Enamel Painting a 90 Body

[John_M]

Hi guys, fairly new to the forum (and working on land rovers).

I'm currently trying to bring our old 90 up to date a bit (small bits of body and chassis work to keep it going for a few more years). Having done some body work, I need to look at respraying. It's overdue a respray, there's spots of aluminium corrosion showing through now. 

What advice do people have when it comes to respraying, especially around paint brands/types? I've been looking at enamel paints, but I can't tell if I need to apply a topcoat over a gloss enamel paint, or if (because its already gloss) it doesn't need a finish

Any advice appreciated!

[FridgeFreezer]

Speak to these guys: https://paintman.co.uk/

[miketomcat]

I've had good results with por15 on the corrosion spots. Wire brush, spot paint then you can move on to primer, filler if required etc. I like 2k paint but you need air fed hood really as it's nasty stuff. The single most important thing I found out after I painted mine is, primer (etch if bare then filler primer) BEFORE filler then more primer. The car industry seams to fill bare metal, this is WRONG it does not stick and will fall off. Unfortunately I believed the millions of you tube videos, then when mine started coming adrift I asked a boat painter at work.

Mike

[steve b]

Enamel does not need a clear coat , the gloss is the final coat. One point to note is enamel will fade over time.

As Mike says above etch prime all bare aluminium spots, then a primer coat and filler if needed followed by primer undercoat ( I use top coat colour for the primer undercoat for a true top coat colour) 

Steve

[John_M]

So, just to check @steve b, an etch primer is different to a standard primer, because an etch primer etches the metal to provide a better surface for another primer or filler to stick to?

Also, am I right in saying enamel is harder wearing than standard paint + topcoat? Even if it fades over time?

Thanks!

[steve b]

The etch gives a properly attached coat to bare aluminium - an ordinary primer will lift/peel on bare ally. 

I would say 2K is harder than enamel - any thoughts @Eightpot? I'm pretty sure you do more than I do.

Paint/bodywork is 98% prep and the right paint and 2% spraying...

Steve 

[Bowie69]

2K is much harder than enamel... And much more resistant to things like brake fluid, something that may be needed on a LR! 

[reb78]

But 2k needs more expensive and involved respiration gear??

[John_M]

So, 2k seems the way to go. Would anyone recommend any specific vendors/brands? (I've got respiration gear so thats not a problem)

Also, is it worth taking it all right back to the ally (ie strip all current paint) before even priming? Sand with some 60-120 grit, then etch prime the entire body, then use 2K?

[Bowie69]

You need to be careful with all paints, frankly, try painting a car in a enclosed garage with enamel 😁

[reb78]

1 minute ago, Bowie69 said:

You need to be careful with all paints, frankly, try painting a car in a enclosed garage with enamel 😁

I agree that none are good for you, but i have heard bad stories about 2k nearly killing people

[Bowie69]

Mostly they are stories, and prolonged exposure situations. 

With a decent mask and ventilation it is fine to do DIY, I mean, I'm still here... 

But of course, don't do it just because I said so 😛

There's risks as with anything, but decent precautions and knowledge will get you through. 

[Snagger]

Let’s be honest - paint spraying and good ventilation don’t go hand in hand unless you want orange peel, runs, overspray and plenty of dust and dirt inclusions.  Breathing gear is going to be important no matter the type of paint, but while some paints will just require passive masks, some paints will require air-fed mask under positive pressure.

[Eightpot]

13 hours ago, steve b said:

The etch gives a properly attached coat to bare aluminium - an ordinary primer will lift/peel on bare ally. 

I would say 2K is harder than enamel - any thoughts @Eightpot? I'm pretty sure you do more than I do

Yes 2k is harder, but 1k polyeurethane aka enamel also sets much harder than acrylic or cellulose. It takes a lot longer to cure though - touch dry over several hours but a several days or longer to harden.

Goes on nice with a 1.5 or larger tip spray gun or you can get good results with a roller and brush - it tends to shrink back a little when curing so takes some of the marks out. 

