Spoke too soon!

[Steve1968LS2]

Originally Posted by camcojb

Well, most of you saw my new paint pics. Upon further checking tonight there are some issues in the paint and without writing a book it's going to need to be stripped and re-painted. I will paint it this time, I've learned my lesson!

Jody

Wow.. does this story sound familiar to me...


Sorry to hear and I feel your pain...

[ProdigyCustoms]

Hum, and here I thought catalized material dryed through chemical cross linking, not evaporation. I dont know why I thought the reason we eliminate more and more reducer from paints, clears and primers, some materials down to 10% or less, is because of a chemical dry. I know when I used to do laquer, and we used to add 1 1/2 gallons of reducer to 1 gallon of paint or clear, it was evaporation. I also thought the reason you could spot blend a laquer car 20 years later was because it was a evaporation dry, and since there was no cross linking, you could always revitalize and penetrate it with thinner. Oh well, I guess I was mistaken. I try to learn something new everyday. I'll bank this one.

[race-rodz]

im with frank on this one...... any problems with the reducer not evaporating would also tell me the wrong reducer is being used, not enough flash time, or some other kind of operator error.

as with almost all chemical reactions.... heat speeds up the process, so when the car is baked... you are speeding up the cure time but speeding up the chemical reaction. every tech sheet i ever read says to allow ample flash time before baking cycle.... so as to not trap any solvents.

as for most of the paint being equal nowadays....... i couldnt dissagree more. i try new products on a regular basis... and sometimes i find a product that suits my needs better.... maybe it goes on smoother... maybe it cures faster... maybe it polishes better. if they were all pretty much the same... then this wouldnt be the case. each "brand" has its own charateristics that may or may not work for the painter, shop conditions, etc. this is why a lot of guys will swear by a brand that a lot of other guys thinks is just crap. i personally am a fan of PPG, it fits my needs great, i have tried a few others... and always go back to PPG. this is just my personal choice.

.

[68protouring454]

i am with you guys, standox clears need to have at least a 5-10 min flash off, to get solvents out before baking, standox voc clear bakes for 30 mins at 140 panel temp, i have my booth set on 165 air temp to achieve 140 panel temp.
also the basecoats only need 15 mins flash off especially in a booth enviroment as they are air dry and any decent booth changes the air every 3-4 seconds, so there plenty of flash off happening, i have never needed to go more than 3 coats of clear, which were applied at one time.alot of guys using the thinner american clears will apply 2-3 coats, then block it flat with 1000 then re-clear 1-2 coats after 1-2 days to maintain the minimum film build to keep the uv protection there, as during the color sand the clear gets real thin

tnude, i am also a firm user of meguires hand glaze, or speed glaze applied by hand, when doing black i compound, the dual action clean (lighter paint safe polish) then go onto hand glaze to get rid of the nasty black swirls from wiping it down
jake

[zbugger]

Ok, wow... The last I don't know how many replies are so over my head it's not even funny. No way in hell I'm painting my own car...... Yet.

[evilzee28]

Originally Posted by race-rodz

im with frank on this one...... any problems with the reducer not evaporating would also tell me the wrong reducer is being used, not enough flash time, or some other kind of operator error.

as with almost all chemical reactions.... heat speeds up the process, so when the car is baked... you are speeding up the cure time but speeding up the chemical reaction. every tech sheet i ever read says to allow ample flash time before baking cycle.... so as to not trap any solvents.

as for most of the paint being equal nowadays....... i couldnt dissagree more. i try new products on a regular basis... and sometimes i find a product that suits my needs better.... maybe it goes on smoother... maybe it cures faster... maybe it polishes better. if they were all pretty much the same... then this wouldnt be the case. each "brand" has its own charateristics that may or may not work for the painter, shop conditions, etc. this is why a lot of guys will swear by a brand that a lot of other guys thinks is just crap. i personally am a fan of PPG, it fits my needs great, i have tried a few others... and always go back to PPG. this is just my personal choice.

.

Hi race rodz & 68pro touring454, how ya doing? it's good that fellow painters are able to give their hard earned knowledge to those that need it & hopefully help them to avoid problems with their own cars in the future. As you say, it seems a misconception by a lot of folk that 2K "cures" chemically & they aren't aware of the need to avoid solvent trapping.As to disagreeing with the comment regarding paints being pretty much the same,there are certainly some exceptions as I said, but the point I was trying to make was that on the whole they all have to meet the same critreria ie to be suitable to paint cars to OEM specs. As I said & I agree with you, once you find a product that suits you, stick with it.

