[TheForge] Re: Flatbelt excitement

[Ralph Sproul]

	Hi Mike, a tensioner is used in a flat belt when the machine has no clutch.
When dealing with a hammer like a Beaudry - you have to use on or the hammer
will run full time at full bore........   Or am I misunderstanding what you
did (which may be the case).  The A&O is a self contined correct?......so no
clutch required.

	The other thing about short belts with one pulley(drive) being smaller, and
the larger machine pulley being larger is it allows the belt to run on 2/3
of the surface of the pulley instead of 1/2 like a long drooping belt
would.........so the tensioner will allow a slight increase in the surface
the belt rubs on the drive pulley (especially if placed close enough to the
drive pulley to affect the wrap angle.

	Long belts are headaches as well due to humidity and sun increasing and
decreasing their length.  Synthetic belts are stable - but they grab more
than the leather ones.

	On a long belt (around said tree) an idler may be needed to take the droop
out of the belt in the span it crosses.

	Just some random thoughts on a Sat morning before heading to the shop

Ralph

-----Original Message-----
From: theforge-bounces at mailman.qth.net
[mailto:theforge-bounces at mailman.qth.net]On Behalf Of Mike Spencer
Sent: Friday, May 26, 2006 2:52 PM
To: theforge at mailman.qth.net
Subject: [TheForge] Re: Flatbelt excitement



> I have been planning to use flat belts in much lighter equipment,
> but hadn't considered a spring loaded idler to be needed; now I'll
> include one.

Well, I'm not sure just when an tensioner is useful (or not) or when
it's necessary (or not).  The problem only arises when the machine
can overrun -- run ahead of -- the belt. My 25# Jardine could do so in
theory but doesn't.  Typical flatbelt machinery -- saw mills, machine
tools, wood shop tools -- don't deliver a *constant* load but there's
no other power input so they always deliver *some* load.  But a single
vertical piston on a crank has power input from gravity.

Still thinking about it...
- Mike

--
Michael Spencer                  Nova Scotia, Canada       .~.
                                                           /V\
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^

_______________________________________________
Manage membership or unsubscribe at:
http://mailman.qth.net/mailman/listinfo/theforge
theforge mail list group photo site is
http://www.photoaccess.com
Login:  blacksmithblacksmith at hotmail.com
password:  anvil
___________