[R-390] Resistor Tolerances

Mon, 29 Jul 2002 15:37:33 -0700 (PDT)

Or you could just run on-site poured babbit bearings!

Like they did in the old days.

(Clark)

Joe

--- "Scott, Barry (Clyde B)" <[email protected]> wrote:
> OK.  I suppose gasoline engines are different.
> 
> My experience comes from the manufacturing process
> for high-speed, precision punch presses.  There, you
> grind the shaft to a tolerance and bore the bushing
> to a tolerance for the necessary fit.  I suppose a
> gasoline engine may run with even tighter tolerances
> for the crankshaft, but we held some pretty tight
> ones for our presses.  Many of the bearing surfaces
> were hand scraped for fit as well as oil pockets. 
> It required quite some skill to do that right.  I
> ran the jig-borer before becoming an NC programmer. 
> Sometimes I miss those days...
> 
> Oh well, off-topic enough from me for one day.
> 
> Barry(III) - N4BUQ
> 
> (EMERSON)
> 
> > -----Original Message-----
> > From: Thomas W Leiper [mailto:[email protected]]
> > Sent: Monday, July 29, 2002 11:44 AM
> > To: [email protected]
> > Subject: Re: [R-390] Resistor Tolerances
> > 
> > 
> > On Mon, 29 Jul 2002 11:27:21 -0500 "Scott, Barry
> (Clyde B)"
> > <[email protected]> writes:
> > > Just curious:  How do you make a bearing
> clearance tighter 
> > once it's 
> > > bored too big (or the race is ground too small)?
> > 
> > We're talking about crank and rod bearings which
> consist
> > of half-shell inserts. Bearing inserts are
> designed to deliver
> > a certain clearance at a certain torque on the
> bearing cap
> > bolts, in other words they "squeeze" down to the
> tolerance.
> > You order undersized inserts (which are thicker)
> and then
> > reduce their length so they don't crush as much
> when you
> > torque down the bearing cap. If you are having
> your crank
> > turned (I recommend this treatment every night),
> you can
> > have the shop turn an "over"-undersize to tighten
> things up
> > as well if the availability of custom bearing
> inserts is poor.
> > 
> > Or, you can pick what's behind Door#3 ...A New Car
> !!
> > 
> > Hammarlund
> > _______________________________________________
> > R-390 mailing list
> > [email protected]
> > http://mailman.qth.net/mailman/listinfo/r-390
> > 
> _______________________________________________
> R-390 mailing list
> [email protected]
> http://mailman.qth.net/mailman/listinfo/r-390

__________________________________________________
Do You Yahoo!?
Yahoo! Health - Feel better, live better
http://health.yahoo.com