I need to know the exact gearing ratio for my mill in backgear. This is for
a gear hobbing project I hope to finish within the next X years (X has been
less than one for a couple years now)

Anyway, I have an encoder on my drive spindle that does 4000 counts per
turn. I ran the machine in backgear exactly 100 revolutions and got
2,451,765 pulses. I didn't use an indicator for the begin or end stop point
(mark at end of 4" fly cutter lined up) so the true total could be +/- 250
pulses

This gives a gear ratio of 6.1294. I need a really good guess on the number
of teeth in the drive and driven gear. For example, if the drive gear has 10
teeth and the driven gear has 60 teeth, the ratio would be exactly 6.00.
There's a zillion possibles, I'm looking for one that give a number within a
couple tenths(.0002) of this ratio.

If I have too, I'll tear the machine down. But, I'm hoping there's a math
genious out there. If needed, I could put a counter on the spindle and do
1000 turns.

Karl

Karl Townsend wrote:

I need to know the exact gearing ratio for my mill in backgear. This is for
a gear hobbing project I hope to finish within the next X years (X has been
less than one for a couple years now)

Anyway, I have an encoder on my drive spindle that does 4000 counts per
turn. I ran the machine in backgear exactly 100 revolutions and got
2,451,765 pulses. I didn't use an indicator for the begin or end stop point
(mark at end of 4" fly cutter lined up) so the true total could be +/- 250
pulses

This gives a gear ratio of 6.1294. I need a really good guess on the number
of teeth in the drive and driven gear. For example, if the drive gear has 10
teeth and the driven gear has 60 teeth, the ratio would be exactly 6.00.
There's a zillion possibles, I'm looking for one that give a number within a
couple tenths(.0002) of this ratio.

If I have too, I'll tear the machine down. But, I'm hoping there's a math
genious out there. If needed, I could put a counter on the spindle and do
1000 turns.

Karl

49:8? Unlikely, but that gives 6.125, error of only .016% .. - GWE

Karl,

Since there aren't many choices of small gear size lets do this the brute
force way
and just bang the first few reasonabley sized gears by the ratio on a
calculator

The * indicates it a prime number

6.129 times

8 =49.032 = 8x49 = 6.125
*9 =55.161 = 9x55 = 6.1111111
10=61.29 = 10x61 = 6.1
*11=67.419 = 11x67 = 6.0909090
12=73.548 = 12x73 = 6.0833333
*13=79.677 = 13x80 = 6.1538462
14=85.806 = 14x85 = 6.0714286
15=91.935 = 15x91 = 6.0666666
16=98.064 = 16x98 = 6.125
*17=104.193 = 17x104= 6.1176471
18=110.322 = 18x110= 6.1111111
*19=116.451 = 19x116= 6.1052632

My bet is that it's a 6.125 ratio.. Note it's NOT prime but neither is my
Bridgeport (it's 8.25)
And I also bet it's the 16x98 gearset and not the 8x49... just a hunch....
I doubt the pinion is much bigger than 19 or 20 teeth because of the
physical size that the big get winds up being.
Good luck ( and I'd dissassemble the machine and count teeth)
Oh and what make of machine is this, I bet some google time would find the
'right' answer...

Dave


"Karl Townsend" remove .NOT to reply wrote
in message hlink.net...
I need to know the exact gearing ratio for my mill in backgear. This is for
a gear hobbing project I hope to finish within the next X years (X has been
less than one for a couple years now)

Anyway, I have an encoder on my drive spindle that does 4000 counts per
turn. I ran the machine in backgear exactly 100 revolutions and got
2,451,765 pulses. I didn't use an indicator for the begin or end stop
point (mark at end of 4" fly cutter lined up) so the true total could be
+/- 250 pulses

This gives a gear ratio of 6.1294. I need a really good guess on the
number of teeth in the drive and driven gear. For example, if the drive
gear has 10 teeth and the driven gear has 60 teeth, the ratio would be
exactly 6.00. There's a zillion possibles, I'm looking for one that give a
number within a couple tenths(.0002) of this ratio.

If I have too, I'll tear the machine down. But, I'm hoping there's a math
genious out there. If needed, I could put a counter on the spindle and do
1000 turns.

Karl

,,,

My bet is that it's a 6.125 ratio.. Note it's NOT prime but neither is my
Bridgeport (it's 8.25)


I'm certain its slightly different from 6.125, that was my first estimate.
This is (6.125*4000*100) = 2,450,000 counts. I had 1765 counts more than
this in 100 turns, or nearly 1/2 a revolution of the spindle.

