Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work.

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Default Dividing head

I was going to make a quick and dirty dividing head to use with my
Taig chucks on my X2 mill.

I thought I would basically run a shaft through a block of aluminum
with 3/4-16 thread on one end and a dividing plate on the other. Then
I thought: What shaft? What bearings?

Primary concerns here are not the rotation loads but absence of radial
and axial movement of the shaft.

I am not sure what engineering principles apply. Would an aluminum
shaft with a slip fit through a hole in the aluminum block suffice?
Presumably a steel shaft would wear out the aluminum. Would it be
better to use a steel shaft with bronze bushings? Ball-bearings seem a
bit of an overkill.

Maybe by the time I think this through I will find it expedient to get
a Taig headstock for $60+ and use it as a base for the project (a
common approach, apparently). However, I would still like to know what
is the correct approach if building from scratch.

Thanks,

Michael Koblic,
Campbell River, BC
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Default Dividing head

On Mar 9, 3:47*am, wrote:
I was going to make a quick and dirty dividing head to use with my
Taig chucks on my X2 mill.

I thought I would basically run a shaft through a block of aluminum
with 3/4-16 thread on one end and a dividing plate on the other. Then
I thought: What shaft? What bearings?

Primary concerns here are not the rotation loads but absence of radial
and axial movement of the shaft.

I am not sure what engineering principles apply. Would an aluminum
shaft with a slip fit through a hole in the aluminum block suffice?
Presumably a steel shaft would wear out the aluminum. Would it be
better to use a steel shaft with bronze bushings? Ball-bearings seem a
bit of an overkill.

Maybe by the time I think this through I will find it expedient to get
a Taig headstock for $60+ and use it as a base for the project (a
common approach, apparently). However, I would still like to know what
is the correct approach if building from scratch.

Thanks,

Michael Koblic,
Campbell River, BC


I like these:
http://www.kalamazooind.com/products...exing-fixture/
I bought two used ones for ~$50 each and mounted one on an angle plate
with the axis vertical. If necessary the second can serve as a
tailstock to steady a long shaft, like the splined pulley broach I
have to make soon.

The Spin Indexer is less rigid but can be set to 1 degree with the
vernier holes on the top:
http://www.phase2plus.com/details.as...IN_INDEX&id=58

A chuck for them:
http://www.tools4cheap.net/proddetail.php?prod=5c3jaw

Then there's this:
http://www.harborfreight.com/3-inch-...kit-98077.html

The rotation load is VERY important when milling if the work diameter
is larger than the shaft clamp. You can arrange a clamp that secures
the work directly to the mill table at the cost of inconvenience.

jsw
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Default Dividing head

On Mar 9, 1:47*am, wrote:
I was going to make a quick and dirty dividing head to use with my
Taig chucks on my X2 mill.

I thought I would basically run a shaft through a block of aluminum
with 3/4-16 thread on one end and a dividing plate on the other. Then
I thought: What shaft? What bearings?

Primary concerns here are not the rotation loads but absence of radial
and axial movement of the shaft.

I am not sure what engineering principles apply. Would an aluminum
shaft with a slip fit through a hole in the aluminum block suffice?
Presumably a steel shaft would wear out the aluminum. Would it be
better to use a steel shaft with bronze bushings? Ball-bearings seem a
bit of an overkill.

Maybe by the time I think this through I will find it expedient to get
a Taig headstock for $60+ and use it as a base for the project (a
common approach, apparently). However, I would still like to know what
is the correct approach if building from scratch.

Thanks,

Michael Koblic,
Campbell River, BC


Current Home Shop Machinist has a how-to for a cheapie indexer using
change wheels on an Atlas 6". I've seen similar using just a block of
scrapbox steel and a shaft with suitable arrangements for attaching
the gears. No bearings used besides a good running fit. A spring-
loaded plunger to fit the gaps in the teeth does the indexing.
Probably an afternoon's project. Or you can just get a 5C indexing
block set and have at it.

Stan
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Default Dividing head

On 2011-03-09, wrote:
I was going to make a quick and dirty dividing head to use with my
Taig chucks on my X2 mill.

I thought I would basically run a shaft through a block of aluminum
with 3/4-16 thread on one end and a dividing plate on the other. Then
I thought: What shaft? What bearings?

Primary concerns here are not the rotation loads but absence of radial
and axial movement of the shaft.

I am not sure what engineering principles apply. Would an aluminum
shaft with a slip fit through a hole in the aluminum block suffice?


Likely to suffer galling.

Presumably a steel shaft would wear out the aluminum.


Actually -- a polished steel shaft would be a better bearing
with the aluminum housing than an al-al interface. keep it lubed, of
course.

Would it be
better to use a steel shaft with bronze bushings? Ball-bearings seem a
bit of an overkill.


How much load forces are you expecting?

Maybe by the time I think this through I will find it expedient to get
a Taig headstock for $60+ and use it as a base for the project (a
common approach, apparently). However, I would still like to know what
is the correct approach if building from scratch.


Or -- perhaps get an old Unimat or Emco-Maier dividing head, if
you need no more than 60 divisions.

Of course -- the Unimat ones go for crazy money these days, if
you can find them on eBay at all. People are *collecting* these things
instead of using them. :-)

Enjoy,
DoN.

--
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Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. |
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Default Dividing head

On Wed, 9 Mar 2011 04:59:33 -0800 (PST), Jim Wilkins
wrote:

On Mar 9, 3:47*am, wrote:
I was going to make a quick and dirty dividing head to use with my
Taig chucks on my X2 mill.

I thought I would basically run a shaft through a block of aluminum
with 3/4-16 thread on one end and a dividing plate on the other. Then
I thought: What shaft? What bearings?

Primary concerns here are not the rotation loads but absence of radial
and axial movement of the shaft.

I am not sure what engineering principles apply. Would an aluminum
shaft with a slip fit through a hole in the aluminum block suffice?
Presumably a steel shaft would wear out the aluminum. Would it be
better to use a steel shaft with bronze bushings? Ball-bearings seem a
bit of an overkill.

Maybe by the time I think this through I will find it expedient to get
a Taig headstock for $60+ and use it as a base for the project (a
common approach, apparently). However, I would still like to know what
is the correct approach if building from scratch.

