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sedge
19th September 2004, 20:14
Ok, I'm sure someone else must have done something like this.

I bought this bike and it was bit too red for me, so I thought I'd change it a little...

Took all the fairing off and wet and dry sanded it, cleaned it up with turps, masked some bits off and then used some sprays cans to make it a little less red...

All this went surprising well, did a couple of coats and it looked pretty good. Left it for a coupel of hours and then had a flash of inpiration and thought I'd clear coat it for protection... Off to Repco again...

When I sprayed the clear a section of the paint started to crackle before my eyes (there may have been some swearing and dancing up and down at this stage while I waited to see how far the crackle would go) luckily it is confined to the space under the belly pan where you can't really see it.

Later on I looked at the rest of the bike and noticed that the clear coat had acted like a solvent and actually made some of the paint run ?

What have I done ?, both the clear and colour are VHT enamel from Repco and there's nothing on the can about mixing them ?

Anyone ?

Sigh, I guess I'll have to spend yet another fine day next weekend fixing my bikes instead of riding them...

Sedge.

Motu
19th September 2004, 20:49
I'd say the clear coat was laquer,they usually are - and laquer thinners is a solvent,acetone,or close to.

DEATH_INC.
20th September 2004, 06:58
I'd say the clear coat was laquer,they usually are - and laquer thinners is a solvent,acetone,or close to.
Yeh,I'd be checking the cans,the red is prolly enamel and the clear laquer.
You can put enamel over laquer,but not vice-versa.
The only way to get rid of it is to sand it right back to the plastic and start again....

Blakamin
20th September 2004, 08:22
Yeh,I'd be checking the cans,the red is prolly enamel and the clear laquer.
You can put enamel over laquer,but not vice-versa.
The only way to get rid of it is to sand it right back to the plastic and start again....
Exactly!!!!
try not to use animal (enamel) on your bike at all.. when it left the factory it was more than likely painted in acrylic

Dodgyiti
20th September 2004, 08:45
Dodgy paint job?
Wasn't me.. :o
Also allow at least 24 hours cure time, maybe more this time of year
Can I advise the little airbrush guns for m/cycle paintwork. 40 bucks and ya don't need a compressor, just some old innertubes. Had mine a couple of years and it is a little legend

Paul in NZ
20th September 2004, 09:09
Dodgy paint job?
Wasn't me.. :o
Also allow at least 24 hours cure time, maybe more this time of year
Can I advise the little airbrush guns for m/cycle paintwork. 40 bucks and ya don't need a compressor, just some old innertubes. Had mine a couple of years and it is a little legend

OK.. Spill yer guts Guzzi boy.. This sounds like me.. I want to do the Triumph tank soon... Where, what make / model etc and I assume the tubes are your source of compressed air?

sedge
20th September 2004, 11:29
Thanks everyone,

I guess I was trying to put the clear coat on too quickly after the base coat. I'll sand it back and try again sometime, probably just touch it up for now coz it's only a couple of spots that look crappy (did I mention I was a slacker ? :) )

Cheers,

Sedge.

Blakamin
20th September 2004, 11:36
Thanks everyone,

I guess I was trying to put the clear coat on too quickly after the base coat. I'll sand it back and try again sometime, probably just touch it up for now coz it's only a couple of spots that look crappy (did I mention I was a slacker ? :) )

Cheers,

Sedge.
The clear is an acrylic.. you could leave it for months before putting it over enamel. it will still "crackle"
this has been used to paint custom finishes on cars since the 50's..
you'll have to get an acrylic paint instead of the enamel... get one of the touch-up colours for cars, not VHT paint

Marmoot
20th September 2004, 12:15
That's basically right....

The best is to primer the bastard first, then you can use virtually any paint you want.

But it is very recommended to use Acrylic for the primary paint.

The clear coat ideally should be of different type than the primary paint, to make sure there is no mixture.

kerryg
20th September 2004, 14:17
OK.. Spill yer guts Guzzi boy.. This sounds like me.. I want to do the Triumph tank soon... Where, what make / model etc and I assume the tubes are your source of compressed air?


