The Car Thread

[Skoze]

got the Capri in with my uncle for a thorough check over, turns out my springs are loose when both fronts are off the ground (quite embarrassing), but apart from that and the big holes in the footwells it's actually all good - might be a future for it after all.

We also found some coolant leaking out from one of the core plugs which is shit, think the plan may be MoT it and then find storage until i've got the money to run it again/ dot he engine swap - just need to find somewhere!

[RobinJI]

... turns out my springs are loose when both fronts are off the ground (quite embarrassing)...

Am I right in thinking you've got coilovers on it? If so that's pretty much the norm. Just fit helper springs if it worries you, but it's fine to leave it really, as long as they re-seat when you put it down without being guided it's not an MOT problem.

[Greetings]

Not sure if that's supposed to be a sarcy response, but I just wanted to make sure you didn't die!

Somewhere between sarcastic and being rather thick. Probably the latter

A f**kup has taken place.

Only managed the front bumper with satisfactory results. Thankfully haven't started on the bonnet yet so hopefully I'll be wiser by the time I get to it.

This is the bumper, I'd call the result more than adequate (the white spots on the front are holes from someone using self tapping screws on the number plate).

Boot seems satisfactory until a 90* shot is taken:

And to put a long story short, I'm rubbing down a painted rear bumper. Note the primer patch:

I'm seeking confirmation that the reason for the boot issue (and rear bumper) is bad preparation. I'm guessing the primer wasn't perfectly smooth and as a result the base coat had to fill in the unevenness causing an odd reflection. We got that on the front bumper but just put another thick coat on and that solved the problem.

So as not to go through preparation again, is it ok if:

1. The boot which already has clear on it is rubbed down and has a base coat applied directly onto the clear?

2. The rear bumper since it's only got a base coat, is rubbed down and has another 2 coats of base applied before clear comes on?

I genuinely don't like the colour of that car but having looked closely at all the pearl colours in the paint on a single drip, it should be absolutely beautiful. Got gold, black and red all in one little drip.

Also rather annoyed because this paint is 6x more expensive than the M3 imola red. Probably wasted half the paint we had today. Talking of which, I had no problems of this sort painting the M3, presumably it's something to do with flat colours being easier than pearls or metallics?

Edited March 17, 2014 by Greetings

[Skoze]

Am I right in thinking you've got coilovers on it? If so that's pretty much the norm. Just fit helper springs if it worries you, but it's fine to leave it really, as long as they re-seat when you put it down without being guided it's not an MOT problem.

That's interesting to know, cheers! I think what i'm gonna do is fit some shorter, slightly softer ('cos the 275lbs are killing me) springs with some helpers just to keep it all fully decent - it's never really bothered me as I know it's all solid and i'm not gonna be doing nay Dukes of Hazard jumps or anything, i'd just rather not have the aggro of fighting my corner with it when the test comes round next month.

[Tom Booth]

What products are you using Alex? Is your lacquer a single pack or 2 pack lacquer?

If it's a single pack I'd give it 24-48h to fully cure in a warm environment before reworking. 2 pack is a different story thou and might give you issues until fully cured.

When you mention about the boot lid, what problem are you referring too? The hazing?

Pearls and metallics are slightly thinner in make up than solid colours, hence your issues. What thinning ratio are you using for your basecoat?

[Prawny Baby]

Went to Bedford with CGTI

Had an AMAZING day, car was absolutely perfect:

managed to rack up a stonking 242 miles on track!

And Jonny caught almost all of it on his awesome Roadhawk HD camera setup!

Top day out!

[Jake.]

Matt, my caddy did it on the drive side. Was just an advisory to keep an eye on it.

[AdamR28]

Vids please Nick

[Greetings]

What products are you using Alex? Is your lacquer a single pack or 2 pack lacquer?

If it's a single pack I'd give it 24-48h to fully cure in a warm environment before reworking. 2 pack is a different story thou and might give you issues until fully cured.

When you mention about the boot lid, what problem are you referring too? The hazing?

Pearls and metallics are slightly thinner in make up than solid colours, hence your issues. What thinning ratio are you using for your basecoat?