The machine is an Excello model 602. An Excello looks like a bridgeport J
head on steroids. Made in Canada. I've never found a manual for it.

Karl

Don't want to get into '****ing on trees' but an excello 602 is a BP clone
and the stock model weighs in at about #300 less than a BP..
I've seen a 602 run and .. no big deal.. (not to say I haven't seen some
kickass Excello machines)

But back to your problem... You have my table of likely gear ratios.. pick
which one suites you, next closest is 13x80, which *could* be in the ball
park, but just as far off on the other end... There isn't any magic here,
you see the ratios that are generated,... "ya pays yer money and ya takes
yer chances"

I also have trouble with your statment
" I had 1765 counts more than this in 100 turns, or nearly 1/2 a revolution
of the spindle"
If I read you origonal post correctly thats 1765 counts in 100 turns or
17.65 counts in ONE turn.. Hmmm that sure sounds like 6.125 to me.. but hey
I just own a wimpy Bridgeport....

Dissasemble and count teeth......... and let Grant and I know when it comes
up 6.125 :-)

Dave



"Karl Townsend" remove .NOT to reply wrote
in message link.net...

,,,

My bet is that it's a 6.125 ratio.. Note it's NOT prime but neither is my
Bridgeport (it's 8.25)


I'm certain its slightly different from 6.125, that was my first estimate.
This is (6.125*4000*100) = 2,450,000 counts. I had 1765 counts more than
this in 100 turns, or nearly 1/2 a revolution of the spindle.

The machine is an Excello model 602. An Excello looks like a bridgeport J
head on steroids. Made in Canada. I've never found a manual for it.

Karl

My bet is that it's a 6.125 ratio.. Note it's NOT prime but neither is my
Bridgeport (it's 8.25)


I'm certain its slightly different from 6.125, that was my first estimate.
This is (6.125*4000*100) = 2,450,000 counts. I had 1765 counts more than
this in 100 turns, or nearly 1/2 a revolution of the spindle.

The machine is an Excello model 602. An Excello looks like a bridgeport J
head on steroids. Made in Canada. I've never found a manual for it.

Karl

Sorry to reply to my own post. I used Excel to follow this idea. 31*6.1294 =
190.01 or almost identical to my measuremnets.

I've never had a 1J style head apart. Any chance they use gears with this
many teeth, 31 driving 190?

Karl

On Fri, 18 Mar 2005 22:17:32 GMT, "Karl Townsend"
remove .NOT to reply wrote:

This gives a gear ratio of 6.1294. I need a really good guess on the number
of teeth in the drive and driven gear. For example, if the drive gear has 10
teeth and the driven gear has 60 teeth, the ratio would be exactly 6.00.
There's a zillion possibles, I'm looking for one that give a number within a
couple tenths(.0002) of this ratio.

What you need to do is a continued fraction expansion of 6.1294. Using the
program on my site, I get:

RATIONAL FRACTION APPROXIMATION

Number to approximate ? 6.1294
Desired approximation accuracy [0.01 %] ?

Number = 6.1294
6 & 11/85 = 521/85 = 6.129411765
Approximation Error = 0.00909174 %

A 521:85 gear ratio sounds mighty unlikely. I suspect you need to determine the
numerical value more accurately.

Regards, Marv

Home Shop Freeware - Tools for People Who Build Things
http://www.geocities.com/mklotz.geo


--
HSM Freeware Programs at
http://www.geocities.com/mklotz.geo

In article k.net,
says...


My bet is that it's a 6.125 ratio.. Note it's NOT prime but neither is my
Bridgeport (it's 8.25)


I'm certain its slightly different from 6.125, that was my first estimate.
This is (6.125*4000*100) = 2,450,000 counts. I had 1765 counts more than
this in 100 turns, or nearly 1/2 a revolution of the spindle.

The machine is an Excello model 602. An Excello looks like a bridgeport J
head on steroids. Made in Canada. I've never found a manual for it.

Karl

Sorry to reply to my own post. I used Excel to follow this idea. 31*6.1294 =
190.01 or almost identical to my measuremnets.

I've never had a 1J style head apart. Any chance they use gears with this
many teeth, 31 driving 190?


The J head has a double reduction. The first stage is a timing belt, the
second is a pinion driven by the larger timing belt sprocket which
drives the bull gear on the spindle.

The total ratio for a 1J is 8-1/4:1 - I don't know whether that's exact
or not. I do have a couple exploded views and photographs of the parts
in question from old BP manuals, so it would probably be possible to
count teeth on the various pulleys and gears, but I'm not sure it would
be much help in figuring out your Excello.