Thanks,

Michael Koblic,
Campbell River, BC


I like these:
http://www.kalamazooind.com/products...exing-fixture/
I bought two used ones for ~$50 each and mounted one on an angle plate
with the axis vertical. If necessary the second can serve as a
tailstock to steady a long shaft, like the splined pulley broach I
have to make soon.

The Spin Indexer is less rigid but can be set to 1 degree with the
vernier holes on the top:
http://www.phase2plus.com/details.as...IN_INDEX&id=58

A chuck for them:
http://www.tools4cheap.net/proddetail.php?prod=5c3jaw

Then there's this:
http://www.harborfreight.com/3-inch-...kit-98077.html

The rotation load is VERY important when milling if the work diameter
is larger than the shaft clamp. You can arrange a clamp that secures
the work directly to the mill table at the cost of inconvenience.

jsw


I have looked at all of those at one time or another. I rejected the
spin indexer because of the 5C collets. The chuck adds $100 to the
cost. The rotary tables have the same problem.

Right now the job is to drill several cross holes in round stock at
precise but not necessarily outlandish angles. I was also trying to
use what was in the drawer. Maybe even learn how to thread on a lathe
:-)

I was going to buy the Grizzly rapid indexer but both Grizzly and Busy
Bee are out of stock. Also at 6" it would probably bee a tad too big
for my X2.

I suppose an option would be a spin indexer, a 3/4" collet holding a
short shaft with 3/4"-16 thread and a Taig chuck. Now that you made me
look at things again I should consider it.

Michael Koblic,
Campbell River, BC


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Default Dividing head

On 10 Mar 2011 01:13:51 GMT, "DoN. Nichols"
wrote:

[...]


I am not sure what engineering principles apply. Would an aluminum
shaft with a slip fit through a hole in the aluminum block suffice?


Likely to suffer galling.

Presumably a steel shaft would wear out the aluminum.


Actually -- a polished steel shaft would be a better bearing
with the aluminum housing than an al-al interface. keep it lubed, of
course.


OK, thanks, I don't have a clue about this stuff.

Would it be
better to use a steel shaft with bronze bushings? Ball-bearings seem a
bit of an overkill.


How much load forces are you expecting?


Drilling cross holes type of forces. However, if one could make it
more versatile by simple means, why not?

Maybe by the time I think this through I will find it expedient to get
a Taig headstock for $60+ and use it as a base for the project (a
common approach, apparently). However, I would still like to know what
is the correct approach if building from scratch.


Or -- perhaps get an old Unimat or Emco-Maier dividing head, if
you need no more than 60 divisions.

Of course -- the Unimat ones go for crazy money these days, if
you can find them on eBay at all. People are *collecting* these things
instead of using them. :-)

I saw a really neat little rotary table in the Proxxon catalog. It had
an integral chuck. I have not been able to find a dealer for it so
far.

But given the principles you outlined I might be able to knock
something together.

Michael Koblic,
Campbell River, BC
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Default Dividing head


"DoN. Nichols" wrote in message
...


People are *collecting* these things instead of using them. :-)


To quote:

Warren Buffett


The line separating investment and speculation, which is never bright and
clear, becomes blurred still further when most market participants have
recently enjoyed triumphs. Nothing sedates rationality like large doses of
effortless money. After a heady experience of that kind, normally sensible
people drift into behavior akin to that of Cinderella at the ball. They know
that overstaying the festivities -- that is, continuing to speculate in
companies that have gigantic valuations relative to the cash they are likely
to generate in the future -- will eventually bring on pumpkins and mice. But
they nevertheless hate to miss a single minute of what is one helluva party.
Therefore, the giddy participants all plan to leave just seconds before
midnight. There's a problem, though: They are dancing in a room in which the
clocks have no hands.
a.. Berkshire Hathaway 2000 Chairman's Letter


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On Mar 10, 11:58*am, wolfgang wrote:
...
I do most cross drilling of round parts in the lathe with a motorized
drill spindle that fits the QCTP at lathe centre line height.

The spindle is aligned parallel to the chuck face with a 123 block and
is driven by a windshield wiper motor at 30VDC or so, developing about
1/4 HP....
Wolfgang-


Similarly I made a Dremel tool holder from an upright rectangle of
aluminum plate thicker than the compound slot.

The lower edge was stepped to fit snugly into the slot. A vertical
hole near the right edge takes the hold-down made from a carriage
bolt.

I set the compound parallel to the ways and bored a snug hole at
center height for the Dremel nose. If the hole had been a looser fit I
could have slotted the block to let the carriage bolt clamp the
Dremel. The compound feed screw runs a drill bit straight in or a
grinding wheel at the compound's angle.

My next project of that type is to adapt a laminate trimmer to the
larger lathe.

jsw
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Default Dividing head

On Thu, 10 Mar 2011 13:31:44 -0800 (PST), Jim Wilkins
wrote:

On Mar 10, 11:58*am, wolfgang wrote:
...
I do most cross drilling of round parts in the lathe with a motorized
drill spindle that fits the QCTP at lathe centre line height.

The spindle is aligned parallel to the chuck face with a 123 block and
is driven by a windshield wiper motor at 30VDC or so, developing about
1/4 HP....
Wolfgang-


Similarly I made a Dremel tool holder from an upright rectangle of
aluminum plate thicker than the compound slot.

The lower edge was stepped to fit snugly into the slot. A vertical
hole near the right edge takes the hold-down made from a carriage
bolt.

I set the compound parallel to the ways and bored a snug hole at
center height for the Dremel nose. If the hole had been a looser fit I
could have slotted the block to let the carriage bolt clamp the
Dremel. The compound feed screw runs a drill bit straight in or a
grinding wheel at the compound's angle.

My next project of that type is to adapt a laminate trimmer to the
larger lathe.


I have been looking at the similar arrangement and have not ruled it
out completely:

1) Do it on the Taig. Make a divider plate which should be relatively
simple and the spindle lock is easier to make than on the 9x20. Adapt
one of the toolholders (or make a brand new one) for the Dremel flex
shaft. The only thing that put me off that is the 1/8" or so limit of
the Dremel. In fact the whole concept started me thinking along the
lines of buying a new Taig headstock and adapting it as a dividing
head - then I could also mill etc. on the X2.

