I'm thinking about mixing up some Ol Workhorse this time around and was curious about shelf-life when compared to Old Reliable. I should know this, but there have been so many formula references floating around lately, I have them mixed up.

I haven't been shooting as much lately, but aside from cutting back and making smaller batches of collodion, I'd like something that'll last awhile as well.

Thanks!

Andy

Don't forget that Coffer says you can refrigerate OWH to stabilize it long-term. Of course, you'll want to seal it up to contain the vapors.

I always refrigerate my 'mother' batch. While it presumably extends the lifespan somewhat, I really don't know how to gauge just how much of an effect it has. But it can't hurt. Just seal it well and mark it as poison, and tuck way in the back!

I remember hearing OWH is 6 months and OR 1 year.

Take care too that youre using something beside a cork for long term storage, quality screw top bottles or glass stopper.

I only use Pyrex 1394 screw-top bottles to store my collodion, so no issue there...

So is it safe to say OWH will keep longer than Old Reliable?

shelf life, as long as you take vapor loss out of the equation, is a factor of increasing acidity which breaks down the cell walls of the nitrocellulose. When you use iodides and bromides which do not change fast into an acid state, the collodion lasts longer. Eliminate all potassium compound from your collodion and it will have a longer shelf life.

Gotcha.

i have the same situation. i have not been shooting as much. i dont want to waste collodion. so i think next time i will make half a batch.