the clear hasn't flowed properly over the large flakes), fish eyes (we have a bit of a silicon problem here), or the most common - dust & dirt in the job.

So on the whole every flat panel (like roofs & bonnets) tends to need polishing as they attract the most dust, but most other things don't need it, or at least only a bit of localised work to remove any dust nibs.


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