2) Do it on the 9x20. It should not be difficult to make a clamp for
the Dremel flex shaft here either. The cons are no spindle lock and
the drill size limit as above. I am not sure that I grasp the concept
of the "spacer pin". However, if I found a way to lock the spindle in
any position one could use a magnetic protractor gauge which I have
found eminently useful in other applications to set the angles.

3) Do it on the *wood lathe* - that one has not only a spindle lock
but an in-built dividing plate with 72 positions. Again the Dremel
holder should be easy to adapt to the tool rest banjo, but the above
limitations apply. Also would have to get a new chuck for the 1"-8
spindle. OTOH how easy would it be to get one of those MT2/plain
adaptors and cut 3/4"-16 thread on it and use it with the Taig
chucks?


BTW I have been looking around at the spin indexers: Somebody on
another forum posted pictures of the indexer which he adapted for ER40
collets! I thought it was a particularly smart move but could not find
a description of how he did it.

Many options could result in paralysis by analysis :-) However, as the
job is not imminent, it is good to explore them.

Michael Koblic,
Campbell River, BC

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On Mar 11, 2:12*am, wrote:
On Thu, 10 Mar 2011 13:31:44 -0800 (PST), Jim Wilkins
...
1) Do it on the Taig. Make a divider plate which should be relatively
simple and the spindle lock is easier to make than on the 9x20. Adapt
one of the toolholders (or make a brand new one) for the Dremel flex
shaft. The only thing that put me off that is the 1/8" or so limit of
the Dremel. In fact the whole concept started me thinking along the
lines of buying a new Taig headstock and adapting it as a dividing
head - then I could also mill etc. on the X2.


Instead of locking the spindle you can clamp the divider plate. The
leverage would be better.
The laminate trimmer has 1/4" collets and better mounting surfaces
than a die grinder.
Speed control:
http://www.amptone.com/images/tenmavariac.jpg

3) Do it on the *wood lathe* - that one has not only a spindle lock
but an in-built dividing plate with 72 positions. Again the Dremel
holder should be easy to adapt to the tool rest banjo, but the above
limitations apply. Also would have to get a new chuck for the 1"-8
spindle. OTOH how easy would it be to get one of those MT2/plain
adaptors and cut *3/4"-16 thread on it and use it with the Taig
chucks?


Buy one of these, tighten a nut on it and thread the nut:
http://stores.homestead.com/WaldenSpecialties/-strse-31/MT2-Threaded-Arbor,-1-fdsh-2''/Detail.bok
I'd face the arbor flange side of the nut first and saw a slot so it
could be removed if it stays in the chuck. Or leave a hex flange on
the nut.

BTW I have been looking around at the spin indexers: Somebody on
another forum posted pictures of the indexer which he adapted for ER40
collets! I thought it was a particularly smart move but could not find
a description of how he did it.
Michael Koblic,


Why bother unless you already have the ER collets? 5C collets are as
cheap as any other and are the standard for square and hex collet
blocks, end mill grinding fixtures etc.
http://www.micro-machine-shop.com/Co...tm#5C_fixtures
Those are fine for cross-drilling a shaft or milling a square or hex
head.

You could pick a few appropriate sizes for your rod stock and collets,
you don't need a full set. I chose 1/2" and 1" for expensive metal
like O-1, 12L14, 303, 4142 etc.

jsw


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Default Dividing head

On Mar 11, 2:12*am, wrote:
On Thu, 10 Mar 2011 13:31:44 -0800 (PST), Jim Wilkins



wrote:
On Mar 10, 11:58 am, wolfgang wrote:
...
I do most cross drilling of round parts in the lathe with a motorized
drill spindle that fits the QCTP at lathe centre line height.


The spindle is aligned parallel to the chuck face with a 123 block and
is driven by a windshield wiper motor at 30VDC or so, developing about
1/4 HP....
Wolfgang-


Similarly I made a Dremel tool holder from an upright rectangle of
aluminum plate thicker than the compound slot.


The lower edge was stepped to fit snugly into the slot. A vertical
hole near the right edge takes the hold-down made from a carriage
bolt.


I set the compound parallel to the ways and bored a snug hole at
center height for the Dremel nose. If the hole had been a looser fit I
could have slotted the block to let the carriage bolt clamp the
Dremel. The compound feed screw runs a drill bit straight in or a
grinding wheel at the compound's angle.


My next project of that type is to adapt a laminate trimmer to the
larger lathe.


I have been looking at the similar arrangement and have not ruled it
out completely:

1) Do it on the Taig. Make a divider plate which should be relatively
simple and the spindle lock is easier to make than on the 9x20. Adapt
one of the toolholders (or make a brand new one) for the Dremel flex
shaft. The only thing that put me off that is the 1/8" or so limit of
the Dremel. In fact the whole concept started me thinking along the
lines of buying a new Taig headstock and adapting it as a dividing
head - then I could also mill etc. on the X2.

2) Do it on the 9x20. It should not be difficult to make a clamp for
the Dremel flex shaft here either. The cons are no spindle lock and
the drill size limit as above. I am not sure that I grasp the concept
of the "spacer pin". However, if I found a way to lock the spindle in
any position one could use a magnetic protractor gauge which I have
found eminently useful in other applications to set the angles.

3) Do it on the *wood lathe* - that one has not only a spindle lock
but an in-built dividing plate with 72 positions. Again the Dremel
holder should be easy to adapt to the tool rest banjo, but the above
limitations apply. Also would have to get a new chuck for the 1"-8
spindle. OTOH how easy would it be to get one of those MT2/plain
adaptors and cut *3/4"-16 thread on it and use it with the Taig
chucks?

BTW I have been looking around at the spin indexers: Somebody on
another forum posted pictures of the indexer which he adapted for ER40
collets! I thought it was a particularly smart move but could not find
a description of how he did it.

Many options could result in paralysis by analysis :-) However, as the
job is not imminent, it is good to explore them.

Michael Koblic,
Campbell River, BC




Mike,

Today there are more options than there were when I built my tooling.
I found the dremel tool speed too high for effective drilling of
steel.

