Sometimes I have issues with the quality of the finish - the finish cures well but it forms a slight hazy finish which is only visible under artificial light and when applied on black thread. It's like smudginess / milky appearance. I don't think it's a question of mixing because the finish cures very well and on many occasions I also had perfect quality even on black thread. I noticed that this problem emerges usually when temperatures get below 65 - 70 degrees. I also work in a basement where humidity is regularly between 70 and 75 % so I'm not sure what influence this is having. However I also managed to get perfect finishes in the same humidity levels. Do you believe that colder temperatures can lead to this imperfection ? Do you suggest I use heat lamps ? By the way I'm using Pro Kote medium build.

What you're experiencing is called "amine blush" and it only occurs under situations of precise combinations of moisture and CO2. This is why you can get a perfectly clear finish on one rainy day, and experience blush the next. Beyond that, and in and of itself, humidity has no effect on epoxy. It will still set and cure at the same rate and in the same way.

Amine Blush doesn't harm the finish properties and most often it'll go away if you set the rod in a very warm place for a few days. Setting it inside a sunny window will often take care of it in a few hours.

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Thanks Tom. It's strange that there is CO2 concentration as the basement is well ventilated. What about the cold temperature ? Can it lead to smudgy effect on finish, removing the shiny glossy element ?

The cold would affect how long it takes to set and cure. From about 70F, every 20F up or down will either halve or double the set and cure time. Beyond that, the cold wouldn't necessarily have anything to do with the amine blush.

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I've had a similar problem lately, and have been thinking about posting it. I'm not getting a hazy / smoky / milky appearance. I'm getting a almost an oil on water effect. It doesn't show up in the mixing cup, and doesn't show up when applied to the wraps. It appears right around the time I'm done hand turning, and ready to start the dryer. It will be there when the finish has cured, and does not go away over time.

I've been using Fuji thread, Chroma-seal CP and Flex Coat epoxy. I've had very good results, for a newbie, with this combination in the past, so this new problem has me confused.

It does not seem to be a problem with proportions. I mix by mass. I know the S.G. of the components and measure with a very accurate scale. And I don't think it's a mixing problem. The finish always cures nicely since I've been measuring by mass, and I mix it well.

It would seem to me to be a contamination problem, but I have no clue where it could have originated.

I use the 4oz bottle of finish with Yorker caps, so when dispensing I use no tools; just drip it out into the cup. I always use a fresh cup and fresh stir stick.

I have at this point thrown away the remainder of that bag of sticks and cups, as well as that batch of epoxy. So I have new cups, new sticks and new epoxy.

Still having the problem.

Any Ideas? I'm stumped.

Gary - that's the same thing. Amine blush. That's why nothing you have done thus far has eliminated it.

It will tend to go away if you keep the rod in a very warm area and occasionally wipe the surface firmly.

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Take the same formula of finish upstairs and coat it in a bedroom, spare room etc. You can work in the "cellar" for the next 50 years and your finish isn't going to work properly. You will see the difference.

What do you suggest we do to avoid this Amine Blush ? dehumidify ? heat lamps ? not sure how to eliminate CO2 further, given the place is already well ventilated ...

If you read the article from the epoxy formulator in a recent issue of the magazine, you know that it's not really something you can completely eliminate, nor is it something you can conjure up at will. Working in a damp basement in colder temps won't necessarily cause it.

Generally, by finishing at what is considered "room temperature" which is going to be somewhere between 70F and 80F, you'll get the best results. This is the temperature that most epoxies were designed to be worked at.

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Tom is correct, it is the combination of humidity and CO2, with humidity the biggest culprit! Low temperature and high humidity can cause some condensation on the wraps which makes for the surface appearance of an oily finish. The best solution is to do the finish work in an environment with temperature above 70 degrees and low humidity. Increasing the temperature alone often does not solve the problem as warm air actually holds more moisture than cold air.

Try using a hair dryer on the wraps now and see if the blush disappears.

Put a dehumidifier in the work shop to reduce the humidity.

Then, use heat in the work shop to keep the rod at 80 degrees or above when drying.

Be safe

Thanks again everybody. I have my little rod workshop in a small cabin I recently acquired. It has a small AC unit and a small gas fired ceramic heater. I run one or the other only when I'm there. The problem I'm having is a recent one, basically since it has become quite a bit cooler and damper here in the middle of Illinois.

Low temps and humidity in the cabin seems to be the problem, and an easy thing to test. I can easily make it warmer, and I have a small dehumidifier I can move out there, if it still functions, that is.

What about CO2? I've been using a piece of soft plastic tubing to blow on and pop small bubbles. Is this enough to cause the blush?

I don't like to blow on bubbles just for the reason of possible contamination.

If I have bubbles, I use my heat gun to take care of them. No issue with the heat gun use.


Be safe

Yes, it often (but not always) coincides with using human breath to pop bubbles.

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Thanks again folks. I have an IR lamp I can use to pop bubbles. I need to be a bit more diligent about not having bubbles in the first place. I'm getting better at that, but still get a few.

A light finish will for sure help -- and heat the place up

Bill - willierods.com

Thanks guys. I've equipped myself with a heat gun and a heat lamp to test things out.

Alistair,
Just remember - gentle heat!!

Too much heat causes all sort of issues.

Be safe

I'm in agreement with Roger...............be very careful with the heat gun!

Amine blush is water soluable. See if it comes off with water. Solvents won't touch it. Wet sanding and another coat is sure fire cure.

But your problem might be something else. In cooler climates it takes longer for the epoxy to cure. I'm concerned that you might be putting the finish on when it is warmer...and then it is turning cooler before the epoxy has cured enough. Try to get all the parts/items same temp, and maintain that temp, until you are cured. If you don't won't to condition the cabin for that period of time consider a drying box.

Russ in Hollywood, FL.