Mike:
I just wanted to give you a quick update on how much use I have gotten out of your advice on spraying finishes.
First, in the "get to know your gun" department, I have now sprayed about 4 gallons (yup, FOUR) of paint through my little Binks 115 knockoff. I have sprayed a lot of different items with it, but I am proudest of the way my doors are now coming out. I actually know enough now that I can diagnose what I am seeing on my piece of sheetmetal (my gun setup/test medium) that I use to set the pattern/flow and can now adjust and change the gun to what I need. I have been having a blast with the Japan drier, and while I haven't actually ruined a finish yet, I have made the gloss go to satin, which is a sign of too much drier. So now I know my limits on that. I am at about 1oz of Japan drier plus one oz of thinner per quart and it works great on 70-75 degree days. I will certainly be toning that down for our hot summer days.
As for flow, pattern, viscosity, and pressure, I have the most well protected piece of plywood you can imagine in my backyard by my shop. I don't know how much different materials and mixtures it has on it, but they all dried up and it is now thoroughly plasticized. I have taken some of oil base materials I had left over on one of my jobs (the industrial stuff I am using starts catalyzing the moment it is opened to air, and it not good even in a sealed container after about 10 days) and tried all kinds of mixtures and settings.... all at 6 ozs. at a time.
I have found that my 2hp compressor is the one to use to shoot finish, as the one that is just a little bit smaller is painful to use. Like when shooting latex on doors, I like long unbroken spraying to spray the entire door side without stopping. Even with the little gun, it strains it just a little. But the 2 hp is perfect.
After the last exchange here, I decided to buy some urethane and set the gun up on my piece of plywood before getting on the doors for my client. I called them and moved the date to refinish, and got busy with the urethane. I used the Deftane Satin that I got from my local paint supplier and then went onto the Deft site to get the info on thinning. It couldn't have been easier. Still mixing in the gradient marked cheap sports bottles I have, I was able to measure out and thin exactly according to their specs. I was surprised when I started my practice runs as I had to turn the pressure all the way down to about
35 lbs since I was getting fog at 45. I was thinking it would take a little more air than that.It just wasn't needed. After I got the handspeed and gun position down, it worked great. I was glad I shot a quart up on the plywood because I was getting it too wet, and I had sags. I put the halogen lights on it where I could see the reflection when it was wet, and then adjust to about 30% coverage on the next pass (instead of the tried and true 50% for oils and spray can stuff) and it worked like a champ.
The instructions said they were looking for about 3 mil wet finish (!!!) and that it would dry to 1.5 mil. To me, that seemed really thick for one application (especially vertical application), but in the end, it is their product. So I followed you cue and sprayed one coat, then another about twenty minutes later, just when I could see the material starting to change from looking really wet. Worked like a big dog!
So out to the job. I stripped, sanded as needed, cleaned that nasty 15 panel door up and let it have it with the Defthane. I have to admit... I was a little surprised.... the doors turned out great. I mixed up a couple of different colors of gel stain for the door to match the interior trims on the house, and the match was good. And with the Defthane on it, the door turned out like a million bucks. And I was SO damn thankful I didn't have to brush that damn door. The door took about 8-9 hours to dry before hanging, but with the heavy coat on it, it looked totally sealed, and my client was thrilled. I hung it that night around 7 or so, and I was finished with the job.
I can't make enough money finishing doors to just do that when I go out for repairs and installations. But I CAN do well for my door installations, etc., if I can install and finish the doors for people since I can get them coming and going. And it is easy enough to set up and spray a door and go finish more repairs in the house while it is drying, so that make finshing a good thing. I just reinstall whatever I finished/refinished before I walk out for the day.
Since all the new construction around here has sprayed oil on the metal entry/garage/rear doors, people really want to see that on their new doors that they purchase from the lumberyard I am affliliated with since they see their new doors as new construction. And I don't care how good a brush man is, nothing looks as sleek and clean as a sprayed door. So I think there is a demand there, but I am still looking into that. And of course, I can just add this to my toolbox of things my company does when I am out on a job and someone says, "hey Robert, do you have anyone that can refinish my cabinet doors/garage door/bathroom door/bookcase?"
Next on the gun trials: lacquer. I have an amigo that swears by the "Old Masters" brand, and I will try to coax some out of him. I can't see spraying lacquer on one or two doors, though. I use Deft lacquer for interior doors and just pad it on. I use a disposable pad, and pitch it when I am through. Too easy to do it that way, and Deft lacquer is so forgiving it is almost foolproof.
BTW, here is the gun I finally settled on to be a companion to the little wannabe Binks:
I just thought you might be interested to see how things went since you were so generous with your time and suggestions. Both were a big help to me. And for me, I always wonder what happened later when I have taken the time and made some effort to help someone out. A follow up seems like a simple courtesy to me, and certainly a sign of appreciation for the help. This is mine.
So anyway, how you doin'?
Robert