The spacer pin (or bar) is a length of rod that I place between the
bottom edge of the horizontal chuck jaw and the flat of the lathe
bed; this makes for quick-and-dirty indexing. By careful choice of
this spacer you can get 6 divisions quickly depending on your lathe's
design. Certainly 3 div's are easy and a cross hole is a cinch.

Cross drilling does not impose a rotational force on the work piece
and I found that clamping of the lathe spindle, for this operation, is
not necessary. If you are concerned simply hold the spindle, by hand,
against the spacer pin mentioned above.

My drilling spindle runs on 2 ball bearings of 3/8" bore and mounts a
threaded 1/4" capacity drill chuck. It is driven by a windshield
wiper motor through a 3-1 reduction timing belt.

Built into the lathe bench is a variable AC and DC power supply
controlled by a Variac auto transformer. This is a permanent set-up
as I use this for other work and experiments. The variable AC is fed
into a step-down transformer, rectified and smoothed with big
capacitors. This transformer can handle up to 40 Amps or so and can
supply up to 30 volts DC. Most wiper motors are very robust and
reliable and can handle this easily. In the last decade or so really
powerful radiator fan motors have become available and I would use one
of these if I were to do this again.

Once you have this device you will be amazed how easily you can carry
out what is otherwise a tedious operation.

For a small lathe a flexible shaft driven hand piece held in a
dedicated QCTH would be the way to go. Take the time to make a nice
tool that will provide use and enjoyment for a life time.

As a guide to the tool holder simply look at the commercial
toolholders that carry a fixed drill chuck. Extend the back side of
this holder by some measure and drill & bore it to take 2 ball
bearings or the hand piece, where the drill chuck is mounted.

By planning ahead this tool can be used for cross and axial offset
drilling ie holes in a bolt circle. For this though a lathe spindle
clamp is advisable.

Wolfgang

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On Fri, 11 Mar 2011 06:40:48 -0800 (PST), Jim Wilkins
wrote:

[...]

Instead of locking the spindle you can clamp the divider plate. The
leverage would be better.


Actually that is the way I was planning to do it. A pin through one of
the holes on the plate.

The laminate trimmer has 1/4" collets and better mounting surfaces
than a die grinder.
Speed control:
http://www.amptone.com/images/tenmavariac.jpg


What are you going to use it for?


3) Do it on the *wood lathe* - that one has not only a spindle lock
but an in-built dividing plate with 72 positions. Again the Dremel
holder should be easy to adapt to the tool rest banjo, but the above
limitations apply. Also would have to get a new chuck for the 1"-8
spindle. OTOH how easy would it be to get one of those MT2/plain
adaptors and cut *3/4"-16 thread on it and use it with the Taig
chucks?


Buy one of these, tighten a nut on it and thread the nut:
http://stores.homestead.com/WaldenSpecialties/-strse-31/MT2-Threaded-Arbor,-1-fdsh-2''/Detail.bok
I'd face the arbor flange side of the nut first and saw a slot so it
could be removed if it stays in the chuck. Or leave a hex flange on
the nut.


OK. Is an adaptor with an internal thread 1"-8 (for the lathe spindle)
and 3/4" -16 outside thread (for the chuck0 an option? I was
wondering how to preserve the through hole.

BTW I have been looking around at the spin indexers: Somebody on
another forum posted pictures of the indexer which he adapted for ER40
collets! I thought it was a particularly smart move but could not find
a description of how he did it.
Michael Koblic,


Why bother unless you already have the ER collets? 5C collets are as
cheap as any other and are the standard for square and hex collet
blocks, end mill grinding fixtures etc


The benefit is the extended range of grip. Much of the stuff I use is
not within the 0.003" or so of the 5C collet size.

http://www.micro-machine-shop.com/Co...tm#5C_fixtures
Those are fine for cross-drilling a shaft or milling a square or hex
head.


The 10th picture down. From what I read people use these blocks more
than anything else. I even thought of them and a single 3/4" 5C collet
with a threaded shaft through it to match the Taig chucks.

Picture No. 21 is probably one of the cheaper combinations I have
looked at: Spin indexer and a 5C chuck. My concern there was that I
would run out of space on the X2 table.

You could pick a few appropriate sizes for your rod stock and collets,
you don't need a full set. I chose 1/2" and 1" for expensive metal
like O-1, 12L14, 303, 4142 etc.


I shall re-consider it.

Michael Koblic,
Campbell River, BC
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On Fri, 11 Mar 2011 09:08:59 -0800 (PST), wolfgang
wrote:

[...]

Today there are more options than there were when I built my tooling.
I found the dremel tool speed too high for effective drilling of
steel.


Agreed. Even 1/8" is pushing it with 5000 rpm.

The spacer pin (or bar) is a length of rod that I place between the
bottom edge of the horizontal chuck jaw and the flat of the lathe
bed; this makes for quick-and-dirty indexing. By careful choice of
this spacer you can get 6 divisions quickly depending on your lathe's
design. Certainly 3 div's are easy and a cross hole is a cinch.

Cross drilling does not impose a rotational force on the work piece
and I found that clamping of the lathe spindle, for this operation, is
not necessary. If you are concerned simply hold the spindle, by hand,
against the spacer pin mentioned above.


I need to visualize this. There is a hole directly under the chuck on
my lathe. I guess some kind of a wooden block etc. might do.

I was thinking of making a big handle for my 9x20 and attach it to the
other side of the spindle. I thought it would help with threading
amongst other things. I should be able to think of ways to immobilize
the handle in various positions.

My drilling spindle runs on 2 ball bearings of 3/8" bore and mounts a
threaded 1/4" capacity drill chuck. It is driven by a windshield
wiper motor through a 3-1 reduction timing belt.

Built into the lathe bench is a variable AC and DC power supply
controlled by a Variac auto transformer. This is a permanent set-up
as I use this for other work and experiments. The variable AC is fed
into a step-down transformer, rectified and smoothed with big
capacitors. This transformer can handle up to 40 Amps or so and can
supply up to 30 volts DC. Most wiper motors are very robust and
reliable and can handle this easily. In the last decade or so really
powerful radiator fan motors have become available and I would use one
of these if I were to do this again.

Once you have this device you will be amazed how easily you can carry
out what is otherwise a tedious operation.

