109 replies to this topic

[Daz1968]

you can spray UPOL P88 without thinner added.

[skoughi]

That's what I'm using but the needle and cap I have is on the small side so it requires some thinner in it. It's my own fault for not getting a 2mm one, something which I think I'm going to sort this afternoon!! It's the sheer amount of thinner in with the primer that's causing my problems but saying that it's only small spots here and there that's flaring up. A larger needle/cap and less thinner and everything should be ok but would still use premium thinner if it's available .

[skoughi]

What set up do you use daz to be able to spray unthinned P88?

[Daz1968]

I have a kestral primer gun with 2.0 set up, pressure about 45psi when I have used upol p88 it won't be as flat sprayed neat but it sands no problem. I am confused by reactions though, try lighter coats as sometimes it can react with itself when a lot of thinner is present, I have had problems with upol high 8 aerosol before and it was down to applying to thick a coat and applying second coat before first has flashed properly.

[skoughi]

I've been and ordered a 2mm needle and cap for my gravity gun this afternoon, should be a bit better flow rate but I would think I'll need some sort of thinner but I'll see how I get on. I've stripped the old paint off the clubman but there's still little bits here and there in the corners etc. I went out this afternoon and sanded off the couple of little spots where I got a reaction and on all of them there was a little bit of old paint, this could be anything from oil paint to synthetic or even celly thats softening with the standard thinners I'm using. I sanded off the reactions, heated up the area with a hot air gun and dusted on a few light coats with an aerosol tin of primer drying it quickly with the hot air gun between coats and it seems on the whole ok. I've had reactions like the reason you say, not waiting long enough between coats and getting paint lifting in a panel corner where the previous coat hasn't properly flashed off. I find also thinner coats nearly dusting on the first couple helps to reduce reactions over filler etc then heavier coats after that. I'm getting plenty of warmth in the garage as I swith on a space heater for five mins before each coat so its no less warm than a booth would be while painting. Hopefully the primer I applied last night should be enough to flat out the remaining marks and I'll only need to do spot priming before colour, if not then I have the 2mm set up to try and see if I can get better flow from my gun.

[kezzkitkat]

interesting my personal experience on a 2mm  gun set up is that its far to heavy regardless of viscosity i personal like between a 1.6 to a 1.8.

ive seen some painters have problems with reaction from moisture from the body filler 

[Daz1968]

Here is tds it states ready for use but upto 100% thinner can be added! I have used it without thinning but also have thinned it in other applications! the tds also states gun as 1.6 to 2.0mm,

http://www.u-pol.co..../P88-TDS-EN.pdf

To be honest though I have moved over to using epoxy and 2k primers as you get a much better build and are easier to work with and never really have reaction issues.

[skoughi]

I've got a 1.7mm cap/needle just now and it's putting the stuff on but I'd like to have less thinner so I'm hoping the slightly larger size can help with this, the moisture could be a problem as well. I had a few areas of filler on the roof that had been primed previously and I'd rubbed back so the filler and surrounding metal was exposed. This had no water on it for over a day with the garage warmed up, however with a light dust of etch on the metal and a half hour wait I got a reaction on the filler edges when I shot on the first coat of primer. I left it another half hour, rubbed it flat again, gave it a few light coats of primer and it was fine. So there could have been a little moisture involved with that issue.

Edited by skoughi, 17 October 2014 - 07:53 PM.

[skoughi]

I thought about using 2k primer but as I have a lot of filler which I'm not too happy about I felt I would be priming and rubbing down a few times, but with hindsight I think I should've just gone for the 2k as that would've probably given me less hassle. I live in a residential area so was wanting to keep the use of 2k paint to a minimum.

[Daz1968]

Epoxy is a very good dealer and isn't as dangerous as 2k it only needs a filter mask

[germini30]

Alot of people have been saying to go for 2k to me. The only thing I am concerned about is the health risks. Cellulose is alot safer for me.

[Daz1968]

I wouldn't use 2k high build without airfed mask and filtered extraction on garage, many risk it but I don't think its worth it. Epoxy on the other hand only needs standard mask and is very stable to paint over once cured.

[Shifty]

Mipa do a nice 1k high build and etch primer. You can even brush it on rather than spray it as well.

[germini30]

Ok. Can I apply barcoat tomorrow night and then prime tuesday night or does the primer have to go on the barcoat quicker

[167ade]

Ok. Can I apply barcoat tomorrow night and then prime tuesday night or does the primer have to go on the barcoat quicker

only apply 1 coat of barcoat no more let it dry fully generally 1hr dry time but that will depend on temp if it on the cool side leave it longer i always prime as soon as its dry enough if you leave it till the next day you may have adhesion problems but iam not sure of that as i have never left it till the next day