I've been using the same brand of head cleaner for a decade. Nice alcohol-based stuff. But I ran low and found that MDI PrecisionMotorWorks was able to reintroduce their "right stuff" cleaner. (The previous formula contained ozone-depleting substances, and it took years to come up with a version that performed at the level users had come to expect.) It's also worth noting that Head, Red & Roll Cleaner is in use at the Library of Congress. "Safer" and "better" is a pretty good combination.
I purchased a 4 oz bottle and put it to work. I'm in the middle of a 50-reel tape-transfer project, so I'm cleaning frequently. I thoroughly scrubbed my ATR-104's heads with my previous cleaner. When the swabs came up white, I figured I was done. But for kicks, I tried the MDI cleaner and was very surprised to pull off another swab covered in dark brown gunk. Needless to say, I was impressed. The ATR sounded great, making me wonder how this cleaner would work on other decks.
Moving on to the 2'' machine, the analogy I would have to use involves one of those industrial carpet cleaners. You know, the ones you rent from the home-improvement stores. You put in clean water, and the filth stew that you suck out of your carpet will roll your stomach. Same thing with the MDI cleaner on our 2'' MCI machine - swab after swab came out saturated in brown and black. I don't know if that head stack has been that clean since we purchased it. Sometimes it's the little things, but I'm pretty excited about this cleaner. I found that it works great on cleaning soldering irons, too.
The HCFC blend is non-flammable, non-hazardous, and compatible with metals and most elastomers. It's not safe for PVC, acrylic, or styrene plastics. But these plastics are rarely found on anything but consumer-grade tape and cassette decks, and not in the tape path. Also, it's not safe to drink. (Hey, we have to put it out there.) My only quibble is that the solution evaporates rapidly. So, don't leave the cap off! (From $6 direct; www.precisionmotorworks.com)
-Garrett Haines, www.treelady.com