[race-rodz]

im not a painter... i just pretend i know what im doing so i can charge lots of money to paint harleys

i never even heard of standox voc clear ... must be an east coast thing, somebody should send me some so i can try it out

[ProdigyCustoms]

Originally Posted by evilzee28

Hi race rodz & 68pro touring454, how ya doing? it's good that fellow painters are able to give their hard earned knowledge to those that need it & hopefully help them to avoid problems with their own cars in the future.

Yeah, I really appreciate you guy's agreeing with him also. I am hoping that some day I may know enough to do this for a living too. For now I will just continue to sit in class and take notes before I attempt to do this professionally. There seems to be so much to learn. The part I do not understand is the 3 week outgas stuff. I also do not understand, Are you saying it is a chemical process or evaporation process Evil? I notice in your first introduction post you refer to a chemical drying process, then just above you say "it seems a misconception by a lot of folk that 2K "cures" chemically", which is confusing the hell out of me?

[evilzee28]

Originally Posted by ProdigyCustoms

Yeah, I really appreciate you guy's agreeing with him also. I am hoping that some day I may know enough to do this for a living too. For now I will just continue to sit in class and take notes before I attempt to do this professionally. There seems to be so much to learn. The part I do not understand is the 3 week outgas stuff. I also do not understand, Are you saying it is a chemical process or evaporation process Evil? I notice in your first introduction post you refer to a chemical drying process, then just above you say "it seems a misconception by a lot of folk that 2K "cures" chemically", which is confusing the hell out of me?

Hi sorry for any confusion,if you re read my posting you'll see that it says.... "it seems a misconception by a lot of folk that 2K cures chemically & they aren't aware of the need to avoid solvent trapping".....Yes it does "cure" chemically but also by evaporation & the point I was trying to make was that most people aren't aware of the fact that evaporation also takes place & care has to be taken not to trap solvents, people think it just "cures" & that's it! I guess it's just that painters use words in their everyday speak that can be taken outta context if used literally.I get a lot of this when I take college class. The easiest way to try to explain this is:-......... before the invention of 2K paints, all paints had to have a thinners in them to reduce the viscosity (thickness) enough to allow it to spray outta the gun. Once the paint was sprayed it would take a while for it to dry or "cure" (cure is a word used but it doesn't cure in the true sense of the word, it's a painters way of saying dry ).The thinners in the paint would evaporate to the paint surface,which enabled the paint to dry. Drying times would vary dramatically between various products, so I'm unable to give specific times here.These paints are known as single pack type paints,cellulose, eurethane, lacquer or synthetic, all are air dry.

2k Paints or 2 pack paints, have a thinners & a catalyst, the catalyst speeds up the drying time dramatically, & the thinners is there to allow the paint to be sprayed outta the gun. Now this is where it can get confusing, yes, the catalyst does have a chemical interaction with the paint which allows the paint to dry quicker, but the solvents or chemicals in the catalyst need to evaporate.The thinners also interacts with the paint to allow it to dry (evaporation) so I guess if you really want to pick the bones out of it, both chemical & evaporation occur in the drying process not one on it's own. You can actually spray 2K without catalyst & it will airdry slowly & be able to be cut back & polished.The smell of a fresh paintjob is the chemicals/solvents evaporating & not the smell of the paint itself. Now to add more confusion,... the thinners you get to go into 2K comes in three types, slow standard & fast, which will speed up or slow down the drying time accordingly.Slow & standard can be used in a bake oven & the fast would be used for small blow ins or for a non bake situation where it dries in atmosphere without the addition of heat. So you see, the thinners affects the drying time also, which shows evaporation takes place

There are an awful lot of chemicals in the catalyst or hardener as it's known, the worst being Isocynates (cyanide based) which can kill you & cause cancer if you don't use proper air fed masks when spraying.Once the paint has been sprayed onto the panel the catalyst speeds up the drying time dramatically, but there are still solvents in the thinners & catalyst which need to be released to the paint surface. 2K paints surface harden very quickly & with the normal amount of paint sprayed ie 2-3 coats, there's never a problem with solvent entrapment (or outgassing as it's known professionally, solvents evaporating to the surface). It's only a problem if the solvents aren't given sufficient time between coats (flash off time) or if too much paint is applied. If this is the case, the solvents aren't able to get to the surface before the surface "cures/dries" & the solvents become trapped. When trapped they can be seen as very small white dots when looked at closely in the paint.With solid colour you'd be hard pressed to see them, but in a clear coat over a black or dark colour they become very visible.Obviously there's far more to it but hopefully I've explained the basics of what goes on. As I said, painters get into the habit of using words & phrases when talking to each other about what they're doing & if used literally can confuse others.I realise that maybe this stuff should have gone on the tech discussion pages, sorry 'bout that. Hope this has helped to answer your questions.

[race-rodz]

this is going nowhere........ when all else fails read the directions.