Spraying Epifanes

General Discussion
1

Has anyone had any luck spraying Epifanes varnish? I’ve been using an HVLP to spray both the high gloss and rubbed effect varnish and am getting “orange peel”.

– Geoff

2

When you figure it out I’d love to add it to my bag of tricks. When everything is right it makes a great finish.

George

3

The air has to be totally dry. If there’s no drier on the compressor downstream of the tank, that’s likely your problem.

Compressor oil can also play heck with the finish.

I have a friend who has had great luck using an airbrush setup…less overspray, great control, easy to lay on proper coats…tiny oil-less compressor…less equipment to clean up.

You can buy the whole setup for not-much at Harbor Freight (not spam here, I own no interest, and a lot of their stuff is cheaply made junk, but it’s a good place to buy light-use tools that you might not otherwise lay out the bucks for).

4

This is an HVLP and there are no compressor tanks. It has a 4 stage turbine and runs at 6-8 PSI.

– Geoff

5

Wet air in…wet air out

And maybe the atomization process is driving off too many of the volatiles in the varnish

And maybe the atomization is foaming the varnish…the same thing can happen with brushed varnish if you shake it instead of stirring

6

Considering that I’m spraying this in New England in February, I don’t think that wet air is the issue. Freedom used to spray Epifanes and the finish was wonderful. I suspect that my major issue is viscosity, but I was hoping to find someone who has done this and come up with a “factory finish” result.

– Geoff

7

Sometimes you can get “orange peel” effect from too thick coatings; water in the air supply is more likely to leave randomly spread ‘holes’ in the finish. We had that problem when the boat was spray painted last year, and it all had to be re-done. Try moving the spray gun faster to get a thinner coating, or using a lower flow rate from the turbine. Viscosity is critical, so it would be worth actually measuring it, and adjusting any thinners used.


Good luck.

8

I am thinning it with Epifanes thinner for spraying. I just suspect that I have to thin it a lot more than I have been.

Based upon some info that I just found, using a viscosity DIN cup with a 4 mm hole, it should take 20-24 seconds to drain. It appears that they’re suggesting a 15-20% thinning.

Now, my HVLP suggests that using the viscosity cup provided, which is equivalent to Zahn #2 (which is a 2 mm hole???), it should take 18-24 seconds for the cup to drain to obtain a usable viscosity.

On Wikipedia, I found the following formulas for viscosity:

  • Zahn Cup #2: ν = 3.5(t - 14)
  • Zahn Cup #4: ν = 14.8(t - 5)

Using an average of 22 seconds for the 4 mm hole, that places the viscosity at 251.6.

Using an average of 21 seconds to achieve the recommended viscosity for the HVLP sprayer, that would place the viscosity at 24.5.

That’s basically a factor of 10 apart! I don’t know if viscosity is linear or logarithmic, but clearly they’re a long way apart, and I don’t understand the differences.

Any help in understanding this would be appreciated.

– Geoff

9

Geoff

Maybe this (and the associated links) will help

http://www.flexoexchange.com/gorilla/centistokes-not-seconds.html


Where are you spraying this in New England in February? Obviously, the temperature of the product and the surface being sprayed are critical here. Have you moved your boat indoors?

10

I talked to the “experts” at Apollo (who makes the HVLP sprayer) and they suggested that I go to a 2 mm tip and a different air cap (which directs the air at the liquid exiting the tip). They also suggested that I thin the Epafanes until I got 45 seconds thru their viscosity cup. The parts are on order from CA, so I’ll let you know once I get them and try them.

– Geoff

11

I’m happy to report that after making a series of changes, that I’m getting excellent results. Based upon feedback from this forum and others, I did the following:

  1. Three+ coats of Epifanes Gloss thinned 50/30/30% with spraying thinner.
  2. Thinned the Epifanes Rubbed Effect 25% with spraying thinner. The viscosity was measured at 25 seconds in a Zahn #2 cup.
  3. Increased the diameter of the nozzle from 1mm to 2 mm
  4. Replaced the aircap on the gun with the larger one to match the nozzle.
  5. Increased the room temp to 70F
  6. Sand with 220 or 320 between coats

Note that I’m using a 4 stage Apollo 1025 HVLP turbine and a 5000 series gun.

The final result looked just like the factory. I’m a happy man!

Thanks for all of the suggestions.

– Geoff

12

Excellent!

Can you post a few pictures?

George

13

I’ll do so when I return from skiing on Thursday/Friday.

14

I had said that I would post pictures of the final version of my refinishing with the Apollo HVLP sprayer, and I’ve finally gotten around to doing it. It’s quite hard to show the end result as the finish is “Rubbed Effect” which is a mat finish. Anyhow, here are 3 photos of a piece of molding showing a completely flat finish with no orange peel effect.

15

That looks awesome!

George

16

I am about to spray the finishing layer of Epifanes High Gloss on the deck of my boat in Thailand. It is very humit and the temperature is about 30 degrees/ 100F. I am wondering how much Thinner I should add to get the best results.

17

I am about to spray the finishing layer of Epifanes High Gloss on the deck of my boat in Thailand. It is very humit and the temperature is about 30 degrees/ 100F. I am wondering how much Thinner I should add to get the best results.

I have no idea given that temp. I thinned my final coats about 25% and used a 2 mm tip. I’d try spraying a test board that had already been coated as a test before going after the entire deck.

– Geoff