gear cutting
 

This question will be a bit hard to answer.
With a smallish lathe (600 mm centre)and a small drill mill which module
cutter set would be the best to to cut the sort of general purpose
gears? not tiny ones for model making.
one instance would be a gearbox to turn a pig on a spit.
maybe the gears on the end of a sheet metal roller or a swage & jenny
machine,or replacement thread turning gears for a lathe.
Module 1 or 1.5 or 2 etc?

gear cutting
 

"F Murtz" wrote in message
ond.com...
This question will be a bit hard to answer.
With a smallish lathe (600 mm centre)and a small drill mill which
module cutter set would be the best to to cut the sort of general
purpose gears? not tiny ones for model making.
one instance would be a gearbox to turn a pig on a spit.
maybe the gears on the end of a sheet metal roller or a swage &
jenny machine,or replacement thread turning gears for a lathe.
Module 1 or 1.5 or 2 etc?

I cut only those gears I can't buy:
https://picasaweb.google.com/KB1DAL/...10360947850418

If you want to cut change gears, you need to match the module of
lathe's existing gears. They would likely be good enough for other
human-powered mechanisms.
http://littlemachineshop.com/product...oduct +Search

jsw

gear cutting
 

Roasting speeds are generally attained by using a worm gear reduction.

--
WB
..........


"F Murtz" wrote in message
ond.com...
This question will be a bit hard to answer.
With a smallish lathe (600 mm centre)and a small drill mill which module
cutter set would be the best to to cut the sort of general purpose gears?
not tiny ones for model making.
one instance would be a gearbox to turn a pig on a spit.
maybe the gears on the end of a sheet metal roller or a swage & jenny
machine,or replacement thread turning gears for a lathe.
Module 1 or 1.5 or 2 etc?

gear cutting
 

On Tue, 10 Apr 2012 14:12:11 -0400, "Wild_Bill"
wrote:

Roasting speeds are generally attained by using a worm gear reduction.

And as long as you're not delivering any serious torque, they're a lot
easier to make.on home-shop machine tools.

I've never made one that big, but I did make a couple of small sets
for my fishing-rod rotisseries, for distributing epoxy around guide
wraps. I cut the gears with ordinary thread taps in my SB 10L lathe,,
and the worm is just a threaded shaft.

--
Ed Huntress

gear cutting
 

Wild_Bill wrote:
Roasting speeds are generally attained by using a worm gear reduction.

Don't you still have to cut a gear? and the worm on a lathe?

gear cutting
 

Jim Wilkins wrote:
"F wrote in message
ond.com...
This question will be a bit hard to answer.
With a smallish lathe (600 mm centre)and a small drill mill which
module cutter set would be the best to to cut the sort of general
purpose gears? not tiny ones for model making.
one instance would be a gearbox to turn a pig on a spit.
maybe the gears on the end of a sheet metal roller or a swage&
jenny machine,or replacement thread turning gears for a lathe.
Module 1 or 1.5 or 2 etc?

I cut only those gears I can't buy:
https://picasaweb.google.com/KB1DAL/...10360947850418

If you want to cut change gears, you need to match the module of
lathe's existing gears. They would likely be good enough for other
human-powered mechanisms.
http://littlemachineshop.com/product...oduct +Search

jsw


How would you work out the module of the set for a change gear in your
hand if you do not have the cutter?

gear cutting
 

On Wed, 11 Apr 2012 10:37:03 +1000, F Murtz
wrote:

Wild_Bill wrote:
Roasting speeds are generally attained by using a worm gear reduction.

Don't you still have to cut a gear? and the worm on a lathe?

A good worm gear is somewhat concave in the middle -- exactly what you
get when you cut it with a tap mounted in the spindle, with the gear
blank freewheeling on some kind of fixture. I have used a lathe, with
the tap in a collet (or maybe in my 4-jaw; it was a long time ago, and
I forget), and the gear blank turning free on a simple spindle held in
my milling attachment. There are other ways to rig it if you don't
have a milling attachment.

The worm is a simple thread-cutting job in the lathe. The set will
match quite well but it's not something you'd want to use for a real
high-torque job.

--
Ed Huntress

gear cutting
 

Ed Huntress fired this volley in
:

The worm is a simple thread-cutting job in the lathe. The set will
match quite well but it's not something you'd want to use for a real
high-torque job.


You could buy a Whitworth or Acme tap, and do a more robust job, still
without "special" tooling.

LLoyd

gear cutting
 

F Murtz fired this volley in news:yp4hr.5616$%
:

I cut only those gears I can't buy:

yep.

"Stock" gears are pretty cheap compared to the tooling and time you have
to spend.

The last set of gears I made was in the mid 1980's, because they had to
be fabric/phenolic, and I couldn't find a set anywhere made of them.

It's a lot more efficient in time AND cost to adjust your design (if you
can) to fit off-the-shelf gears and worms.

LLoyd

gear cutting
 

"F Murtz" wrote in message
ond.com...
...

