[05RedKat600]

Got home tonight, started wet sanding. The one with wrinkles had soggy paint all the way to the primer in a couple spots. I'll get pics after dinner. I suspect it's because that's the side with the oil leak, and I didn't degrease well enough before painting. Paint scraped, wet sanded smooth, let's see what happens again! Just find it odd it didn't show until now.....might be due to the cold and slow cure times. Who knows.

[KatanaGSX92]

Wow. You sure are getting a lot of unexpected practice. Sorry you're having so much difficulty.

[05RedKat600]

Wow. You sure are getting a lot of unexpected practice. Sorry you're having so much difficulty.

Uh, yeah. Basically I had to strip both pieces last night as the first coat of primer was still gooey. Oy vey! Time to start all over again! No biggie, just time lost. I've learned quite a few things and there is no hurry to get it back on the road. Next time, I sure as hell won't be doing any painting in the winter!

[05RedKat600]

Ok, stripped, sanded, wiped down, and this time coated with brand new high fill primer. Much, much better this go around.

[Mojoe]

how long did you wait for the primer to cure the first time before you sanded and applied the base coat? if you put on two heavy coats (I think that is what you said), and with it being cold, it probably just didn't cure.

oh well, you are learning that is a lot to learn about painting. you know, there are 3 basic forms of "paint".

you have powder paint, more commonly know as powder coating and requires heat to cure.

then you have gaseous paint, which is what you are using. this means the paint is suspended in a liquid or solid form, in a gas that is sprayed onto the substrate ( a substrate is whatever it is you are painting). this type of paints needs sufficient time to cure, and does it by expelling the gas it was suspended in.

then you have liquid paint. it's just how it sounds....it's a liquid and is applied with a brush, roller or whatever. this type of paint have very little gas, sometimes none, and just "dries".

there is a difference between drying and curing.

so my guess...which is what it is, just a guess, seeing as I am not to actually see what is going on.....is that you did not allow it time to cure. it may have seemed like it had cured because you were able to touch it and it felt dry, and you were able to sand the surface. but in reality, under the surface, below the level you sanded, it still contained gas that was not expelled...aka: it was still wet. then you sprayed the base on it, and in a sense, you blocked in the gases, and this will lead to "mush".

here are the common failures in a paint job:

The main reasons of paint failure after application on surface are the applicator and improper treatment of surface.

Application Defects can be attributed to:

Dilution

This usually occurs when the dilution of the paint is not done as per manufacturers recommendation. There can be a case of over dilution and under dilution, as well as dilution with the incorrect diluent.

Contamination

Foreign contaminants added without the manufacturers consent which results in various film defects.

Peeling/Blistering

Most commonly due to improper surface treatment before application and inherent moisture/dampness being present in the substrate.

Chalking

Chalking is the progressive powdering of the paint film on the painted surface. The primary reason for the problem is polymer degradation of the paint matrix caused by attack by UV radiation in sunshine.

Cracking

Cracking of paint film is due to the unequal expansion or contraction of paint coats. It usually happens when the coats of the paint are not allowed to cure/dry completely before the next coat is applied.

Erosion

Erosion is very quick chalking. It occurs due to external agents like air,water etc.

Blistering

Blistering is due to improper surface exposure of paint to strong sunshine.

my guess is that you are having problems in the 2 things in bold. the cold weather is slowing down the curing process, and you are contaminating the primer with the base coat. yes...base coat can contaminate primer. if it isn't cure completely and you add other chemicals to it...ie: your base coat and reducer, you are contaminating.

my suggestion....don't even touch those parts for a couple of days. allow that primer to really cure. in fact, I suggest bringing them in the house with you and let them cure there for at least 48 hours just to be safe. under normal application, 24hrs for high build primer is sufficient, but you laid it on pretty thick, so give it 48. imho, that is probably the biggest mistake beginners make.....using a high build primer, then just because it feels dry to the touch, they assume it is cured....then you end up with a mess and can't figure out what went wrong. all because rushing it.

here is another little tip....depending on how cold your shop is, take a blow dryer to your parts before spraying. don't use it so close and get it so hot that you soften the primer, but try to bring it up to about the room temperature of your home.

I am betting you are making another error. you might be using a "general use" reducer. meaning it is good from say 50 to 80 degrees F. well if you shop is around the low end of that or less, meaning under 50F, it can take forever to cure. on the opposite end of the scale, if it's 100F outside, you might have to work like a road runner on acid to lay the paint down fast enough before it dries. with clear coat, that can make it very difficult to get a shine because the atomized clear is actually drying in the air before it hits the substrate. so in you case, you SHOULD be using a lo-temp reducer, which I don't imagine you are doing because most beginners aren't even aware of it.

anyway...some food for thought for ya.