Ned Simmons

Karl, can you contact Excello?

Are you positive you have just one set of gears operating here?

Grant

Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual. I've been
lucky and never needed special parts. But, I bet the parts manual won't show
enough detail to count teeth. By chance, does anyone know where they are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J style
head.

Right now, I'm a cogitatin' on how to mount an encoder in a tool holder.
Then run the machine and get the ratio out to the sixth decimal place. Seems
easier than tearing it down. Then use that real nice gear calculator Marvin
offered.

Karl

Karl Townsend wrote:
My bet is that it's a 6.125 ratio.. Note it's NOT prime but neither is my
Bridgeport (it's 8.25)


I'm certain its slightly different from 6.125, that was my first estimate.
This is (6.125*4000*100) = 2,450,000 counts. I had 1765 counts more than
this in 100 turns, or nearly 1/2 a revolution of the spindle.

The machine is an Excello model 602. An Excello looks like a bridgeport J
head on steroids. Made in Canada. I've never found a manual for it.

Karl


Sorry to reply to my own post. I used Excel to follow this idea. 31*6.1294 =
190.01 or almost identical to my measuremnets.

I've never had a 1J style head apart. Any chance they use gears with this
many teeth, 31 driving 190?

Karl



The Bridgeport 1J and 2J use 2 stages. There is a toothed belt with a
small sprocket on the driven pulley and a great big sprocket behind it
that turns the back gear's pinion. Then, the pinion turns the big
bull gear below the driven pulley. The center of the bull gear is the
female spline that drives the spindle spline.

Jon

Karl
I have a manual for my 602 and it will be no help in determining gear
tooth counts. Just has a cut away view to identify parts. The
machine uses a double reduction gearsets.

Be careful if you disassemble the head. I had mine apart and
replaced all the bearings and seals. When putting it back together
the meshing of the plastic spindle feed gear is critical. If not
meshed with the mating steel gear, guess what happens to the little
$350 gear. The "second time' I used spacers to slowly lower the
castings together while meshing the gears.

Good luck

John Normile



On Sat, 19 Mar 2005 02:39:34 GMT, "Karl Townsend"
remove .NOT to reply wrote:

Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual. I've been
lucky and never needed special parts. But, I bet the parts manual won't show
enough detail to count teeth. By chance, does anyone know where they are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J style
head.

John,

Cam I email you a pic of my machine? Based on another poster, I may have the
model number wrong. My CNC machine has a Taper 40 spindle, is a bit larger
than a 2J Bridgeport, and has a 2J style head. Sound like yours? My machine
has a serial no. but can't find a model number on it.

BTW, I need to do the same job. My machine drips oil on the table. Maybe 1
drip per hour, but its a mess after a couple of weeks with no use. Thanks
for the heads up.

Karl




"John Normile" wrote in message
. ..
Karl
I have a manual for my 602 and it will be no help in determining gear
tooth counts. Just has a cut away view to identify parts. The
machine uses a double reduction gearsets.

Be careful if you disassemble the head. I had mine apart and
replaced all the bearings and seals. When putting it back together
the meshing of the plastic spindle feed gear is critical. If not
meshed with the mating steel gear, guess what happens to the little
$350 gear. The "second time' I used spacers to slowly lower the
castings together while meshing the gears.

Good luck

John Normile



On Sat, 19 Mar 2005 02:39:34 GMT, "Karl Townsend"
remove .NOT to reply wrote:

Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual. I've
been
lucky and never needed special parts. But, I bet the parts manual won't
show
enough detail to count teeth. By chance, does anyone know where they are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J style
head.

My model 602 is in exactly the same condition. (1 drip / hour plus or
minus). So I've been all ears lurking on this thread. If you find the source
for the manual, please mail me or publish it here.

Thanks,

Adam Smith
Midland ON

"Karl Townsend" remove .NOT to reply wrote
in message k.net...
John,

Cam I email you a pic of my machine? Based on another poster, I may have
the model number wrong. My CNC machine has a Taper 40 spindle, is a bit
larger than a 2J Bridgeport, and has a 2J style head. Sound like yours? My
machine has a serial no. but can't find a model number on it.

BTW, I need to do the same job. My machine drips oil on the table. Maybe 1
drip per hour, but its a mess after a couple of weeks with no use. Thanks
for the heads up.

