On Tue, 18 Nov 2008 17:41:10 -0800, "Bill Noble"
wrote:


snip-

2. belt - Abene says they used both V and flat belts on this machine -
mine
has triple V belts to drive the spindle and a single flat belt to drive
the
table gearbox - the flat belt sheaves, measured at the crown are 88 mm
(about 3.5 inches) and 51 mm (about 2 inches) - I'm thinking of changing
to
a J series micro-V belt - any thoughts on this idea? I guess I could
change
to a V belt - it only needs to hold 2 HP after all.

3 the original flat belt is 40 inches X 1 inch - does that size seem
standard? The belt in there now is a Gates SpeedFlex, which is long
obsolete. Any thoughts other than using a microV belt?


** Posted from http://www.teranews.com **

From SKF's site, the seal is a CR 17X35X10 CRSA1 R, US stock no.6712.
For the belt, I'd download Gates' belt sizing app. The micro v sounds
more likely to fit in the same space as the flat belt than a standard
V.

Regards,

Pete Keillor

Thanks, I'd forgotten about SKF, I'll see if that seal is easy to get -
right now I've machined a ring and used an oil pump seal that is common

as for the belt - I really really REALLY want to forever solve the problem
of the belt slipping off the sheaves - I don't mind it slipping - in fact,
that is a safety feature - so far, I'm thinking of using the Gates micro-V
belt (specifically 400J10) and I am thinking I'll make new sheaves since
that is a good use for my lathe and it will be a permanent solution - the
other possibility is to add a lip to the existing flat belt sheaves so that
the belt can't slip off under overload.

thoughts? remarks?

Personally I think that going poly-v is overboard here. I've never
had the belt slip off mine since putting a poly-v belt on backwards on
the flat belt pulleys that are there. I'm trying to remember if it
came off before that. It might have but the reason for changing was
because the original broke. When we changed mine we originally ordered
a toothed belt and put it on flat side in. But it was to short and
when I stretched it over the pulleys it made a lot of noise. So we
went to the local parts store a found a poly-v for a car that was the
right length. We put it on inside out and it's been fine since. That
was at least 10 years ago.

As for the pulleys I don't recommend machining flanges. Unless
they're very tall they're more likely to make the belt come off. The
crown on the pulleys will keep the belt pulled to center if it's tight
enough to run properly.

I did ask the factory in sweeden about this, they suggested replacing the
belt - do you guys believe that a belt replacement alone will fix the
problem? the old belt is thin woven fiber and it's oily so it is slippery,
but I tried removing it and cleaning the belt and the sheaves and it still
slipped off. On this machine, putting the belt on is something of an ordeal
because I have to remove a cover over the power control relays, unbolt the
relay assembly and swing it out of the way, and then reach into a hole in
the base of the mill to put the belt back on (and then reassemble
everything) - it's not like a lathe with a flat belt where you just reach
over and put it back in place

I agree on the pain of replacing that belt. I remember the problems
I had changing mine.