Does Hut Crystal Finish go bad?

[Casper]

As the subject asks ... does Hut Crystal Coat go bad? I purchased a bottle and didn't notice it had a date on the back, which is outdated. How long does/can this stuff last? `Casper

[Doug Miller]

I don't know an upper limit... but I've had successful results from a couple of different bottles that were more than two years past the "expiration" date. I'm sure it varies with storage conditions, too: my shop is in my basement, so the temperature in the shop is pretty consistent year-round. No doubt the shelf life will be reduced by temperature extremes in either direction.

[Leon]

Yes It will go bad.

It is a shellac based product and shellac starts degrading the moment you expose it to air. The alcohol in it will absorb moisture from the air and eventually becomes unusable from the stand point that it may never cure.

[Doug Miller]

Remember, though, that the design of the container minimizes air exposure. As I noted in my response to Casper, I've achieved successful results with bottles that were as far as two years past their expiration date -- so while I'm sure that you're right that it will eventually go bad, in my experience that may take a while.

The best advice I can offer is to test it on a piece of scrap -- regardless of the date, if it works, then it's still usable; if it doesn't, then it's gone bad.

[-MIKE-]

Correct. There is only so much moisture in the air and only so much air in the bottle. I'm guessing, if you used it once or twice and left the

3/4 full bottle on the shelf (like me) for two years, it would be virtually new.

Like you said, test it.

[Doug Miller]

This discussion got me curious. I just went down to the shop and checked my bottle. It's about 2/3 full, and the label says "Best if used by May 31 2006".

I last used it in early October 2008, and it cured just fine. No problems.

Storage conditions play a large role, I'm sure: my shop is in the basement, so the temperature doesn't vary too much from 70 degrees all year long, and there's very little sunlight exposure. And I run dehumidifiers in the basement year-round, so that part of the environment is also well-controlled.

[Leon]

It all depends on the climate. A local Woodcraft had a bottle that was used for pen classes and it lasted about 6 months.

[Casper]

This is a still sealed bottle dated to use before Jun 30 2005. I have not opened it. I received it as part of an xmas gift. I'm guessing this was sitting towards the back of the shelf and went unnoticed. I'm torn between using it and seeing if they will take it back this late. `Casper

[Doug Miller]

If it's never been opened, and has been stored at room temperature the whole time, it's probably still good, based on my experience with the stuff. But test it on scrap first, before applying it to a project.

And forget about asking the retailer to take it back, unless you have a sales receipt showing it was sold after the expiration date. That's not right.

[Leon]

Open it and it is yours. If it were me, I'd take it back and exchange it, your receipt will help prove the point. While the expiration date does not mean that it will go bad after that, the manufacturer will not recommend using it past that date even though because of different climates it could go bad sooner than later. Even at the factory before the bottle was filled the product was exposed to air.

[Leon]

It is pretty easy to tell when other type finishes go bad, they usually dry up and get hard, shellac is different, you have to actually try it out to see if it has gone bad or absorbed too much moisture to cure properly. Typically it should be pretty dry an hour or so after application. The Hut Crystal finish I used was from a store that had only been open 7 months and the finish was still very sticky several days after being applied, I had to remove the finish with acetone.

[Casper]

That's what I'm afraid will happen. I just turned a really nice piece of pearwood and only want to bring out the grain and lightly protect. It was the only piece I had this size and the last thing I want is to have to try and strip it and start over.

My alternate thinking on this piece is Tung Oil and wax but I've never used Tung before and am not sure how it will bring out the grain.

`Casper