Karl




"John Normile" wrote in message
. ..
Karl
I have a manual for my 602 and it will be no help in determining gear
tooth counts. Just has a cut away view to identify parts. The
machine uses a double reduction gearsets.

Be careful if you disassemble the head. I had mine apart and
replaced all the bearings and seals. When putting it back together
the meshing of the plastic spindle feed gear is critical. If not
meshed with the mating steel gear, guess what happens to the little
$350 gear. The "second time' I used spacers to slowly lower the
castings together while meshing the gears.

Good luck

John Normile



On Sat, 19 Mar 2005 02:39:34 GMT, "Karl Townsend"
remove .NOT to reply wrote:

Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual. I've
been
lucky and never needed special parts. But, I bet the parts manual won't
show
enough detail to count teeth. By chance, does anyone know where they are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J style
head.

I have owned 2 Bridgeport J-heads and they both drip oil. I believe this
may be normal behavior. I think the oiling system on these is completely
lossy. You put oil in, it runs out .. - GWE

Adam Smith wrote:
My model 602 is in exactly the same condition. (1 drip / hour plus or
minus). So I've been all ears lurking on this thread. If you find the source
for the manual, please mail me or publish it here.

Thanks,

Adam Smith
Midland ON

"Karl Townsend" remove .NOT to reply wrote
in message k.net...

John,

Cam I email you a pic of my machine? Based on another poster, I may have
the model number wrong. My CNC machine has a Taper 40 spindle, is a bit
larger than a 2J Bridgeport, and has a 2J style head. Sound like yours? My
machine has a serial no. but can't find a model number on it.

BTW, I need to do the same job. My machine drips oil on the table. Maybe 1
drip per hour, but its a mess after a couple of weeks with no use. Thanks
for the heads up.

Karl




"John Normile" wrote in message
t...

Karl
I have a manual for my 602 and it will be no help in determining gear
tooth counts. Just has a cut away view to identify parts. The
machine uses a double reduction gearsets.

Be careful if you disassemble the head. I had mine apart and
replaced all the bearings and seals. When putting it back together
the meshing of the plastic spindle feed gear is critical. If not
meshed with the mating steel gear, guess what happens to the little
$350 gear. The "second time' I used spacers to slowly lower the
castings together while meshing the gears.

Good luck

John Normile



On Sat, 19 Mar 2005 02:39:34 GMT, "Karl Townsend"
remove .NOT to reply wrote:


Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual. I've
been
lucky and never needed special parts. But, I bet the parts manual won't
show
enough detail to count teeth. By chance, does anyone know where they are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J style
head.

On Sun, 20 Mar 2005 11:37:08 -0800, Grant Erwin
wrote:

I have owned 2 Bridgeport J-heads and they both drip oil. I believe this
may be normal behavior. I think the oiling system on these is completely
lossy. You put oil in, it runs out .. - GWE

Ayup. Total loss system. If it stops dripping on your table...you are
out of oil.

Put a rag down under the quill if it bothers you. The seals, such as
they are, may be worn, but its a normal thing. Most machine tools of
this vintage are this way.

My big old Gorton MasterMill ****es all over the place and it was
rebuilt not long before I got it. Shrug..nature of the beast. The
only way to slow the drip down, is go to a higher visc oil. Then you
are on your own.

Gunner


Adam Smith wrote:
My model 602 is in exactly the same condition. (1 drip / hour plus or
minus). So I've been all ears lurking on this thread. If you find the source
for the manual, please mail me or publish it here.

Thanks,

Adam Smith
Midland ON

"Karl Townsend" remove .NOT to reply wrote
in message k.net...

John,

Cam I email you a pic of my machine? Based on another poster, I may have
the model number wrong. My CNC machine has a Taper 40 spindle, is a bit
larger than a 2J Bridgeport, and has a 2J style head. Sound like yours? My
machine has a serial no. but can't find a model number on it.

BTW, I need to do the same job. My machine drips oil on the table. Maybe 1
drip per hour, but its a mess after a couple of weeks with no use. Thanks
for the heads up.

Karl




"John Normile" wrote in message
et...

Karl
I have a manual for my 602 and it will be no help in determining gear
tooth counts. Just has a cut away view to identify parts. The
machine uses a double reduction gearsets.

Be careful if you disassemble the head. I had mine apart and
replaced all the bearings and seals. When putting it back together
the meshing of the plastic spindle feed gear is critical. If not
meshed with the mating steel gear, guess what happens to the little
$350 gear. The "second time' I used spacers to slowly lower the
castings together while meshing the gears.