For a small lathe a flexible shaft driven hand piece held in a
dedicated QCTH would be the way to go. Take the time to make a nice
tool that will provide use and enjoyment for a life time.

As a guide to the tool holder simply look at the commercial
toolholders that carry a fixed drill chuck. Extend the back side of
this holder by some measure and drill & bore it to take 2 ball
bearings or the hand piece, where the drill chuck is mounted.

By planning ahead this tool can be used for cross and axial offset
drilling ie holes in a bolt circle. For this though a lathe spindle
clamp is advisable.

Those are certainly considerations, thanks.

Michael Koblic,
Campbell River, BC
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Default Dividing head

I don't mind dividing head but I always get the first round and then the
rest of you guys can have her after that.

------------------

wrote in message ...

I was going to make a quick and dirty dividing head to use with my
Taig chucks on my X2 mill.

I thought I would basically run a shaft through a block of aluminum
with 3/4-16 thread on one end and a dividing plate on the other. Then
I thought: What shaft? What bearings?

Primary concerns here are not the rotation loads but absence of radial
and axial movement of the shaft.

I am not sure what engineering principles apply. Would an aluminum
shaft with a slip fit through a hole in the aluminum block suffice?
Presumably a steel shaft would wear out the aluminum. Would it be
better to use a steel shaft with bronze bushings? Ball-bearings seem a
bit of an overkill.

Maybe by the time I think this through I will find it expedient to get
a Taig headstock for $60+ and use it as a base for the project (a
common approach, apparently). However, I would still like to know what
is the correct approach if building from scratch.

Thanks,

Michael Koblic,
Campbell River, BC

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On Mar 11, 7:13*pm, wrote:
On Fri, 11 Mar 2011 06:40:48 -0800 (PST), Jim Wilkins


The laminate trimmer has 1/4" collets and better mounting surfaces
than a die grinder.


What are you going to use it for?


A bigger Dremel that takes 1/4" shank carbide burrs. Though so far
I've confined all grinding to the smaller, less valuable AA lathe,
which has a 1/2" - 20 drill chuck on its spindle. They are safer (I
think) to file and sand near than a 3 or 4 jaw chuck. I recently
ground 1/8" music wire into a router bit to deepen the O-ring groove
on a hydraulic pump.

OK. Is an adaptor with an internal thread 1"-8 (for the lathe spindle)
and 3/4" -16 outside thread *(for the chuck) an option? I was
wondering how to preserve the through hole.


I'd sooner make a new backplate. Several attempts at mounting a 1-1/2"
- 8 threaded Jacobs 58B chuck to my 2-1/4" - 8 spindle haven't been
all I could ask for. Maybe the chuck itself isn't rigid enough to turn
a good finish.
http://media.photobucket.com/image/J.../jakechuck.jpg
However it fits nicely on an Enco version of these:
http://grizzly.com/products/G1053

Some discussion:
http://www.armurerieduroi.com/pages/...ck_jacobs.html

BTW I have been looking around at the spin indexers: Somebody on
another forum posted pictures of the indexer which he adapted for ER40
collets! I thought it was a particularly smart move but could not find
a description of how he did it.
Michael Koblic,


Why bother unless you already have the ER collets? 5C collets are as
cheap as any other and are the standard for square and hex collet
blocks, end mill grinding fixtures etc


The benefit is the extended range of grip. Much of the stuff I use is
not within the 0.003" or so of the 5C collet size.


If you made parts from standard-sized stock you could leave it
attached to the rod, or at least a short plug on one end.

The 10th picture down. From what I read people use these blocks more
than anything else. I even thought of them and a single 3/4" 5C collet
with a threaded shaft through it to match the Taig chucks.

Picture No. 21 is probably one of the cheaper combinations I have
looked at: Spin indexer and a 5C chuck. My concern there was that I
would run out of space on the X2 table.


If you can find one, the Sherline 5C 4-jaw protrudes less than half as
far. The body is 1.25" thick:
http://www.sherline.com/5c.htm
They aren't for heavy work.

jsw


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On 2011-03-12, wrote:
On Fri, 11 Mar 2011 09:08:59 -0800 (PST), wolfgang
wrote:

[...]

Today there are more options than there were when I built my tooling.
I found the dremel tool speed too high for effective drilling of
steel.


Agreed. Even 1/8" is pushing it with 5000 rpm.

The spacer pin (or bar) is a length of rod that I place between the
bottom edge of the horizontal chuck jaw and the flat of the lathe
bed; this makes for quick-and-dirty indexing. By careful choice of
this spacer you can get 6 divisions quickly depending on your lathe's
design. Certainly 3 div's are easy and a cross hole is a cinch.

Cross drilling does not impose a rotational force on the work piece
and I found that clamping of the lathe spindle, for this operation, is
not necessary. If you are concerned simply hold the spindle, by hand,
against the spacer pin mentioned above.


I need to visualize this. There is a hole directly under the chuck on
my lathe. I guess some kind of a wooden block etc. might do.


Try this ASCII drawing: (view with a fixed pitch font like
Courier to avoid drawing distortion):

______
/ YY\ Octagon shape is the round chuck.
/ _YY \
|XXX/ \ | XXX is jaw which is supported
|XXX\__/ |
# ZZ / YYY & ZZZ are the other two jaws.
#\_____Z/
# #### is the spacer supporting the chuck jaw
^_# ^__
WWW WWW WWW is the cross-section of the lathe bed and ways
WW WW
WWWWWWWWW Smaller hexagon is the hole through the chuck and spindle
WWWWWWWWW
WWW WWW

I was thinking of making a big handle for my 9x20 and attach it to the
other side of the spindle. I thought it would help with threading
amongst other things. I should be able to think of ways to immobilize
the handle in various positions.


Make sure that the handle can be detached or your lathe will
dance all over (and off) the workbench from the imbalance under power.

Enjoy,
DoN.

--
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Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. |
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Besides a variac for universal motor variable speed, the inexpensive
triac/diac-type Router Speed Control units sold by HF and others (maybe $12
on sale) might be a good alternative.
IIRC, the user manual states that the speed control units are for series
field windings, but I haven't read it recently.

I haven't tried one, but the laminate trimmer motor may also work well with
a light/med duty versions of Minarik or KB DC controllers, which would
likely provide better speed regulation (depending upon model and features),
if they're compatible.

