I've got one, its hard to finish a bore more accurately, straight and round. Great contraptions. Problem imo is the mandrels are stupidly expensive and each covers a very narrow range. I've three longer bores to do, needs the double stone length mandrel. Even took a shot at making some, then you realize why they are so expensive lol. There is no way I'm going spend that much so the machine sits as I often end up making laps instead.
Second problem is the mandrel and stone part numbering system. A huge designed effort was put into the specific goal of making me feel like an idiot. Never been able make sense out of it, just so frustrating to navigate. Phht, I'll make a lap.
Some good points .............
I don't know of a better way to finish a bore as straight and round as can be done with Sunnen equipment , I've personally used several different Sunnen machines . For years I never gave much thought to the numbering system or how difficult it is to understand , I simply used the mandrels and abrasives that were on hand , all of it was there and was applicable to the work I was doing . I was employed in a shop where all tooling and supplies were there for me and I wasn't involved with the aquisition of any of it .
THEN........ I bought my own machine and had to figure this numbering / grading system out . At first , I struggled with it , what was a real game changer was getting a few catalogs , where it's laid out pretty well and after a short time I had it figured out , well , a portion of it which included the mandrels / abrasives that were relevant to what I was doing . Sunnen made it easier to choose the correct tooling in the catalogs I have by devoting a section of the book to list the specialty tooling that they recommend for the work I am doing.
For a period of time I was buying lots of Sunnen tooling to outfit my machine , I made up a list of work I might have to do and decided what mandrels and abrasives I needed to get those jobs done . I found ebay to be a valuable source for the tooling I was looking for .
It's no secret that this stuff is not cheap and I must confess , I am guilty of getting carried away with buying more stuff than I should have . I'm the kind of guy that likes to be prepared and have the correct equipment available prior to starting the job . Knowing ahead of time what bore sizes I might be working on is what has enabled this . Typical work I might have going on is Motorcycle related , primarily , such as cylinder bores , bushing work , valve guides , connecting rods . I've been doing this long enough that I've got drivers that are portable , driven by a drill . The portable stuff is super expensive , even for used tooling.
I still look at Sunnen stuff on ebay every day ........ yes I have a wish list , abrasives are consumables , They wear out , you need to have back up .
Actively looking for anything Sunnen ......