Good luck

John Normile



On Sat, 19 Mar 2005 02:39:34 GMT, "Karl Townsend"
remove .NOT to reply wrote:


Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual. I've
been
lucky and never needed special parts. But, I bet the parts manual won't
show
enough detail to count teeth. By chance, does anyone know where they are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J style
head.





Every normal man must be tempted, at times, to spit on his hands, hoist the black flag, and begin slitting throats.
H. L. Mencken

Well, you learn something most every day, don't you? Thanks, both, for the
information. I must say that the mill runs like a train, the only thing that
had me bothered about the oil drip was the notion that "it shouldn't be
doing that".

Anyone know what the recommended lube for the head on and XLO 602 is?

Adam Smith,
Midland, ON

"Gunner" wrote in message
...
On Sun, 20 Mar 2005 11:37:08 -0800, Grant Erwin
wrote:

I have owned 2 Bridgeport J-heads and they both drip oil. I believe this
may be normal behavior. I think the oiling system on these is completely
lossy. You put oil in, it runs out .. - GWE

Ayup. Total loss system. If it stops dripping on your table...you are
out of oil.

Put a rag down under the quill if it bothers you. The seals, such as
they are, may be worn, but its a normal thing. Most machine tools of
this vintage are this way.

My big old Gorton MasterMill ****es all over the place and it was
rebuilt not long before I got it. Shrug..nature of the beast. The
only way to slow the drip down, is go to a higher visc oil. Then you
are on your own.

Gunner


Adam Smith wrote:
My model 602 is in exactly the same condition. (1 drip / hour plus or
minus). So I've been all ears lurking on this thread. If you find the
source
for the manual, please mail me or publish it here.

Thanks,

Adam Smith
Midland ON

"Karl Townsend" remove .NOT to reply
wrote
in message k.net...

John,

Cam I email you a pic of my machine? Based on another poster, I may have
the model number wrong. My CNC machine has a Taper 40 spindle, is a bit
larger than a 2J Bridgeport, and has a 2J style head. Sound like yours?
My
machine has a serial no. but can't find a model number on it.

BTW, I need to do the same job. My machine drips oil on the table. Maybe
1
drip per hour, but its a mess after a couple of weeks with no use.
Thanks
for the heads up.

Karl




"John Normile" wrote in message
. net...

Karl
I have a manual for my 602 and it will be no help in determining gear
tooth counts. Just has a cut away view to identify parts. The
machine uses a double reduction gearsets.

Be careful if you disassemble the head. I had mine apart and
replaced all the bearings and seals. When putting it back together
the meshing of the plastic spindle feed gear is critical. If not
meshed with the mating steel gear, guess what happens to the little
$350 gear. The "second time' I used spacers to slowly lower the
castings together while meshing the gears.

Good luck

John Normile



On Sat, 19 Mar 2005 02:39:34 GMT, "Karl Townsend"
remove .NOT to reply wrote:


Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual.
I've
been
lucky and never needed special parts. But, I bet the parts manual
won't
show
enough detail to count teeth. By chance, does anyone know where they
are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways
back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J
style
head.





Every normal man must be tempted, at times, to spit on his hands, hoist
the black flag, and begin slitting throats.
H. L. Mencken

Seals?

The BP J head is just like an old Triumph or Harley Davidson 'chain' oiler..
it's 'supposed' to leak...

If ya own a BP, look up under at the 'spindle nose'... See those 2 'spanner
wrench holes'... they are 3/16 with a 1/8 hole all the way through to the
bearing races... All that oil you put in the oil cups at the top comes out
there... it's good practice to stick a pipe cleaner or something like that
up there every once and while to make sure they are clear...

and heck, having it drip oil in my table just saves me from squirting some
on there to keep it from rusting.

BTW this also means that if you don't use the machine every day you should
run it slowly and oil it well for a many minutes before ya do some serious
work.

Dave


"Gunner" wrote in message
...
On Sun, 20 Mar 2005 11:37:08 -0800, Grant Erwin
wrote:

I have owned 2 Bridgeport J-heads and they both drip oil. I believe this
may be normal behavior. I think the oiling system on these is completely
lossy. You put oil in, it runs out .. - GWE

Ayup. Total loss system. If it stops dripping on your table...you are
out of oil.

Put a rag down under the quill if it bothers you. The seals, such as
they are, may be worn, but its a normal thing. Most machine tools of
this vintage are this way.

My big old Gorton MasterMill ****es all over the place and it was
rebuilt not long before I got it. Shrug..nature of the beast. The
only way to slow the drip down, is go to a higher visc oil. Then you
are on your own.

