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I tried to cut my first threads, but couldn't get synched up for
additional cuts. I figured out the dial needs to be adjusted to begin
with to even get it to start turning, but it stops turning when I
engage the lead screw nut. Doesn't it need to turn the whole time,
even when I move the tool back to the beginning of the cut? If so, how
do I adjust this thing to keep it turning?
Ed

That threw me off at first also, but no. As soon as you engage the
leadscrew, the threading will stop turning. Since the dial is moving
at the same speed as the leadscrew, it won't be changing. The purpose
of the threading dial is so you can REengage it at the same relative
position.

Mike

--- In 7x12minilathe@..., "Ed" <edo@...> wrote:

I tried to cut my first threads, but couldn't get synched up for
additional cuts. I figured out the dial needs to be adjusted to begin
with to even get it to start turning, but it stops turning when I
engage the lead screw nut. Doesn't it need to turn the whole time,
even when I move the tool back to the beginning of the cut? If so, how
do I adjust this thing to keep it turning?

You don't, at least on my Cummins 7x12. This disturbed me at first,
but it doesn't matter.

I haven't done a lot of threading, but what I have done has been
successful (one exception while learning) :-). My dial quits turning
when I engage the half nuts, which isn't a problem.

What you need to know is what marks on the dial are for what thread
(some have multiple number that are right, just use the same one each
time).

Make a very light first cut and check it with a thread gauge. Learned
that the hard way when I got the gear sequence for a metric thread
wrong :-).

Back off the cross slide enough to clear, making sure you note the
setting (I set mine to zero for the first pass, just *barely* touching).

Move the carriage back behind the work.

Move the cross slide back in for the next cut ( adding .002-.003 each
pass, is what I used). Yes, it takes a few passes :-).

Watch the dial and when it gets to the right number for the thread,
re-engage the half nuts. It doesn't matter how far behind the part
you are.

Repeat until you get the desired depth.

After the trepidation of getting the gears set up right, figuring out
the dial and doing the first one, it is pretty easy, just somewhat
tedious. Not afraid of the process any more :)!

Jose's video on the subject went a long way to getting here :-)!

Another option, that I haven't used, is to back off the cross slide
and run the lathe in reverse without disengaging the half nuts until
you get past the end of the part.

It is a *very* nice feeling when you get that first threaded part out
and it works!

Hope this helps!

Take care, Vikki.

G'day Ed.
Firstly, congratulations on giving it a go.
You haven't told us whether you are cutting imperial (inch) or metric
threads. For the moment I will assume you are cutting imperial with an
imperial lead screw.
Firstly make sure the thread chasing dial pinion engages the lead
screw, a screw in the side of the dial block allows the pinion to be
swung into the lead screw.
As you traverse the saddle the dial will rotate, also if you drive the
lead screw without the saddle moving the screw will rotate. If you
engage the half nuts then the dial will remain stopped.
When cutting a thread on the first pass engage the half nuts when the
dial is at a number against the line on the block, any number, but 1 is
the best. Do the pass, withdraw the tool and disengage the half nuts.
Return the saddle to the start position, doesn't have to be precise,
and adjust the tool for the next cut. With the lathe running the dial
will have been turning through all this. Here is the crunch. watch the
dial and as the number (eg "1") comes up against the line on the block
gently engage the half nuts, the dial should stop with the number at or
near the line on the dial block.
Using "1" as the number will work for all common (I repeat common, eg
UNC & UNF) threads. As you get more confident you start using other
number combinations on the dial appropriate to different thread pitches
(see the table on the change gear cover). This saves time as you can
engage the half nuts at say 3, 6, 9 & 12, ie you don't have to wait
for a full turn of the dial each cut. Once you get the hang of this
your confidence level will take a quantum leap.
Metric threads are somewhat more difficult to understand but there is
an excellent treatise in www.mini-lathe.org.uk; read it anyway it is
good stuff.
My morning coffee has finished so I had better get on with work.

