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4000 Universal Clear Assistance

I sprayed some Universal clear today, and first time with my LPH400LV. So fairly inexperienced with this sort of thing. I learned alot but would like a little input on some various topics.

For starters here are some of the specifics on how and what was sprayed.
-4000 Clear, with 1/2 medium and 1/2 slow activator
-Metal temp 70 give or take a degree or two. Right after I was done clearing I checked with my temp gun and it was 73 on the rocker.
-LPH400LV, silver cap, 125 psi at the wall, 30 with with trigger pulled. Fluid started at 2.75 out, and worked up to 3.5 out, then back into 3 for my last coat, Fan in one turn from full.
-4 coats of clear sprayed, with a 30 min flash between coats, a little longer 35-40 min between coats 3-4. Fan off after fog cleared.

To start off, I think I was moving too fast and too far away, 6in, on my first 2 coats. On my 3rd coat I slowed down a little and that helped, but still at 6in or so out. Between my 3rd and 4th coat I searched for some LPH400 tips on here and found that I was probably out too far on my fluid, and holding the gun a little too far from the panel. So I went in on the fluid and held it closer, Im thinking I was now holding around 4 inches. That seemed to help alot, but by that point I had some texture from my beginning coats.

Given all of that is there anything I should do different? I think spraying all coats like I sprayed my last is a good step in the right direction.

Where should I go from here? If I sand with 6-800 and then work my way up from there to 5000, and then buff will that be good? Or should I sand with 6-800 and coat with clear a couple more times? I have the standard amount of lint or dirt in it as well. Thanks.

Inside the booth this kind of shows the texture I have.

Outside the booth in the shop it looks alot better, but the pictures make it look good.
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It looks kinda dry, the fluid probably needed to stay out, passes needed to overlap more, or travel speed needed to be slower as well as staying closer, which you did. Usually when I see clear like that, it's not thick enough to buff, but if you say there is four coats, there might be. If it was mine to do, I would sand it and re-clear it to make it look better and to insure against buffing through during the sand and polish stage.
I agree, I didnt mention it but Im sure my over laps could use improvement especially on my first coats. I feel like by 4th coat I had settled down a little, payed more attention, slowed my travel speed, and came in closer to the panel.

Physically I put 4 coats on, but the way I sprayed it compared to how you spray, or how it should be sprayed, is two completely different things. So in all reality there probably isnt 4.

Im with you on sanding and recoating as well. Ive been reading for the better part of the night and that looks like the direction to take. What grit would you recommend for sanding? And when I recoat how many coats, 3? Ive been reading about flow coating as well, I have a quart of retarder and thought about trying a flow coat as my last coat this next go around, probably not crazy buy maybe 10% retarder?


Paint Fanatic
Staff member
It looks really good for your inexperience!
Leave the fluid adjustment at 2.75 to 3 but only mistake you made other than that is no matter what you do you will never lay the clear right with that gun over 6" away.
I tend to be with those setting on that gun about 5" away.
Also with that clear, it is about impossible to reflow the first coat of clear if dry spray.
1500 wet till slick and buff. It will be sweet!
Ill try the 1500 and see how it comes out. Im not really out much other then a little time, and if I decide to recoat I will probably give it till Sunday anyhow as the temps here have plummeted but are forcast to rebound a little. So I have time to play with.

Barry thanks for your help via text yesterday too, here is a picture of the spot I was asking you about sanding base coat on. Ive actually asked you quite a few questions on this one spot over the last few days and it came out great. Without you and everyone else on the forum, past and present I would be lost.

I like the fluid at 3 turns out, PSI at 26-27 with trigger pulled (just till is starts to make that hissing sound) and like the others said, stay about 4" from the panel.
I don't add reducer until the last coat so as to reduce the chance of runs but that is a personal thing.

All in all it is looking very good. IMHO
Yes I think the main cause of my trouble was being too far away. It's amazing that a couple inches makes such a difference, but it really does.

I think I'm heading in the right direction. Id like to pull it out into the sun and look but it's highs in the 20's the next couple days
I know how that is, I can be pretty grumpy myself. Especially now that winter is setting in.

I focused on the passenger side of the roof, Im learning as I go so being a little cautious sanding as I havent done much of it. Buffing Im a little more comfortable with as Ive done 5 or 6 vehicles with good success. I bought a bunch of new supplies from chemical guys and have been very happy with it, alot better then the meguires I used to use. Shine had detailed his buffing process in a thread and following that worked very well.

I have alot more to do, but it looks very good.
The good news about putting it on a bit drier is that they'll be less urethane wave. As long as the mil thickness is there you'll be fine.
Bingo, Crashtech is the winner.

If we're doing insurance work, she gets 2 coats and its good to roll. If were doing a big time resto or a wide body conversion on a Porsche, well basecoat, than the next morning well lay 3 or 4 coats of clear, wait a day or 2, block it down and reclear with 3 coats. Than another round of blocking, than the entire finishing process starts. pretty much any color change or exterior paint job gets that treatment.
After a lot of thinking I decided to block down what I had and shoot 3 more coats on the entire cab. My main reason for this is I have some light spots in my base that I want to fix, and since I have more than 1 spot I decided to do the whole thing vs. a blend. Im glad I decided to go this route, it has been a lot of work to get it flat, but in spots I had kind of a mess to be honest. I really had some peel inside my cab on the inner roof, I have no headliner so this will show. I really would like a slick coat on that part so I dont have to try and buff it, sanding upside down is hard enough.

I plan on shooting clear on Tuesday, so today I pretty much finished blocking. Monday night or Tuesday morning I plan on scuffing with a grey scuff pad.

In the mean time I have a question regarding a break through. Barry told me not to break though and of coarse I did. I was trying to get some dry spray off from underneath my drip rail and right above the windshield and broke through on an edge. This is the only place I broke through and Im not sure what I need to do with it, does it need sealer and then base, or will just base work?
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