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


"Jim Wilkins" wrote in message
...

Instead of locking the spindle you can clamp the divider plate. The
leverage would be better.
The laminate trimmer has 1/4" collets and better mounting surfaces
than a die grinder.
Speed control:
http://www.amptone.com/images/tenmavariac.jpg


Buy one of these, tighten a nut on it and thread the nut:
http://stores.homestead.com/WaldenSpecialties/-strse-31/MT2-Threaded-Arbor,-1-fdsh-2''/Detail.bok
I'd face the arbor flange side of the nut first and saw a slot so it
could be removed if it stays in the chuck. Or leave a hex flange on
the nut.

Why bother unless you already have the ER collets? 5C collets are as
cheap as any other and are the standard for square and hex collet
blocks, end mill grinding fixtures etc.
http://www.micro-machine-shop.com/Co...tm#5C_fixtures
Those are fine for cross-drilling a shaft or milling a square or hex
head.

You could pick a few appropriate sizes for your rod stock and collets,
you don't need a full set. I chose 1/2" and 1" for expensive metal
like O-1, 12L14, 303, 4142 etc.

jsw

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On Mar 12, 7:11*am, "Wild_Bill" wrote:
...
I haven't tried one, but the laminate trimmer motor may also work well with
a light/med duty versions of Minarik or KB DC controllers, which would
likely provide better speed regulation (depending upon model and features),
if they're compatible.
WB


Just tried both, the Variac turns down slower but there isn't much
difference in the low-speed torque (or lack of it).
I used a lamp dimmer, not a router control.

jsw
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Default Dividing head


Wild_Bill wrote:

Besides a variac for universal motor variable speed, the inexpensive
triac/diac-type Router Speed Control units sold by HF and others (maybe $12
on sale) might be a good alternative.
IIRC, the user manual states that the speed control units are for series
field windings, but I haven't read it recently.



In that case, you can use a light dimmer.


--
You can't fix stupid. You can't even put a Band-Aid™ on it, because it's
Teflon coated.
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On Mar 12, 9:22*am, "Michael A. Terrell"
wrote:
Wild_Bill wrote:

Besides a variac for universal motor variable speed, the inexpensive
triac/diac-type Router Speed Control units sold by HF and others (maybe $12
on sale) might be a good alternative.
IIRC, the user manual states that the speed control units are for series
field windings, but I haven't read it recently.


* *In that case, you can use a light dimmer.

--
You can't fix stupid. You can't even put a Band-Aid on it, because it's
Teflon coated.




As others have cautioned above I too would not place a crank handle on
the back end of the lathe spindle. If you really must do this at
least make sure that it is statically balanced!

Instead I have a large hand wheel -6" or so- in diameter that I can
fix at the spindle back end for turning very short threads or
whatever.

The diagram posted by DoN above illustrates the use and position of
the spacer bar/rod as discussed earlier.

Wolfgang


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Fabricating and using a lathe spindle hand crank is a fairly common early
project for a new/beginning lathe user.. many lathe owners use the cranks
regularly, including myself.

It's no problem to unplug the lathe power cord before installing the crank,
which is the method I use, and recommend.

There are many advantages to using a hand crank which is often easier than
using power feed.
Lots of the imported bench lathes don't have spindle speeds low enough to
make power threading short pieces practical.

Not too long ago (a few weeks maybe) someone posted a link to a kit/plans
for building a manual lathe spindle crank that only engages when being
turned by hand.
I haven't seen one of that design, and I would most likely still unplug the
lathe's power cord.

I don't have any trouble unplugging the power cord of my small lathe, since
the power receptacle is located just to the rear of the left end of the
spindle.
I have a lock-out no-power switch position on my other machine.. and I also
pull the power cord plug on that one when doing anything that might result
in injury if the motor were to start.

Thousands of simple actions are dangerous if one is not aware of what
they're doing/paying attention.

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


"wolfgang" wrote in message
...

As others have cautioned above I too would not place a crank handle on
the back end of the lathe spindle. If you really must do this at
least make sure that it is statically balanced!

Instead I have a large hand wheel -6" or so- in diameter that I can
fix at the spindle back end for turning very short threads or
whatever.

The diagram posted by DoN above illustrates the use and position of
the spacer bar/rod as discussed earlier.

Wolfgang

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On Mar 12, 7:19*pm, "Wild_Bill" wrote:
Fabricating and using a lathe spindle hand crank is a fairly common early
project for a new/beginning lathe user.. many lathe owners use the cranks
regularly, including myself.
...


I pull on the leather belt to finish a threading cut.

As part of the hand crank project a centering spider for the left end
of the spindle can be useful. Grizzly puts them on their gunsmith
lathes. Mine is a cheap 1/2" drill chuck with the nose turned down to
fit into the spindle bore. The rod it's centering keeps it in place.

jsw
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On Fri, 11 Mar 2011 17:47:03 -0800 (PST), Jim Wilkins
wrote:

[...]

If you can find one, the Sherline 5C 4-jaw protrudes less than half as
far. The body is 1.25" thick:
http://www.sherline.com/5c.htm
They aren't for heavy work.


Have you ever seen this one:

http://www.proxxontools.com/store/pc...1&idproduct=66

My Dutch sucks but if I am right, this "Verdeelapparaat voor de
MICRO-frees MF 70 en KT 70" can clamp 32 mm outside and the through
hole is 11 mm which is better than the Taig.

The price is right, too...

Michael Koblic,
Campbell River, BC
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On Sat, 12 Mar 2011 09:32:53 -0800 (PST), wolfgang
wrote:

[...]

As others have cautioned above I too would not place a crank handle on
the back end of the lathe spindle. If you really must do this at
least make sure that it is statically balanced!


Or you could just remove it when not needed.

Instead I have a large hand wheel -6" or so- in diameter that I can
fix at the spindle back end for turning very short threads or
whatever.

The diagram posted by DoN above illustrates the use and position of
the spacer bar/rod as discussed earlier.

If I am interpreting this right you can position a 3-jaw chuck in 60
degree intervals using this method. I do not see 90 degrees.