Based on what I found in google, it's a single pack. I was told by the paint shop to thin it 1:1 with paint thinner, nothing else is added. I got the thinner with the paint so it should be the right stuff. That's for the base/colour. Clear is mixed with a hardener 2:1 but that's not causing problems thankfully.

The problem I'm referring to is that the colour is not uniform. I don't know what course of action to take, can I roughen up the clear coat and apply the paint directly or does it need to be primed again? It's apparently recommended this paint is applied onto a light grey primer.

I'll wait another day before re-working the bumper as advised. Really scared of doing the bonnet. I'll prime it again today and make sure the surface is perfect before applying paint. For some reason when I primed all the panels the result was a very rough surface which needed a lot of rubbing down during which I'd often get through to the old colour. I'm not using shoddy materials, must be doing something wrong.

[Pashley26]

Just drove a remapped 330d coupe.

Jeeeeeeeeesus that's a lot of torque!

[TROYston]

The 330d is 'the best car ever' so it's to be expected? Which 3 series?

[Tom Booth]

If that hazing is in your basecoat I'd be looking at spray pressure, conditions and application then Alex, what are you painting at?

[Pashley26]

The 330d is 'the best car ever' so it's to be expected? Which 3 series?

E forty six.

[Greetings]

If that hazing is in your basecoat I'd be looking at spray pressure, conditions and application then Alex, what are you painting at?

4bar, the gun goes up to a maximum of 4.5-6bar. Not sure how maximum pressure can be a range but that's what it says on the box.

I've given the rear bumper a re-spray and it's gone well. So possible causes could have been pressure, incorrect preparation and possibly bad thinner. Need to re-do the boot and get down to bonnet preparation.

[Tom Booth]

4bar, asin 56psi?!

Drop it to around 25-30, a smidge more thinners and warm the environment and you should get a nicer flow.

[Tom Booth]

That said, that's assuming your using a hvlp gravity gun.

[Greetings]

This is exactly what I'm using. I've tried to determine what type it is but with no luck.

I'm currently rubbing down the clear from 2 days ago (boot problem with artifacts). Can one put the laquer directly onto the roughened clear or should I prime it again? Can post a pic if needed. I'd rather avoid having to prime it again if possible.

Also thanks for your help, greatly appreciated. I'm a bit lost with this colour to be honest, M3 was way easier. Any help is invaluable, I don't know any painters to ask directly.

Edited March 18, 2014 by Greetings

[forteh]

When my dad was hand painting vintage motorbike mudguards he would brush a coat on, leave it to harden then rub back with wet and dry before washing and recoating.

He got it glass smooth with lots of thin coats and then waxed it, guess you would just be layering clear coat instead of waxing though. Surely you should just be repeating the same process rubbing down between coats with increasingly finer grades until you're doing it with cutting compound?

[Greetings]

Presumably what you're talking about is acrylic paint?

I wouldn't have any objections using this method if only it didn't take so long. Through my incredibly limited experience, I prefer to apply a thick final clear coat (not too thick so as not to get runs). That's good for some proper rubbing down and polishing.

Currently waiting for the colour to dry a bit, painting the boot again. So far so good. 1 final coat of colour and the clear can go on. That will just leave the massive bonnet... my plan is to be anal with preparation.

@Tom - I tried using a lower pressure and thinning the paint further and got a very uneven and thick spray (just small blobs rather than "atomized" paint).

Edited March 18, 2014 by Greetings

[forteh]

He was using enamel paint so even slower to harden! I don't have any experience of painting vehicle bodywork but I reckon lots of thin coats of colour lightly flatted back between coats before hitting it with a couple of heavier coats of clear before polishing.

Tom will probably come prove me wrong

From my experience with airbrush spraying it's simple a balancing act of pressure vs paint viscosity, thinner paint requires less pressure. Too much pressure and you will get the paint drying before hitting the target which will result in a rough finish, too much thinners and the paint will be too wet when landing and cause runs it spiders if the pressure is high enough - again Tom will be along shortly

Edited March 18, 2014 by forteh

[Tom Booth]

I'll go with most of what Ed says, the only thing I'd dispute was flatting between coats. Flatting metallics before clear gives all sorts of nasty ghosting and 'cuts' the heads of the metallics meaning it looks awful really.

