[Supras] Lightweight flywheel+balancing

Thu Feb 1 16:17:33 CST 2007

Brandon and list:

    A lathe is the most basic of all machine tools.  South Bend and Logan
tend to be the least expensive on the used market.  They also are the
simplest, with stepped belt pullies, all in the open, somewhat antique
looking.  But they are fine to get the job done, and are not expensive.
Check the following link to a completed ebay sale:

http://cgi.ebay.com/METAL-LATHE_W0QQitemZ180074249751QQihZ008QQcategoryZ97230QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

You can generally find one with a 3 jaw self centering chuck, maybe a 4 jaw
independent chuck, tailstock center and maybe a steady rest for under $600
on ebay.  While not the nicest looking, a 9" South Bend in reasonable
condition will get the job done for most needs.  If needed you can get new
chucks from MSC or Enco for maybe $150.  Get end mills there too, maybe $4
for the imports.  The imported ones are fine, and are cheap.  Of course you
cannot refinish brake rotors on a 9" or 10" lathe because of the diameter,
but you can make small parts of most types with the addition of a milling
attachment.  That is a small vise with X-Y leadscrews which bolts to the
carriage of the lathe.  You put the end mill in the lathe chuck or collet.
It does not have the capability of a Bridgeport, but I used one for about 5
years when I got my first lathe in 1970.  Bought the Bridgeport 6 years
later for $600 (it needed work, but the price was right).  Over the years,
it becomes a matter of keeping your eyes open for tooling, like collet sets,
boring bars, and the like.  Flea markets, machine shops going out of
business, etc., are good sources.

You can also use the lathe as a horizontal drill press of sorts, up to the
size it will accommodate.

Over the years you will find yourself trading up.  The lathe I have here now
is a later 10" South Bend, with a more modern looking "underneath" drive for
the motor, and a long bed, important if you want to use the lathe as a pair
of bench centers for checking runout of a camshaft or crankshaft (at the
main journals) with a dial indicator (also cheap at Enco, maybe $12 to $30
with a magnetic base, made in China, but their stuff is much better than it
was a couple of years ago).  It is one model before the one shown in the
following link, but has a 48" long bed rather than a 32" bed:

http://cgi.ebay.com/SOUTHBEND-10-x-32-Engine-Lathe_W0QQitemZ140074118182QQihZ004QQcategoryZ97230QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Just about all lathes have "change gears" as a minimum so you can cut
threads using the leadscrew (visible in the photo).  The better ones have a
"quick change gearbox" with levers you set to set the thread pitch you cut.
So if you don't have a die or tap for a specific size thread, you can lathe
cut it (with some patience, but it will get the job done).

These are tools you will have all of your life.  You will find yourself
using them for all sorts of things aside from cars.  For example, recently I
had to modify half of a a copper tubing union to be a 1/2" male pipe to 1/2"
(actually 5/8" OD) copper sweat fitting.  Feel free to ask any further
questions.  See if your local library has a paperbound book written by South
Bend titled "How to Run a Lathe".  Copies show up on ebay also.  It is
invaluable.

        BernieK

----- Original Message ----- 
From: "Brandon" <fstrnldr at tconl.com>
To: <berniek at technicaldevelop.com>
Cc: <berniek at technicaldevelop.com>; <supras at supras.com>
Sent: Thursday, February 01, 2007 2:10 PM
Subject: Re: [Supras] Lightweight flywheel+balancing