Yeah...more info please (this sound interesting)

Blakamin
20th September 2004, 14:56
The clear coat ideally should be of different type than the primary paint, to make sure there is no mixture.
where did ya get that from??
when i'm painting a car i add clear to the last pot of colour so they dont ever seperate... havent had a complaint yet

Marmoot
20th September 2004, 15:00
where did ya get that from??
when i'm painting a car i add clear to the last pot of colour so they dont ever seperate... havent had a complaint yet

hey, that worked fine? I've never tried that.
Should try it one day....

I normally do coats after coats. And 3+ layer of clear coat works wonder :rolleyes:
Give that wet shine look, you see....

Better yet. Paint the darn thing, the attach any stickers on it first before clear coating.

Blakamin
20th September 2004, 15:22
hey, that worked fine? I've never tried that.
Should try it one day....


i've done it since i was about 17 with acrylics... I dont really bother doing it with 2k coz with the hardener it wont go off till its ready anyway, i just let the thinner "flash off" so as not to load up the surface and cause sags etc. once its baked it should never seperate unless there's contamination between coats.

thats also the reason i never use silicon based polish for anything i own, too hard to get rid of it when i change colour.
i also get bored of a colour quick so my bike will probably be red by the end of the year

:niceone:

Marmoot
20th September 2004, 15:31
ah....probably we are coming from opposite angle.

You came from panel painting so that would work fine.

I go from airbrushing, so clear coat has to go last after all the details are done.

But I'll keep your suggestion in mind when I need to paint something with single colour.
:niceone:

vifferman
20th September 2004, 15:43
ah....probably we are coming from opposite angle.

You came from panel painting so that would work fine.

I go from airbrushing, so clear coat has to go last after all the details are done.

That's right. In fact, to give real depth, the solid colour coats are often followed with mixed coats of colour/clear mixed, each coat having progressively less colour and more clear, then a number of just clear coats.
Used to work in a furniture shop, whose painter used to do custom cars etc. He explained to me the process after I trashed an item of furniture (by not tying it into the delivery van securely) that he'd spent LOTS of time finishing like this...:Oops: :doh: :argh: :blank:

Blakamin
20th September 2004, 15:54
That's right. In fact, to give real depth, the solid colour coats are often followed with mixed coats of colour/clear mixed, each coat having progressively less colour and more clear, then a number of just clear coats.
Used to work in a furniture shop, whose painter used to do custom cars etc. He explained to me the process after I trashed an item of furniture (by not tying it into the delivery van securely) that he'd spent LOTS of time finishing like this...:Oops: :doh: :argh: :blank:


ouch!!!... yep that be the process...

i normally use a 30/70 mix then keep topping the clear till its about 2/98 then run the pot empty. (depending on size) and then a pot of straight clear to finish off!

sedge
27th September 2004, 09:00
For those of you that are interested...

Here's the finished paint job, it looks kinda orange in the photo for some reason, I guess it was the searing sunlight we had yesterday ;). If you look closely you'll see the gear linkage is disconnected, it's not that I have giant clown feet, I'm getting another one made up (linkage that is, not a foot).

I guess you can't really tell what I've done so I've included the original as well, you'll also notice the Wiseco pistons sticker upgrade kit... now with 20% more sticker power...

Heh heh... Sun, a bike or two, beer and contact adhesive fumes... I really like Sundays.

Sedge.

NC
27th September 2004, 09:12
Ah dude, bad luck :(

I really need to Re-paint my bike, but I hate sanding..

sedge
2nd February 2005, 16:02
Sigh... you think I would've learned my lesson... I Painted up my new streetfighter headlight surround on the ZXR (looks cool in matt black) waited 24 hours... applied clear coat... paint falls off !

Right well... lessons learned, 1. test a bit first 2. VHT enamel matt black and VHT enamel clear coat DO NOT mix well as they are wankers. & 3. Get someone who knows what the hell they are doing to have a go at it.

Blakamin... I may be coming to see you soon...

Sedge.

Motu
2nd February 2005, 16:27
I'm pretty sure the clear would have to be laquer,and it's not what you want to put over fresh enamel.Check that can again,bet it says laquer - did it smell really good/

sedge
2nd February 2005, 16:34
Nah... I made SURE this time after stuffing it last time... Grumble mumble arse etc.

If it smelt good I wouldn't be so worried, I'd still be in the garage inhaling it.

I'm going to have to get some real paint and do it properly, the can enamel is soft and chips too easily anyway.

Sedge.