Use a very good mask and ventilation with any of the paints - you don't want airborne enamel hardening inside your lungs...

2k should be avoided without proper ventilation and air fed mask - yes you can get away with it a few times, but the isocyanates in the hardner are highly toxic and non-organic : once it gets in your body through skin/eyes/lungs it can't get out and is not very organ friendly to say the least. The long term effects of getting it in your system are very nasty indeed but the manufacturers don't really like to mention it..😕

Oh and everything mentioned on etch is correct, it bonds into the ally where ordinary primer doesn't,  but don't use it like normal primer, just a light dust coating, then your filler and primer over the top. 

Edited December 11, 2023 by Eightpot

[John_M]

So, to build a very simple plan of how i would go about doing it, going of @Eightpot's post (please correct me if I'm wrong):

1. Strip back the original LR paint with an angle grinder (something like a poly disc or high grit flap disc so i don't eat away the ally).

2. Etch prime everything

3. Sand back with 180 grit or something similar

4. Apply filler and sand back again with 300 grit

5. Apply a hi build 2k primer (with same colour as topcoat, thanks @steve b)

6. (I would say sand again but from my research I'm not sure. is this where you sand with a high grit like 1500-2000?)

7. Apply 2k topcoat

And because its 2k it doesnt need a clearcoat/laquer, or buffing, because it dries with a gloss sheen

Please correct any of that if its wrong!

 

[Eightpot]

You dont have to take all the paint off, if its not flaking, bubbled, wrinkled or some other issue you can leave sound well attached paint and just smooth the surface with 180-220 and prime.

Polydiscs are good if you do want/need to go bare metal though, or just use 120- 180 grit discs.

Yes any bare metal, dust with etch, normal primer for anything else.  If you've primed over filler, leave 24 hours before painting or you will get paint sink which will leave big marks in the paint.

300 is too fine for filler, use 80 for initial shaping of big dents, 120-180 for finishing up before hi build primer.

Wet sand the primer with  400-1000 before top coat, make sure it's very dry before painting.  You can use finer if you want.

If you're going to use 2k remember my earlier comments, treat it like poison, don't let the hardner, mixed paint or the atomised spray get on your skin, your eyes or your lungs, and make sure the area is very well ventilated.  

2k doesn't need lacquer,  whether it needs buffing or not depends on your skill at painting and the kit you're using - if its your first attempt it may need a bit.. 

Let me know if you have any questions..

 

[FridgeFreezer]

1 hour ago, John_M said:

1. Strip back the original LR paint with an angle grinder (something like a poly disc or high grit flap disc so i don't eat away the ally).

I'd exercise extreme caution even with those discs, a flap wheel in an angle grinder can go through thin aluminium in moments and all the poly discs I've seen/used are a super expensive way of cleaning anything - very nice if you've got the budget but I can't imagine how many of them you'd have to buy to strip or even flat an entire vehicle

I'd be tempted to just flat all the panels with something gentler and paint over, depends how showroom you're aiming for I guess.

 

BTW I've heard good things about the static-cling plastic sheeting the professionals use, you buy it by the reel and hang it up to create a curtain around the vehicle, the static it generates attracts all the stray paint particles in the air. Jez used it to paint his Land Cruiser and it certainly cut down the number of yellow-tinted things around the workshop in the aftermath compared to previous adventures.

Also @Shackleton has some good DIY/semi-pro painting videos on his youtube that are very good - he's shacked up over a professional paint shop so gets all the proper tips and passes them on to us.

 

[John_M]

Brilliant. Thanks so much for the advice guys. My plan is to do a test run with a small section (I'm thinking the safari door, as I've got it of at the moment to do some body work). then if all goes well, move up to the main body. Also @FridgeFreezer thanks for the tip on the static sheets, my plan was just going to be some polyurethane or painters sheets, but I think I'd prefer something that can actually attract the paint away considering the dangers of 2k, so static sheets look ideal.