> Oh trust me i go through this stuff again and again w/ local machine
shops.
> Two days ago i picked up a 3SGTE head off an alltrac, and the surface job
> looked like crap on one side,   i was told oh its the heat treat thats
baked
> out of the head, thats the best that you can do, maybe try some silver
paint
> before you put gasket on.   I took it to a scond shop that cleaned it up
and
> when i picked it up i took it back to the first shop, and got "well i
think
> we had it smoother on the intake side, but the exhaust looks better for
> sure"    no offer of money back, or anything like that.    If i really
want
> my machine work done right i crate the parts up and ship them out to now
> idaho, used to be so cal.
>
> anyway i just had to throw out the machine shop thing because well not
> everyone has a lathe handy.   I wish i did. though.
> ----- Original Message ----- 
> From: <berniek at technicaldevelop.com>
> To: "Brandon" <fstrnldr at tconl.com>
> Cc: <berniek at technicaldevelop.com>; <supras at supras.com>
> Sent: Thursday, February 01, 2007 8:56 AM
> Subject: Re: [Supras] Lightweight flywheel+balancing
>
>
> > Yes, you are right on the premise that you think they will be careful.
No
> > doubt there are some, like the one in Oklahoma (R&L Machine?) used by
> > Arelene Lanman.  However, I found years ago that having a lathe and
> > Bridgeport, welding equipment saved a LOT of time waste, and doubts
about
> > quality of work done outside.
> >
> > I did find a decent shop to do some work, and had them resurface the
head
> > and block.  But I've also seen too many instances where shops are a bit
> > careless.  As an example, a shop would not refinish camshaft bearing
caps,
> > which I've done and have written about on this list.  They don't want to
> > understand that all of the wear is in the caps, and instead they talk
> > abopu align boring the cam journals, expensive and not necessary.
> >
> > Getting the valve clearances right was a pain, and I can't imagine most
> > shops taking the time to do what we all read about with port cleanup,
> > correct valve jobs, and the patience to set clearances in shim and
bucket
> > engines.  No doubt good shops exist, but here in North Central NJ they
> > seem few and far between.
> >
> > Although the owner of the best shop I've found in Morris County NJ
always
> > has a can of beer in his hand, he seems to not let it get to his head.
> > The flatness of the head and block I can check with a precision
> > straightedge and feeler gauges.  Checking of flywheel and clutch I
cannot
> > do without making up the ring anyway.
> >
> > Making up the adapter ring for ball bearing to pilot hole adaptation on
> > the lathe takes about 20 minutes.
> >
> >       BernieK
> >
> >> or you could just drop it off at a machine shop ;-)
> >>
> >>
> >> ----- Original Message -----
> >> From: <berniek at technicaldevelop.com>
> >> To: <Supras at supras.com>
> >> Sent: Wednesday, January 31, 2007 5:59 PM
> >> Subject: Re: [Supras] Lightweight flywheel+balancing
> >>
> >>
> >>> While not as light as an aluminum flywheel, I got a chrome-moly
flywheel
> >>> from AutoCom.  It a lot lighter than the cast iron stocker, and much
> >>> stronger.  The price was right, too, about half the cost of aluminum.
> >>> It
> >>> still needs to be installed as part of my JDM rebuild, now over a year
> >>> old
> >>> due to work considerations.
> >>>
> >>> When the inertia of the pressure plate is considered, the difference
in
> >>> total angular inertia of the flywheel and clutch combination will not
be
> >>> that much different than with use of an aluminum flywheel.
> >>>
> >>> Just a suggestion:  If you have a lathe, make up a ring which fits the
> >>> center hole of the new flywheel and a small ball bearing in the
center.
> >>> If the ball bearing is sealed, take out the seals and grease, and put
> >>> clean oil in the bearing to minimize drag.  Put the ring and ball
> >>> bearing
> >>> in, put a shaft in the ball bearing, and stick the other end of the
> >>> shaft
> >>> in a vise.  The heavy side of the flywheel will roll to the bottom.
> >>> With
> >>> a Dremel tool, you can remove material from the heavy side to the
point
> >>> where you can make the flywheel stop at any point, so its balanced.
> >>> Then
> >>> bolt the pressure plate on, and repeat the process with it.  Punch
mark
> >>> them so they will go together during installation the same way.
> >>>
> >>> There is a way to do balancing in the car as well, which I did when
> >>> putting an aluminum flywheel in my Chevy powered Firebird.  Run the
> >>> engine
> >>> at the speed where the vibration is worst to get an idea of the
> >>> vibration
> >>> magnitude.  Then take the access cover off the bell housing, take out
> >>> one
> >>> pressure plate bolt, put a couple of washers under it, and reinstall
it.
> >>> Run the engine again, and see if the vibration has gotten worse or
> >>> better.
> >>> Try this with each of the pressure plate bolts in sequence until you
> >>> find
> >>> the one or two at which the vibration is minimized.  Then change the
> >>> number of washers to obtain minimum vibration.  That worked like a
> >>> charm.
> >>> At one time I believe I saw a GM bulletin describing the same
procedure
> >>> for balancing a Buick flex plate and torque convertor.
> >>>
> >>>            BernieK
> >>> _______________________________________________
> >>> Supras mailing list
> >>> Supras at supras.com
> >>> http://supras.com/mailman/listinfo/supras_supras.com
> >>
> >>
> >
>
>
>