FINISH 101

[tippie53]

it has been a while since we got many questions on finish work and I want to bring you up to date on what I have learned.
I cannot stress enough the importance of prep work. I don't sand past 220 grit to allow some tooth for the finish to hang on to. If you sand too fine you burnish the wood and you loose that mechanical hold. This is often the cause of many adhesion issues.
So here is what I do.
A after sanding Seal
I use shellac or vinyl sealer depending on the finish I am spraying. I use 2 brands of lacquer. I stopped using sherwinn williams and use minwax and Mowhawk. I use the gloss and satin.
Now hear is where we get more technical.
The mix and application. I am using a Fuji Semi pro 2 sprayer with turbine. I also have 2 conventional spray guns but haven't used them for a while. I will be breaking them back out.
I will tell you that technique is as important as product. You have to work with the material and find what works for you. So I use a basic mix. On shellac a 25% thinned spray.. The one thing I can tell you is play with different needle sizes.This is what determines how much material comes out and the size of the droplets. I have a 1.3 in my gun and ordered a 1.0 to see how this will work.
So lets talk about mixes.
A use a filter to screen the finish before and after mixing. I like to use a small amount of retarder and thinner on the sealer. Mowhawk sealer 5 to 10% retarded 20% thinner . I use 2 coats then level sand and apply a filler. I use 2 fillers.
https://www.lmii.com/pore-fillers/3033- ... 16-oz.html
https://www.lmii.com/search?controller= ... sed+filler
I used to use pore o paq and will if I need to but the advantages of these are time as they dry in 40 min and you can get 3 coats in a day . You can also hit the sealer at the end of the day if you can give it a good hour dry time. They build pretty fast.
Once filled and sealed I do 3 coats of sealer the a light level sand with 400 grit. Then after sanding I double check to see I am level and ready for finishing.

this is my sealing process.

[Morecowbell]

John - thanks for posting this. One of the things I'm curious about is the HVLP vs conventional sprayer comment, was wondering why you haven't used the conventional one for a while but are going to break them back out - does that have to do with overspray and fumes that will now be dealt with by the new spray booth? The HVLP stuff seems a lot easier to deal with. Thanks

[tippie53]

I want to have the guns set up for water sealer and finish
I do like the HVLP fuji Semi pro.
The advantage to multiple guns is going to be needle size. I won't have to change the needle. I may get more guns for the Fuji Semi pro. The big advantage is no water infusion. On the compressor guns I need a water oil separator on line from the compressor. The turbine system doesn't have that issue but there isn't enough pressure to work the other guns. Even though they are HVLP they work different than the turbine.
I will be posting more in the near future. I have plans to shoe the entire finish processes both photo and video.

[Stray Feathers]

Perfect timing John - I bought a used Fuji Mini Mite 3 and Fuji gun from a friend and will try it out in my first attempt at spraying Mohawk lacquer. I don't have a spray booth so it has to be outside in a spray tent. I'll be watching for tips. Bruce W.

[tippie53]

ok
did you get thinner and retarder?

[Stray Feathers]

In anticipation of a Covid-19 lockdown, I bought Mohawk instrument lacquer, grain filler, and vinyl sealer. The sales person said I did not need Mohawk thinner, and sent another brand. I did not buy retarder. I did buy a respirator.

[tippie53]

ok them do at least 1/3 thinner to finish you can go up to 50%