# Waterbourne varnish over water base stain issue



## Alex451 (Feb 10, 2021)

Having a terrible situation here. I'm hoping someone here can help me out.

Ive never had this reaction with clear coating stain before. I'm refinishing red oak treads to stain match their grey floors. (These stairs were finished long ago and were covered with carpet for 30 years or so)

-Scraped off a layer of the old finish

-Machine Sanded with 60 grit to bare wood

-Machine Sanded with 80 grit to make sure I took out all the old finish

-Hand sanded with 100 grit in the direction of the grain

-Cleaned the surface with vacuum and wet rag

-Brushed two coats of Sansin enviro stain (one coat wasn't looking good enough, dried quickly and the wood absorbed the stain nicely)

-24 hours later I try to brush on Bona mega waterborne varnish and it reacts with the stain immediately as i brush it on. Almost like im brushing on paint stripper. It started to take off the stain right away as im brushing it... never experienced something like this before.

-I called the paint store that matched this stain for me and they even say they tested it with bona mega with no issues. They are telling me the stain might not be dry enough and I should wait another 24 hours before applying the varnish.

-Called Bona 1800 number and their "expert" let me know they don't test bona on water based stains so they cant give me any advice.



Has anyone had this happen before ? I'm really worried that the issue might be that the old varnish has somehow penetrated so deep into that wood that it sealed it so deep.


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## cocomonkeynuts (Apr 14, 2017)

sansin is some of the worst product I ever used. At this point I would suggest brusing a coat of shellac and hope that seals it without lifting the stain. Your store should take some responsibility for selling you on two different product systems...


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## Redux (Oct 27, 2018)

If you’re using the Mega One, the propylene glycol could be dissolving the binder in the stain. I’ve used a ton of Bona Traffic HD and the older aziridine crosslinked Mega, but always used dewaxed shellac over water based stains to prevent discoloration due to tannin pull and to better bind the pigments. It’s always best to sample out your materials first, especially when mixing & matching stains and clear finishes by different manufacturers.


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## Alex451 (Feb 10, 2021)

I might have to try the dewaxed shellac later.

I made another sample with a different varnish product ( Behr water based poly) to see if it would make a difference and it reacted identically. Going to try again in 24 hours and see if that changes anything.


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## Redux (Oct 27, 2018)

Alex451 said:


> I might have to try the dewaxed shellac later.
> 
> I made another sample with a different varnish product ( Behr water based poly) to see if it would make a difference and it reacted identically. Going to try again in 24 hours and see if that changes anything.


A lot of times the pigments in waterborne stains are very loosely bound with just a splash of acrylic resin and sometimes pull when clear coated if applying more than one coat of stain. Hopefully the dewaxed shellac works for ya..


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## finishesbykevyn (Apr 14, 2010)

I've found that the water based stains are easily "re-wetted". Not so much an issue if your spraying on the clear coat, but using a brush can easily re-wet the stain. @Redux I would have figured the alcohol in shellac would have the same effect on water-based stains? But apparently not?


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## cocomonkeynuts (Apr 14, 2017)

Redux said:


> A lot of times the pigments in waterborne stains are very loosely bound with just a splash of acrylic resin and sometimes pull when clear coated if applying more than one coat of stain. Hopefully the dewaxed shellac works for ya..


the sansin is essentially pigmented water if you ever have the displeasure of having to use it. must be a canadian thing because the saman stains are similar in that its basically pigment suspended in glycol and water. easily rewetted even 48 hours later


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## Redux (Oct 27, 2018)

finishesbykevyn said:


> I've found that the water based stains are easily "re-wetted". Not so much an issue if your spraying on the clear coat, but using a brush can easily re-wet the stain. @Redux I would have figured the alcohol in shellac would have the same effect on water-based stains? But apparently not?


Shellac works well over many water based stains as long as they’re not high build sealer type stains with a high resin content. Most of the pigments & dyes used in water based stains aren’t alcohol soluble, so as long as they’ve penetrated the wood, even if agitated by applying shellac with a brush, the pigments won’t be disturbed. I’ve always tested, re-tested, and tested again before putting something like that into production, also testing for adhesion as well, particularly when used on floors or stair treads.


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## Alex451 (Feb 10, 2021)

This job taught me that I was too overconfident with applying stains. I don't do them often enough and really should be doing samples before putting it on the clients woodwork. 

I wiz rolled the first coat of varnish which didn't disturb the stain nearly as much as brushing it to seal it. Next day lightly sanded with 220.

For the second coat I mixed in 1-3 stain to varnish and brushed that on which fixed all the red oak reveals and made the entire stain job look very consistent. In hindsight I should have done this step from the get go and brushed a clear coat on top.


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