The Spray Painting Thread

["Z" UTE]

Ah the old thinners question. What grade of thinners are you using, GP, fast, or slow.? For higher temperatures, you use a slow thinners, this evaporates more slowly, and allows the paint to flow out. Conversely in colder temp, the thinners takes longer to evaporate, so you use a fast thinners.

Today, I would use 80%-90% normal/GP thinners, with up to 20% fast thinners. Ideal spray temp for a backyarder using gp thinners is 20degC. You are pretty close. Keep your thinning ratio as normal but you may have to add a touch more thinners to get good atomisation as the colder paint will be more viscous. Warming (sun bakeing works) the panels will help the evaporation of the thinners, but it is the output from the gun that is critical.

cheers Chuck.

[oldcorollas]

Didnt want to bare metal it stew? its fun!

. I honestly suggest you get some grafitti removal discs and rip all that old paint off. About 5-6 discs and 3 hours on the angle grinder and it will be all gone.

*sigh*
what a shitful day.. had everything set up out the back to do some gun tests,to get settings right..
go inside, have lunch, get ready to mix up paint and... someone decides to hang out washing.... next to the board and paper i set up

i attacked the "good" side of the car today... hit it with 80grit orbital (a RO seems like a better idea) and took off top primer, soft blue, primers under that, hard blue... and got down to what i think is original white paint... same position is "2" in pic above, but thin and hard like original paint...
decided to try adn get all down to that, got close with orbital then hand with 120...


i thik i'm gonna go to bunnigs and look at the graffiti removal shit during the week or my arms will drop off...
as much as i hate to admit defeat... and rebog the whole other side of the car... it'S probably for the best....
going to rip off section by section, then go put on etch-primer and guide coat... lightly block it then skim with nikki and go from there...
ffffuuuuuuuuu
the disc i got last time did a fair bit of damage to the metal... hoping to find something less aggressive this time.

edit. what's really shitting me atm is around the door and side window frames, and all the little complex corners and crap... plus the big concave section all down the side of the car.... sucks for sanding....

/vent

["Z" UTE]

*
the disc i got last time did a fair bit of damage to the metal... hoping to find something less aggressive this time.

edit. what's really shitting me atm is around the door and side window frames, and all the little complex corners and crap... plus the big concave section all down the side of the car.... sucks for sanding....

/vent

The "Brumby" brand graffiti removal disc from Bunnings is way kinder to metal than the flap discs, just watch out for heat build up, if you work one area continuously.

I used a graffiti disc to "pop" a huge ding in a door by grinding at the one spot till it started to flex, them boink out came the ding.

For the window frames and complex corners, get out the old electric drill and use an abrasive filled fibre "wire wheel" made by Josco, also available frrom Bunnings. These come in various sizes, with the added benefit you do not end up with spikes of wire in your skin and clothing as you do with a traditional wire wheel.

cheers Chuck.

[o_man_ra23]

When I do the 23 I'll be using chemical stripper on the big flat bits followed up with graffiti remover pad, and bead blasting around the tricky bits/any joins (ie back of the rocker sills). I am so over manually removing paint from the complex areas it isn't funny.

I will say that a graffiti remover will way out-do a wire wheel or sandpaper for removing gooey paint/bog. This includes the early renditions of 2pak paint.

[oldcorollas]

the Josco wheel was the one i was thinking of for the annoying bends and crevices.
I might tough it out with the 80grit and orbital or the flat bits, although with soft bendy panels, that gets a bit annoying. will check out the Brumby...

[thechuckster]

Any suggestions on a stone-guard paint for the sills on my (impeding) rally car?

The car already has some sort of slightly rubbery stoneguard underneath the existing paint which I hope will come off a Bumby fibrous/abrasive disk. Am just unknown what to re-paint-it-with given the abuse it will get. The body will get the cheapest paint I can source (but it will have to cope with stuff scratching the sides of the car).


Also: given that I'll be dry-icing the sound-proofing off the floor of the Z11, will that also weaken the paint bond on the underside of the car?

["Z" UTE]

Charles, the paint you should use, on the rally car, is Urethane. It is a 2 pac paint is very cheap to buy, trade price is in the region of $150.00 for four litres of the colour and the litre of catalyst. This is the stuff used on trucks. Very durable and available in most colours.