How would you work out the module of the set for a change gear in
your hand if you do not have the cutter?

It's all in he
http://www.amazon.com/Gears-Cutting-.../dp/0852429118

You measure the outside diameter and count the teeth.

Determining the pressure angle is harder. 20 degrees is a common
standard for power transmission, the older 14.5 degree PA has hung on
for some lathe change gears. I use the drawings in catalogs to
identify it.

jsw

gear cutting
 

On Tue, 10 Apr 2012 20:01:27 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Ed Huntress fired this volley in
:

The worm is a simple thread-cutting job in the lathe. The set will
match quite well but it's not something you'd want to use for a real
high-torque job.


You could buy a Whitworth or Acme tap, and do a more robust job, still
without "special" tooling.

LLoyd

In fact, my last one was made with a long-shank 1/2" Acme tap, which
is better and probably stronger, but I didn't want to make it sound
complicated. You can do a credible job for a low-torque application,
like a rotisserie (unless you're roasting whole pigs) with a regular
tap.

I made one that way around 30 years ago that still drives my
fishing-rod rotisserie. The one I made with the Acme tap was supposed
to replace it, but the original worked fine so I gave the newer set to
another rod-builder friend.

--
Ed Huntress

gear cutting
 

On 10-Apr-2012 11:01, F Murtz wrote:
a gearbox to turn a pig on a spit.


I made a spit to turn a whole lamb. I used mild steel rod and turn it
using a 12V worm-geared window winder motor further geared down using
ANSI 35 chain, weld-on sprockets and hubs to fit the shafts. Works
great and runs for hours on a 12V utility battery.

__________________________________________________ __________________
Gardner Buchanan gbuchana(a)teksavvy(dot)com
FreeBSD: Where you want to go. Today.

gear cutting
 

On 2012-04-10, F Murtz wrote:
This question will be a bit hard to answer.
With a smallish lathe (600 mm centre)and a small drill mill which module

Is that "center height", or "between centers"? It makes a big
difference in the size of the lathe. :-)

cutter set would be the best to to cut the sort of general purpose
gears? not tiny ones for model making.
one instance would be a gearbox to turn a pig on a spit.
maybe the gears on the end of a sheet metal roller or a swage & jenny
machine,or replacement thread turning gears for a lathe.
Module 1 or 1.5 or 2 etc?

Well ... I'm not really familiar with the module gears, but in
Imperial ones, for the first task (the pig on a spit) I would probably
of with something like 32 DP (Diametrical Pitch). (I've made such gears
for repairing a piece of electronic test equipment.)

For the lathe threading gears, it really depends on the size of
the lathe. Presumably, since you say "replacement gears", you should
duplicate what the manufacturer used originally -- so the new ones would
mesh with the old ones. FWIW, My Clausing (12" swing or 6" center
height) (that would be about 300 mm swing, or 150 mm center height) is
not small by hobby standards, though certainly so by industrial
standards, and it uses 20 DP (Diametrical Pitch).

By consulting a book like _Machinery's Handbook_, you can
convert one system into an approximate size for at tooth thickness (not
width) at the pitch diameter, convert that into the other system, and
find what is the closest standard size in the new system.

At present, I have no real motivation to make metric (module)
gears, because the gear cutter sets are much harder to find (at least
here in the USA) than those for the imperial gears -- and nothing which I
have needed to repair has yet needed Module gears.

FWIW -- I have a full set of the 20 DP cutters (for my lathe's
gears), and only one of the 32 DP ones, as I only needed to make one
size of gear.

Good Luck,
DoN.

--
Remove oil spill source from e-mail
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

gear cutting
 

On 4/11/2012 8:15 PM, Gardner wrote:
On 10-Apr-2012 11:01, F Murtz wrote:
a gearbox to turn a pig on a spit.


I made a spit to turn a whole lamb. I used mild steel rod and turn it
using a 12V worm-geared window winder motor further geared down using
ANSI 35 chain, weld-on sprockets and hubs to fit the shafts. Works
great and runs for hours on a 12V utility battery.

__________________________________________________ __________________
Gardner Buchanan gbuchana(a)teksavvy(dot)com
FreeBSD: Where you want to go. Today.


HEY NOW! That might be a relative!

gear cutting
 

DoN. Nichols wrote:
On 2012-04-10, F wrote:
This question will be a bit hard to answer.
With a smallish lathe (600 mm centre)and a small drill mill which module

Is that "center height", or "between centers"? It makes a big
difference in the size of the lathe. :-)

cutter set would be the best to to cut the sort of general purpose
gears? not tiny ones for model making.
one instance would be a gearbox to turn a pig on a spit.
maybe the gears on the end of a sheet metal roller or a swage& jenny
machine,or replacement thread turning gears for a lathe.
Module 1 or 1.5 or 2 etc?

Well ... I'm not really familiar with the module gears, but in
Imperial ones, for the first task (the pig on a spit) I would probably
of with something like 32 DP (Diametrical Pitch). (I've made such gears
for repairing a piece of electronic test equipment.)

