Obviously, the safest way to remove a hickey from an offset printing press is to shut down, scrape it off the plate, and start up again. Some offset presses have the luxury of having an "automatic hickey picker". However if you are like most pressmen, you do not have that luxury. And no press operator is keen on the idea of shutting down the press and wasting paper on a new start up for every single hickey that decides to stick to the plate or blanket.
Enter the hickey picker. There are a lot of varieties out there. Most consist of a simple plastic design and will not damage the plate if scraping on the run. By the way, just for the record, I do not endorse removing hickies while the press is running. Truth be said though, most pressmen do it.
I would be interested in knowing any lawsuits resulting from this procedure. Here are a few that I know of in the offset printing industry.
Here's the way I have done it in the past.
1. Determine where the hickey is - blanket or plate.
2. Roll up a piece of 10 point paper or find a piece of plastic.
3. If the hickey is on the plate (use a strobe light to find it if you have one), scrape that spot on the plate.
4. Check a copy and hope for the best that it was removed.
This can be a real game of whack-a-mole if you have a bad ink or paper that is relentlessly causing hickeys. You would be best to troubleshoot the source of the problem and perhaps try switching out some of your raw materials.
By the way, this is the part of the job I hate the most. Even though our press is well guarded, I simply do not like to be touching anything that is touching a moving part. If you've done this, you know what I'm talking about.
I have had one incident. I used a plastic hickey picker about 5 inches long. The plate gap caught the picker and sucked it into the unit (thankfully my hand didn't). Fortunately the scraper wasn't that thick so it didn't do a lot of damage. However it ruined the blankets and gave me quite a scare. Like I said, I don't like it.
Feel free to share any interesting experiences you've had like in the comments, I would love to hear it.
Web Press Troubleshooting Guide
How To Troubleshoot Hickeys on Your Press
Heidelberg Hickey Pickers