[05RedKat600]

The bottom line is that I didn't not wait long enough for the first primer coat to outgas all the way, so the solvent stayed in the primer, and it was still gooey. I'm actually heating the parts, and the paint, in the house by the fireplace before I paint them now for better results. As I said way back when, I rushed it. This was not entirely unexpected.

[Mojoe]

well if it means anything, Red, you are not the only one who has made that mistake. even if they don't rush it, they misjudge how long high build or epoxy primer can take to cure...especially 2 thick coats of it.

the general rule with that stuff is once you have laid down that primer, consider your work day done and walk away and give it time to cure.

personally I never use the stuff unless I stripped it right down to the bare plastic, then I will spray the whole part with it. then I set it aside and don't touch it for at least a day, sometimes longer, depending on the environmental conditions.

If I am just spraying over the old paint, I don't use high build primer for two reason. 1st being is that it is "stronger" than regular primer. I mean this in the chemical sense...it's harsh, and because it is slower at curing, it can allow time for it to eat into the paint below it.

in short, high build primer should only be used on a bare surface...not over other paint. it is made to fill in imperfections say like on a motorcycle rim that has been casted, and you want a smooth finish. on paint you should just use regular primer, then spot putty the imperfection, sand smooth, then shoot with another coat of primer.

high build primer has it's place, and should not be used for everything. it can be used for everything, but it just slows down the process (time for it to cure), and cause headaches if you don't use it properly, in the wrong applications. in other words, if you do use it where you really aren't supposed to, you gotta know how to use it. that means one light coat, let it sit for a while, then re-apply. slapping it all on at once is just inviting problems.

once you do it often enough, you will get the hang of it and learn a few tricks. I have reached the point that I just use my nose. spray on some high build primer and then 20 minutes later pick it up and give it a sniff. it will have a strong odor. let it sit for 24 hours, then give it another sniff. you will find it is much less "potent" as the reducer or thinner has evaporated. it will smell like primer, and not a primer/reducer/thinner mix. but you ain't there yet, so just give it at least 36 hours :

[05RedKat600]

Yup. Primed Thursday night, sanded last night, might get around to shooting a gloss coat today. Not sure as the parents are coming down from Seattle and the in-laws are coming for dinner.

[Mojoe]

my suggestion would be to just leave it alone for today. spend the day in the house helping the ol' lady tidy up or whatever it is you have to do to prepare for the visitors and just let those fairing finish curing. depending on how thick you laid it on, and the temperature, it very well could use a bit more curing time. there is no need to rush it, is there?

[05RedKat600]

my suggestion would be to just leave it alone for today. spend the day in the house helping the ol' lady tidy up or whatever it is you have to do to prepare for the visitors and just let those fairing finish curing. depending on how thick you laid it on, and the temperature, it very well could use a bit more curing time. there is no need to rush it, is there?

Nah, it's hard as a rock. I dry sanded it last night, and it sanded up into this nice, fine powder so I know it's good.

[Mojoe]

well as I mentioned before, just because it feels dry and you can sand the surface of it, it does not mean it is cured. this stuff cure from the surface down. you know...for example if it is 40mil thick, the top 25mil may be "cured", but the bottom 15mil is not. spraying the base over it now could mean you are "sandwiching" the cured part in between, and it will just work like a sponge and suck up everything....and possibly leave you with some more mush. it's a crude way of putting it, but that is about the gist of it.

cured isn't even an accurate way of putting it. the surface might just be "dry", but none of it will be "cured" until....well, until it's ALL cured.

but regardless...seriously consider what I am about to tell you. DO NOT slap on a wet coat of base. doing so will only increase your chances of something going wrong. example....if you are aiming for say 30mil of base, don't slap on two coats of 15. instead spray 3 coats of 10, or 4 coats of 7.5. of course you won't be able to measure this...it is just an example. simply put, just mist it the first coat. give it a bit of time, then mist it again. you know..do 2 "half coats" instead of one thick wet one. this will decrease the chance that it eats into the primer.

and do not try to get your base coat to shine. it isn't supposed to shine. I think you mentioned how shiny it was....and it isn't supposed to be. base coats is supposed to dry flat, like a primer. if you end up with shiny base coat, you are doing something wrong, such as applying it too thick and wet.

