Wednesday, February 13, 2013

Why toolboxes and tool handles stink.

Tools with Cellulose Acetate Butyrate handles

For years I've encountered this issue, and it always perplexed me: why do a lot of toolboxes stink? I had always assumed it was related to heavy use with sweat and dirt and zero cleaning, but after I started encountering it on my own, barely used tools, I started looking into it. You can find some posts on DIY forums asking the same question, and how they could never clean the toolbox well enough to get rid of the stink.

Eventually I found someone who pointed out it was coming from the tool handles, and then they pointed out the culprit: tool handles made of Cellulose Acetate Butyrate. A thermoplastic, it offers excellent UV and solvent resistance that cellulose acetate doesn't offer. And it feels in the hand like a natural substance, something that is almost intangible, like a tool that is made by craftsmen, a characteristic that a polyethylene or polypropylene handle does not have. CAB also offers no splinters like the older wood handles. It also can be very clear. And when that plastic begins to degrade, it releases free acetic acid and butyric acid.

The odor of vinegar is a familiar sign to those in the film and photographic business; the cellulose acetate backing of film releases it as it degrades. I was visited a famous photographer's house and his office where he stored his negatives had that acrid odor--while for a photographer it reminds you of the darkroom, the midpoint of the creative process, it also brings to you vividly the end of the process--the decay of the work.

The butyric acid, one of the carboxylic acids, with a formula of CH3CH2CH2COOH, just smells like, in polite company like parmesan cheese, or like rancid butter or vomit. It's not nice above a certain concentration. Once I discovered this I immediately spent a little time sniffing each tool I had, and in short order discovered the ones that are the problem. They immediately got isolated from the rest, because the free butyric acid really does migrate and make everything unpleasant. I thought about giving the tools away, but really, who wants such a tool, even if free? I was going to throw them out, but that made me feel bad. And I think I've found a solution to stinky tools. I carefully fully coated the handles in two coats of shellac, a natural sealer, and now they don't smell to my nose.

4 comments:

Anonymous said...

Thank you so much for the info. We've been so puzzled by our stinky tool box. Your article is well written as well, btw. Thanks.

Anonymous said...

It took me a long time to check this out on the web, because I was certain it was something we did. I thought someone had spilled some toxic substance on the tools, or used them to mix something smelly. I had only just figured out, through the process of elimination, that it was the plastic handled screwdrivers. What in the hell!!?? We can put a man on the moon, etc. etc. Is this really necessary? Can we just get wood handles, or some other damn thing that doesn't smell, and let us get back to work without this LUNACY driving us crazy? Another ill effect of the space-age, let's get back to what we know works and won't hurt us, I don't need shiny objects, just tools that work and don't annoy.

Dean W. Armstrong said...

I am at a loss as to why this comment was removed:
Anonymous has left a new comment on your post "Why toolboxes and tool handles stink.":

So, now that we have identified the culprit, how do we neutralize the smell?

1. in the toolbox
2. on the metal tools
3. on the wooden and non-stink plastic handles
4. on the stinky plastic handles

Dean W. Armstrong said...

4. I've read that if you convert butyric acid by neutralization via sodium bicarbonate into sodium butryate it becomes non-stinking. But I've not tried it.

1, 2, 3: separation, extra cleaning, sunlight, and perhaps sodium bicarbonate. Once I removed the smelly items I cleaned the toolbox with a variety of cleaners to reduce the smell, but it really was the removal and sealing of the decomposing tool handles that stopped and started reducing the smell factor.