One good turn deserves another.
Regards,
Ian


is--- In 7x12minilathe@..., "Ed" <edo@...> wrote:

Thanks for the advice. I think I'm getting it figured out. It helps
now that I changed gears to give me a recognizable thread - don't know
what TPI the stock gears give you, but it isn't pretty. Getting the
screw engaged at the same spot is a little tricky, but I'm sure it'll
come with practice - especially at higher speeds.

I'm not trying to thread anything useful yet, just practicing and
having fun!

The handiest threading accessory you can make is a handcrank!
Particularly on short, shouldered pieces turning the lathe by hand
gives more torque & much better control.

The threading dial is only useful on imperial threads which are
multiples of x/2 (assuming an imperial lead screw.) For metric
approximations you pretty much have to keep the half-nuts engaged
during the entire process. After you do that a couple of times, you'll
find it's quicker & easier to do all your threading that way. On big
lathes/long threads, it's not true; on these machines, it mostly is.

Roy

Does anybody know a procudure how to make a handcrank? A while ago I ran across a procedure on one of the lathe/minilathe/machining websites. But I do not remember any more which website that was.
Thank you.
Gregor Stransky, San Antonio, Texas

The most common methods use something that expands into the HS bore,
attached to the actual handcrank. One style uses a diagonally cut
piece that expands into the HS bore when it's tightened; exactly like
a bicycle handlebar adjuster. The other style uses a double-
expanding concrete anchor to grip the bore. You'll want about a 6"
lever arm with some flavor of knob. If you can get one, an old valve
handwheel works nicely, as does a defunct ball joint in a piece of
flat stock.



Roy

--- In 7x12minilathe@..., <gregorstransky@...> wrote:

Does anybody know a procudure how to make a handcrank? A while ago

I ran

across a procedure on one of the lathe/minilathe/machining

websites. But I

do not remember any more which website that was.
Thank you.
Gregor Stransky, San Antonio, Texas

----- Original Message -----
From: "roylowenthal" <roylowenthal@...>
To: <7x12minilathe@...>
Sent: Sunday, March 25, 2007 9:15 PM
Subject: [7x12minilathe] Re: Threading and using the Dial


The handiest threading accessory you can make is a handcrank!
Particularly on short, shouldered pieces turning the lathe by hand
gives more torque & much better control.

Hi Roy,

I was wondering about utilising the locknut on the end of the
spindle. This would have the advantage of keeping the spindle free
for long jobs. Anyone else looked at this?

John


--- In 7x12minilathe@..., "roylowenthal"
<roylowenthal@...> wrote:

The most common methods use something that expands into the HS

bore,

attached to the actual handcrank. One style uses a diagonally cut
piece that expands into the HS bore when it's tightened; exactly

like

a bicycle handlebar adjuster. The other style uses a double-
expanding concrete anchor to grip the bore. You'll want about a

6"

lever arm with some flavor of knob. If you can get one, an old

valve

handwheel works nicely, as does a defunct ball joint in a piece of
flat stock.



Roy

--- In 7x12minilathe@..., <gregorstransky@> wrote:

Does anybody know a procudure how to make a handcrank? A while

ago

I ran

across a procedure on one of the lathe/minilathe/machining

websites. But I

do not remember any more which website that was.
Thank you.
Gregor Stransky, San Antonio, Texas

----- Original Message -----
From: "roylowenthal" <roylowenthal@>
To: <7x12minilathe@...>
Sent: Sunday, March 25, 2007 9:15 PM
Subject: [7x12minilathe] Re: Threading and using the Dial


The handiest threading accessory you can make is a handcrank!
Particularly on short, shouldered pieces turning the lathe by

hand

gives more torque & much better control.

The proponent of that is Mike Tagliari, he did it to allow turning
long pieces with a handcrank. The only downside is having to make
sure you don't move the nuts, changing the HS bearing preload.

