Preparing a for for spraying

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ndevans
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Preparing a for for spraying

Post by ndevans »

Hi.

I'm preparing a passenger door for spraying. It's already got grey primer on it, but it's a bit patchy, and rough in places, so I'm going to sand it first, before spraying with cellulose primer then gloss topcoat.
Is it ok to sand using sandpaper, as opposed to wet & dry?I would normally use wet & dry, but all I have at the moment is sand paper and some 120grit aluminium paper.

Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

Amy mods who view this, could you please kindly change the topic title to Preparing a door for spraying? I can't edit it!
Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
kennatt
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Re: Preparing a for for spraying

Post by kennatt »

120 grit is a bit too much for final prep. you really need to get 1200 wet and dry and use it dry. If you use it wet it can introduce dampness into the primer which you need to get rid of COMPLETELY before top coat .Don't use the 120 it will cause fine scratches which will show in the top coat. Give the primer a sand over with 1200 then with a can of contrasting colour Ie black on most coloured primer give the whole door a very fine dusting no solid colour anywhere just a light dust over,then with a flat block ,again with the 1200 flat it down again .High spots will shown as no black low spots will show as black areas,keep adding coats of primer until when re dusted and flatted no high or low spots or scratches show.Its a painstaking process but its the way to get a pro finish.
be aware that when you put the top coat on with celly it will dry out dull,its not very good quality these days,not like back in the days I was involved if re spraying (Hence all pros have gone to "2k or water based oven drying); Just be sure you have a good two or three coats on so that there is enough depth to t cut it back to a shine. Good luck
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

IMG_20200726_181905~2.jpg
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Two thin coats of primer applied. Needs a rub down, then maybe one more coat. I have managed to get some 400, 1000, 1200, 1500 & 2000 grit wet & dry now.

The coach line on my car (1969 Traveller, Almond Green) is gold, in the form of an adhesive strip. I know that originally it would have been porcelain green, why it's been changed I don't know. I like the gold, so it's staying.

Was the coach line always an adhesive strip originally, or were they painted on?

Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
ManyMinors
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Re: Preparing a for for spraying

Post by ManyMinors »

The coachlines were always painted on. By hand.
Most of us don't have such a steady hand to perform this task(!) Special lining tape is available - manufactured by 3M I think?
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

Progressing nicely, but I am in danger of running out of cellulose thinner. Where do I go to get high gloss, premium cellulose thinners these days? Most places say you can't get it now.

Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
philipkearney
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Re: Preparing a for for spraying

Post by philipkearney »

If you can't get any thinners from local body shop suppliers or motor factors, I'd try Ken and Lynn https://www.carrestorationpaints.co.uk They should be able to supply you with high quality cellulose thinners - and pretty much anything else you will need for the paint job too !
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

Thanks, I have managed to find a local supplier now.
Cheers N
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
ManyMinors
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Re: Preparing a for for spraying

Post by ManyMinors »

I have purchased cellulose paint and best spraying thinners from Ken as recommended above and found their products to be excellent :) .
kevin s
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Re: Preparing a for for spraying

Post by kevin s »

I have found using epoxy primer under cellulose works really well, it doesen't absorb water or sink like celly primer.

This is a wing I recently did in this way.
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

Worth knowing, thanks. I've had problems with non-cellulose primer in the past, I think it was acrylic, that caused the cellulose top coat to wrinkle.
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
kevin s
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Re: Preparing a for for spraying

Post by kevin s »

The reason I was painting the wing above was because of acrylic under cellulose, it crazed and started flaking off.
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

Think some paints work ok with cellulose, others not. Enamel seems ok, and I'm sure I've used acrylic with cellulose before, but when I tried acrylic primer on the bonnet, it didn't work. Maybe it depends what order you use it in?
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

More progress.
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It's run a little bit, but it'll look a damn sight better than what's on the car currently.
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

It's not obvious from the photo, but the finish is slightly orange peel. How do I correct this, and how do I avoid it?
Thanks,
Neil
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
kennatt
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Re: Preparing a for for spraying

Post by kennatt »

Difficult to get a finish in celly without orange peel / dull areas, depends on the skill of the painter, and the quality of the gun,best guns are too pricey for one off use, in the early days it was prevented by thinner and thinner coats of top coat until you were just about spraying neat thinners.But the quality of celly thinner has dropped over the years and the only way a diy'er can get a perfect finish is to compound it flat Tcut ,compounding paste,various products on market .finest wet and dry used with soap etc.Depends how bad it is,if only slight just leave it and over time after regular polishing it will got flat(eventually).If it is annoying you T cut,being mildly abrasive will ,again eventually get it flat,Just make sure you don't cut through to the primer.Its why all pros are now using 2 K,or water based in an oven,2 Pack dries out virtually flat and shiny from the gun. Celly is ,and always was a bit of an art. But well done,looks ok.
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

Ok thanks.
I'll flat it with wet & dry, then try another coat. I used a 50/50 mix, I'll try a thinner mix. If no better, I'll just flat it & polish.
Even with orange peel, it's better than what's on the car. Two different shades of green, and the bottom 10cm full of rust and filler, and bulging in places.
Last edited by ndevans on Wed Sep 09, 2020 2:28 pm, edited 1 time in total.
cheers N

Image
33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
win
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Re: Preparing a for for spraying

Post by win »

I personally prefer to look at a respray with orange peel or any other imperfections when done by an enthusiastic amateur than look at a bright shiny cheque book respray.
A great many people know how much effort has gone into it.
Keep up the good work.

Everybody to their own, I still admire the finish on some professional ones.

Regards Win
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ndevans
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Re: Preparing a for for spraying

Post by ndevans »

Yes, I'm with you on that. Sometimes things can be too perfect. My car has a few imperfections on it, including a slightly warped panel which my dad and I replaced when we did the wood. It's not perfect, but the imperfections make it mine. You could respray that car a totally different colour, and I'd still be able to identify it.

Anyway, another two coats applied tonight. Some improvement, but there's still a bit of texture there. I think I was using the gun on too low a volume setting, and it was atomising too much. Increasing the volume has helped a little, but it also ran a bit. There's about 5 coats on there now, so I'm going to call it a day and spend some time rubbing it down.

Current state of play:-
IMG_20200909_213341~2.jpg
IMG_20200909_213341~2.jpg (1.47 MiB) Viewed 1903 times
Yes, that is another spare door in the background! It's no better than the one on the car though, needs a repair panel for the bottom 10cm.
cheers N

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33063, Eridge, Sept 2021 by Neil Evans, on Flickr
'69 Traveller, 1275, discs.
kennatt
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Re: Preparing a for for spraying

Post by kennatt »

it's better than two coats,you have plenty of thickness to cut back and polish,fine wet and dry with soapy water to get a dull overall finish ,then polish with t cut.To be honest its what we used to have to do in our family paint shop(In another life ),its always the same problem with celly. 50 years back,not a problem but gradually the quality of the thinners(the paint was the same)gradually dropped.I understand that celly was first used after the 2 world war because there was a vast quantity of Gun cotton in the country and it was found to be a good way to produce thinner and get rid of it.Now I understand its reclaimed over and over so not same standard.If you are going to do more work suggest you buy an electric polishing mop,gives a better finish quicker and prevents dull patches because it does a larger area than by hand. Or if you like a random orbital sander which has a polish mop, also very good for flatting old panels and filler prior to repainting . Good luck
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