[05RedKat600]

well as I mentioned before, just because it feels dry and you can sand the surface of it, it does not mean it is cured. this stuff cure from the surface down. you know...for example if it is 40mil thick, the top 25mil may be "cured", but the bottom 15mil is not. spraying the base over it now could mean you are "sandwiching" the cured part in between, and it will just work like a sponge and suck up everything....and possibly leave you with some more mush. it's a crude way of putting it, but that is about the gist of it.

cured isn't even an accurate way of putting it. the surface might just be "dry", but none of it will be "cured" until....well, until it's ALL cured.

but regardless...seriously consider what I am about to tell you. DO NOT slap on a wet coat of base. doing so will only increase your chances of something going wrong. example....if you are aiming for say 30mil of base, don't slap on two coats of 15. instead spray 3 coats of 10, or 4 coats of 7.5. of course you won't be able to measure this...it is just an example. simply put, just mist it the first coat. give it a bit of time, then mist it again. you know..do 2 "half coats" instead of one thick wet one. this will decrease the chance that it eats into the primer.

and do not try to get your base coat to shine. it isn't supposed to shine. I think you mentioned how shiny it was....and it isn't supposed to be. base coats is supposed to dry flat, like a primer. if you end up with shiny base coat, you are doing something wrong, such as applying it too thick and wet.

It's just Krylon lol. I have a paint gun, but it's too damned cold and dusty in there to do a job like that. I plan to sand the base, and then do another base coat to get rid of the crap in the paint.

Before I clear it, wetsand with 240 or 400? I also have 600 but I don't think there would be enough to bite to with that.

.

[Mojoe]

well I am not 100% certain what your response means, but regardless whether it is a spray gun or a rattle can. same advice still applies....go easy on the first coat of base.

[05RedKat600]

well I am not 100% certain what your response means, but regardless whether it is a spray gun or a rattle can. same advice still applies....go easy on the first coat of base.

Just seemed like you missed the fact I was using Krylon with all this talk of cure times, reducers, epoxies, etc. Wanted to bring it to your attention, that's all.

[Mojoe]

yup, I missed that, but the same principal applies. maybe even more so as rattle cans do not have the same amount of hardener mixed, in order to prolong shelf life, which means it is likely to take even longer to cure.

ok...now that I know you are using rattle cans, I am pretty much certain your problem lies in just not giving it enough time to cure. you seem to be doing everything else the right way, so that has to be it. going by the time frame of this thread, you are working at a "spray gun" pace. I have used rattles cans a few times and I always found them to take forever to cure, just because I am used to a spray gun application. I can apply clear with a spray gun and be water sanding and buffing it 24-36 after, under ideal conditions. never in eternity would you be able to accomplish that with a rattle can. in fact, you would be lucky to be able to grab a part without leaving a fingerprint or two behind.

so with it being rattle can primer, and high build at that, because it cures slower than regular primer, I would not be applying a base coat to it in anything under 5 or 6 days if the parts are left in the cold, and even then I would be nervous. if they were brought in the house, 2 days minimum, 3 to be sure.
I know it might seem like I am exaggerating, but I am not. my theory is easily tested.....pour a bit of high build primer (straight primer, no reducer or hardener) into an old butter dish or coffee can...not much, just enough so you can roll it around and imitate a nice "2 coats" on the bottom, then see how long it takes to cure. in a colder environment like your shop, I am betting it is still a bit gooey a month later.

so when you take in account the minimum amount of reducer in a rattle can in order for it to be able to sit on a shelf for however long, and the temperature you are working in, you really do have to let it cure longer. imho, at the pace you are going now, which is probably being determined by your gut feeling....well whatever you guts is telling you, triple it. just remember, you still have to clear it all afterwards, and you have to build up the clear fairly rapidly and it has to be wet in order to achieve the shine. this means you will be putting a lot of "pressure" on your work underneath, so you need to be 110% certain everything is fully cured.

btw, I have been there. nothing sucks more than to get your clear all laid on, happy as a pig in sh*t with the results, then come out the next morning to admire your work and find the clear eating into the base. thankfully it only happened on 2 parts out of all my body parts because if it had of been all of them i probably would have cried.....or smashed something. guess it would have depended on my mood at the time. so if it sounds like I am giving a bit too much input on the subject, well it's just because I don't want to see you end up there. I don't want to see anyone end up there. it is depressing, frustrating, and down right expensive when you have to keep starting over. so I just "stick my nose in" as much as I feel I have to in order to help prevent it. I would rather have you mad at me for butting in all the time than to see you have to keep starting over.