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Normally I sand the finish when there is more than 24 hours between spraying. Sometimes, in my rush, I forget the sanding. For the eye it makes no difference in the end. And I know that some builders think that the melting-in capacity of laquer on laquer does not require the sanding.
Does anyone here skips the sanding?

Herman

within 24 hrs i won't sand but I will do a 25% thinned mix with 10% retarder . I spray a coat every 45 to 60 min for 8 to 10 coats , it isn't what you put on , it is what you let on. I want about a .016 to .020 green build cure off then flat sand to about .006 and do 3 thinned finish coats for a good flat base to shine up on

John,
Without specific tools, how do you measure the thickness?

My strategy is simple: earlier projects I sprayed about 15 coats, but I sanded through the finish on a regular basis. Now I do 20-22 thin coats and they do the job. No idea how thick they are. But they are good looking and not massive, so I guess that's ok.

Herman

What I have found with my work is if I am sanding through in places, I do not have a level surface; basically sanding through high areas trying to sand low areas. The additional coats you are using may be providing enough depth to fill the low areas. I use a zpoxy fill. I like things dead level before I apply any lacquer. I can tell this as I am able to sand back the last zpoxy application with no sand throughs and no shinny areas left.

An inexpensive and accurate way to measure how much coating you are putting down is the use of a mil card like this

http://www.concretecountertopsupply.com ... geWet.html

This will tell you what the thickness of your wet coats are. You can then figure what the final dry film build will be from the percentage of solids in your coating. You must remember to account for thinners and retarders you add to the material to make up your ready to spray mix.

I've read that some folks tape a business card to the soundhold. They measure the thickness of the card and write it on the card before hand (measured with a caliper). Then after applying the lacquer coats, they measure the thickness of the card again. Subtract the original card thickness and you have the thickness of the applied finish. Never tried it but it should work.

I use a card in the sound hole

I use tape in the sound hole.
I am no leveling one time only after about 12 coats, then spray the final coats.
This worked pretty well on the last two.

Kevin

What do you do if you sand through to the wood on nitro??

nehsgolfer wrote:What do you do if you sand through to the wood on nitro??

Apply more.