# Water based "lacquer" doesn't REALLY burn in, right?t?



## Quickstep (Apr 10, 2012)

I've been experimenting with a variety of waterborne "lacquers". Most if not all say they "burn in" to the previous coat, but they also reference a re-coat window. If it needs to be recoated within a certain time frame, it's not really burning in, right? Is it more like it's cross linking to a previous coat that's not quite fully cured, right? 

If I miss the re-coat window, will I risk adhesion problems?

Also, what about repairs a year down the road? 

I know some of you guys have great understanding of the chemistry involved in these products and I'd appreciate the insight.


----------



## Hammer1 (Aug 1, 2010)

No, waterborne lacquers do not burn in. It's as you said, re-coating within the window is fine. If not, you have to wait and then sand the surface. Nitrocellulose lacquer does burn in, additional coats will re-activate previous coats. The dreaded mud slide on vertical surfaces happens if a novice apples too much and they always do! Repairs on acrylic have no adhesion issues since you sand. The problem is liquid building on top of the existing finish, creating a visible layer that must be buffed down. Same with nitro or any other top coat. People worry about repair down the road. It's about as likely as getting hit by lightning. When they do call, it's because junior scribbled all over the dining table with a ballpoint. Try Mohawks pre-cat and the compatible products.


----------



## GeorgeC (Jul 30, 2008)

Never heard the term "burn in" used in this way. Please define.

George


----------



## woodnthings (Jan 24, 2009)

*burn in...*

Solvent based lacquer will melt into the previous coat. Water based has no solvents, and won't adhere without a scuff sanding.


----------



## Quickstep (Apr 10, 2012)

Thanks guys,

You comments "If not, you have to wait and then sand the surface." -and-
"won't adhere without a scuff sanding" make perfect sense. 

Here's the thing though...... I've been sanding between coats using 400 grit paper. The finish powders nicely and the resulting surface looks great, but the sanding lines, tiny as they are, telegraph through the next coat. I've avoided this by sanding to 800, but I wonder if that provides enough "tooth" for the next coat. Any thoughts?


----------



## Al B Thayer (Dec 10, 2011)

Quickstep said:


> Thanks guys,
> 
> 
> 
> ...



I wouldn't worry about "tooth". Sanding is important for getting the surface level and to remove the micro layer some finishes develop in there drying stage.

Al


----------



## GeorgeC (Jul 30, 2008)

woodnthings said:


> Solvent based lacquer will melt into the previous coat. Water based has no solvents, and won't adhere without a scuff sanding.


I am certainly familiar with what you said. Just never heard the term "burn in" used to describe that action. Seems to me the term "melt in" would be closer to what happens.

George


----------



## RandyReed (Jul 30, 2014)

Quickstep said:


> I've been experimenting with a variety of waterborne "lacquers". Most if not all say they "burn in" to the previous coat, but they also reference a re-coat window. If it needs to be recoated within a certain time frame, it's not really burning in, right? Is it more like it's cross linking to a previous coat that's not quite fully cured, right?
> 
> If I miss the re-coat window, will I risk adhesion problems?
> 
> ...


Thats correct. The time frame simply means that you can apply another coat without scuff sanding. Outside of the time frame, you would have to scuff sand before reapplying. If you dont resand after the suggested time frame, then yes, you will encounter adhesion problems in some cases.

As far as repairing, you would scuff sand, repair the area, and then apply the topcoat to the entire piece/section to ensure the same sheen throughout.


----------

