Decanting Stain into "what kind of containers"?

G'day folks,
New to the site and frankly working with wood in general.
Recently I attempted to decant the remaining contents of Miniwax Polyshades as the original tin has lost its integrity due to my use of a hammer to secure the lid.
The only container I had on hand was an empty tin (clean) of Nescafe.
However, when I went to use the stain again, it had formed a "skin" (rather thick) something that had never occurred in its original tin.

Why did this happen?

Furthermore I recently purchased a lot of "prethined"? (for spray application) wood stain from Auction. These are stored in 20ltr tins and I'd like to decant them into smaller containers, for use and resale. What is an appropriate container to do so?

Thanking you all in advance.

Regards,
Adam

Hi Amra, Welcome to the forums. My knowledge does not extend to the Miniwax products, nor to spray materials. Well, you might ask, what the hell are you doing answering me then? However, the answer to that is 1. to greet you - these are good, friendly forums so you need to know that, 2. From first (materials science) principles you may need to know that not all containers are created equal. Some containers allow air/oxygen to go through - that is a disaster for most stored materials. It may seem strange that some containers are so much more expensive (and sometimes that is just a ripoff) but sometimes it is because it prevents air/oxygen/moisture getting to the product.

How much free space did you leave in the tin, if you leave a large amount of free space it will start to go off, just as if if it were out the open

Welcome to the forum Adam.

I had a bottle of boiled linseed oil that had the lid crack, one of those things that happen when if falls off the shelf. :doh: What I had on hand was a water bottle with the pull up/push down cap. I moved the remaining liquid to this container and it has held up ok. It has been about two years now that this has happen and the cap has dried in place twice. Just a matter of cleaning and working it free so not really bothered too much.

I think your Nescafe tin might not be completely air tight so the tin was breathing and the finish was curing. Even with half finished paint tins I normally turn them upside down. One drawback to this is that if the lid is not seal properly the paint will find it's way out. If in a garage just adds to the patina for the garage floor. :U

A good solution for water based finishes is to decant them into a washed out wine cask. You massage it by hand to mix it when you need it.

Keeps the air out and is great for dispencing small quantities as well.

Don't know how it would work with non water based finishes but it might be worth a try.