Gunner


Adam Smith wrote:
My model 602 is in exactly the same condition. (1 drip / hour plus or
minus). So I've been all ears lurking on this thread. If you find the
source
for the manual, please mail me or publish it here.

Thanks,

Adam Smith
Midland ON

"Karl Townsend" remove .NOT to reply
wrote
in message k.net...

John,

Cam I email you a pic of my machine? Based on another poster, I may have
the model number wrong. My CNC machine has a Taper 40 spindle, is a bit
larger than a 2J Bridgeport, and has a 2J style head. Sound like yours?
My
machine has a serial no. but can't find a model number on it.

BTW, I need to do the same job. My machine drips oil on the table. Maybe
1
drip per hour, but its a mess after a couple of weeks with no use.
Thanks
for the heads up.

Karl




"John Normile" wrote in message
. net...

Karl
I have a manual for my 602 and it will be no help in determining gear
tooth counts. Just has a cut away view to identify parts. The
machine uses a double reduction gearsets.

Be careful if you disassemble the head. I had mine apart and
replaced all the bearings and seals. When putting it back together
the meshing of the plastic spindle feed gear is critical. If not
meshed with the mating steel gear, guess what happens to the little
$350 gear. The "second time' I used spacers to slowly lower the
castings together while meshing the gears.

Good luck

John Normile



On Sat, 19 Mar 2005 02:39:34 GMT, "Karl Townsend"
remove .NOT to reply wrote:


Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual.
I've
been
lucky and never needed special parts. But, I bet the parts manual
won't
show
enough detail to count teeth. By chance, does anyone know where they
are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways
back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J
style
head.





Every normal man must be tempted, at times, to spit on his hands, hoist
the black flag, and begin slitting throats.
H. L. Mencken

On Fri, 18 Mar 2005 22:17:32 GMT, "Karl Townsend"
remove .NOT to reply wrote:

I need to know the exact gearing ratio for my mill in backgear. This is for
a gear hobbing project I hope to finish within the next X years (X has been
less than one for a couple years now)

Anyway, I have an encoder on my drive spindle that does 4000 counts per
turn. I ran the machine in backgear exactly 100 revolutions and got
2,451,765 pulses. I didn't use an indicator for the begin or end stop point
(mark at end of 4" fly cutter lined up) so the true total could be +/- 250
pulses

This gives a gear ratio of 6.1294. I need a really good guess on the number
of teeth in the drive and driven gear. For example, if the drive gear has 10
teeth and the driven gear has 60 teeth, the ratio would be exactly 6.00.
There's a zillion possibles, I'm looking for one that give a number within a
couple tenths(.0002) of this ratio.

If I have too, I'll tear the machine down. But, I'm hoping there's a math
genious out there. If needed, I could put a counter on the spindle and do
1000 turns.

Someone said it was probably two sets of gears. I wrote a simple
program having 4 gears, with net ratio of a/b * c/d. I ran this for
all combinations of teeth with the following ranges:

a 8 to 100
b 8 to 50
c 8 to 50
d 8 to 100

as a more-or-less arbitrary set of values. I had it save all sets
with total ratio within 0.0001 of 6.1294. There were 24 successes.
The one with the smallest max number of teeth on any gear was:

65, 8, 43 and 57 teeth, ratio of 6.12939.

These are all prime numbers in the sense that they are divisible by no
number less than 8. (I figure 8 is about the minimum number of teeth
on a real gear)

There were two other sets with same ratio:
65, 12,43, 38
65, 24 43, 19

When I did it with a single pair of gears I got no hits even with
tolerance loosened to .001.

On Sun, 20 Mar 2005 18:19:59 -0600, Don Foreman
wrote:

On Fri, 18 Mar 2005 22:17:32 GMT, "Karl Townsend"
remove .NOT to reply wrote:

I need to know the exact gearing ratio for my mill in backgear. This is for
a gear hobbing project I hope to finish within the next X years (X has been
less than one for a couple years now)

Anyway, I have an encoder on my drive spindle that does 4000 counts per
turn. I ran the machine in backgear exactly 100 revolutions and got
2,451,765 pulses. I didn't use an indicator for the begin or end stop point
(mark at end of 4" fly cutter lined up) so the true total could be +/- 250
pulses

This gives a gear ratio of 6.1294. I need a really good guess on the number
of teeth in the drive and driven gear. For example, if the drive gear has 10
teeth and the driven gear has 60 teeth, the ratio would be exactly 6.00.
There's a zillion possibles, I'm looking for one that give a number within a
couple tenths(.0002) of this ratio.

