Hi there, im in need of some advice on spraying my mini, its knda gone wrong and wondered if anyone knew of any uk based spraying forums or simular i could ask some questions on, unless anyone on here is able to help please let me know as im really annoyed with myself lol Thanks in advance Greg

What do you need to know?

Ive sprayed 5 or six cars in the past (10+ years ago), there are some very experienced sprayers on here too, drop the question in & we will see if we can help

Well i put the colour on last night and i noticed that there were little crazings or spider web patterns appearing, now this has happend to me before using the same paints, but put it down to where i had sanded through the primer but this time i made sure i didnt sand through and it has still happend. So im not sure if it was to much paint or to cold or to little flash time inbetween coats. What im not sure of is how best to get over this so far i have sanded the areas down with 800 grit primed the areas again where i have rubbed through to bare metal but not sure wether to sand the whole panel down with 800grit to even up the surface?

also when it comes to spraying should i just spray the affected areas for a couple of coats and then the whole panel as the paint is very thin im using a ratio of 1:1 but thinking of changing to 2:1 as i feel its the thinners causing the crazing?? or should i keep applying full coats over the whole panel until the patch is gone?

Sorry for the long post forgot to mention its also metallic blue
Thanks again

It sounds like the thinners in the paint is reacting with the primer. what paint and primer are you using.
You should always use etch primer on bare metal, just a dust coat.

[Edited on 29/3/11 by deltron63]

You need to talk to Mark Allanson, member on here.

2k primers and im not sure what the actual colour is possibly cellulose but does say 2K on the can but no hardner is addded just thinners then i will be lacquering with 2k as well

edited to add i have etch primed any bare metal first, worst part is i know someone that is spraying and he hasnt etch primed or degreased and hasnt had any of these problems which makes it all the more annoying lol

[Edited on 29/3/11 by corrado vr6]

http://www.mig-welding.co.uk/spray-painting.htm

It shouldn't react with 2k primer. Does it say what the mixing ratio is. Like you say some are 1:1 others 2:1.
If it celly then you have to put lighter coats but more of them. 2k 1 dust coat then as many as it needs to cover the primer.
You can try to dry the first coat with a hot air gun, but let the others flash off between coats. ( trapped solvents will blister later on ).
It's a shame you live so far away or i'd come around and do it for you ( 25 yrs panel beater/ sprayer )

I was told when i bought the paint that it was 1:1 but from reading posts on random forums people seem to use a thicker ratio so was thinking using 2:1 and hopefully with the less thinner i wont get the crazing.
I think it is celly and possibly the coats i put on were to thick but i didnt get any runs which is odd.
I know that i shouldnt spray lacquer if its raining but is it the same for spraying celly base coat as hoping to sort this tomorrow but think its meant to rain just means i wont be able to lacquer unless im lucky to get the lacquer on tomorrow as well.

I wished this morning someone would sort it for me lol but i guess you only learn from these things i must have calmed down since this morning as i was well pissed off with my efforts, the beer must be kicking in now!!

you can wipe the celly off without hurting the 2k to much with thinners. Celly " blooms" if painted in cold/ damp conditions.
Try it with the hot air gun between coats.

Not too experienced on 2k but when I spray cellulose I always use a viscosity cup so you get the correct ratio of paint/thinners.
Usually 20-25 seconds from memory. Try the paint merchant where you got the materials they are usually best for advice.

I've also found that grazing or cracks in the paint just seem to keep coming back no matter how many layers you spray on. In the past I have just waited for the paint to dry properly and used a touch up pen to fill any, then 1500 wet sanded to blend it smooth and T-cutted to polish.

the fact it says 2K on the can worries me.
You really need to find out what paint it is, celly, basecoat or 2K.

I know I tried some paint (from a coffee jar, left in he boot of a car I bought) that I assumed was touch-in paint. So a used it to touch up a welded patch. That crazed badly, turned out to be 2K paint, I didn't use any hardener. It also stayed "soft" and went dull.

So how do people think i should go about spraying the areas? respray the affected areas lightly a few times then the whole panel a few times or do the whole panel each time / whole body until the affected areas are coloured in? Thanks again and i will phone the paint suppliers tomorrow to find out exactly what the base coat is i dont think its 2k as the sticker on the tin is justa sticker with 2k on it which the use to write the colour of whats in the tin so the 2k is just a random sticker used for this purpose

edited to say unless the 2k stands for 2 stage meaning basecoat then lacquer?

[Edited on 29/3/11 by corrado vr6]

As far as I know they have to label it correctly for H&S reasons, so if it's labelled with 2K it's probably 2K.