I have been advised to shoot a tack coat, then a wetter coat and finally a full wet coat. Anyhow, I assumed that I controlled this by the spead I moved the gun. Is this correct? Or should I actually be dialing down the amount of fluid with the gun control?
jor

 

Yes, I would say control it with how you spray, and leave the fluid control alone. Unless they've changed them, Centari's label directions say to spray 3 full wet coats. You could spray the last one a little wetter if it looks dry after the second, but I wouldn't vary the wetness of the coats too much.

 

When I do my tack coat, I'll hold my gun a few inches further from the work. The idea is to just "mist" the surface. I don't try for a thin coat, just a real heavy dusting - to make it sticky. You should still see a little primer color underneath. I use the tack coat to practice my gun control. I might do a few "dry runs," just moving the gun and my arm with no paint. Just to see if the spray angle will work on this corner or that, see if the hose will reach or how to hold the hose so it won't fall in the paint, ect. Then spray the tack coat to see if my plan of attack worked. Then, hopefully, there will be no suprises when I do the heavier coats. Like door jams, corners and edges; the spray doesn't flow around corners. The tack coat is great for checking this out, because you'll still have contrast with the primer coat and can see what pattern is doing. I keep a big cardboard box next to the mix bucket and spray it a few times after filling the cup, just to get a feel for how the gun and paint are acting.

 

My apologies for hacking thru your post, but I only intend to help out the persons that are still developing their skills. So if I offended you, then" I beg your Pardon."

 

No offense taken.. Wrong choice of words on my part. I spent a lot of years spraying residential enamel with an airless. I used a big tip, big hydro and my rhythm was as fast as my arm would go. I'd never used a cup gun. When I used a cup gun for the first time, I had a problems like having gun too close to the work and tilting the cup upside down... Even now, it seems like not enough material is flowing and I want to open it up.

Agreed though, you want to keep the tack coat wet. How would I put it, like a fine splatter? Lol. We'll leave burying overspray dust for another thread.

 

FYI -- Another bit of information in case you didn't already know.

The Devilbiss OMX started the whole cup with a liner set-up. And now 3M markets a cup and liner system that will actually allow you to spray with the gun inverted. It works good on the lower lip of the wheel well, rocker panels and the such. It gives close to the same spray ability of a pressure pot system, but basically self contained in the size of a gravity feed spray gun.
Thanks, John A.

 

<cr>
For a quick and cheap gun liner, get yourself a bread sack.

Stuff the bread sack into the empty cup and line the interior of the cup. Carefully remove the sack so it retains the shape of the cup. Fill you cup 1/2 full and carefully put the sack back in. Put the cap on. You can now spray upside down.

 

This must be a process when using a suction style cup gun. Right?
And when it is upside down the breather hole might make you mad as the paint drips out of it. Both systems I refered to are gravity feed guns. I would not recommend bread sack method with gravity feed guns, sounds too messy and bread sack will slow the paint flow.

 

Actually, all I use is a gravity feed HLVP. It doesn't make sense but it works.

 

If it works then it has to make sense. If it doesn't make sense then it doesn't work. So how does the paint travel from the confines of the bread sack, and into the spary gun inlet? When you say bread sack I'm envisioning a pleated plastic sleeve open on one end and just a little larger than a loaf of wonder split top buttermilk. Is this about what you are referencing? Have you seen either of the two types I refered to? they are Devillbiss OMX (disposable liner system) the other is 3M's #6001 cup w/ #6000 lids and liners. These two have two different ways of releaseing the paint from inside the plastic disposable container and into the spray gun. Is the bread sack similar to either one of these? Not to say you are wrong but I just don't undeerstand.
John A.

 

<cr>
I've seen the OMX but not the 3M. Haven't used either one.

Yupe, that's the bread sack. Picture a inflated condom.

I haven't done a whole lot of experimenting with the setup. I was told only fill the cup 1/2 full and that's all I've done. Don't know how it would work filling it more than that. I suspect I would go with an OMX or 3M if I was doing a lot of overhead painting. It's a hassle to set up but for those quick jobs, the price is right.

 

After re-reading your first post a-la cup liner. I think the thing the plastic bag does is to prevent the paint from falling out the cup vent. But you would have trouble with the gun spraying cause the paint would fall all around the sides of the bag and the center of the bag would be drawn in or at least towards the gun inlet. (when inverted) And this is not giving you the real advantages of the other liner systems. They are: When the bag empties, and collapses, the gun just stops spraying. It doesn't spit or sputter it is just done. And the best part is when you are done, turn off air supply or unplug, invert gun and pull trigger to release what paint is in the fluid tip and inlet. This paint flows back into the liner. then pop out the liner and dispose of it. The only part of the gun that is in need of cleaning is the inlet and the fluid tip & air cap. 1 or 2 oz. of solvent will throughly clean them and your good for the next round.

Now I have been told the OMX is no longer offered by Devilbiss, the gun never took off with most painters who never used one. They do still sell all the parts to keep them repaired. If I could change the OMX the only thing that I don't like is the fan control. Devillbiss tried to make it adjust from full fan to no fan in just 1/4 turn of the **** and it makes the smallest change in the **** make a huge change in the fan pattern. Then the **** is a little loose and it can move a bit without you even touching it. I would give it a half turn from none to max. and I would put a detent on it so it clicked from each step up the range of adjustment like maybe 10 different fan settings that stay put till you move them. And I haven't seen any other gun with the dual trigger system, that is the best part about the gun to me. It allows you to hold the gun perpendicular to a horizontal surface while spraying. Even a pot gun can't do this without the painters wrists being pressed into an unergonimic position. And no one will hold it that way for long. I have a Sata RP and NR 2000 Mini Jet, but still prefer the OMX.
Good Luck
John A.

 

<cr>
The gun liners are nice, with clean-up being the bigggg plus. If I was going to be spending a large amount to time painting upside down, there is no doubt I would invest in them. As it is, an occassional under the dash job doesn't justify the expense and the bread sack fits the bill.

That's interesting about the OMX. Amost bought one. As I recall, they had an adjustable nozzle size, besides the fan control. The liner also caught my eye.
Dennis