At Summernats this year, there was a stand selling "SKIN" by the 5 metre roll. This stuff is about 0.3mm thick clear self adhesive plastic. Ideal for placing on the front surfaces of a car to reduce stone chips and impact of bugs. I would use this on the sides and front of the rally car over the top of the Urethane paint.

I hope you have a source for windscreens for the Sailplane, as you will be replacing them after each rally.

Any application of extreme temperature on a panel will have an effect on the oppsite surface, so maybe a recoat of the underside with a bitumous paint layer. Although that is heavy shite and you are removing the sound deadener to reduce weight. Again you could just use the urethane, and give it a blow over on the underside after each event. Or you could get a fibreglass underbody tray. This is what you will find on most rally cars.

cheers Chuck.

[o_man_ra23]

K&H make a non-bitumous surface coating which is over-coatable available from Autobahns et al. It is rubbery, textured, and should give a good amount of protection against stones. It will be lighter than the bitumous stuff too. Can't remember what it is called, but have a half can of it in the shed. Worked well on the 28 when I sprayed colour over it.

[thechuckster]

Thanks for that Chuck, hadn't thought about a clear film over lower panel parts. Had only seen a few folks up here selling 3M stuff for car covering but they'd priced it for the luxo market only.

No idea about windscreens but folks have been able to get replacements in Oz. Cage will be tagged to the A-pillars so it'll only be the bigger yumps that over-stress the front and crack the glass. Will be using non-hardening mastic to hold the glass in.

underside will be alloy tray under the front reaching back to the gearbox and soft stuff covering the rear (starting from the front bolts of the rear cross member). Roads up here are pretty damn rough (see the undercarriage damage to cars at the recent ARC round at Imbil) so wasn't going to consider a fibreglass undertray as it would be trashed after every event. Will think more about underbody.

[JZA70R_92]

guys quick question im repairing some little dents on my sill panel actually Ive cut it out and welded in a new section the supra has some kind of black ripple looking undercoating id like to replaicate what would it be doenst feel like asplet spray?

[JZA70R_92]

actuallu the black ripple coating is on the bottom bit of the sill as the top is body colour

also i tried that k%h stuff wasnt the same

["Z" UTE]

The black ripply stuff is called "Stone Guard" available in spray cans from most auto parts shops. Make sure you shake the shit outa the can for much longer than the can recommends. Immerse the can in freshly boiled water for 5 minutes and shake can again for 2 minutes. Then apply the stone guard.

If you do not follow my advice I can guarantee you that the nozzle stem will block up, and you will be left holding a can with lotsa product in it, but no way to get it out.:mad:

cheers Chuck.

[JZA70R_92]

yes the mad part ill get some and give it a try ive seen some supras where they paint the whole sill body colour and it looks wrong

[o_man_ra23]

The K&H stuff did have a different texture to the OEM gear, however it appears to be essentially the same stuf (same consistency after cure, just a different texture due to the different application method). If you are doing a whole car, the K&H should be fine.

[oldcorollas]

what about the stuff they use for lining ute trays etc?


i've been converted.. going to rip the crap paint off and start again... yeah i know i shouldhave just done this ages ago but now i have a pack of 80grit

plan =
1. rip shit paint off, to near metal with 80dry, and plastic wire wheely thing
(there is brownish coating, and then maybe original white paint, so somewhere near there)
2. smooth it a bit with 120dry, then 2 decent coats of 1K etch primer + guide coat
3. lightly block to find bumps (tap in and fill) and hollows (fill with nikki). fill and build as much as possible on the rooted bits.
4. 240dry to smooth/key, then 1 or 2 light coats primer, couple of spray putty (fill scratches etc), then guide coat.
5. 240dry (320?) it all smooth and fix any misses.. then couple of good coats primer
then when thats fiiinally done
6. 600 or 800 (dry or wet???) the primer and shoot the colour.
(going to do 1-5 section by section, then shoot colour on doorjambs, edges, corners inside etc.. then hang panels and do outside colour as a whole car)

suggestions? different grades of paper? wet vs dry? (I'm still summarising the thread )

before spraying the primer and putty, just wipe with wax'n'grease remover (and wipe off) and good to go??
no need for sugar soap or tack rag until near colour stages? (no need for sugar soap at all?)

edit, apologies for all these long posts trying to get it ordered in my head before i breathe in too much dust...