If I have too, I'll tear the machine down. But, I'm hoping there's a math
genious out there. If needed, I could put a counter on the spindle and do
1000 turns.

Someone said it was probably two sets of gears. I wrote a simple
program having 4 gears, with net ratio of a/b * c/d. I ran this for
all combinations of teeth with the following ranges:

a 8 to 100
b 8 to 50
c 8 to 50
d 8 to 100

as a more-or-less arbitrary set of values. I had it save all sets
with total ratio within 0.0001 of 6.1294. There were 24 successes.
The one with the smallest max number of teeth on any gear was:

65, 8, 43 and 57 teeth, ratio of 6.12939.

These are all prime numbers in the sense that they are divisible by no
number less than 8.

Meant to say no number greater than 8 but smaller than the number
itself. A nit, doesn't matter.

In article ,
says...
On Fri, 18 Mar 2005 22:17:32 GMT, "Karl Townsend"
remove .NOT to reply wrote:

I need to know the exact gearing ratio for my mill in backgear. This is for
a gear hobbing project I hope to finish within the next X years (X has been
less than one for a couple years now)

Anyway, I have an encoder on my drive spindle that does 4000 counts per
turn. I ran the machine in backgear exactly 100 revolutions and got
2,451,765 pulses. I didn't use an indicator for the begin or end stop point
(mark at end of 4" fly cutter lined up) so the true total could be +/- 250
pulses

This gives a gear ratio of 6.1294. I need a really good guess on the number
of teeth in the drive and driven gear. For example, if the drive gear has 10
teeth and the driven gear has 60 teeth, the ratio would be exactly 6.00.
There's a zillion possibles, I'm looking for one that give a number within a
couple tenths(.0002) of this ratio.

If I have too, I'll tear the machine down. But, I'm hoping there's a math
genious out there. If needed, I could put a counter on the spindle and do
1000 turns.

Someone said it was probably two sets of gears. I wrote a simple
program having 4 gears, with net ratio of a/b * c/d. I ran this for
all combinations of teeth with the following ranges:

a 8 to 100
b 8 to 50
c 8 to 50
d 8 to 100

as a more-or-less arbitrary set of values. I had it save all sets
with total ratio within 0.0001 of 6.1294. There were 24 successes.
The one with the smallest max number of teeth on any gear was:

65, 8, 43 and 57 teeth, ratio of 6.12939.

These are all prime numbers in the sense that they are divisible by no
number less than 8. (I figure 8 is about the minimum number of teeth
on a real gear)

There were two other sets with same ratio:
65, 12,43, 38
65, 24 43, 19

When I did it with a single pair of gears I got no hits even with
tolerance loosened to .001.



There's one more piece of information you could throw in to
narrow things down. Presumably the input and output of the
gear train are coaxial as on a BP, so if the pitch on both
gear sets is the same

a+b = c+d

If the pitches are different

(a+b)/dp1 = (c+d)/dp2

where dp1 and dp2 are standard diametral pitches in a
reasonable range, say 8,10,12,16,20. An estimate of the
center distance between the two shafts would limit the
range of possibilities further.

Ned Simmons

Ned Simmons

I still get some minor dripping from the quill/housing area, and from
the gearbox for the quill feed. When it gets to be a problem I will
get a cookie sheet and use it to catch the oil.

Excello of Canada will sell you a manual for about $60 (1997 price)

Ex-Cell_O Machine Tools
6015 Center Drive
Sterling Heights MI 48312
810 / 939-1330

Email if I can be of help

John Normile

On Sun, 20 Mar 2005 13:35:07 -0500, "Adam Smith"
wrote:
My model 602 is in exactly the same condition. (1 drip / hour plus or
minus). So I've been all ears lurking on this thread. If you find the source
for the manual, please mail me or publish it here.

Thanks,

Adam Smith
Midland ON

"Karl Townsend" remove .NOT to reply wrote
in message k.net...
John,

Cam I email you a pic of my machine? Based on another poster, I may have
the model number wrong. My CNC machine has a Taper 40 spindle, is a bit
larger than a 2J Bridgeport, and has a 2J style head. Sound like yours? My
machine has a serial no. but can't find a model number on it.

BTW, I need to do the same job. My machine drips oil on the table. Maybe 1
drip per hour, but its a mess after a couple of weeks with no use. Thanks
for the heads up.

