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Prep Work - Mr Eddie - 05-02-2016

I've been reading up on finishing techniques and learning a lot from the posters on Woodnet. My question is - How do you prep, after sanding, before brushing or spraying a finish? Blow off the dust and wipe down with mineral spirits? Previously, I used a tack cloth on a little table I made and had mixed results, mostly user error. I am finishing a work table for my shop and going to brush on EnduroVar. The top is maple plywood and the sides are trimmed in soft maple. If you can recommend a finish that you think will work better I'm all ears. As always, thanks for the help.

Lonnie


Re: Prep Work - JR1 - 05-02-2016

Assuming no problems I go right from the hand plane to a couple coats of shellac. I like the way it brings out the grain. If I need to adjust the Color I just add some transtint. If I have some problems, tearout, then I use a 80/120/180 grit progression. If it's not going to be hard use then 2-3 coats of shellac is fine. I topcoat with GF or Crystalac waterborne for hard use. I use the shellac to bring out the grain as wateborne dimmenishes it.


Re: Prep Work - Restorer - 05-02-2016

I always wipe down with mineral spirits. Why would you blow dust off and get all that crap up in the air? I wear vinyl gloves or rubber or latex whatever you prefer or have. Once I get to the wipe down with mineral spirits I never touch the piece with bare hands again. I do the between coat sanding with gloves and the following wipe down with mineral spirits. I am not a fan of General finishes I think about anything else is better. I also do not use tack cloths, I used to many yrs. ago and they created more trouble with fish eyes than any dust they removed. I know many here like them but it seems you have to be selective about the brand. I've found mineral spirits, lacquer thinner, paint thinner whatever you keep on hand work better to prep the piece for finish. Now you are not trying to drown the piece in fluid, slightly more than damp works best for me. Then set it aside for 15 to 20 mins or till dry.


Re: Prep Work - Mr Eddie - 05-03-2016

JR1,
My take from reading the forum is that shellac is a good all-around base coat for sealing and helping to bring out grain. Do you generally, always use it as long as it's compatible with the top coat? I have some Zinsser Bulls Eye that I'm going to do some samples of to start getting experience. I'll try some flakes once I get further along.

Lonnie


Re: Prep Work - Mr Eddie - 05-03-2016

Restorer,
You are correct. I made the mistake of removing my gloves to feel the top of the small table I referenced earlier. Between that and using the tack cloth incorrectly I got a good case of 'fish eyes'.

Lonnie


Re: Prep Work - Cooler - 05-03-2016

JR1 said:


Assuming no problems I go right from the hand plane to a couple coats of shellac. I like the way it brings out the grain. If I need to adjust the Color I just add some transtint. If I have some problems, tearout, then I use a 80/120/180 grit progression. If it's not going to be hard use then 2-3 coats of shellac is fine. I topcoat with GF or Crystalac waterborne for hard use. I use the shellac to bring out the grain as wateborne dimmenishes it.




I have always put down shellac as a base coat under poly. However I read recently that poly bonds better directly to the wood. Now I don't know what I will do for my next project.


Re: Prep Work - JR1 - 05-03-2016

The only thing that I know of that has problems over shellac is NC lacquer and that only over waxy. Oddly shellac works fine over NC lacquer. I agree with don't blow dust and other toxic finish spoilers about. I use a vacuum cleaner an then MS or alcohol (depends on the finish and the wood [alcohol works better on ipe]).


Re: Prep Work - JR1 - 05-03-2016

In almost all cases the shellac brings out the grain and adjusts the color. I very rarely use as a sealer for waterborne finishes of any species unless there is a stain or dye to protect .


Re: Prep Work - Demps - 05-04-2016

Cooler, to your point..I am currently refinishing a kitchen table top (chem strip old lacquer, well sanded) and planned to go sealcoat, then GF enduroVar. I called GF tech service to confirm my sanding and application schedule. The tech said "no shellac" with this product. It self seals and works best with itself. The data sheets on GF website indicate same. Additionally 320 grit between coats, nothing finer.


Re: Prep Work - Cooler - 05-04-2016

Demps said:


Cooler, to your point..I am currently refinishing a kitchen table top (chem strip old lacquer, well sanded) and planned to go sealcoat, then GF enduroVar. I called GF tech service to confirm my sanding and application schedule. The tech said "no shellac" with this product. It self seals and works best with itself. The data sheets on GF website indicate same. Additionally 320 grit between coats, nothing finer.




I will probably do an adhesion test just to be sure. The standard test is to use a sharp blade and score the surface into a 1/4" x 1/4" grid. Then they apply a laboratory grade tape (3M 250) and then they peel off the tape and see if the finish lifts with it.

I will try it over shellac and directly over wood. I will try it with blue tape, masking tape and packing tape and see if I find a difference.

I've never had any peeling of finish but why waste the time putting down shellac if it is not accomplishing anything?