What are the parameters for knowing which one to use and for what duration?
Mfg. info in this older post
Timesaver comes in the 4 grades think analogy to just like sandpaper grades.
The lowest is for rough cutting...which I take to mean take off real high or wavy spots real quick and I wouldn't use it unless I had somewhere between .010"-.012" of surface clearance between the two parts to take off before I went to a finer polish.'
The second is for general lapping usually where a polish is not required.
The third starts a polished surface...
The fourth produces a micro polish.
Most don't but I do believe the intention of the original developer was to be like furniture finishing, you walk it in with the roughest that is still the quickest to get it to settle, and then go finer and finer until you get the surface finsih you want.
The super fine should give a near mirror finish when done and that may sound nice, but for these early splash oil systems there are times you can be too fine a surface finish as there is then nothing for the oil to cling to mechanically.
One of the claims to Timesaver is that time is not really part of the equation. It can't produce a surface better than it was designed for in the first place and they claim it all eventually goes benign. It's that eventually that troubles and confuses me as once you get that surface finish you want and if you still have live grit? There is nothing for it to do except bounce around. In a single exposed simple bearing mount, the answer IS so what. Where it can walk to other places I want to say Whoa, hold on a minute!
I'd actually cut is with a little more oil than they say, and the 'grit' just dies as it loses its sharp micro edges and as they claim becomes totally benign. Don't have the finish you want after the first? Do it again. Even though the grit dies and they claim you can leave it in...I'd flush it when done no matter what I used it for, why tempt fate?
Others will feel different, I'm sure Somewhere I have a graphic of some general micro grits blown up a bunch. I'll look for it later and if I find it, post it so you can see what live grit and dead grit looks like, and the graphic will let you see 'how' grit works.
What? No gallon of grey sludge coating everything inside the crankcase? Sorry. Couldn't help myself.
I do wipe mine back out when I get done. Like George, I don't think I want to tempt the fates. Time saver beats the heck out of scraping and you get a 100% bearing, not the 75% they say to try to get when scraping. Good stuff in my opinion.
Sounds like Timesaver is an awful lot like feldspar, the active part of Bon Ami. I've used Bon Ami in ATF to seat rings. Any problem using it to fit main and rod bearings?
Ralph - I think I wrote something about this some time ago, but many years ago, I worked with engineers and diesel mechanics and I actually learned a few things in the process (a few of those things I even remember,....ha,ha,....)
One thing I remember is that at one time, Caterpillar actually recommended the use of Bon Ami to aid in break-in and seating of new piston rings on diesel engine overhauls. Not sure when that was except it was many years ago and I'm not sure if that's still accepted practice or not; for what it's worth,......harold
Ralph, I kwen a guy a long time ago that used the same thing to seat rings. I thought he was nuts, but it worked.
"Knew" Can't type and talk at the same time.
Lewis Rector would tear a corner hole in a can of Bon Ami and dump it down the carb of a flathead with it running about half throttle. It belched and smoked and seated rings and cleaned up valves and all sorts of thing according to him. I've only done it once but it sure seemed to work.
Some things to think about:
If BonAmi works on cast iron and piston rings it is probably too hard for use with babbit. It has to break down and leave no abrasives when done.
Timesaver is available in four grades, what grade would Bon Ami be?
Timesaver is GUARANTEED NOT TO IMBED - WILL NOT CONTINUE TO CUT. Can you say that about Bon Ami
If I was buying some lapping compound I would use the correct grade or progression of finer grades of green or yellow timesaver as required.
When I first brought attention to Timesaver on this forum in about 2000, not one person in 50 on here knew what it was nor had they used it. It seems to have become ubiquitous amoung the T people now. I have had the same two cans for about 15 years now, the yellow is about half gone and the other can is still nearly full. It saves time and a little goes a long ways. As for Bon Ami, it was around and available before most people know Timesaver existed. They are both Feldspar, Bon Ami is very finely ground and as their can says, "It hasn't scratched yet." (That's way there is a baby chick on the can -- it hasn't scratched yet.)
By the way, I am still using the same can of "Separator Oil" that I started out with on the Timesaver. It is a can of old - probably 1940's - DeLavel oil for cream separators.
Stan, try some lucas oil stabilizer, seems to keep the time saver in the brgs. better. KB
Bon Ami won't scratch glass. In my book that's its claim to fame. I've used it several times to clean up antique window glass. Now I may try it on some steel and see what I get.
I found some at Ace today.
Timesaver is interesting stuff, approved by the military as I understand. It really does not polish a finish in fact it will dull it. It breaks down very fast so like fitting main bearings the cap is left a little loose while while turning and more timesaver is added after a short while. I use a cut down main shaft with a slow turning drill to speed the job. The drill will reverse, and has a high speed when the timesaver is broken mostly down. Green should not be used on babbitt, guess it cuts to fast.
Yellow 320 is what I use on babbitt and will use on transmission bushings. Brian Geranen from the timesaver web site is helpful, ships fast, and reasonable.
Paul, you are right in a sense, the green is made for hard metals and will embed in the babbitt and be with you always. Use only the yellow for babbitt. The bon ami will work also, We used to use it on friction bearing rail car journals to polish them out if they weren't rust etched to bad. Have fun, KB