Which water based undercoat?

[Michaelsf90]

Pricing up water based undercoat. I'm using dulux water based gloss. But I realised it's all in the undercoat. The gloss just adds a shine. I was using johnstones aqua water based undercoat which a painter friend of mine give me. I've now ran out. I've been doing two coats of undercoat. Just wondering with pricing it up I can get crown undercoat for £16 whereas dulux is £30. Just after a professional opinion is the dulux worth it. So long it'll take one coat whereas the crown will take 3 coats? Just don't see the point in paying double if I still need to put two coats on with both brands of paint. I've realised the 2.5 litres of gloss is barely going to get used whereas I seem to be getting through undercoat rapidly

 

[johnny2007]

I use layland undercoat.
It's a bit more liquid than most water based and gives you a little more time to spread it.
They also do a primer/undercoat version for bare wood and I used it successfully.
IMO spending a lot of money in undercoat is not worth it.
They all do the same thing.

 

[opps]

I too use the Leyland Trade acrylic primer/undercoat, however I use it because it is easy to sand back. I tend to pretty much sand it back completely, given how cheap it is (about £12 per 2.5L). All water based primers will result in wood grain swelling. I let it swell and then sand it flat.

That said, I then use oil based paints over them so the swelling/sand back isn't an issue.

The last time that a customer specified Johnstone aqua eggshell, I was painting MDF doors. I ended up having to apply 4 coats plus WB primer. Were I using oil based eggshell, it would have been WB primer and 2 two coats.

I have swerved having to use waterbased gloss thus far.

If you want to minimise grain swell and maximise colour obliteration, you can use OB based UC but you need to wait a few days to let it cure. If you don't you may end up with fisheyes in the waterbased finish coats.