|02-03-2013 01:06 AM|
|demarques_191||what kind of clear are you using? Is it being shot with humidity in the air (garage or outside) is it a forced dry clear or a air dry clear? ARe you using the right reducers/hardeners for the proper temperatures?|
|01-25-2013 05:37 PM|
1: take Barry's advice.
2: use SPI primers and clears and SPI base whenever possible and save some of your Looneys and have great results.
|01-25-2013 05:18 PM|
Just to add to "33Willys77", if the base would need to be sanded to achieve mechanical adhesion it would need to be rebased as well, especially if, as you mentioned, your spraying the car a metallic silver.
|01-25-2013 04:48 PM|
|33Willys77||I agree with 69 widetrack. 2 days waiting is not good. There are 2 types of adhesion - chemical and mechanical. If the base drys too long, you wont get the chemical adhesion, therefore the base would need to be sanded or scuffed.|
|01-25-2013 12:55 PM|
No1. With respect to letting your base dry for 2 days before top coating can be a problem as well. Flash times are important but to much flash can give you similar results as not enough flash time. Most major paint manufacturer's recommend clearing base coat with 24 hours of basing and maintaining a temperature of about 70 degree...If your temperature is warmer it would need to be cleared sooner. 2 days may be to much flash time and clear coat adhesion may be a problem down the road. There are so many variables as to how much base you but on will also affect the recoatability time....check your tech sheets.
No.2 Allow more flash time between coats of base...make sure that solvents have evaporated, especially if you have a low hiding color and need multipul coats of base for coverage...pounding base on to get coverage is a recipe for disaster and as BarryK mentioned, solvents coming out of improperly flashed base coat can and will cause your clear to die off or give you that hazy look.
No3. How much air flow have you got in the area that your painting in? To little air flow will cause your base to not flash properly in the manufacturer's recommended times...To much air flow will cause your base to appear to be flashed off when only the top has flashed and the solvents are still trapped underneath and will come out over a period of time after you have cleared the car and have cut and buffed it...you can also have a delamination problem with improperly flashed base coats, when the solvents in the base try to escape, they often take the cured clear with it.
So to answer your questions...lighter coats of base, more flash time between coats of base, make sure your air flow is proper and check your tech sheets for maximum recoatability times.
Hope this helps.
|01-25-2013 10:38 AM|
I think the air supply is ok i will add one of those mini filters to the gun next time.
I think my problem is to much base coats to get coverage. and not letting it dry enough.
that hand slick rule does not work for this stuff..
just a side note.. I was looking at the area I sanded and buffed today. and it looks like the first picture again.( getting fuzzy) this is so dum.
I am trying to think what I should do to correct this. was thinking to let dry a week then sand. hit new base coat. let dry 2 days then go to the clear. what you all think?
|01-25-2013 09:07 AM|
|33Willys77||Make sure you have a dry air in the hose when spraying and a good filter. Some high solids clear can actually trap moisture and air when being applied (very thick clear). Is the clear drying to fast? With the amount of orange peel, appears it may be drying too fast and the clear is not laying down flat. I have seen this with some Sherwin and PPG. I now use Wanda paint and I have superior results - plus I lay much more clear than most people do on a car because I am burying artwork. Make sure your flash times are correct - make sure the base is dry. Make sure your air pressure is high enough to atomize the clear.|
|01-25-2013 08:50 AM|
Southern Polyurethanes Inc
SPI has been mentioned a lot on this forum and I believe they have a canadian distributor now which makes it easier for you. Someone with more experience will chime in shortly Im sure
|01-24-2013 05:16 PM|
whats a good system to go with for clear these days?
hard to find in my area solvent based stuff these days
|01-24-2013 02:26 PM|
The last time I had this problem, I had used some PPG Concept paint that a customer had already bought. I sanded and buffed... but the orange peel and a couple sags came back!!!
I fielded the question about having the clear continue to shink over very long periods... and a guy who used only that system said to let it dry 2-3 months before i sand and buff!!! Screw that!
My own clear reaches a stable finish in 1-2 days, and never ever shrinks again! It might be the nature of your paint system, keeping it from being good for anything but force-drying... or requires a pefect mixture, ideal conditions, and flawless spray technique.
Personally... when a product proves to be too sensitive... I never use it again! }:-(
|01-24-2013 12:11 AM|
is this what we are talking about? I too have this problem
first picture is my problem
second picture is after a wet sand and buff
3rd picture 50/50shot
I am using the sherwin wiliams dementions base and clear.
this problem comes and goes for me. I am trying to narrow it down.
I am thinking to many base coats and not enough dry time.. first problem is the demensions base is so (water down) needs alot of coats to fill colour correctly.
I use to paint with the Sherwin Williams Ultra 7000 which was so great but can't get local no more. so working with what I can
after the clear is buffed etc I too see it come back to a little foggy after a week or 2.
base is mixed 2:1 and clear is 4:1 I am using a med hardner
temp inside is about 15c
its winter in canada so can't do much more in my paint room
|11-09-2009 11:42 PM|
Barry is right, most people rush to get the second and third coats on. What seems like 20 minutes of waiting is usually 5 minutes. You get rushed to get the job done and apply the next coat way to early.
The solvents (reducers) get trapped under the next coat and after 3 coats of base, that's a lot of solvent under there. It works it's way to the clear and clouds the clear. The next event will be delamination.
|11-09-2009 04:34 PM|
Yes those colors are the ones that cause the problems 99% of the time.
Remember, contrary to what the cut and paster moderators post on here (just a couple)
Humidity plays a big roll as to how fast the solvents get out, so when the humidity is high, it is very important that the first coat gets extra flash time.
A good rule of thumb is at 70 degrees 50% humidity or more first coat should flash 39 minutes.
Also with the blues and greens they tend to not cover as well and obviously if you now have 5-8 coats of base to cover there is a lot of solvents still trapped.
Worse part is when you see these contraction and hazing problems, they can also lead to poor shone chip resistance and or even de-lamination of the base, if solvents trapped in first coat or de-lamination of clear if just cleared to soon.
Water-base is even more critical.
|11-09-2009 03:21 PM|
i use 2k primer sealer yes with approx 10% or less solvent. I use 2k HS clear with no solvent. I use a mix of waterbase and solvent basecoat. Come to think of it, the last two colours i sprayed where this was apparent was a royal blue and black, both in solvent. I use the same slow speed reducer for everything.
The bonnet i did recently had a reaction with some previous paint and i had to dry flat this and spray the colour on really dry. I managed to get the colour on ok after about 10-12coats of real thin base, then cleared again with no solvent. The day after the hazing effect was quite apparent, probably the most noticable ive ever see it.
oldBodyman, your comments are the most interesting and i will definatly try leaving the base over night to see what happens!
|11-08-2009 03:47 PM|
|mitmaks||did you use 2K sealer? I was thinking maybe solvent in base/clear is reacting with body filler, etc underneath.|
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