Michael Koblic,
Campbell River, BC


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On Sat, 12 Mar 2011 19:19:14 -0500, "Wild_Bill"
wrote:

Fabricating and using a lathe spindle hand crank is a fairly common early
project for a new/beginning lathe user.. many lathe owners use the cranks
regularly, including myself.

It's no problem to unplug the lathe power cord before installing the crank,
which is the method I use, and recommend.

There are many advantages to using a hand crank which is often easier than
using power feed.
Lots of the imported bench lathes don't have spindle speeds low enough to
make power threading short pieces practical.


You said it!


Not too long ago (a few weeks maybe) someone posted a link to a kit/plans
for building a manual lathe spindle crank that only engages when being
turned by hand.
I haven't seen one of that design, and I would most likely still unplug the
lathe's power cord.

I don't have any trouble unplugging the power cord of my small lathe, since
the power receptacle is located just to the rear of the left end of the
spindle.
I have a lock-out no-power switch position on my other machine.. and I also
pull the power cord plug on that one when doing anything that might result
in injury if the motor were to start.

Thousands of simple actions are dangerous if one is not aware of what
they're doing/paying attention.


It never occurred to me that anyone would leave the power connected
when having the crank in place!

The plans for the crank I saw involve the sort of joint used in bikes
(I don't know the name, it is a bar which is cut diagonally and
connected by a bolt. when tightened it expands inside the spindle).


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On Sat, 12 Mar 2011 16:38:31 -0800 (PST), Jim Wilkins
wrote:

On Mar 12, 7:19*pm, "Wild_Bill" wrote:
Fabricating and using a lathe spindle hand crank is a fairly common early
project for a new/beginning lathe user.. many lathe owners use the cranks
regularly, including myself.
...


I pull on the leather belt to finish a threading cut.


The only time I did (re) threading I just pulled on the workpiece (8"
faceplate).

As part of the hand crank project a centering spider for the left end
of the spindle can be useful. Grizzly puts them on their gunsmith
lathes. Mine is a cheap 1/2" drill chuck with the nose turned down to
fit into the spindle bore. The rod it's centering keeps it in place.

Confused. What is the purpose of the said 1/2" rod?

Michael Koblic,
Campbell River, BC
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On 12 Mar 2011 03:17:47 GMT, "DoN. Nichols"
wrote:

[...]

I was thinking of making a big handle for my 9x20 and attach it to the
other side of the spindle. I thought it would help with threading
amongst other things. I should be able to think of ways to immobilize
the handle in various positions.


Make sure that the handle can be detached or your lathe will
dance all over (and off) the workbench from the imbalance under power.

The thought of a 12" handle going round at 1000 rpm makes my eyes
water...
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On Mar 13, 12:58*am, wrote:
On Fri, 11 Mar 2011 17:47:03 -0800 (PST), Jim Wilkins
...
My Dutch sucks but if I am right, this "Verdeelapparaat voor de
MICRO-frees MF 70 en KT 70" ...
Michael Koblic,


kannitverstan

jsw
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On Mar 13, 1:10*am, wrote:
On Sat, 12 Mar 2011 16:38:31 -0800 (PST), Jim Wilkins
...

As part of the hand crank project a centering spider for the left end
of the spindle can be useful. *Grizzly puts them on their gunsmith
lathes. Mine is a cheap 1/2" drill chuck with the nose turned down to
fit into the spindle bore. The rod it's centering keeps it in place.


Confused. What is the purpose of the said 1/2" rod?

Michael Koblic,
Campbell River, BC


The up-to-1/2" rod is the 3' drill rod etc chucked in the lathe, which
might whip around if uncontrolled. Thin brass brazing rod is the
worst.

jsw
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On Mar 13, 1:03*am, wrote:
On Sat, 12 Mar 2011 09:32:53 -0800 (PST), wolfgang
...
If I am interpreting this right you can position a 3-jaw chuck in 60
degree intervals using this method. I do not see 90 degrees.
Michael Koblic,


Before I got an indexer I put an ignition timing degree wheel behind
the chuck to set an angle and blocked up the chuck jaws to hold it.
The locating and clamping functions were separate and perhaps you
could apply that here, set one jaw either parallel or perpendicular to
a bar lying across the ways.

jsw


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On Mar 13, 1:03*am, wrote:
On Sat, 12 Mar 2011 09:32:53 -0800 (PST), wolfgang

wrote:

[...]

As others have cautioned above I too would not place a crank handle on
the back end of the lathe spindle. *If you really must do this at
least make sure that it is statically balanced!


Or you could just remove it when not needed.

Instead I have a large hand wheel -6" or so- in diameter that I can
fix at the spindle back end for turning very short threads or
whatever.


The diagram posted by DoN above illustrates the use and position of
the spacer bar/rod as discussed earlier.


If I am interpreting this right you can position a 3-jaw chuck in 60
degree intervals using this method. I do not see 90 degrees.

Michael Koblic,
Campbell River, BC



That's what 4-jaw self centering chucks were invented for.:-)).

As I said 3 divs are easy and a cross hole is a cinch.

Wolfgang
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I guess the one advantage to buying one of the HF/other Router Speed
Controls on sale is that the unit is already assembled*, cheaper than
building one from individual components.

*Assembled, in Chinese terms can mean anything close, and the 2 units I
bought maybe 8 years ago needed the hand-soldered connections to be
reflowed, as a few AC wires popped free from their connection points with
almost no effort.

After checking to make sure the wiring and the earth ground are secure, and
not pinched, etc.. the finished unit has a power cord, AC receptacle, hi-lo
switch, speed pot.. and is stated to have a 15 amp capability (although I've
only used them for light duty applications, die grinder etc).

The units can be very versatile for various resistive loads, small universal
motors and various other applications.

Much of the hand-soldered and wave soldered thru-hole connections will be
even more suspect (crap quality) now, for nearly all consumer and commercial
products, since the lead-free solders are being used almost universally
(aviation and a few other industries are exempt).

