Isopropyl alcohol would be a sensible guess, I've not seen that abbreviation before though . - H On Sat, Jan 27, 2018, 18:24 Adrian Stoness via cctech <cctech at classiccmp.org> wrote: > ipa as in beer? > > On Sat, Jan 27, 2018 at 12:17 PM, Carl Claunch via cctech < > cctech at classiccmp.org> wrote: > >> The IPA is heated to 60C before the ultrasound is able to remove the > oxide >> remnants, FWIW. >> >> While we can often get the entire smooth surface of the head clean with >> swabs and IPA, it is very difficult to clean all the material that forms > in >> the cruciform trench recessed into the head (where the read/write and > erase >> coil poles are visible). >> >> Heads can seem clean to the naked eye, but a good stereo microscope will >> insure that you have a clean and smooth surface. >> >> Regards, >> Carl >> >> Date: Fri, 26 Jan 2018 12:15:34 -0800 >>> From: Fritz Mueller <fritzm at fritzm.org> >>> To: "General Discussion: On-Topic and Off-Topic Posts" >>> <cctalk at classiccmp.org> >>> Subject: ultrasonic cleaning for disk heads >>> Message-ID: <9F2C2AC7-1B35-46F5-BD92-CC3DFD29FBFA at fritzm.org> >>> Content-Type: text/plain; charset=utf-8 >>> >>> I watched with great interest one of curiousmarc?s recent Alto videos, >>> wherein they clean a Diablo drive head ultrasonically. I?ve been >>> struggling a bit with my restored RK05 drives to completely clean the >> heads >>> after minor head crashes. Not being able to get them really sparkling >>> clean makes me always worried about running the drives for more than a >> few >>> minutes at a time, and a little nervous every time I spin them up?. >>> Scrubbing and scrubbing and scrubbing with IPA and kimwipes just > doesn?t >>> seem to get all the crud off. >>> >>> I do have an alignment pack that I could use to re-align the heads > after >>> removing them for a proper cleaning this way. Decent ultrasonic > cleaners >>> aren?t terribly expensive and might be nice to have around the shop >> anyway >>> (I could also do all my eyeglasses :-) >>> >>> In the video, the heads are submerged in IPA in a glass cylinder, which >> is >>> then placed in the ultrasonic bath. >>> >>> Has anybody on the list here done this and have tips/advice beyond what >>> can be seen in the video? It looked very effective! I?m also having a >>> little trouble sourcing the squat form glass graduated cylinder online. >>> >>> cheers, >>> ?FritzM. >>> >>>