Ok so I went out this morning to paint the jambs on my car. I got quite a few runs in the paint. It is single stage urethane. I did some searching on here and I think I know where I messed up but I want to run it past you guys and see what you think. I only did 1 coat. I will fix the runs of course before going farther. 1. The panel temp was only 52 degress which may have slowed down the flash time and allowed the paint to run. 2. I was try to put on to wet of a coat instead of fogging it and doing multiple coats. 3. I was moving the gun to slow which allowed the high build up and runs. 4. A combonation of all of the above!!! Any advice before a continue would be greatly appreciated. This is only my second time applying paint. I am using a Sharpe Finex with a 1.4 tip. Thanks as always, Todd
52 degrees will not work.Sand out runs and get the shop warmer.Put on a medium coat first then let it flash.Second coat can be heavier. Get the shop temp warmer.At least 70 degrees. Mike
Here are my observations re your paint. 1. Panel temp is a little low if only doing a jamb and do not have heat use a heat lamp to warm a little first and turn it off before you spray. 2.It is necessary to apply a fog/tack coat to get some tack for the next coat to stick. It does not look pretty but it is the correct way to do it. Apply fog wait 10-15 mins then apply wet coat. Apply following coats in 15-20 min intervals. Having gun too close and moving too slow causes excessive build up therefore runs. 3. You can apply coats in different directions overlapping them at 90 degree angles. Ensures total coverage. If spraying a metallic I finish with a top coat of single stage holding the gun at a 30 degree angle and fogging it on while the previous coat is still wet.
Skipping the first fog coat is the surest way to runs. Especially with all those crevices. Sometimes you can get away with what you did on something like a hood. Just not a jamb I'm not a pro but have painted a lot of stuff at 53 degrees, yeah it's low but use a fast reducer and be prepared to live with a little texture/orange peel in the paint. Extend your smoke breaks between coats to 2x-3x what they would be at 90 degrees.
Since this post is two hours old, you're probably out on the garage trying to fix it....but I'll bite Grab up some clean rags and some lacquer thinner and just wash off that first coat of paint---I'm serious...just wet a rag and start at the top and start wiping it down. Change rags frequently, and keep them damp.(wear gloves too if ya got em) It will take LESS time to clean it all off and start over than it will to wait for it to dry, sand runs, pre-clean, tack, blahblahblah Sounds counter productive, but what's your time worth?
Earl is right.... still cold enough and not set up enough to just wipe off, alot quicker. I once had a fellow call me doing a 58 Impala in single stage urethane and tell me it wasnt drying....... I asked you mixed it per directions right? Right amount of thinner and haedner right? Then i hear in a low voice... "hardner?" I tell him to soak a rag in Laq. thinner and tell me what was happening..... he says... "oh no it just wiping right off! what do I do now?" Keep wiping i tell him
I painted it a 8 am it is now noon. I had to go to work but I am home now. I will go and try the thinner thing. On the runs if nothing else. Thals to all who replied. Like I said it is all the errors I made coming together at once I think. Live and Learn Todd
Fog coat or tack coat is key. The rest of response's is right on. Your spray patteren is important too. Over lap and pressure for such a confined area must be adjusted as well. Relax, go in with confidence. Let us know how it goes!
Thanks Slammed. I think that the ROOT of my problem was that I rushed. I new I had to do a Tug job at 10. So I got up early to paint. I was more worried about getting it done than getting it done right. Lesson learned. Todd
Todd, what paint system did you end up going with? Spraying a single stage urethane at that low of a temp can be done but you need to use the fastest reducer and hardner available and an accelerator along with good technique. If you used normal temp hardners and reducers the film will dry but not cure until it gets really warm for quite a few hours. Trying to recoat the single coat you applied will usually cause it to wrinkle and lift like old enamel. Faster thinners and hardners will give you more control at lower temps and you will need to add an accelerator to speed the cure below 70 degrees. It's not very good to spray at low temps but it is possible. 52 degrees air temp would still make the metal lower than 52 degrees. You were probably at the low limit to get it to work using fast reducer, hardner and accelerator, and it takes a little more experience with the products to get the mix to work chemically. Let me know what you are spraying and I can give you a recipie for spraying the jambs and small parts in cool weather. overspray
All is not lost, look at overspray's sig. Words to live by my friend, write it on the wall. In response to your original post; your right, it is a little cold but with the right reducers it is definitely doable. Don't try to fog all 3 coats, youll end up blotchy and dry. Fog the first, but come in with a wet pass on the next 2. You can move the gun slow, most times you might need to on a jamb, but you just need to watch your trigger pull. Listen to oversrpray's advice, he'll get you on the right track and across the finish line.
Don't feel bad...from what I experianced, painting is a very touchy process. I had to paint the back of my cab 3 times. First time it was blotchy, spraying single stage urethane (pearl, never did it before), second time these mysterious craters appeard. I mixed in some leftover paint I put in the refriderator to save( too damn cheap to toss it) I yhink that was part of the problem. Started again today, sanding and re-spraying. It looks much better although it's a little orange pealy. Hopefully I can buff it. So what I'm sayin is don't feel like the lone-stranger, painting ain't easy. Hang in there.
always mist your fist coat and alsways keep tip of gun perpendicular to panel starting off of the panel and letting go of trip off the panel, keep spraying consistant. i 've painted in very cold weather and it dry fine with out runs.
Thanks again for all the replys. Overspray, I am using Kirker single stage eurothane. the color is Hot Rod black (satin-flat) finish. I was using medium reducer which probably didn't help. I shot the panels with a IR thermometer and the were 52 deg. By noon they were almost 70. I used a razor and got most of the runs. I was planning on using 320 and 400 to get everything smoothe and then give it another try. I will do a tack coat, WAIT! and do a medium/wet coat and see how it works.. Todd
The 1.4 tip on the gun is pretty universal but probably should be set with less fluid and a smaller pattern with a little lower air pressure for doing jambs. Watch the "King" then reset the gun with less fluid-smaller pattern and lower pressure, then shoot some test passes on paper. http://www.jalopyjournal.com/forum/showthread.php?t=225633&showall=1 http://www.kirkerautomotive.com/html/technical_center.html They have some tech and trouble shooting tips on the site. They show 2 hardners for the hotrod black-one is slower then the other. Check which one you have. They have a faster reducer. overspray
Well good news. Yesterday afternoon after digesting all the good advice from you guys I went out and got rid of all the runs and feathered everything in. I had another tug job this morning so I didn't get to do anything till about 3:30. Thae air temp was in the high 70's and my panel temp was 76. I shot a tack coat. I did it like I was shooting guide coat before sanding. I then waited about 15 min. and layed on a good wet coat. IT CAME OUT GREAT!!! I can't thank all of you enough for you help. Regards, Todd
Good deal, glad it worked out. More than half of painting is knowing why certain screw ups happen and how to rememdy them for next time. Anyone can mix paint, load it in a gun and lay it on. The book knowledge is what makes a painter sound.
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