First time spraying , some questions

[sprint_9]

Ok, so I sprayed the rocker panels on my truck, basically a job to fix any major paint flaws and avoid significant rusting due to most of the paint starting to flake off. I went into the project not expecting great results, fist time I have used any type of automotive spray gun or paint, but I read alot on here and got alot of good experience with this project. One thing I learned was its very difficult to spray the rocker panels, especially the bottom side. With this I ended up with some orange peel in spots on the upper side rocker and then runs in a couple of others. Most of the runs ended up on the very bottom side of the rocker, most likely to me trying to lay it on to not have any light spots.

On the runs, Im guessing I was probably a little too close and a little too slow, would that be a decent assumption as to why the runs occurred?

The orange peel Im not really sure on, it was in a spot that I should have been able to do a little better, but it was still tight.

The gun I was using is a Warwick, 904. 110 psi at the wall, 25 at the gun. Gun adjustments, air on full, fluid out 2.5 turns, fan about 12 inches. Using Universal Clear.

Any input is welcome, fire away. Thanks.

 

[sprint_9]

If I follow this - A simple formula to remember is orange peel is fluid adjustment and run control is an air pressure adjustment. If you’re getting a few runs try upping the air pressure 5-10 pounds more.

I plan to up my pressure to around 28-29 at the gun, but what do I want to do for the peel, or at least try on my next project? Do I want less fluid or more, Im thinking less but am not sure?

 

[crashtech]

I will bump this to the top. Sounds like you are on the right track, but might just need more practice.

 

[bomccorkle]

Turning pressure up at the wall will help too. Start at 125 or higher there.

 

[BoostedOne]

I also never set my pressure that high at the "wall". I usually put my regulator at around 30ish, then fine tune with the cheater valve on the gun. The "regulator" that goes on your gun isnt a regulator at all, its just a needle valve that fine tunes the flow. So with the pressure jacked up at your wall regulator to 110psi in the line, you also have 110 psi at the cap which quickly drops down when you squeeze the trigger. Result as far as the spray goes is every time you pull the trigger you have a massive pressure spike then a rapid drop.

As far as gun settings go, about the only thing that many people can offer is rough pressure settings and fluid tips for different products. Tips are somewhat important. Too small and you obviously wont get coverage or it will be dry. Too big a tip and you wont have enough control. Other than that, it just comes down to personal preference.

When I learned(back in like 90 or 91) I was using old siphon guns like the Binks Model 7. Then I took a handful of years away from paint work and got back into it a few years ago(did plenty of body work, just never finished anything, LOL). Well when I got back into it I got a gravity gun. One of my friends who started learning at the same time but instead, actually stayed with it through the years as a career and a really accomplished all around body guy was my mentor even though it has to be by phone because we live so far away. I remember asking him.. "So, I keep seeing 'X psi at the cap'.. Just what does that mean? My gauge is on the line." His response "Meh, I dunno.. I don't bother with setting the gun to those sheets".. My response "Um, well..ok...umm.. what do you usually set your gun at when you spray?" His response "Heck, I dunno.. wherever it sprays best".

And thats just it. After using my guns several times, I couldn't walk out there and set all the needles to the exact spot and hand it to someone to spray with. I set my regulator to about 30-35 psi, pull the trigger and listen for a certain sound that I have found works for me. I then shoot a couple of test shots to set where I get a spray pattern and fluid amount that works for me.

And thats the other part of it. One guys settings that works awesome for him can work horrible for someone else. How fast you typically travel is a big factor. I like to set the gun where I travel fast. Another friend of mine sprays so slowo its painful to watch. But you can only go fast in certain places, so I modulate the fluid when I hit spots where I have to slow down to blow material in tight crevices and so forth. How wide your fan is also has a huge effect on your air pressure and fluid tip. If you shut the fan down into a circle, the cap pressure goes way up, and the material is heavily concentrated.

So like crash has said, you just have to practice more. If it was as simple as following a formula being a painter would be a minimum wage job. It takes some skill, some learning, and a ton of practice. Stick with it and you will find out what works for you.

I will say I hate doing rockers(atleast on cars since they are so close to the ground).. Only suggestion I can offer is be careful, and really watch what you are doing. Good lighting. But to me the rockers are one of the most challenging parts. For most people, it works out such that they get some experience doing panels with much better access so they get a feel for how the materials look when they are wet and whats going to happen by flash time and dry time, so they can know what to look for by the time they get to the rockers and therefore they can modify what they are doing on the fly.

- - - Updated - - -

Turning pressure up at the wall will help too. Start at 125 or higher there.

I got sidetracked when I was writing my post and this came in after mine... so..

Really?? Maybe I will learn something but why is this? As I mentioned if I have my wall regulator that high the pressure is just unstable, with that blast when you pull the trigger. Or is that something you want?

 

[sprint_9]

Thanks for the feedback guys. I agree that more practice is probably the first thing I need, on better/easier projects. Im going to paint my bumpers off of the same truck this or next weekend, that will be one opportunity to fine tune and try some things. Im going to the salvage yard in the next few days too, I may pick up a practice panel or two.

bomccorkle, I ran across the thread where it was discussed about the 125psi at the wall, I will try that next time I spray as well.

BoostedOne, you can get diaphragm regulators to regulate the 125 psi down to 30 at the gun, before it enters the gun. Here is the one I have for reference http://www.johnsonautobodysupply.com/Warwick-Spraygun-Regulator-REG-34H.html

 

[bomccorkle]

I run 145 at the wall and iwata diaphragm regulators. No pressure spike out of them. Also run diaphragm regulators off the tanks. I've never seen that burst of pressure with them although I have with the Chinese cheapies that don't last longer than a few weeks anyways.

