Things went TERRIBLY WRONG

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Posted: Fri Mar 29, 2019 5:09 pm

typically if your product is going on rough or your getting orange peel you'll want to turn up the air pressure, just 2-3 # to start with. sometimes it can be cured by turning the fluid down but not by much, sometimes its a combination of both. your fan also plays into this somewhat. if you still can't get it right then you have the wrong sized fluid tip for the viscosity of your material. the basics of it all is that you want to have a good spray with the least amount of air press needed. to much air press. can waste paint and a lot more than you think.
Jay D.

they say my name is Jay

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Posted: Fri Mar 29, 2019 5:57 pm

badsix wrote:typically if your product is going on rough or your getting orange peel you'll want to turn up the air pressure, just 2-3 # to start with. sometimes it can be cured by turning the fluid down but not by much, sometimes its a combination of both. your fan also plays into this somewhat. if you still can't get it right then you have the wrong sized fluid tip for the viscosity of your material. the basics of it all is that you want to have a good spray with the least amount of air press needed. to much air press. can waste paint and a lot more than you think.
Jay D.

That’s probably what happened when I sprayed the hood the first time. Although I did spill quite a bit, I didn’t think for one second I should have ran out of paint when I started the 2nd coat and ran out. There’s no way y’all can tell how much I spilled, but I’ll tell ya, it sure didn’t seem like I should have ran out so quickly. Meaning, I believe the pressure was up way too high. I’ll tell ya this, my garage was very very cloudy and took a while to get the overspray out. Lessson learned!

I’d still like to know what those numbers meant on my last post? Anyone care to explain them?

I’m just a squirrel, trying to get a nut

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Posted: Fri Mar 29, 2019 10:01 pm

NewPainta wrote:Notes taken on all accounts. Especially the thinner and fine tuning the gun. I plan on shooting the bc with the 1.5 and clear with the 1.3. I did buy some more paint after spilling so much, and plan on testing, testing, testing the gun(with paint) before shooting the bc. If 1 drop falls out that tip, I’m bailing until I figure it out.
Unfortunately I’m leaving town this weekend and won’t be able to shoot most likely until next week. Maybe Monday afternoon when I return from my trip if I grow a pair and get the nerve to try again. I just don’t wanna rush things. Y’all know what will happen if I rush it.
I am feeling a little more confident with the gun now that i played with it a little more, even though it was thinner. I was able to fine tine it and at least get that to stop and spray correctly.

I did have one question though. On my tech data sheet it says exactly this

Spray Pressure
Conventional
Gravity Feed 25-45 PSI at the gun
Siphon Feed 30-45 PSI at the gun
HVLP 8-10 PSI at the air cap

That’s exactly what it says on the Nason Ful-Base Basecoat (IF quality)

Now I’m positive the Devilbiss FLG4 is a an HVLP gun, and it says to spray at 23psi, but the TDS says “ at the gun” and “at the air cap”..... So what exactly are they saying here? One says one thing, the other says another thing. Now again, I will test before I spray, but am curious as to what they’re suggesting??

ok just to confuse you a little more it looks like that gun need around 13 cfm at 23# at the gun I assume. that's a lot of cfm and needs a good sized compressor. you'll need 3/8id hose and fittings. think of cfm, if water was air and you had a 3" fire hose and a 3/4 garden hose and both were 35# pressure the fire hose will move a lot more air, cfm.
Jay D.

they say my name is Jay

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Posted: Sat Mar 30, 2019 2:44 am

NewPainta wrote:...I’d still like to know what those numbers meant on my last post? Anyone care to explain them?

You need to start with the tip range from your material’s TDS - usually a range like 1.2 to 1.4

So I grab my gun which has a 1.3 tip. Now I look up the guns suggested air pressure at the gun (not at the air cap which is for manufacturers to show compliance) and my gun’s instructions tell me some number such as “26 psi” so I start there and see how it works. Since I am a rookie, I only make small adjustments on one thing at a time.

Another total different gun tells me to use 1 Bar, so I set my pressure to around 14 psi with the same material

Sent by the random thoughts from the voices in my head...

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OldFatBald OldFatBald's Profile E-mail OldFatBald No Turning Back Posts: 776 Joined: Tue Oct 17, 2017 10:06 pm Location: I live in a house Country: USA	Posted: Sat Mar 30, 2019 2:51 am That FLG4 with the #3 cap is an HLVP, start with 23 psi for BCs and 26 psi for clears. Switch to the #1 air cap which is a conventional cap and you need to crank up the pressure to just under 40 psi These are ONLY for that particular gun. Sent by the random thoughts from the voices in my head...
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OldFatBald OldFatBald's Profile E-mail OldFatBald No Turning Back Posts: 776 Joined: Tue Oct 17, 2017 10:06 pm Location: I live in a house Country: USA	Posted: Sat Mar 30, 2019 2:54 am Find and watch the online videos on how to clean your gun - And DO it! I use a squeeze bottle and acetone. Sent by the random thoughts from the voices in my head...
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Posted: Sun Mar 31, 2019 8:20 pm

NewPainta wrote:I’d still like to know what those numbers meant on my last post? Anyone care to explain them?

Air cap pressures and inlet pressures are two different things. An HVLP gun will have an air cap pressure much lower than the inlet but since it needs a special tool to measure then the inlet pressure is the one that's usually used. 23psi at the inlet will translate to about 10psi at the air cap.

Chris

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'68 Coronet R/T '68 Coronet R/T's Profile Board Moderator Posts: 9893 Joined: Fri Oct 20, 2006 12:40 pm Location: ARIZONA	Posted: Mon Apr 01, 2019 10:10 am As stated above, that gun requires a large volume of air. What is the CFM output of your compressor? All the adjusting in the world isn't going to increase the volume of air to the gun. 1968 Coronet R/T ACTS 16:31
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NewPainta NewPainta's Profile E-mail NewPainta Settled In Posts: 51 Joined: Fri Mar 15, 2019 8:42 am Location: Ft Worth,Texas Country: USA	Posted: Mon Apr 01, 2019 12:07 pm OldFatBald wrote:Find and watch the online videos on how to clean your gun - And DO it! I use a squeeze bottle and acetone. Done! Watched every single video on cleaning YouTube has I’m just a squirrel, trying to get a nut
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Posted: Mon Apr 01, 2019 12:10 pm

'68 Coronet R/T wrote:As stated above, that gun requires a large volume of air. What is the CFM output of your compressor?

All the adjusting in the world isn't going to increase the volume of air to the gun.

I have a Quincy 60 gal 3.5 hp that puts out 14.4cfm at 40psi. I hope to God that’s enough since I waited forever to get it. I also just installed all high flow couplings on both ends.
One concern is I do have a 50ft hose. Which seems pretty long from what I’ve read.

I’m just a squirrel, trying to get a nut

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