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


"Jim Wilkins" wrote in message
...
On Mar 12, 7:11 am, "Wild_Bill" wrote:
...
I haven't tried one, but the laminate trimmer motor may also work well
with
a light/med duty versions of Minarik or KB DC controllers, which would
likely provide better speed regulation (depending upon model and
features),
if they're compatible.
WB


Just tried both, the Variac turns down slower but there isn't much
difference in the low-speed torque (or lack of it).
I used a lamp dimmer, not a router control.

jsw

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On Mar 13, 5:10*pm, "Wild_Bill" wrote:
I guess the one advantage to buying one of the HF/other Router Speed
Controls on sale is that the unit is already assembled*, cheaper than
building one from individual components.
...
Much of the hand-soldered and wave soldered thru-hole connections will be
even more suspect (crap quality) now, for nearly all consumer and commercial
products, since the lead-free solders are being used almost universally
(aviation and a few other industries are exempt).
WB


I opened my dozen HF multimeters to calibrate them and didn't see any
bad solder joints. A couple of under-counter fluorescent fixtures from
Lowe's were trash, though.

jsw
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On Sun, 13 Mar 2011 05:03:23 -0700 (PDT), Jim Wilkins
wrote:

On Mar 13, 1:10*am, wrote:
On Sat, 12 Mar 2011 16:38:31 -0800 (PST), Jim Wilkins
...

As part of the hand crank project a centering spider for the left end
of the spindle can be useful. *Grizzly puts them on their gunsmith
lathes. Mine is a cheap 1/2" drill chuck with the nose turned down to
fit into the spindle bore. The rod it's centering keeps it in place.


Confused. What is the purpose of the said 1/2" rod?

Michael Koblic,
Campbell River, BC


The up-to-1/2" rod is the 3' drill rod etc chucked in the lathe, which
might whip around if uncontrolled. Thin brass brazing rod is the
worst.


Right. I's a stock you are working on. I thought for a moment it was a
part of the handle in some way.

Michael Koblic,
Campbell River, BC




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On Sun, 13 Mar 2011 07:43:53 -0700 (PDT), wolfgang
wrote:

[...]

That's what 4-jaw self centering chucks were invented for.:-)).


You haven't seen *my* 4-jaw chuck.
Come to think of it I need one of them, too.

Michael Koblic,
Campbell River, BC
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I just habitually take AC line-powered gear apart whether it's new imported
stuff, or used equipment of any pedigree.

There appear to be fewer China bashing flag wavers around in RCM these days,
but I've often mentioned that it's not that the offshore sources Can't
produce any better quality of goods, but instead, it's just not required to
get average consumers to buy the crap goods (repeatedly).

I have a few very good quality assemblies that originated from China, but
it's not what I generally expect.

Some of us can remember the typical toy-quality goods from Japan in the
1950s, but then Japanese precision design/manufacturing surpassed many other
sources to become a world leader in quality.
I don't expect a great change like that to happen again, not for consumer
goods, at least.

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


"Jim Wilkins" wrote in message
...

I opened my dozen HF multimeters to calibrate them and didn't see any
bad solder joints. A couple of under-counter fluorescent fixtures from
Lowe's were trash, though.

jsw

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That type of expanding anchor/holding joint was the type I fabricated for my
9x20 lathe shortly after I started using it.
Someone mentioned what that type of joint is, but I used it because I
remembered it from a bicycle I had.. it was used where the handlebar stem
was held in the fork tube.

After drilling the stock that's been turned to a slip-fit diameter for the
spindle I.D. (and leaving a stop shoulder), I made the diagonal cut with a
hacksaw, then filed the center hole oval at the contact point on both
sections to allow the two sections to shift on the angled surfaces when the
nut was snugged, effectively locking it in the spindle.

There may be a method of fabricating a hollow version (for longer workpiece
pass-thru), but I haven't encountered a need for one.
A hollow handle extension with an internal thread could be added to the left
spindle end, in place of the nut that's used to set/adjust the spindle
bearing preload (with a soft-point setscrew or other means of preventing
overtightening of the preload).

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


wrote in message
news
Lots of the imported bench lathes don't have spindle speeds low enough to
make power threading short pieces practical.


You said it!

It never occurred to me that anyone would leave the power connected
when having the crank in place!

The plans for the crank I saw involve the sort of joint used in bikes
(I don't know the name, it is a bar which is cut diagonally and
connected by a bolt. when tightened it expands inside the spindle).


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On Mar 14, 7:20*am, "Wild_Bill" wrote:
That type of expanding anchor/holding joint was the type I fabricated for my
9x20 lathe shortly after I started using it.
Someone mentioned what that type of joint is, but I used it because I
remembered it from a bicycle I had.. it was used where the handlebar stem
was held in the fork tube.
...
WB


That type of fitting presses the spindle tube oval, not good at a
bearing.

I'd consider two concentric tubes, the inner one having a taper on the
end that wedges the slit outer one evenly tight against the spindle ID
somewhere far from bearings. It would work like a ball hole gage, but
have an over-center cam instead of a slow-acting screw to operate it.
The tapered cone could be a separate piece that screws on, giving an
easy tension adjustment.

jsw
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Default Dividing head

I tried an expanding mandrel type before choosing to make the other
angled-cut type.
The expanding mandrel was a tapered plug at the end of a section of
all-thread which was pulled into the split mandrel, but it didn't hold very
well, and was fiddly to release, so I made the other, angled-cut type.

The angled-cut type works well with only a moderate amount of torque to
secure it, and the cut line isn't placed at the location of a bearing, but
farther inside the spindle.
I would expect the grip to be spread out over much of the entire length of
the "fastener".. but possibly not.

When I locate a good heavy duty motor (probably PM DC) for the 9x20 lathe,
I'll convert it as I did the other machine, and the hand crank will likely
be reused for something else.

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


"Jim Wilkins" wrote in message
...
On Mar 14, 7:20 am, "Wild_Bill" wrote:
That type of expanding anchor/holding joint was the type I fabricated for
my
9x20 lathe shortly after I started using it.
Someone mentioned what that type of joint is, but I used it because I
remembered it from a bicycle I had.. it was used where the handlebar stem
was held in the fork tube.
...
WB


That type of fitting presses the spindle tube oval, not good at a
bearing.

I'd consider two concentric tubes, the inner one having a taper on the
end that wedges the slit outer one evenly tight against the spindle ID
somewhere far from bearings. It would work like a ball hole gage, but
have an over-center cam instead of a slow-acting screw to operate it.
The tapered cone could be a separate piece that screws on, giving an
easy tension adjustment.

jsw

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