I also run the air that's on the gun wide open, I'm not even sure what its there for.

I may be mis explaining(and I prob am) but the way I take it is your pressure at the wall is your amperage, and you gun reg the voltage, you need that force in your lines to keep the flow up as well as blast apart the high solid content, the higher at the wall the better luck I've had. The higher I run at the wall the lower I can run at the gun and the less over spray and haze in the air I have.

I am fairly ruthless with clear, I damn near pour it on, super wet slick coats and this method has worked the best for me.

If youre in a pickle you can always reduce the UV clear a smidge, 5-10% will help it flow out, but you also defeat the high solids of it at the same time.

Rockers are a real pita but what I have found is I put the car up as high on jack stands as I can and I have a light I set on the floor under the rockers as well, just having them all lit up helps a ton.

 

[BoostedOne]

Ahhhhh.. Well there ya go, LOL.. I never noticed small diaphragm regulators like that, just the needle valve types. Thats why I see the burst if I run too high a pressure on the main regulator.
IF you have one of those, then yes I can see the benefit of running the pressure high on the wall. That way you wont get a drop in pressure in the line when the trigger is squeezed. Thats why I set my wall reg in the 30s.. enough pressure so that when the pressure drop hits in the line it doesnt go too low, but not so high theres an initial blast from the gun.
I will have to look at some of those diaphragm regulators. Yall got me sold. They dont look much bigger than the needle cheaters that came with my guns.

As for the rockers, I personnaly wish I had the height to consider jacking up the car At 5'6, on many cars its already a toss up if I need buckets or walk planks to do the roof, LOL. Obviously I dont like to have to stand on anything when I spray because it just adds more potential for damage(stir up some dirt, plank/bucket falls/gets tangled in line, etc)

I recently picked up a Devilbiss detail gun. It doesn't hold much material but I wonder if hot swapping over to that would help(load both guns, shoot the rockers with it, everything else with my Plus) would be better. Thats one of my challenges is getting the gun down there in an angle where its spraying, and the airline isnt binding me up with the floor. The detail gun is way more compact. It even came with DeKups that I beleive are supposedly able to spray inverted.

 

[bomccorkle]

Ah yes getting high may be a problem for you, I'm 6'4" so I may have ya beat there. The diaphragm regs are the way to go for sure, motorgaurd and coilhose pneumatic both make some as well I don't thing there's any appreciable difference in size between the two, honestly I've been thinking of just pulling that air knob out of my guns and just putting plugs in them....

I use 3m pps cups when I get to spraying rockers or anything I'm moving around like a monkey, I've been thinking of trying out Tue devilbiss ez liners being as they are so much cheaper.

Also I add a swivel to the end of my line when I get ready for base clear as well, helps keep to hose bent out of the way.

 

[sprint_9]

I use 3m pps cups when I get to spraying rockers or anything I'm moving around like a monkey, I've been thinking of trying out Tue devilbiss ez liners being as they are so much cheaper.

Ive got a set of the ez liners I may try out when I do my bumpers this weekend, Im curious to see how they work.

 

[bomccorkle]

Cool beans. If you wouldn't mind would ya throw some feedback back at this thread when you give them a run thru?

 

[BoostedOne]

Ah yes getting high may be a problem for you, I'm 6'4" so I may have ya beat there. The diaphragm regs are the way to go for sure, motorgaurd and coilhose pneumatic both make some as well I don't thing there's any appreciable difference in size between the two, honestly I've been thinking of just pulling that air knob out of my guns and just putting plugs in them....

I use 3m pps cups when I get to spraying rockers or anything I'm moving around like a monkey, I've been thinking of trying out Tue devilbiss ez liners being as they are so much cheaper.

Also I add a swivel to the end of my line when I get ready for base clear as well, helps keep to hose bent out of the way.

Since I am a Devilbiss guy, with a Finish Line for Primer, a GTI, a Plus, and now the detail gun, my detail gun is the first gun I have ever owned that has a air control valve in it like you are talking about. The full size Finish Line, GTI and Plus dont have that adjustment but have the needle valve style cheater valve in the gun kit that attaches like the regulators you are talking about. With a cheater valve, small filter, and the airline fittings you have like 6" of fixed length coming out of the gun. I just figured on the detail gun(which was the first Devilbiss I bought that did not come with the cheater valve) all that valve you are talking about does is incorporate the cheater into the gun handle to make it more compact.
If you have a diaphragm regulator on your full size gun, just leave it wide open.

I have been considering adding a swivel on my gun like you mention.

Thats cool that coilhose makes the mini regulators. I went with them for my wall mounts and very satisfied.

 

[sprint_9]

Got some epoxy sprayed yesterday and today. Thought it went pretty decent, tried to focus on gun control and technique more than anything else, definitely made some changes and improvements from when I did my rockers. Had one small run where I got a little carried away going around the corner on my front bumper, need to do some sanding anyhow so no big deal.

bomccorkle, I tried to use my liner kit and could not get the insert to fit in my cup, tried my Vaper 2.3 cup and couldn't get it in that either. Not quite sure what to think on them, if its just my off brand cups or if the adapter just fits that tight. Going to have to look at it closer tomorrow or something, I tried to get it right before I wanted to spray thinking it would be no big deal, and of coarse it was.

 

[sprint_9]

Got everything buttoned up today, came out pretty good I think. I felt much more in control of things this time around and the results came out better because of it. I think bumping up the air pressure helped a ton.

Next go around Im going to try and get a better booth constructed, had some dust/dirt issues but nothing major, to be expected I guess. I got everything I wanted to out of this project, made my daily driver look a little better, and learned alot for my upcoming restoration. Thanks to all that helped me out and will help me out in the future.