Varnish Question

[K90]

I have put on three coats of varnish, two thinned 1:1 and then most recently one coat thinned three parts varnish to one part mineral spirits. When the coat is applied and wet, the whole plank from rib to rib is covered, but with each coat so far it looks like the varnish is scared of the ribs and runs away as it dries. This most recent coat looks better than the first two, but can anyone provide assistance as to why my finishing job is looking like this?

 

[JSRIII]

I would try putting the varnish on straight. My guess is that thinning is making it runny and causing your issues. Don't put it on heavy but several light coats is better.

 

[Benson Gray]

My understanding is that this behavior is not unusual during the first few coats. There are small spaces between the ribs and the planking so the capillary action causes the varnish to be drawn into these areas leaving thin spots along the edges of the ribs. It should be reduced and eventually eliminated in future coats, especially as the viscosity of the varnish goes up. Good luck,

Benson

 

[K90]

Thank you both. I'll give it another coat tomorrow morning without thinning and see what I get.

 

[Dan Miller]

Follow the instructions on the can with respect to thinning. Most varnishes need to be thinned 10% or so for final cuts. The dry areas alongside the ribs are due to the varnish being sucked under the rib, as Benson suggested. You know when you are done varnishing when this stops.