I am in the process of trying to respray a car. I am using ss acrylic urethane (restoration shop) with my gun (Iwata lph 400) 1.4 tip and orange cap, The manufacturers recomendation is up to 1 quart per gallon for reducer, At that ratio i was getting a whole bunch of orange peel. The paint was coming out of the gun way to thick. Thinking maybe it was just trying shoot the single stage acrylic urethan with that gun was just not the ticket. I brole out the old devilbiss siphon gun and had the same problem tii i added a bit more reducer. What is the best way to get the viscosity correct when the manufacturers recomend isnt working? I was amazed how much more material the devilbiss uses. It will be nice to get the iwata figured out
I had a similar situation with the Croix turbines where I kept getting orange peel. It was PPG single stage. I called the vendor maybe three times and each time he would say add more thinner. Later on I talked to my buddy Bob at the paint store and he said the same thing. So dump most of the cup out so not to ruin it and add a little thinner at a time until you get it to flow. Gun distance is also a factor. Hope this helps
If you are getting a lot of orange peel with the manufacturers recommendations then all you have let is gun set up and application. I always look at it this way when a rep comes in and shoots paint on a demo, does he make up stuff and keep it a secret? Nope, he shoots it using the manufacturers recommendations he is working for and then shows the painter at the shop the same thing because it WORKS. He doesn't tell the painter at shop to make up stuff, you know what I mean?
You don't have enough air volume at the gun or something, something is not breaking up that paint as it comes out of the gun.
a 1.4 should give you good results with SS. consider the speed of your passes, temps, gun distance, and of course reduction. how hot was it when you sprayed? ideally you want 74 degrees and this is the number all manufactures go by according to my knowledge.
That is a hard one because if you don't have a proper air supply you don't know. Going by the gun manufacturers numbers are as close as you can get, it usually has a "max pressure" on the gun, this is to legally be an HVLP gun with the proper transfer efficiency it has a maximum inlet pressure. Going by that or a tad higher is the closest you can get. I say a tad higher because if you have a poor air supply with small pipes, with restrictive filters or couplers you can have pressure but not volume. So once you get the thing opened up your pressure drops because there is no volume to keep it up.
I have 5 coats on right now. I guess ill scuff it all with 400 and try again. would 2 more coats be ok? I dont want it to thick. What do you guys recomend?
if I just colorsanded and buffed would 600 or 800 be to abrasive to start with? I was thinking with that much material i could knock it down aways with 400 and spray 2 coats and call it good.
tomorrow is another day. I'm not a professional painter. But I do remember that some of these paints called for five coats. I have used 600 and 800 to initially knocked down the orange peel, I to have grown oranges in my time.There are many pros on this board and I'm sure you'll get it straight. Maybe a suggestion. Don't paint the car until you get it right at the gun, just a thought.
I decided to turn on the radio and patiently sand her down a bit. I also am going to try to get the gun issue straightened out on a few extra doors i have aroun here. I can try a few different reductions and gun pressures. Obviously something I am doing wrong.
4:1 means 4 parts color (paint) to 1 part "HARDNER"(not reducer)
Some brands mix the hardner and reducer together so you dont need to get a whole gallon of reducer and 3/4 of a gal goes unused but some dont...those will say 4;1:1 the last number is usually reducer.
In a perfect world of painting (a painters paradice,LOL) You can stick with the directions on the can (manufactures "recomendation") but for most of us (every day,real world painters) without the luxury of a climate controled paint booh,or a paint booth at all...we all know when it gets too hot we need Slower reducer and when we are using the slowest reducer and still its going on a little dry we need MORE reducer usually just a bit more(a cap full) to a full to a full gun cup will do it.
once it gest passed 100 degrees you may have to do other things to get it to go on like glass...
What does your activator say Slow med or fast??? or even extra slow...
After reading DBM's post I took a minute and looked up the tds for that product. As DBM said 4:1 is 4 ounces of paint and 1 ounce of au 4001 hardener. Adding a reducer is optional.
My question is what are you using? What numbers on the cans? Have you read the TDS for each one?
10 @ the gun is measured at the air cap, takes a spendy test rig to measure it.
With your Iwata I would try around 16 -18 to start with, then start cranking it up.
With hvlp the amount of air flow is almost as important as the pressure.
Air pressure at the regulator on the air compressor 100 psi, regulator at the gun 16 for a start, hi flow couplings, no filter balls at the gun are 3 easy steps to get headed in the right direction.
At the gun use a regulator , not a flow valve marketed as a regulator.
I'd step back and take a good look and see what is wrong instead of shooting more $$ at it. You will figure it out.
Unless Single Stage has really changed over the years, I always mixed it 50% and then added the hardener and it would lay down smooth with no peel at all. Now mind you, that's been a few years back, probably more than I care to realize. I also always used a DeVilbiss siphon type of gun, and 60 lbs pressure. I actually don't think I ever had any peel with any of the single stage paints I shot. Also the last coat, I would thin it a tad more if it was a metallic and give it a final spray to eliminate any possible tiger striping.
