Another "how do I fix this"

Question about blending over spray.
Since I'll be blending the base coat on a horizontal surface, I anticipate a lot of dry over spray on the rest of the hood. How do I deal with this prior to clearing?
thanks
 
Question about blending over spray.
Since I'll be blending the base coat on a horizontal surface, I anticipate a lot of dry over spray on the rest of the hood. How do I deal with this prior to clearing?
thanks
Excessive overspray should not be an issue. If you have lots of overspray you need to adjust your gun correctly and your air pressure. You should tack between coats of base though, to remove any oversoray that may be on the surface.
What gun are using for the basecoat? One of us here can more than likely give you settings to start with.
Also make sure you use a high quality reducer. Preferably SPI reducer. Slow or very slow. Low quality reducer will result in dry rough overspray outside the blend area. High quality reducer solves that. Remember too, do not use fast or medium reducer. Only slow or very slow. (SPI 885 or 895)
 
I'm using a DeVilbis Finish Line, not a 2, 3 or 4, but the original FLG with a #3 HVLP air cap and a 1.3 tip and I'm spraying at 22 psi with the trigger pulled. DeVilbis states that 23psi is the maximum but 22 seems to work best. For the last coat of base I've reduced the pressure to 18 and pulled the gun back. I'm also using it for clear.
Tomorrow, I'll check the reducer that the paint jobber gave me with the Wanda base and let you know what it is. It's not SPI
 
I'm using a DeVilbis Finish Line, not a 2, 3 or 4, but the original FLG with a #3 HVLP air cap and a 1.3 tip and I'm spraying at 22 psi with the trigger pulled. DeVilbis states that 23psi is the maximum but 22 seems to work best. For the last coat of base I've reduced the pressure to 18 and pulled the gun back. I'm also using it for clear.
Tomorrow, I'll check the reducer that the paint jobber gave me with the Wanda base and let you know what it is. It's not SPI
The 23psi is just to get the 10psi at the air cap that's required by the EPA. You can go higher to meet your spraying style. Most people do bump it up several pounds.
 
The paint supplier sold me Collision Pro reducer and I have used it in all the base I've applied to the car.
I also have SPI Urethane Reducer.
AAE. Thanks for that information. I did not know that. I'll have to try that when I spray the clear.
 
The paint supplier sold me Collision Pro reducer and I have used it in all the base I've applied to the car.
I also have SPI Urethane Reducer.
AAE. Thanks for that information. I did not know that. I'll have to try that when I spray the clear.
Use the SPI all that other stuff is good for is cleaning your gun. It's the low end stuff that I hate and causes people issues. You will notice a difference I promise.
 
Starting the work tomorrow. Wish me patience and good luck.
Thanks for all the advice.
 
This can of worms just will not give up.
Last Monday afternoon, I sprayed epoxy primer on this spot as sealer waited 2 hours then sprayed base over it. However, it was obvious that the filler was not done correctly so I wet sanded the filler down like it should be, used waterborn wax and grease remover followed by solvent wax and grease remover. Waited 30 minutes (shop temperature in the 90s) shot the sealer and you see what happened in the photos so I wiped it all off, along with all of the base that I had applied, using urethane reducer and called it a day, figuring that I hadn't allowed enough time for the W&G remover to dry. Today I sprayed the epoxy sealer and got the same result. What the hell?
I know that I'll have to sand the filler off and start again because the filler is obviously contaminated but anyone have an idea as to what happened.?
Just a little info, the filler where this occurs just doesn't feel smooth like it should even after wet sanding with 800.
IMG_2501.jpg
IMG_2502.jpg
 
I'm confused about sanding filler wet. Filler is porous and will absorb water, so if it gets wet, it has to dry for a long time before primer. But even if the filler is not wet, it's totally normal for the filled area to look different because it will absorb solvent from the primer. It's not really advisable to try to seal and paint directly over bare filler for this reason. Filler must be primed and sanded before sealing and painting.

It's really hard to tell from the photos, but if that is bare filler with a coat of epoxy over it, it may not be anything alarming, it just appears to show the different solvent absorption rate of the various materials you are primering over.
 
yes could be what crashtech says...and yes filler has a lot of talc in it and soaks up water...i think i would sand that down smooth in that area before digging out filler (unless you really think it didnt cure correctly). and apply a couple coats of unreduced epoxy over any bare filler let it cure ..block it smooth and if you didnt break thru any metal or filler spray base....and i would also give about an hour for w&g remover to dry in high humidity....and another thing when sanding off that rough textured area...i would put it in the sun a bit so if theres any moisture left in the filler it will dry out.. there may be some better advice on it coming so hang in there!
 
After taking these photos today I wiped it all off with urethane reducer instead of letting it cure and then having to sand it off.
Water and solvent trapped in the filler makes the most sense. It looked just like the epoxy was beading up on the surface of the filler.
 
Could 3M dry guide coat trapped in the surface of the filler have caused my problem?
The reason I ask is that after 8 days of drying in 90 plus daytime shop temperatures and 72 hours under a lamp to keep the surface at about 120, I went out wiped the area down with solvent, then waited 3 hours, in 90 degree temp and very low humidity, I sprayed epoxy primer, not reduced, and got the same result, beading of the primer on the surface of the filler. Grrrrrr!
Today, I sanded out the problem area filler, refilled the area, sanded to 320 then rubbed the dry guide coat on. That's when it hit me. This could have been the problem. I had been racking my brain trying to figure out what had contaminated the surface of the old filler and when I rubbed the guide coat on, the filled area took on the same mottled appearance of the old filler.
I've since sanded the area with 400 and will wait overnight before spraying primer again.
I've used this guide coat throughout this project and never had a problem so I'm still puzzled.
Any thoughts?
 
I guess it could ...but I don't know why you would guide coat bare filler...I normally guide coat after priming. With 2k...spi epoxy you almost don't need a guide coat with the sheen it has...I would sand that filler area till all of that guide coat is out... which you may have to refill....if you're not bald now you maybe after this project..lol
 
It's not the guide coat.

I get the feeling that you may be mistaking something fairly normal for a problem. In addition to being porous, filler can have "micro-pinholes" that can give a very textured look to the first coat of epoxy. Epoxy does not like to bridge even tiny holes. It will usually flow over micro-pinholes after the second coat, though. Depending on the filler brand, a full skim of fine putty and light sanding might be necessary to eliminate micro-pinholes.

I could be wrong, but without taking some really hi-res photos, there's no way to tell.
 
Thanks crash but if you look at the area around the "beading up" area, you can see that the epoxy went on just as I have seen it do throughout this project. However the beading up, just like sweat on a glass of ice water, is something I have not seen before.
Tomorrow, I'm going to try it again and if it does the same thing, as apache said, I may have bald spots where I've pulled my hair out. LOL
 
Yahoooooo!. I just sprayed the first coat of epoxy and it didn't bead up. Preparation and Prayer ;)
 
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