Help with Star S-106 Gun

[Dave_EH]

Hi,

I bought two new spray guns S-106 gravity fed in 1.7mm and 3.0mm nozzle.

I had two panels prepared for priming on saturday, and used the 3.0mm gun and they came up quite well with primer/filler.

I blocked the panels back ready for topcoat, and attempted to spray with the 1.7mm gun.

I couldnt get a good result at all.  Very much like an orange peel.  I tried to adjust paint flow and airflow for sometime, but couldnt get a better result.

I used a strainer to pour the paint in, and the gun also has a new filter.  It really spitting, hence the outcome.

Can anyone assist?

I think 1.7mm might be too large.  Star recommend 1.2-1.4

[Glenn 'Stinky' Stankevicius]

Is the paint thinned correctly? I know I stuffed up a paint job because of this 

[EffCee]

Dave,

As Stinky has said, it sounds like the paint needs to be thinned more, how much thinners are you adding? From my experience, depending on the type of paint, it may be necessary to add up to 50% thinners to get the spray pattern correct.

You need to try and find the balance between too thin and too thick, too thin and it will run everywhere, too thick and you have the orange peel that you describe. You need to be able to get it to the point where you can get it on so that it is nice and wet, with a nice gloss (assuming that you are using a gloss) without having it too wet so that you have runs and sags all through the paint.

If it is too thick, then you have an orange peel effect, or if you aren't putting enough on, it will look like it is a flat paint or maybe a semi gloss.

Keith

[Dave_EH]

I mixed it 50/50.  I thought that would be a reasonable starting point.  I might need to experiment more!

[Glenn 'Stinky' Stankevicius]

I think I had to go as far as Paint 25%/Thinners 75%, the result being very "watery"

[MattFC]

I had exactly the same experience with the same gun. I found that mixing about 60/40 with more thinners to be slightly better, as well as upping the air pressure a little. In the end though, I was still not really happy with the result so I ended up getting out my tried and trusted old Star 770 suction feed, while I'm no expert, it gave me a MUCH better finish. I've since spoken to a professional painter and he said that basically, gravity is better for 2 packs but even he prefers suction when it comes to acrylic. In fact, his gun of choice for acrylic was the Star 770 with a 2mm nozzle. ( I used the 1.6MM).

[Ed]

I mixed it 50/50.  I thought that would be a reasonable starting point.  I might need to experiment more!

your mix is 1:1

I have always mixed acrylic 1:1.5

try again at 1:1.5

I use a Star gravity 1.7mm fluid tip for acrylic.  I had to get rid of the inner filter before it would give good results.

Cheers

Ed

[Dave_EH]

Cheers Ed et al

Sounds like a working plan at least.

Interesting what you say about the filter.  I didn't use the filter on the 3.0mm gun, and it worked much better.  The instructions didn't mention the filter, it just came in the box!

If I am straining my paint through a proper paint filter prior to filling the gun, then I shouldn't really need it?

[FC427]

It's not a good practice to over thin the paint as it breaks the paints membrane down and it won't have a longevity with acrylic 1 to 1 is the absolute maxum  1.7 is to small from a gravity gun 2.2 works a lot nicer or go back to you suction gun and try again also play with your air pressure as some air caps need a little more .......FC427......

[Ed]

Mark,

I was just following the tech sheet which recommends 1:1.5 

can you recommend the best fluid tip for 2K gravity feed?  im thinking my 1.7 is too large.

my touch up suction feed gun seems to spray the best out of all my guns too.

Cheers

Ed

[FC427]

my touch up suction feed gun seems to spray the best out of all my guns too.

Cheers

Ed
[/quote]
Hi Ed gravity guns are made to spray a thicker viscosity [2K] I have found  the touch up gun with the 1 or 1.2 nozzle always spray finer than the full sized gravity guns but you must also take in to account that you are not trying to refinish the hole car with a touch up gun , just a smaller area .....FC427.....