Correct way to spray a door or panel

[Robin]

I asked a question about paint removal in a previous thread and this led to some answers about spraying so I just wanted to bring this together in a new thread - hope that's OK. Thanks to everyone who gave advice and so my understanding is as follows with regards to spraying a replacement door for my Mk2 Vitesse (I'm planning on using cellulose aerosols)

 

1. Sand existing paint back to bare metal using poly strip sanding discs attached to either a drill or angle grinder.

2. Fill any imperfections and sand 

3. Spay a few coats of etch primer. Does this need sanding between coats?

4. Spray a couple of coats of High Build Primer and flatten back. Do I use 600 wet and dry for this?

5. Spay thin coats of cellulose top coat to gradually build up the layers - about 5 coats in total.  Do I flatten between coats using 600 wet and dry?

6. Apply final top coat and leave to dry. How long for and does anything else need to happen to the final coat or is that it?

 

Have I understood this correctly or am I missing something?

 

Many thanks again

 

 

Robin

 

[Guest]

Hello Robin.

 

Have a look at this link http://www.mig-welding.co.uk/ under the paint section.

 

It's very informative not just on paint etc.

 

Good luck.

 

Richard.

[Clive]

Etch prime the bare metal, a couple of light coats will be fine. Ideally done straight after paint removal and filling.

Note on sanding filler, I have had success using abrasives on long pieces of (straight) wood. On a door which is flat that is important.

 

A good high build primer can go on in double coats, flatting between pairs of coats. 600 initially. Then once you think it is OK, spray a guide coat of paint (black usually used but whatever you have to hand) and flat. Thus will reveal high and low spots to remedy. Then more coats of primer but for the final flat I would be using at least 800 as cellulose can and will sink, sometimes weeks/months after spray/polishing etc.

 

Topcoats, apply a few light coats, then flat with 1000+

 

A few more, then flat again. I would repeat several times as celly is so thin once dry. Penultimate coat flat with 1200, final coats and then 1500-2000 grade, then cut then polish. 

 

NB I have found acrylic stopper to be brilliant for rectifying tiny blemishes as the painting process goes on, even during the topcoats....(cellulose stopper is hopeless)

[Robin]

Great - thanks Richard and Clive.

 

Clive - what do you mean by 'cut' the top coat prior to polish?

 

Robin

[Clive]

cutting compound, T cut may be ok, or G3 is very good. It is finer than the 2000 W+D paper

 

Also, 5 thin coats of celly won't be enough. Maybe 5 double coats (ie coat, leave 5 mins to flash off then coat again) but the more the better. 

[Robin]

cutting compound, T cut may be ok, or G3 is very good. It is finer than the 2000 W+D paper

 

Also, 5 thin coats of celly won't be enough. Maybe 5 double coats (ie coat, leave 5 mins to flash off then coat again) but the more the better.

 

Thanks Clive. Out of interest what happens if you don't cut back the final top coat but just apply polish?