Does the requirement to sand between gloss coats apply to water-based quick-dry gloss

Cinquestelle

I painted a door last night using Dulux Quick-dry gloss for wood and metal, and it clearly needs a second coat to obliterate the colour underneath.

I have always sanded between coats of oil-based gloss when needed, but does the requirement to sand between gloss coats apply to the water-based quick-dry variety?

I tried ringing Dulux Customer Services - closed at 12.30.

keystone

Cinquestelle wrote: »

I painted a door last night using Dulux Quick-dry gloss for wood and metal, and it clearly needs a second coat to obliterate the colour underneath.

You shouldn't use a finishing product for preparation IMO.

I have always sanded between coats of oil-based gloss when needed, but does the requirement to sand between gloss coats apply to the water-based quick-dry variety?

I don't recollect it ever being a requirement but if you think about why you would abrade between coats then you will have your answer. It's nothing to do with the type of paint either - by way of a small clue.:D

Cheers

abankerbutnotafatcat

I think you sand so that the new coat adheres to the previous coat. I'm a diy-er, not a tradesperson like Keystone but I've wondered about this myself and I think there's a window (or door!! Haha) of opportunity in which to apply subsequent coats of paint when they will adhere and that window will depend on how long the paint takes to dry. I thought it said on the tin but I tend to do the second coat next day and haven't had any issues with various different types of paint. In the case of a strong colour change, as KS says, an undercoat will prob give the best result.

jcb208

You can try to sand but water based tend to be rubbery when sanded and quite hard so just a light sand to de nib will do

Cinquestelle

abankerbutnotafatcat wrote: »

I think you sand so that the new coat adheres to the previous coat. I'm a diy-er, not a tradesperson like Keystone but I've wondered about this myself and I think there's a window (or door!! Haha) of opportunity in which to apply subsequent coats of paint when they will adhere and that window will depend on how long the paint takes to dry. I thought it said on the tin but I tend to do the second coat next day and haven't had any issues with various different types of paint. In the case of a strong colour change, as KS says, an undercoat will prob give the best result.

That's right, for adherence. Dulux very clearly advises sanding down between coats gloss unless you recoat within a day or so. I know this for a fact since I have been given this guidance from them! But this advice was given in relation to oil-based gloss. However, as stated in the posting, I am using the water-based type which, as it is a different product, may mean the same advice is not necessarily appropriate. I appreciate your experience with other types of paint not leading to any issues abankerbutnotafatcat.

keystone

Cinquestelle wrote: »

You don't recollect it ever being a requirement. Really?

Yes really!

On 11-09-2011 I responded to your question "How long between coats of gloss?" - where you asked what is the maximum amount of time you can leave between coats before sanding to obtain a key for the second coat to adhere.

Not my thread, not my question. Anyway if you know all the answers why are you asking now?

Cheers

Cinquestelle

keystone wrote: »

Yes really!

Not my thread, not my question. Anyway if you know all the answers why are you asking now?

Cheers

Apologies. That assertion was incorrect and I have withdrawn it. With regard to knowing all the answers, I would have to disagree with you. My awareness relates to oil based paints and how they behave, not to water-based paints which is the sole object my quest for further clarification!

keystone

Cinquestelle wrote: »

Apologies. That assertion was incorrect and I have withdrawn it.

S'OK. I wasn't offended. Gladly accepted.

With regard to knowing all the answers, I would have to disagree with you.

that remark was only stimulated by your previous post and in the light of your withdrawal I do likewise with similar sentiments.

My awareness relates to oil based paints and how they behave, not to water-based paints which is the sole object my quest for further clarification!

There are two reasons to lightly (preferably with wet and dry and water) abrade before applying a second coat both of which have been already highlighted. Light abrasion is all that is required with a very fine grade paper and not scouring it to death with 60 grade stuff.

The first reason (as you are aware) is to provide a key. The manufacturers advice is that it is not required if you recoat withi x hours is because the first coat is nowhere near cured by the time that the second is applied so that a key isn't needed as there is sufficient interaction between the two paint films. However, as another poster has already pointed out, if you have nibs and dust contamination you won't get a smooth surface without first abrading it. So my preference is to let it cure, rub down with wet and dry, clean with tack cloth then apply second topcoat. It doesn't matter if its spirit based or waterbased the same principles apply. I always rubdown between all coats irrespective.

To the poster that suggested that waterbased is too soft to rubdown I would suggest that firstly you haven't let it cure properly and secondly you've applied it far too thickly in the first place.

Cheers

Cinquestelle

Keystone, you are a gentleman. Thank you also for the quality and fullness of the reply; it is extremely helpful.

Star23

Cinquestelle wrote: »

I painted a door last night using Dulux Quick-dry gloss for wood and metal, and it clearly needs a second coat to obliterate the colour underneath.

I have always sanded between coats of oil-based gloss when needed, but does the requirement to sand between gloss coats apply to the water-based quick-dry variety?

I tried ringing Dulux Customer Services - closed at 12.30.

Yes oilmbased and watrre based needs a key .
Watre based and ol based needs two coats and water based has a very different application technique