C.C.T.

Awe !! I wanna play too !! I've ordered a 12" length of 1-3/8" Acetal Rod 150 which is also commonly known as Delrin 150 from Acklands Grainger for the cost of $21 Canadian. and I've also got J78 needle bearings coming in from Oshawa bearing. I'll fire up the lathe and part off some Delrin tires and press fit the J78 bearings in to them. I'll have to do some testing to figure out the interference fit required, since the coefficient of linear expansion of Delrin doesn't seem to be reasonably available. Should be as simple as roughing out the the Delrin tire and dropping it in boiling water and measuring the change in bore diameter, then figuring out what to bore the tire to. I'll do this as a "Proof of Concept" option. it's the kind of thing that challenges me and put a smile on my face.
I ordered the Delrin a week ago and it's coming up from Chicago so it's going to be a while in shipping. (Border, Covid).
Also going to check the tool box and see if I have an adjustable reamer for a 14.99 mm size. if I do, I'll also order a Z1000 guide roller and modify it for the J78 bearing. That job would be a 1/2 hour job for me on a good drill press or a simple mill. Clamping down the roller on a mill table or drill press table is easy enough. Standard milling machine table clamps will suffice. As far as removing the rubber guide down the center of the tire, I have a tool post grinder for. the lathe that would buff that off nicely.

kawboy;  You may have a side-business !

I just ordered one of the vintage rollers.  2 weeks if I'm lucky !    That's $100.00cdn incl. shipping, so far.  Machine shop $ - ?

kawboy:  I initially had some concerns about chain drift but have dismissed it.  The 3 chain-guides look new !  The original rubber roller had worn into the center of the tire about .5mm.  The approx. 1mm shoulder on each side had virtually no marks of any kind, indication no chain drift.
Sorry 'bout the crappy picture.  This is the one that I should have deleted !  

 

A lathe - how I envy you Kawboy.   What make / type / size is it please?

I'm looking forward to seeing the result of your endeavours. By one means or another, it seems that the tensioner roller problem will be overcome. This is really interesting!  "Necessity is the mother of invention."

Your recounting the incident of the lack of jacking oil pressure on those turbo generator shaft bearings reminds me of a magazine road test many years ago comparing the Suzuki GS550 and the Kawasaki KZ650.  For some now-forgotten reason, the Suzuki suffered a loss of oil pressure.  Though the engine was being run hard at the time, and was not stopped immediately, it apparently suffered no damage. The point was made that, had it been the Kawasaki losing oil pressure, the plain crank bearings would likely have been damaged. However, the Suzuki, having a roller bearing crank, could tolerate a lack of oil flow for much longer.   

It's just a little 7"x24" atlas lathe. I have it mounted on a tool box. Here's a pic of it with a camshaft chucked up and one of my many attempts at tooling up to grind camshaft profiles. It's a cute little $400 experiment. It has a carriage feed that's adjustable by changing out various gears. When I got it, I just wanted one big enough to play on and not take up too much space in the shop. Just something to doink around on.