Roy

--- In 7x12minilathe@..., "born4something" <ajs@...>
wrote:

Hi Roy,

I was wondering about utilising the locknut on the end of the
spindle. This would have the advantage of keeping the spindle free
for long jobs. Anyone else looked at this?

John


--- In 7x12minilathe@..., "roylowenthal"
<roylowenthal@> wrote:

The most common methods use something that expands into the HS

bore,

attached to the actual handcrank. One style uses a diagonally

cut

piece that expands into the HS bore when it's tightened; exactly

like

a bicycle handlebar adjuster. The other style uses a double-
expanding concrete anchor to grip the bore. You'll want about a

6"

lever arm with some flavor of knob. If you can get one, an old

valve

handwheel works nicely, as does a defunct ball joint in a piece

of

flat stock.



Roy

--- In 7x12minilathe@..., <gregorstransky@> wrote:

Does anybody know a procudure how to make a handcrank? A while

ago

I ran

across a procedure on one of the lathe/minilathe/machining

websites. But I

do not remember any more which website that was.
Thank you.
Gregor Stransky, San Antonio, Texas

----- Original Message -----
From: "roylowenthal" <roylowenthal@>
To: <7x12minilathe@...>
Sent: Sunday, March 25, 2007 9:15 PM
Subject: [7x12minilathe] Re: Threading and using the Dial


The handiest threading accessory you can make is a handcrank!
Particularly on short, shouldered pieces turning the lathe by

hand

gives more torque & much better control.

--- In 7x12minilathe@..., "roylowenthal"
<roylowenthal@...> wrote:

The proponent of that is Mike Tagliari, he did it to allow turning
long pieces with a handcrank. The only downside is having to make
sure you don't move the nuts, changing the HS bearing preload.

Roy

And using a hand crank with a long bar poked through the middle must
be a PITA. But a nice option when necessary. <G> Good argument for a
big cast valve wheel!

I just checked. My spindle has a full 4mm of thread on the outside
of the locknut. That should be sufficient to attach a threaded crank
onto which would tighten under load in the forward direction. That
begs the question of how to secure it to allow reverse. Maybe a pin
into a hole or a slot cut in the spindle end? To avoid loosening the
spindle lock nut during removal a collet spanner could be used.

Thinking through the keyboard here. Is this the makings of a viable
crank idea?

--- In 7x12minilathe@..., "born4something" <ajs@>
wrote:

Hi Roy,

I was wondering about utilising the locknut on the end of the
spindle. This would have the advantage of keeping the spindle

free

for long jobs. Anyone else looked at this?

John


--- In 7x12minilathe@..., "roylowenthal"
<roylowenthal@> wrote:

The most common methods use something that expands into the HS

bore,

attached to the actual handcrank. One style uses a diagonally

cut

piece that expands into the HS bore when it's tightened;

exactly

like

a bicycle handlebar adjuster. The other style uses a double-
expanding concrete anchor to grip the bore. You'll want about

a

6"

lever arm with some flavor of knob. If you can get one, an

old

valve

handwheel works nicely, as does a defunct ball joint in a

piece

of

flat stock.



Roy

--- In 7x12minilathe@..., <gregorstransky@> wrote:

Does anybody know a procudure how to make a handcrank? A

while

ago

I ran

across a procedure on one of the lathe/minilathe/machining

websites. But I

do not remember any more which website that was.
Thank you.
Gregor Stransky, San Antonio, Texas

----- Original Message -----
From: "roylowenthal" <roylowenthal@>
To: <7x12minilathe@...>
Sent: Sunday, March 25, 2007 9:15 PM
Subject: [7x12minilathe] Re: Threading and using the Dial


The handiest threading accessory you can make is a handcrank!
Particularly on short, shouldered pieces turning the lathe

by

hand

gives more torque & much better control.

G'day John.

You are lucky to have a significant length of thread left on the end
of your spindle, I have next to none.
I don't see the expanding shaft as being too difficult, pull the
handle bars out of the neck of a bike to see what I mean. You can't
make it longer than you can drill anyway.

