On Friday, July 31, 2015 at 5:01:04 PM UTC-4, Leon wrote:
On 7/31/2015 2:55 PM, DerbyDad03 wrote:
On Friday, July 31, 2015 at 3:22:48 PM UTC-4, dadiOH wrote:
DerbyDad03 wrote:
On Friday, July 31, 2015 at 10:28:04 AM UTC-4, John McCoy wrote:

If I'm not mistaken, polyurethanes take 100 hours or more to
completely cure. So you should be safe applying a new coat
within that time without sanding, it will chemically bond to
the coat below. Of course, it likely does vary between
varnish types and brands. As Mike says, check the
manufacture's instructions (altho those are probably
conservative).

I assume by "conservative" that you mean they probably want you
to wait longer than is actually necessary.

The problem is, the Minwax WOP says to sand it after 2-3 hours.
After 2-3 hours, in my experience, the WOP still seems to be too
wet/tacky/sticky (pick a term) to sand. 2-3 hours seems - at
least to me - to be a far cry from conservative.

You've never said whether you are using oil or water base varnish
but still sticky after 2-3 hours would indicate oil, right?

Actually, I never said I was using varnish. I am not. I am using
Minwax Wipe On Poly, but yes, it's the oil based version.

FWIW "varnish" is pretty much a generic term to describe any clear
protective finish including shellac, lacquer, etc. Basically a resin
dissolved in a liquid.



Uh oh...I suspect some interesting reactions to that statement.

While you are correct in saying that varnish is often used as a generic name for various clear finishes, I'm not sure that the wRec is the right environment to propagate the myth that all clear coatings are varnishes. You'll just confuse people like me!

We shouldn't call all photocopies "Xerox copies", we shouldn't call all personal watercraft "Jet Skis" and we shouldn't call all peanut butter and marshmallow spread sandwiches "Fluffernutters" - ahh...the memories. :-)

Since this thread is discussing - in detail - the application methods, dry time and durability of various finishes, I think it would be confusing if I responded to dadiOH by saying I was using an "oil based varnish" after I started the thread by saying I was using Wipe On Polyurethane.