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View Full Version : Finishing Dilema HELP!!!!



Cornelius Dufresne
02-07-2016, 4:11 PM
Hello;

Good day Member;

Since you have a lot of finishing experience,I am wondering if you could assist me with a problem I am having.

I have a reception desk which was originally finished with lacquer since it was made in a kitchen cabinet company. I would assume in a production environment it would be nitro cellulose. I applied some lacquer thinner and the finish seems to melt.The sheen is somewhere between a flat and matte finish. I would like to refinish the unit because it has scratches and some alligatoring crazing in the finish on the top work surface. My plan would be to refinish the top and spot fix and scratches elsewhere and leave the remaining finish as it is good.I would like to stay with the Flat, matte sheen.

Here is the problem I am having. I thought I would sand the surface to rough up the finish and take out the scratches and crazing.

Option #1 My initial thought would be to use Nitro cel lacquer via a turbine HVLP sprayer. I have read and been told not to do this indoors or without proper, respirator, filter ventilation and fans as spray and fumes will go all over. I dont know if this includes turbine HVLP which has very low over spray.

Option #2 So I thought perhaps I could use a brushing laquer, but I can't find any that come in flatt or matte. Best I can find is stain which I dont think will match the rest of the desk. Not sure if I could knock down the finish with steel wool, or sandpaper to take out some of the gloss from satin?

Option #3 Then I thought perhaps I could spray waterbourne lacquer ( Target Coating entech EM 6000, or similar, since it is not as toxic as NC lacquer, but it won't melt into the original nitro cell finish so the first coat would be dependant on mechanical adhesion, in which case I could use other finishes such as waterbourne poly ( varathane soft touch matte ) or others.Only problem with polys are they are not easy to repair as lacqueropen to other possibilities or suggestion.

Your assistance is appreciated
Regards;
CD


Jim Becker
02-07-2016, 5:55 PM
You are correct that spraying solvent-based lacquer requires great care to protect against heath issues and other dangers. It's not a good idea to use it in the home or where proper, explosion proof ventilation is available. There are a lot of folks who do anyway, but I'm not one of them. I prefer to spray the water borne products and I generally use the EM6000 you speak about. Yes, it will not burn into the existing lacquer because it's not actually "lacquer"...rather, it's an acrylic product that's been formulated such that subsequent coats will chemically integrate with previous coats of the same product. No matter what product you use other than solvent-based lacquer, you'll need to take steps to insure mechanical adhesion...and even with lacquer, you'd likely prepare the surface the same way to insure things will be smooth afterward.

John TenEyck
02-08-2016, 12:54 PM
I would chemically strip the top; much easier than sanding and less risk of damage. Just tape off around the edges and work carefully and you'll have it stripped in 30 minutes. After you neutralize it and let it dry you can lightly sand it and be ready to apply your new finish. If you need to dye or stain the top, stripping it is the best process to get the old finish out of the pores so that the new stain will take properly.

Once the finish is removed you can dye or stain it, if needed. Whether or not you dye/stain it, I apply a coat of dewaxed shellac like Sealcoat, to assure a good bond, before applying the topcoats.

John