Painting Advice Please Jotun and Lechler Epoxy and Cellulose

[JonnyAlpha]

Hi;

I have had answers to most of these question in bits a long while ago but just need to refresh my understanding.

I have spray the underside of my Mini with Jotun 87 some of it was done a year ago (under the main floor) the most recent was done a week or so ago (under the front arches.

I am no about to spray the inside and outside of the car, the inside was part bare metal and part original paint. The bare metal was rattle canned with U-POL Acid Etch to stop it rusting a couple of months ago and the original paint has been flatted down.

I have an FMT 3006 LVLP Gun with 1.4 and 1.8 needles / nozzles (FMT4007 Kit)

My recent epoxy came out a bit wavy / dimpled possible because the pressure was to high?

Questions:

1. What do I key the Jotun with ready for spraying on U-POL gravitex Stonechip and then celly top coat?
2. What tip should I use for the Lechler Epoxy 1.8mm?
3. 10% or 20% thinners for the Lechler when spraying
4. Is the thinners ratio for cellulose 1:1 i.e for 300ml of paint I need 300ml of thinners?
5.What pressure should I have at the gun for spraying the Lechler?
6. What pressure should I have at the gun for spraying Cellulose?

I sprayed Jotun and the Celly successfully some time ago and remember I had some trouble getting the pressure correct but never wrote down my setup!!!

I am running a line from the Compressor to a second regulator and then a short line to the gun, I may change this slightly this week by building a water trap using copper pipe but then a short line will run from the compressor to the water trap inlet and there will be another regulator at the water trap outlet, then a longer line to the gun from the garage to outside (about 10m)?

What pressure should I set the main regulators at the compressor and at the end of my main line before the line to my gun, I understand that there will be a pressure drop dependent upon the line length?

I am using these Spray Gun Pressure regulators which seem to be a nightmare to set, when I pull the trigger the needle does not stay steady and shoots up to 90psi?

 

[optima21]

I am using these Spray Gun Pressure regulators which seem to be a nightmare to set, when I pull the trigger the needle does not stay steady and shoots up to 90psi?

those arn't regulators, they are just restrictions to airflow, so if you have them fitted you'll need to release the pressure in the airline using the spray gun trigger before operating the needle to allow the paint to be sprayed.

you can set the regulator up on the compressor just above your working pressure at the spray gun, which you can check by using the gauge on the gun after using the trigger for a few seconds to get the airline to normal working pressure, as it will drop when the trigger is operated.

regulators like these can be bought cheaply, although you'll pay nearly as much again for a pressure gauge that has a more suitable range (0-60psi or 0-30psi)

http://www.ebay.co.uk/itm/281882414196

as you can see it doesnt end up being much more bulky than the "regulator" you have

 

[JonnyAlpha]

Thanks optima21

Any one help me with the rest:

Questions:

1. What do I key the Jotun with ready for spraying on U-POL gravitex Stonechip and then celly top coat?
2. What tip should I use for the Lechler Epoxy 1.8mm?
3. 10% or 20% thinners for the Lechler when spraying
4. Is the thinners ratio for cellulose 1:1 i.e for 300ml of paint I need 300ml of thinners?
5.What pressure should I have at the gun for spraying the Lechler?
6. What pressure should I have at the gun forspraying Cellulose

 

[RaceDiagnostics]

Here is what I do, but I know close to nothing.

1) I cocked up my gravitex today, I will use raptor in future, I would key with 240ish
2) I used a 1.8 for it today.
3) I used 10% and a ford cup and its viscocity was ok at 20degC today.
4) I have never used celly.
5) I sprayed with 2bar.
6) ..

 

[123hotchef]

those arn't regulators, they are just restrictions to airflow, so if you have them fitted you'll need to release the pressure in the airline using the spray gun trigger before operating the needle to allow the paint to be sprayed.

you can set the regulator up on the compressor just above your working pressure at the spray gun, which you can check by using the gauge on the gun after using the trigger for a few seconds to get the airline to normal working pressure, as it will drop when the trigger is operated.

regulators like these can be bought cheaply, although you'll pay nearly as much again for a pressure gauge that has a more suitable range (0-60psi or 0-30psi)

http://www.ebay.co.uk/itm/281882414196

as you can see it doesnt end up being much more bulky than the "regulator" you have

View attachment 85042

I just brought one of these and it don't seem to be functioning correctly turn it down and it just leaks air out all the time that cant be normal can it

 

[optima21]

on some of the cheap regulators there may be a small leakage of air, but I guess how good the seal on the valve is in the regulator, unless its a loose air fitting