2 replies to this topic

[Jae]

Hi,

I'm about to respray my estate - i've got three guns (1 free pants one, 1 semi pants one and 1 decient - cost me £80 too).. any how..

The car is currently red and will be mondaoo midnight blue - metalic.. I have etch primer, normal primer, the main colour and clear coat..

So my questions are:

How much do I need to sand down the orginal colour? I don't really want to take the shell back to bear metal if I can help it, as I just don't have the time.

I'm assuming the etch primer is just for the new panels I've welded on, or should I cover the whole car in a coat of it?

When spraying, i should do the following?

Etch primer - leave 12 hours - sand with 800, clean car with tac rag
main primer - leave 12 hours - sand with 800?, clean car with tac rag
1st main coat (thin) - now do I sand inbetween main coats?
2nd main coat
3rd main coat
4th main coat with very thinned down pain 70/30?
let dry for 24 hours
do I sand before the clear coat, and with what grade?
1st Clear coat - sand?

urlgh... im getting all confused when to sand.

Also anyone know what primer I need to use on replica sportspack arches (the black rubbery ones?)

thanks.

J

[cooper_shaz]

Hi there

here is a guide for you but you have not said if it is cellulose, 2 pack solid colour or metallic, also no mention of spraying in a booth, or garage etc, but here is a guide that covers most things hopefully.

You do not need to sand down the car to bare metal.

As you are going to respray the whole car in a different colour key the car down with a scotch brite pad or wet and dry 600 will do.

You need to key it down so that there is not a single shiny spec left on the car or the paint will not adhere.

then
Treat the bare metal areas with POR 15 metal ready as this will etch, and zinc coat the panels giving them added protection.

From there it is probably an idea to spray a layer of barcoat as there is a good chance you are going to mave a mix of paint on there.
The barcoat will stop any reactions happening. Do not sand this coat down or rub through it or the protection is gone.

Then etch prime the bare metal / repaired areas, you do not need to etch prime the whole car but you can if you want.

clean the car down with panel wipe to remove any grease, wax, polish residue then tak rag.

Wet and dry the etch primer with 600 and lots of water
then prime the car

Not sure if you are using 2 pack or cellulose here and what your spraying conditions are as this all affects drying time

Typically for cullulose primer a few hours on a warm day will be long enough, but the longer you leave it the better as more solvents evapourate and the paint sinks.


You should not need to sand between each coat of top coat, and if it is a solid colour, ie non metalic you do not need a clear coat
apply your base coats and then if ti is a solid colour you can run down with wet and dry 1000 and then apply final coat, or flat and polish after the final coat as this will remove any imperfections if done correctly (see the how to get that shine after painting guide)
click for the guide

use a plastic primer for the arches if they are the hard ones (Normal sportspack) then normal primer and paint is fine, if they are very flexible then you need a plasticiser added to the paint (speak to the paint shop)

hope this helps

cheers
Shaz

[anger management]

Hi,

I'm about to respray my estate - i've got three guns (1 free pants one, 1 semi pants one and 1 decient - cost me £80 too).. any how..

The car is currently red and will be mondaoo midnight blue - metalic.. I have etch primer, normal primer, the main colour and clear coat..

So my questions are:

How much do I need to sand down the orginal colour? I don't really want to take the shell back to bear metal if I can help it, as I just don't have the time.

I'm assuming the etch primer is just for the new panels I've welded on, or should I cover the whole car in a coat of it?

When spraying, i should do the following?

Etch primer - leave 12 hours - sand with 800, clean car with tac rag
main primer - leave 12 hours - sand with 800?, clean car with tac rag
1st main coat (thin) - now do I sand inbetween main coats?
2nd main coat
3rd main coat
4th main coat with very thinned down pain 70/30?
let dry for 24 hours
do I sand before the clear coat, and with what grade?
1st Clear coat - sand?

urlgh... im getting all confused when to sand.

Also anyone know what primer I need to use on replica sportspack arches (the black rubbery ones?)

thanks.

J

Mate.........you only need to sand the exsisting paint on the car for a key, i.e. so as the fresh paint can adhere to panel and does'nt flake off. This is acheived by scaring the surface i.e. flatting with sandpaper or even scotchbrite.
The only time you should really sand to bare metal is if you need to sand (feather-out) a chip,scratch or crazing, but even then, if it sands out (feather-out) before you go through to the metal then theres no need to go any further.
Rust however will have to be scurfed out by means of an angle grinder or shot-blasted, failing that, then you'll have to cut it out and patch it up (you might if your lucky, get away with rust treatment, though i doubt it).
Etch primer though, should only be used on alluminium panels, you can us it though, but i'd say better off with a filler primer as i'm sure you'll have an uneven surface here & there so as you can then sand it down as flat as poss!

When spraying colour, dont sand anything unless you have a huge piece of C**p fly into it, allow every coat a good ten mins to dry and apply each coat over-lapping, first few coats being grip coats, progressing to medium coats with a final coat a double header. If you are spraying celli paint, then allow base colour to fully dry before clear coat, but if your spraying 2-pack, then just allow it to tack-off i.e. 10 to 15 mins depending on room temp etc, before clear coat. Your colour coverage should be good and only need a few coats, but some new 2-packs dont cover that well as the lead has been taken out, so try and apply common sence when spraying for coverage!
If your drying in an oven, then bake off and should be ok to de-mask within 30 mins, if not, then leave to dry 24hrs and even then, be very careful as it will be soft!
By the way..............arches or any plastic's should be primered in plastic primer, preferably flexable.