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Adhesion problem Kem Aqua Plus10/24
So I am having some adhesion issues on some stain samples and wondering if anyone has some suggestion as my rep is having difficulties coming up with a solution. The issue is the Kem Aqua Plus sealer is not adhering to the Sherwood BAC wiping stain which I'm told it should do.
Wood is maple veneered and solid
sample 1 (left in picture)
Sample 2 (right in picture)
Both samples left to dry for 3hrs to allow solvent to evaporate
Seal Coat both samples
35 mins dry time
2 top coats Kem Aqua plus dull rub
I can us my finger nail to easily scrape the finish down to the stain without issue and on sample 2 you can see the tape lifted the sealer as well.
It been 72hrs and I can still remove the finish with my finger nail. I have used this same process with the Mohawk line of solvent stains and WB pre-cat lacquer (as they call it) with no issues. Great adhesion you can only mar the surface if you drag a screw driver across and that is what I was expecting to see with the Kem Aqua Plus Line
I would like to keep it as much of a WB process as possible (I understand the wiping stain is not) and don't want to have to resort to a shellac between the stain and top coat.
Any thoughts on what the issue may be?
Whats the pigment load in the stain? How clean are you wiping it off?
Mohawk stains dry pretty fast, probably why no issues there.Use waterbased stain. Likely no need to pre dye and you will be able to recoat way quicker than 72 hours
You said you used Seal Coat after allowing the BAC to dry for 3 hours. Seal Coat is shellac, so I'm confused why you later said you don't want to use shellac between the stain and KA+. You already are, and there's nothing wrong with that. I've used that same process many times w/o problems, though with a different WB topcoat. However, I think you need to let the BAC dry a lot longer than 3 hours, more like at least 8 hours, and also let the Seal Coat dry for at least 4 hours before applying the KA+.
You can usually apply WB topcoats over most oil and solvent based stains w/o bonding problems as long as you allow them to completely dry. For some OB stains that can mean 3 or 4 days.
John is correct in his approx dry times.
We have used MLC Woodsong solvent stains for a long long time. Our dry times would typically be overnight for the solvent stain. If we had to use an oil based Minwax type stain. We would allow it to dry overnight then barrier coat it with Sealcoat shellac. Wait until the end of the day(4-6hrs) then topcoat with a web.
The wb stains are so good these days, that you should’ve able to find one that suits your requirements.
A good rule of thumb for using somewhat incompatible products(oil/wb/solvent) together is the smell test. If you can smell solvent then it’s still off gassing, which will affect bonding.
I have done up some more samples and I will let these sit over night as suggested to see if that solves my problem. Thank you for the replies!
A second question that comes to mind is what is the grain raise like on waterbased stains and how do you prep from that?
How old is the Seal Coat? Shellac will dry slower the older it gets. Finally gets to the point where it has to be thrown away.
3hrs is not enough drying time to go from a solvent stain to a wb sealer or topcoat. Start of the day, end of the day. Not before lunchtime. 6hrs should be adequate.