For the lathe threading gears, it really depends on the size of
the lathe. Presumably, since you say "replacement gears", you should
duplicate what the manufacturer used originally -- so the new ones would
mesh with the old ones. FWIW, My Clausing (12" swing or 6" center
height) (that would be about 300 mm swing, or 150 mm center height) is
not small by hobby standards, though certainly so by industrial
standards, and it uses 20 DP (Diametrical Pitch).

By consulting a book like _Machinery's Handbook_, you can
convert one system into an approximate size for at tooth thickness (not
width) at the pitch diameter, convert that into the other system, and
find what is the closest standard size in the new system.

At present, I have no real motivation to make metric (module)
gears, because the gear cutter sets are much harder to find (at least
here in the USA) than those for the imperial gears -- and nothing which I
have needed to repair has yet needed Module gears.

FWIW -- I have a full set of the 20 DP cutters (for my lathe's
gears), and only one of the 32 DP ones, as I only needed to make one
size of gear.

Good Luck,
DoN.



the lathe is 600 mm between centres 320 mm swing (160 mm high)38 mm
spindle bore.
My question was not so much that I need any of the things that I
mentioned, just an indication of the size that I may want in the future,
I was just thinking of getting a set of cutters so that if I got a bee
in my bonnet in the middle of the night I could set to making something
and I was just trying to get an idea of which set of cutters would be
the most useful to have on hand.If I had a special job which would
require matching I would probably have to get cutters specially.
If you were making the whole set of gears you are not restricted to matching

gear cutting
 

Richard wrote:

Gardner wrote:
F Murtz wrote:
a gearbox to turn a pig on a spit.

I made a spit to turn a whole lamb. I used mild steel rod and turn it
using a 12V worm-geared window winder motor further geared down using
ANSI 35 chain, weld-on sprockets and hubs to fit the shafts. Works
great and runs for hours on a 12V utility battery.

HEY NOW! That might be a relative!


More likely, 'The black sheep of the family'. ;-)


--
You can't have a sense of humor, if you have no sense.

gear cutting
 

On 2012-04-12, F Murtz wrote:
DoN. Nichols wrote:
On 2012-04-10, F wrote:
This question will be a bit hard to answer.
With a smallish lathe (600 mm centre)and a small drill mill which module

Is that "center height", or "between centers"? It makes a big
difference in the size of the lathe. :-)

cutter set would be the best to to cut the sort of general purpose
gears? not tiny ones for model making.
one instance would be a gearbox to turn a pig on a spit.
maybe the gears on the end of a sheet metal roller or a swage& jenny
machine,or replacement thread turning gears for a lathe.
Module 1 or 1.5 or 2 etc?

Well ... I'm not really familiar with the module gears, but in
Imperial ones, for the first task (the pig on a spit) I would probably
of with something like 32 DP (Diametrical Pitch). (I've made such gears
for repairing a piece of electronic test equipment.)

[ ... ]

By consulting a book like _Machinery's Handbook_, you can
convert one system into an approximate size for at tooth thickness (not
width) at the pitch diameter, convert that into the other system, and
find what is the closest standard size in the new system.

[ ... ]

FWIW -- I have a full set of the 20 DP cutters (for my lathe's
gears), and only one of the 32 DP ones, as I only needed to make one
size of gear.

the lathe is 600 mm between centres 320 mm swing (160 mm high)38 mm
spindle bore.

O.K. Then for that size, (a bit over 6" swing), I would
probably go somewhere closer to the 32 DP (again in Imperial than the 20
DP. Perhaps 24 or 28 DP (I should to look it up to make sure that
those are standard sizes, but they could be, and would be pretty good
choices for that size lathe. :-)

If my guesses about the size ratios is right, 32 DP would be
about module 0.80 , and 24 DP would be around module 1.0. So I would
say that your module 1.0 would probably be a good choice for most
things in your size range.

My question was not so much that I need any of the things that I
mentioned, just an indication of the size that I may want in the future,
I was just thinking of getting a set of cutters so that if I got a bee
in my bonnet in the middle of the night I could set to making something
and I was just trying to get an idea of which set of cutters would be
the most useful to have on hand.

O.K. Do you have an index head for dividing the gear? Three
dividing plates and a 40:1 ratio are what I am familiar with. It *can*
be done with a rotary table, but without dividing plates and sector
arms, it is rather error prone.

If I had a special job which would
require matching I would probably have to get cutters specially.
If you were making the whole set of gears you are not restricted to matching

Understood. When you mentioned change gears for a lathe, I was
thinking in terms of replacing a few missing ones.

FWIW While I got a full set of 20 DP gear cutters to match my lathe,
the first gear that I actually *cut* required ordering a
separate cutter -- different DP, and different pressure angle
(PA) as well. :-)

Good Luck,
DoN.

--
Remove oil spill source from e-mail
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---