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vinyl sealer adhesion1/25
I have adhesion issue using vinyl sealer.
The wood is bare ash( no refinishing) I sand it to no more than 120 grit since at 150 I get seem to have issues.
1rst question concerns first the wood. I have seen various people recommanding to sand no more than 120. I have also tried raising the grain with before the washcoat to get more grip before the washcoat.
2nd concerns toner should i scuff that coat.and is it ok to make it with viny since my CV dont like thinning
3rd I have been able to get good results so far but always end up with a more fragile finish when staining than barewood selfseal. is it normal(the result is still pretty hard though)
That oil stain can be a problem if it's not
Regarding the stain it is supposed to be able to be topcoated after 1 hour (mohawk) although i prefer to wait until I cant smell the mineral spirit/paint thinner sent.
when it is dry do you scuff sand the stain?
regarding vinyl sealer the pds sheet state no build limits other than the total system but I suspect that building it too much is the problem because to rule out stain I applied cv directly over the stain after like 30 min when it still smelled oil and no failure.
I used to Dye-washcoat-stain-vinyl seal-vinyl toner-vinyl seal and by the last vinyl seal coat it became very fragile. Or if it seems good as soon as the first coat of cv gets sprayed the finish gets brittle
Even if the manufacturer give no limit when reading similar products from other brands most state a 0.5 to 1mil MAX thickness.
so regarding the vinyl am I right trying to apply as less as possible.
If I try the following schedule :
normaly here I applied a full solid coat of vinyl but it always ended up fragile. should I just go with CV after the toners. this woild result in just 2 coats of vinyl sealer 3% wich would result in a minimal build
Your schedule sounds complicated!
I know thats why I am trying to simplify it as much as possible. I will try to put thw toner color directly into the topcoat wich will eliminate a step and thus reduce overall build
*although my ash doesnt really blotch this step help bind the dye because if I apply the stain and wipe it directly over the dye I end up removing some of the dye.
the 3 color steps is the only way I get statisfying results because neither alone seems to do it
Are you catalyzing the vinyl ? And, why the dye over the oil ?
the wood is dyed FIRST
the vinyl is not catalyzed since the manufacturer told me strictly to not catalyse the vinyl even with catalysed finishes. They manufacture no catalysis for it and trying to catalyse it with any product would be detrimental.
I am now trying different grits when sanding the vinyl sealers because sanding it with 220 as they recommand might not be coarse enough. I will try 150-180-220 on a test board
Unless you are experiencing blotchy staining why are you applying a vinyl coat between the dye and the stain. Unless they are the same resin base the stain shouldn't move the dye around (melt it).
So it should be dye, stain, vinyl sealer no thinning (catalyzed if using a catalyzed topcoat) scuff, topcoat, scuff, topcoat done.
thanks for your answer leo
I am currently testing your schedule but wil change the EZ vinyl sealer for a conversion sealer( both mohawk).
maybe the problem is there. I have asked the question to 2 diff. person at mohawk ( 2 phone 1 email) and they all confirmed that this vinyl sealer MUST NOT be catalysed even under precat/postcat/CV. No catalysis exist for their vinyl sealer.
anyways this vinyl sealer as always been problemating since it always ended up brittle and easy to scratch/flake whether I sprayed it wet/dry/unthinned/thinned. Somehow sometime I was able to endup with a hard vinyl coat.
anyway as stated I will be receiving mohawk conversion sealer and will try it. It will then be a catalyzed sealer topcoated with catalysed topcoat. So my routine will be:
I will probably put mohawk reducer retarder 5% in sealer/topcoat since my ash seems to bubble a lot.
You may be applying the stain too heavily. This is the only thing I've encountered in my finishing life (since 2004) that predictably can cause adhesion issues.
I suggest you skip the vinyl sealer altogether and just use a good stain and conversion varnish.
If the stain isn't coming out dark enough, wipe the surface of your product with a wet rag just enough to raise the grain (make it fuzzy). Let the water dry off and then stain your product. The stain will end up MUCH darker and much less blotchy.
Don't use an oil stain for this. Use a common industrial alkyd resin stain.
Let the stain dry for a good 2 hours and follow it with 3 full coats of conversion varnish. No sanding sealer, no vinyl sealer needed.
Scuff sanding the first coat of conversion varnish will be a bit tedious if you used water to raise the grain but the second coat will sand as flat as glass if you have good sandpaper.
As long as you're using a good quality conversion varnish, self-sealing is usually going to adhere better.
I have solved my problem. at least partially.
I have ordered mohawk conversion sealer. I have tried 2 schedule :
now regarding resistance the first one seem to have an edge over the second but the second one yield better results.
I think I was applying too thick of a wet coat. I bough a glass piece and mesured my wet coat on it since it doesnt absord the liquid.
I ended up spraying almost 3 4 semi-dry pass to get a good wet coat and avoid spraying too thick