friendly advice on panel steps

[fergo_79]

iam repairing some rust spots on my car ( vk ) i need to know once fixed the rust where do i go from there what primers do i use ?? i have read that you must put etch primer down before surface primer but how many coats of etch primer ??
then do i sand it back or just a light sand then surface primer how many coats and do i sand in between what grit if some one could take the time and help me it would be great

[scott-95]

Are you using ACID or such to clear rust? usaly we only worry about "etch" primer if its been acided to steel..

(We is refering to my work)

Edit, Unless somone is asking for it to be done with "etch" primer, oh usaly 2 coats, then standard primer over it, (DIFFRENT BRANDS REQUIER DIFFRENT METHODS!)

[fergo_79]

iam cutting out the rust and using steel to fill then what should i use from there i have no idea

[scott-95]

If, you are cutting a larger space around the rust Personaly like to go 5+ CM if posible to get rid of any steel starting to go...
normal primer would be fine

[fergo_79]

yea thats my preferred choice
so not etch first then normal?

[scott-95]

Usaly we only etch prime after acid, you should be fine, Good primer or just cheepo till done properly? i can see your fine with bog and sutch? 320 finish grit is pleny smooth for primer then light block with 320 for any run's/un even, dont be scared to RE BOG! then sand 420-500-600-800 depending on collor going to you wount need anymore dont go too smooth tho!

[fergo_79]

Just cheap bog iam gettin a pro to colour the car iam just getting it ready rust repairs and straighting panels so dont want it to start coming back rust i mean from the time i fix till time i get it sprayed as in there might be a big delay from repairs to pro spraying it

[fergo_79]

Cheap primer not bog as stated sorry

[ari666]

how i do it:

cut out rust>
weld in new steel>
grind flat, metal finish>
wizzy down with 180>
scrub rust converter over the entire repair section, everywhere that metal is showing INCLUDING the inside. if the inside is left untreated it can rust trough the really thin areas of steel left after grinding and bubbles will appear quite quickly>
allow rust converter to dry>
sand again with 180 till shiny>
bog>
(36 speedfile) sand sand sand>
fine filler>
(240 speedfile) sand sand sand>
hi fill>
(400 or 800 depending on colour on a block) sand sand sand>
paint.

seems to work for me.

[fergo_79]

Thanks mate thats what i needed to know when you say paint is that in primer or primer then colour

[ari666]

the hi-fill IS your primer, another name is primer/filler or high build primer. it should have some etch in it already. layer it on really thick so when you block it back you dont rub through in spots. depending on how anal you are, if you go through to metal on the blocking back stage, then you may need to go with another thinner layer of hi-fill.

add less reducer (5%-10%) and it comes out like mud which is great for filling thick arears, but more work to block back, add lots of reducer (30%-40%) and it comes out a lot more even which is easier to block, but its prone to runs and wont fill big low spots.

make sense?

once its all blocked back you clean it thoroughly with prepsol (wax on wax off) run a tack cloth over it and then hit it with colour.

[ari666]

some pics:

ok, so cut out all the old rusty crap:


rust convert the inside stuff as much as you can, and leave rust converter sitting on any exposed metal, just in case it takes you more than a few hours to finish cos' surface rust will appear pretty quickly:


finish the panel, grind everything flat:


rust convert again, leave it to sit till dry, wizzy back till its allllll shiny (takes ages but best to do it thoroughly). then layer on bog:


sand it with 36 to get the shape right, i go on to use fine filler from here but you can get bog pretty nice with 240, fine filler isnt cheap but sooooo much nicer to work with. then once its all nice, flat and the sanding scratches are gone, layer on a few coats of hi-fill:


once the hi-fill is dry, spray on a layer of guide coat, which is just crappy acrylic aerosol can. DONT use enamel, itll clag your paper in 2 seconds. and block back. this is the stage which will make or break the final result, so take your time. wet the block, rub rub rub, wipe, check, rub rub rub, wipe, check till it looks nice and flat:


then after its perfect, no peel, and no ripples... hit it with colour:


and then drink a beer.

[kane_coro]

How do you wait that long before you drink a beer Ari??God I have to crack one as soon as i see the rust

[ari666]

lol no, i am drinking pretty much solidly through the entire process im pretty sure that 1/4 took about 2 slabs all up

[fergo_79]

hahahaha 2 slabs hahahah thanks heaps for that its a great help

[fergo_79]

what are the usual steps for panels that are not rust affected do you sand back to bare metal or paint strip ?? then re prime and then colour or do you just take colour off to primer then re paint ?? the panels a straight and don't need any bog

[ari666]

depends on what you wanna do. if you paint strip you gotta commit to doing the whole thing, no matter what you find underneath. for example, you may think a door is dead straight, then strip it to find there are ripples all over it and a skim of bog. if you use stripper, then all that bog has got to come off and you then need to start over, however, if you just speedfile off the top of the old paint, fine fill ad hi-fill you have saved 10 hours of sanding.

but if the paint is 2k and it isnt going to fry up then you could get away with just scotchbriting it and hitting it with hi-fill.

depends on how much you are prepared to find under the paint stripper