Tracking Down a Silicone Contamination Source

Thoughts on how to figure out where that bad stuff is coming from. June 9, 2007

I am trying to locate a problem with fisheye in our finishing line. It's very difficult to narrow down in a 100,000 sq ft factory. Does anyone have suggestions on how I can find the source?

Forum Responses
(Finishing Forum)
From contributor R:
What have you already ruled out? Lots and lots of information awaits you in the Knowledge Base. Everything from deodorant to hair tonic to corn chips can cause this problem.

From contributor G:
I'd say that you will need to pull test samples from the various work stations and do individual tests on them to see where the fisheye starts. Pay attention to potential contamination sources all around the work stations. Place large signs at all the shop entrances saying "No Silicone Allowed". It could be anything - such as somebody wearing the same clothing that they detailed their car in.

From contributor D:
You may also need to check for things outside of your building. We had a customer that installed a new, bigger air makeup unit, then all of a sudden they were having fisheye problems. After weeks of trying to find the culprit, they discovered that the Red Wing Shoe factory up the road was causing their problem. The new air makeup system was pulling in the silicone that was present in the outside air.

From contributor J:
Here is what I usually did when those damn things started to show up. First, you will need some clean glass, like window panes. Not too big, about 4x6. Next, clean them very well with lacquer thinner and clean rags. Now take a sample of the product that has fisheyes. Also take a fresh sample not in use from an unopened container. Now take them to an area other than where you are having the problems. Also, make sure you have someone other than the person that was having the problems spray out the two samples on separate glass pieces. If you still see fisheyes on both glass pieces, it is either your air or you have contaminated paint. If the unopened one doesn't, but the one that you were using does, either that batch or that container is the problem. If none fisheye, then you need to test your sealer or primer coat.

The best way to start looking for fisheyes is to go backward from topcoat. But it could then be like what others have stated.

From contributor M:
Man, that's awful, sucking in silicone from the shoe factory. I would not have guessed that.

If your company has any fish-eye killer around, it's basically concentrated silicone, so anyone goofing around with it will cause wailing and gnashing of teeth. I keep it in a fire-proof cabinet that basically only I muck around in. Second, in such a large factory, you may have a hard time finding any source of contamination. If I were the owner and didn't want to rip the place apart looking for anything containing silicone, just include a note with the paychecks that says "Search the shop and give us *every* item you find that lists "Silicone" as an ingredient for a $5 bill." That should turn up, fairly quickly, and you didn't have to do spend all day.

From contributor N:
I always start with the compressed air by putting a water and oil trap on my air inlet. The one I use has a regular filter, then a desiccant filter. You can get them at your local spray equipment store or Grainger Industrial Supply online.