Karl




"John Normile" wrote in message
. ..
Karl
I have a manual for my 602 and it will be no help in determining gear
tooth counts. Just has a cut away view to identify parts. The
machine uses a double reduction gearsets.

Be careful if you disassemble the head. I had mine apart and
replaced all the bearings and seals. When putting it back together
the meshing of the plastic spindle feed gear is critical. If not
meshed with the mating steel gear, guess what happens to the little
$350 gear. The "second time' I used spacers to slowly lower the
castings together while meshing the gears.

Good luck

John Normile



On Sat, 19 Mar 2005 02:39:34 GMT, "Karl Townsend"
remove .NOT to reply wrote:

Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual. I've
been
lucky and never needed special parts. But, I bet the parts manual won't
show
enough detail to count teeth. By chance, does anyone know where they are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J style
head.

On Mon, 21 Mar 2005 09:08:33 -0500, Ned Simmons
wrote:


There's one more piece of information you could throw in to
narrow things down. Presumably the input and output of the
gear train are coaxial as on a BP, so if the pitch on both
gear sets is the same

a+b = c+d

If the pitches are different

(a+b)/dp1 = (c+d)/dp2

where dp1 and dp2 are standard diametral pitches in a
reasonable range, say 8,10,12,16,20. An estimate of the
center distance between the two shafts would limit the
range of possibilities further.

Interesting observation, Ned!

Assuming that the ratio for such a speed reduction is somewhat
arbitrary, (so why not 6.25: 1?) and they wouldn't use overly-large
gears if they could help it, I widened the tolerance to .001 and
limited the tooth counts to 50,30, 50, 30, then computed the
difference you mention (a+b -(c+d)) for each set that made the cut.

Results: 39, 20, 44 and 14 give a ratio of 6.128571 with a difference
of 1 tooth in the sums, while 44, 19, 45 and 17 give a ratio of
6.130031 with a difference of 1 tooth.

The best I could do with DP variation was 22,10, 39,14 with DP's of
12 and 20, ratio of 6.128571 -- not

Now, Karl, it's time to count teeth and see what the *real* story is!

Thanks, that is great information.

Adam Smith
Midland ON
"John Normile" wrote in message
.. .
I still get some minor dripping from the quill/housing area, and from
the gearbox for the quill feed. When it gets to be a problem I will
get a cookie sheet and use it to catch the oil.

Excello of Canada will sell you a manual for about $60 (1997 price)

Ex-Cell_O Machine Tools
6015 Center Drive
Sterling Heights MI 48312
810 / 939-1330

Email if I can be of help

John Normile

On Sun, 20 Mar 2005 13:35:07 -0500, "Adam Smith"
wrote:
My model 602 is in exactly the same condition. (1 drip / hour plus or
minus). So I've been all ears lurking on this thread. If you find the
source
for the manual, please mail me or publish it here.

Thanks,

Adam Smith
Midland ON

"Karl Townsend" remove .NOT to reply
wrote
in message k.net...
John,

Cam I email you a pic of my machine? Based on another poster, I may have
the model number wrong. My CNC machine has a Taper 40 spindle, is a bit
larger than a 2J Bridgeport, and has a 2J style head. Sound like yours?
My
machine has a serial no. but can't find a model number on it.

BTW, I need to do the same job. My machine drips oil on the table. Maybe
1
drip per hour, but its a mess after a couple of weeks with no use.
Thanks
for the heads up.

Karl




"John Normile" wrote in message
. ..
Karl
I have a manual for my 602 and it will be no help in determining gear
tooth counts. Just has a cut away view to identify parts. The
machine uses a double reduction gearsets.

Be careful if you disassemble the head. I had mine apart and
replaced all the bearings and seals. When putting it back together
the meshing of the plastic spindle feed gear is critical. If not
meshed with the mating steel gear, guess what happens to the little
$350 gear. The "second time' I used spacers to slowly lower the
castings together while meshing the gears.

Good luck

John Normile



On Sat, 19 Mar 2005 02:39:34 GMT, "Karl Townsend"
remove .NOT to reply wrote:

Karl, can you contact Excello?

Looks like it may be time for me to find them and buy that manual. I've
been
lucky and never needed special parts. But, I bet the parts manual won't
show
enough detail to count teeth. By chance, does anyone know where they
are
located?


Are you positive you have just one set of gears operating here?

I'll guess that its a compound reduction. After all, you don't have to
reverse the motor when you go to back gear, like on the older J head
Bridgeport machine. BTW, I just noticed an error in my post a ways
back.
This machine looks a lot like a Series 1 CNC Bridgeport with a 2J style
head.