Varnish

[Canotrouge]

I’ve never tried those, but I have taken to displacing the air with propane gas from my shop torch. That seems to help, and the half used cans haven’t spontaneously exploded so far. I think it also helps to decant a sufficient amount of varnish for the job at hand and the immediately close the lid, so the can isn’t open and exposed for a half hour while I work.

I don’t know why open cans of Helmsman last better, but I squirt a little propane in those cans as well.

Look like Mike does it!!

 

[Alan Gage]

Just curious if you used a Non-Blush resin ? Jim

No, just the regular Raka "slow"

Alan

 

[Guest]

Bloxygen. That’s it.

http://www.amazon.com/Bloxygen-Grams-Finish-Preserver-Spray/dp/B001OW80PK

For $12 a can plus shipping I’ll just keep gassing propane into the cans with the lid slightly ajar.

I expect there is a cheaper commercially available heavier-than-air gas that would be most appropriate for varnish (paint, urethane). What is the gas in those computer duster cans?

Maybe nitrous oxide. Could be fun in the shop anyway.

 

[Jim Dodd]

Alan, that may be why the varnish took so long to cure. I used to have the same trouble until I switched to Non-Blush ! You would think sanding would remove the blush, I used vinegar, to clean, ammonia, and I still had trouble getting spar varnish to dry. And usually it would peel in time.

Sorry for missing Mikes propane tip ! It must work !

Jim

 

[Guest]

Alan, that may be why the varnish took so long to cure. I used to have the same trouble until I switched to Non-Blush ! You would think sanding would remove the blush, I used vinegar, to clean, ammonia, and I still had trouble getting spar varnish to dry. And usually it would peel in time.

If I am topcoating over epoxy with anything I wash it, wet sand it and wash it again.

I can sometimes feel that greasy amine blush on an epoxy coat, but washing/wet sanding/rewashing seems to eliminate any trace.

 

[Jim Dodd]

I should clarify That it's the Hardener that causes the blush, not the resin, at least with RAKA.

Jim

 

[Mihun09]

I look at it this way... if you built/restored a car, would you seek out the cheapest motor oil you could find?

 

[Momentum]

So, a little update on this topic...

As I posted in my Hiawatha build, after doing much research, I chose Interlux Compass Clear Polyurethane Varnish. Now, because I have not used this particular varnish before, I really had to go with reading about others experiences with this product.

Like many comments, this varnish is not difficult to apply, and has very good leveling characteristics. I applied it using a thin foam roller, and then followed it up by tipping it off to rid the surface of bubbles. As all have stated, you must keep a leading wet edge otherwise you will have an issue transitioning from one section to another. I will say though, that this is a very slow drying product, so don't leave yourself short of time to get your coats done. You'll be sorry you did. I have applied 3 coats of 4, so far, and it has taken on average 2 full days before I can touch the surface without leaving a finger print, and another day before I can sand it for the next coat. Too long to wait for many people out there. Could be humidity affecting curing time.

I am sanding with 320 grit between coats, with the last coat getting a 600 grit wet sand to knock down the sheen a little, as I am not a huge fan of something as glossy as I see here. You could probably get away with not sanding between 1st and 2nd coat, but I didn't. Too obsessive I guess.

I'd like to tell you how durable the finish is out in the real world, but I haven't had it in the water yet, nor have I run across any gravel. Time will tell on that, but for now, it seems to be the correct choice for me. I of course will post all about the finish once it has been "tested" so you can also make an informed choice for your needs.

Here's a couple of close-ups that will hopefully help show the finish depth and sheen.





Hope this has been helpful

Momentum

 

[Guest]

Could be humidity affecting curing time.

Someone mentioned humidity in another thread. I live in an area where high (often extremely high) humidity rules the summer months.For a variety of reasons we do not air condition our home. We have AC in cars that we have never turned on. We don’t do AC.

Except for my shop.

Even the smallest, most economical window AC unit will drop the humidity in the shop to levels better suited for epoxy, varnish or urethane cures.

I keep a hygrometer in the shop (as well as a recordable high-low thermometer). If I can get the humidity level down below 70 percent most stuff will set up nicely overnight. That often means nothing more than running the AC for a couple of hours to suck the moisture out of the air.

If the choice is that or wait several days for something to set up I’m all for the modern wonders of air conditioning.