The rest of your advice is pretty sound thou Ed. Painting really is just finding your balance to get a nice flow. What sorta conditions are you painting in Alex?

[forteh]

Ah yeah I hadn't considered that metallics would need different methodology

Cold air and humidity can have bad effects on spraying, might be worth running a dehumidifier in the cellar if you can, or at least put a hygrometer in there to see what you're trying to deal with. You said that the wall paint is flaking, that indicates damp to me, you might be able to dry it out though if you can apply enough heat.

[Greetings]

The conditions are probably far from ideal - at a guess 10C, humidity is low, around 50%. I will increase the temperature to 20C (if possible) for the bonnet.

I think I might have found a nice spot for pressure and viscosity because doing the boot was a doddle compared to the other parts. Very nice spray. Unfortunately I'm getting a spider web sort of finish here and there. I rubbed down the affected spots with 1000 paper and gave it another coat, that sorted out most of these areas apart from one.

Going to wait another 30 minutes for it to dry (still slightly sticky), rub it down and hopefully the final coat will not crack like this. Then it's clear and off to bed.

Tom, are you a painter?

[Tom Booth]

I am by trade I used to paint classic jukeboxes and there parts, but at the same time I painted all sorts from machinery to wooden cabinets, at the minute I work in a paint supplier.

If I was you Alex in this situation I would do the following -

Flat all panels to be painted that have gone wrong with 600-800, keeping there shape and form without rubbing through your coatings of clear, this will 'open' the lacquer up allowing it to dry fully (imagine the skin on a porridge/gravy, thats what part cured lacquer does, the first few mil of paint skins over trapping the soft 'wet' lacquer underneath, although it's touch dry it's not fully cured).

Leave them in a warm environment for a few days/a week (room temps fine), this will allow the solvent to dry in your lacquer and hopefully any gremlins that will give you a problem to dry. Check the panels for any defects, if there's no problem hit with a last run of 600grit and wipe with a degreaser.

Warm your environment as best you can, anything room temps ideal, thin your basecoat between 2-1 and 1-1 ( I always find somewhere in the middle is a happy mid ground but I'm always working with mini guns with a 1mm needle, 1-1 seems to give you grief on any slightly unworked edges). Set gun pressure around the 1 -2 bar depending on the paint suppliers recommendation and your gun tip.

Hit with a light coat of basecoat, allow to dry, check for reactions (the spiderwebbing in your picture is down to the basecoat thinner soaking through the previous layers and finding a problem for you, thinners 'searches' through soft finishes allowing mild adhesion) if the problem has gone rub the panel down with a scotch pad to key up again, a quick wipe with degreaser followed by 1 full coat of base, leave to dry for 20mins till a satin finish is even across the panel. Drop gun pressure 5-10% for your final base coat this helps the metallics settle better on the panel and sit up right (funnily enough this is called a drop coat).

Leave 20mins then proceed with 2-3coats of lacquer. I always apply 1 unthinned coat of lacquer lightly, then a 2nd coat with 5% thinner and a final coat with 10% thinner. Treat the first coat as an adhesion coat, the 2nd coat starts to build your sheen then the 3rd coat fills your orange peel nicely and leaves you with a nice gloss. That's what works for me, I paint items most days too using that system with great results. I know a lot of people that just drop 2full coats of lacquer on, if I were to paint something like a bonnet/boot I would, but painting bumpers with the scoops etc applying 2/3 lighter thinned coats allows the build/shine and good finish without the risk of runs and sags, minimising work after.

What paint manufacturer are you using Alex? There will be a technical data sheet online to give you thinning ratios and spray pressures to give you the best results.

[Jake.]

Caddy had to be towed home tonight.

Felt like I had run out of fuel, nope, half a tank left. She starts, but when you try and move forward she shudders. Fairly sure there's air in the fuel lines or somethings up with the fuel pump. Hope I don't have to buy a new fuel pump.