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PostPosted: Mon Sep 26, 2022 12:35 pm 
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I feel really good about the finish on my latest, but I'm always interested in improving. One of the areas I'd like to improve in is setting up the spray gun. Do either of Jeff Jewitt's finishing courses offered through Robbie O'Brien's site spend a decent amount of time on this?


Last edited by James Orr on Mon Sep 26, 2022 6:08 pm, edited 1 time in total.

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PostPosted: Mon Sep 26, 2022 5:29 pm 
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Location: ottawa, ontario, ca
First name: Mike
Last Name: McNerney
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I have the levelling, wet sanding... course and it is excellent. It's been a year since I've looked at it but It assumes you can spray. But Jeffs book spray finishing made simple, comes with a dvd and it goes in more detail, like how to use turbines or compressors. I bought that 5 year ago and have been spraying furniture and guitars with the emtech WB products and it taught me a lot

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PostPosted: Mon Sep 26, 2022 5:47 pm 
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James—

Same as Mike. I think Jeff Jewitt’s courses on Robbie O’Brien’s website are excellent. But if you want basic gun adjustment, I recommend looking at videos by car paint guys and/or model painters on YouTube. I’m trying to get better at gun adjustment, too.


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PostPosted: Tue Sep 27, 2022 8:48 am 
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Brazilian Rosewood
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Assuming you have a decent spray gun - one that can be adjusted reasonably well and holds the adjustment, you may find that improving the "off the gun" finish depends more on "adjusting" the finish to suit the environmental conditions you have to spray under.
The finishers I have worked with who do need to have a high quality "as is" finish usually have a preference for the type of spray guns they use, but then modify the finish material to suit the equipment and the conditions by using thinners, reducers, and retarders as appropriate. I think that is where most of us fall short in our knowledge base.
I'm certainly no expert, and as long as I can spray a full wet coat without a lot of contamination or overspray I don't worry too much about the final surface - I am going to be grinding it down with sandpaper and buffing it out. I met one amateur finisher who restored old cars. He got beautiful results applying acrylic lacquer with a brush and buffing it out, much like we do a guitar finish. No expensive equipment, no spray booth, minimal PPE. It was where he found joy in finishing.


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PostPosted: Wed Sep 28, 2022 11:59 am 
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Thanks for the feedback, guys.

I feel comfortable spraying and buffing. The finish out of the gun was actually really good on my latest. I just get what seems like a lot of overspray, and I’d like to feel more confident adjusting the gun since I have two with different tip sizes, etc.

I also watched the teasers for Jeff’s new sanding and buffing course! It looks fantastic. I’d love to take it. :)


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PostPosted: Thu Sep 29, 2022 1:28 pm 
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James--

Any information I give about spray finishing is necessarily basic, because I'm not an experienced sprayer, but the following helped me a lot in my recent attempts to get better at this:

1. If you keep a mini-regulator as the last thing before the spray gun, you can keep the air to the gun at the setting recommended by the spray gun manufacturer. Since changing the other two settings (fan and fluid) can affect this setting, it is good to check and adjust the air setting every time you make changes to the other two.

2. I keep a roll of contractor paper on a jig I built; it dispenses the paper onto a flat vertical frame attached to the jig, which goes inside my benchtop spray booth whenever I am adjusting the settings on my spray gun. The best way to check spray gun settings is to spray some scrap paper or cardboard in a single spot and look at the spray pattern. This jig gives me a continuous supply of paper for such tests. Since the paper is brown and sucks up paint, it easily shows when it is wet with clear finish. That's hard to see with white paper.

3. After the air setting (which, again, should be at the manufacturer's recommended setting for the gun), the fan control is the next easiest thing to set. You know how big your particular gun can make the fan, and how big you actually want the fan to be for this project. After the fan, set the fluid, but re-check the other two along the way, because they all affect each other. Re-check in the same order (air, fan, fluid). Eventually, after spraying enough of the contractor paper, the spray pattern looks pretty good.

4. During this process, be aware of the distance of the gun from the project. One trick I have heard about for determining the right spray distance is to hold your hand in front of the spray gun, spray it with air only, and listen to what it sounds like as you move your hand closer to or further away from the spray gun. Starting from over a foot away, bring your hand in toward the gun. When the sound changes, that is the right spray distance.

Like I said, pretty basic stuff, but it has been helping me get better. Good luck with fighting the overspray.



These users thanked the author doncaparker for the post: Barry Daniels (Thu Sep 29, 2022 2:15 pm)
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PostPosted: Fri Sep 30, 2022 10:42 am 
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This is great. Thanks, Don.

One of the areas where I struggle is being able to see when the finish is beginning to atomize. Is that a splatter, or is that a mist? :)

I like the idea re. the roll of paper. I tend to keep large cardboard panels, but a roll of paper would be significantly more space-efficient.


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PostPosted: Sat Oct 01, 2022 9:28 am 
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James--

Here are a few photos of the paper dispenser, inside my spray booth. Because of the size of my booth, I cut about 8 inches of width off the roll of contractor paper. That's easily done on the bandsaw. I thought about fancier ways of holding the paper on the frame, but the large black Acco paper clips work as well as anything, and this allowed me to keep the build fast and simple. When they get gross with finish, I will toss them and get new ones for free at my office. The construction is basic: just some plywood sides and base, a poplar frame (a halved dowel on the bottom, to smooth the path of the paper), a dowel for the paper roll, and some Kreg joinery.

Attachment:
Paper dispenser front.jpg


Attachment:
Paper dispenser left.jpg


Attachment:
Paper dispenser right.jpg


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