Yep you are right, that was YEARS, we are talking decades ago. You best not try that today unless it says it on the tech sheet. Loading up the paint with reducer is a sure way to have some killer die back!
I picked up a viscosity cup yesterday. I can not find on the product anywhere it gives the seconds. The gun howver says 20 sec. on some of the gun info. With the paint with no reduction or hardener the paint is 35 sec. Does 20 sound like a reasonable starting point? I have a little extra material so I am going to figure this out on a couple os old doors I have around. I have the reg at the compressor set at 100 and the air hose i use is the standard shop hose that looks to be about 1/2 od. the regualtor at the gun is a good rti reg. I bought at the same time I bought the gun. Ill get it figured out. The reducer I am using is a medium reducer and the temperature about 70........Steve
Also with that gun is 6 in. a good distance for shooting from?
I am sorry Steve, I used a viscosity cup every single day 35 years ago shooting lacquer. I have not used one nor owned one in 25 years. With todays Urethanes you mix them as the tech sheet says, and that is IT, end of discussion for me. 6 inches is too close for most applications, but that distance is really all about the appearance of the product as it goes on and no one can say a hard and fast distance, it changes around the car for that matter.
Check to see if theres a screen in the cup,if there is toss it and try again...but it sure sounds like the paint is to thick to me...
6-8 inches for gun distance is perfect for me with a 50% overlap but I move very fast, everybody has to find there own sweet spot.
Has your paint been opened and sat for a while??? how about the hardner has that ever been opened?
paint and hardener brand new with no screen. I came up with the 35 number with unreduced uncatalyzed paint as just a starting point. I have a bit of of extra paint and a few body panels to dial it in with. I am going to try to reduce it to 20 sec and see how it works. I just dont quite understand why 4 1 1 still created such orange peel. The learning curve is frustrating but ill get her figured out......Steve
Who cares, mix the fresh paint and fresh hardener and spray spray it. Let it flash between coats. It is better to have orange peel than runs. Sand the orange peel off, This is in the clear coat. I use 1500 then 2500 wet sanding, then I use the 3M stuff to buff, polish the paint.
finally got the orange peel sanded out. Sux to make that much work for yourself. I did have a couple of edges and 1 high spot of metal that I did sand through. Very small. I have a few small parts to spray and I am not sure if I would be better to spray some color on the sand throughs when I do the small parts, let em set overnight then put the final 2 coats on or spray some sealer on the spots as directed. What say you guys? I really need this one behind me
If you have bare metal spots it's always a good idea to use some type of rust deterrent product like an Epoxy primer or even an aerosol etch before you apply color...just for that added protection and insurance, no matter how small the burn through.
The smaller parts will also give you a good indication of your gun set up to eliminate the orange peel. If your mixing your paint 4:1:1 with the proper temperature dependent reducer/hardner, your gun is set up properly as to pattern and air pressure and your painting at the proper distance, the orange peel problem should be eliminated.
I guess Ill be sprayin a small amount of sealer on these smsll spots. A bit more work but at this point ohwell. I did talk to a tech rep at iwata and he really suggested using the silver cap for single stage. It jogged my memory to remember i got the erange cap back when I was doing some metalic bike tanf
That paint last I knew was the Valspar 800 series and a high solids paint but easy to spray.
With the LPH gun you always use the silver with any clear coat or Clear and the purple for base, not sure where the orange fit in as I bought one when they first came out and i could not make it work for anything, so gave it to a customer.
Assuming its a 1.4 tip here are the adjustments and it should lay like glass:
Air regulator at the wall must be min 120Lbs for 25 ft hose, I have mine around the 150-165 lb area and just switching systems will cause me to readjust gun spraying the same HS.
Fan adjustment, wide open and turn in about 5-10%, so gun does not blow out center.
Fluid start at 2.5 turns out and you may need to go to 2.75 out.
If a 1.3 tip go 3 turns out.
Air pressure at the gun, set your regulator at the gun WITH trigger pulled at about 22lbs to start and you could end up as high as 32 depending on the piping of your system.
The air adjustment on the gun must be wide open when you are using a regulator at the gun.
ALSO this gun is made to spray 5-6" away from panel, 8" and all you are going to get is dry over spray and peel.
Make sure the internal strainer in gun is NOT there, give it to someone who you don't like or throw away.
With this adjustment, lay one wet coat, let flash and do your second and you should be done.
It is indeed a 1.4 tip. Thanx very much for the settings. I am going to spray a couple test panels (old doors). I really dont want to go through this aagain.....Steve
I guess the internal strainer is the little screen between the cup and gun?
Spray a test panel even if its just the back of a reducer can to get adjustments.
If still a problem call me with gun in hand, it won't take five minutes to fine tune.
If you txt me 30 minutes before you are about to paint I will watch for call and stop answering the phone, so you don't get voice mail.
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