I am now considering this for an indexer attachment using the change
gears. What I plan is a close fitting shaft (to the inside of the
spindle) with a relatively steep taper towards the outboard end to
ensure centering. This would be turned down at the end to the gear
diameter and a key way cut in it. The whole would be drilled through
to take a 8mm bolt. The locking mechanism would be two parts of the
same diameter as the shaft(close fit in the spindle) made by turning
down one piece then making an inclined cut through it. The outboard
piece would be drilled through over size for the 8mm bolt and the
other drilled and tapped for the 8mm bolt. Tightening the bolt would
force the two pieces to the walls of the spindle thus securing the
indexer. Being two pieces the opposing forces should not misalign the
attachment too much.
This same method could be used to mount the hand wheel to the spindle
without risking your spindle bearing preload. There would still be
room for longer work pieces or an excuse to use the steadies.

I must make a hand wheel/ crank to save using the chuck key in the
chuck as a tommy bar to rotate the work when taping.

One good turn (even by a crank) deserves another.
Regards,
Ian

--- In 7x12minilathe@..., "born4something" <ajs@...>
wrote:

--- In 7x12minilathe@..., "roylowenthal"
<roylowenthal@> wrote:

The proponent of that is Mike Tagliari, he did it to allow

turning

long pieces with a handcrank. The only downside is having to

make

sure you don't move the nuts, changing the HS bearing preload.

Roy

And using a hand crank with a long bar poked through the middle

must

be a PITA. But a nice option when necessary. <G> Good argument for

a

big cast valve wheel!

I just checked. My spindle has a full 4mm of thread on the outside
of the locknut. That should be sufficient to attach a threaded

crank

onto which would tighten under load in the forward direction. That
begs the question of how to secure it to allow reverse. Maybe a pin
into a hole or a slot cut in the spindle end? To avoid loosening

the

spindle lock nut during removal a collet spanner could be used.

Thinking through the keyboard here. Is this the makings of a viable
crank idea?

Hi Ian,

I have seen bike handlebars done that way. My thoughts on such a
locking mechanism were more on a par with a masonry bolt. Slit your
close fitting shaft - even crudely with a hack saw - at every 90
degrees say. Then turn a cone shape to partially sit inside your
close fitting shaft as a spreader. Tap at 8mm for the draw bolt.
That should eliminate any misalignment during tightening. In either
case, during removal you need to loosen the 8mm bolt but NOT use it
to pull the close-fitting shaft out of the spindle as that would
tend to re-lock it.

Just a thought. Both approaches lend themselves to reversal. Turn
the 8mm bolt around and use an off-the-shelf nut on the outer end.
Key the inner end to the cone or wedge section by milling a slot or
pinning. This avoids cutting a long thread with any associated
angst. It also means both bolt & nut can be high tensile with little
chance of ever stripping and easy replacement anyway. Or were you
figuring on cutting the 8mm thread in the lathe?

John


--- In 7x12minilathe@..., "steam4ian" <fosterscons@...>
wrote:

G'day John.

You are lucky to have a significant length of thread left on the

end

of your spindle, I have next to none.
I don't see the expanding shaft as being too difficult, pull the
handle bars out of the neck of a bike to see what I mean. You

can't

make it longer than you can drill anyway.

I am now considering this for an indexer attachment using the

change

gears. What I plan is a close fitting shaft (to the inside of the
spindle) with a relatively steep taper towards the outboard end to
ensure centering. This would be turned down at the end to the gear
diameter and a key way cut in it. The whole would be drilled

through

to take a 8mm bolt. The locking mechanism would be two parts of

the

same diameter as the shaft(close fit in the spindle) made by

turning

down one piece then making an inclined cut through it. The

outboard

piece would be drilled through over size for the 8mm bolt and the
other drilled and tapped for the 8mm bolt. Tightening the bolt

would

force the two pieces to the walls of the spindle thus securing the
indexer. Being two pieces the opposing forces should not misalign

the

attachment too much.
This same method could be used to mount the hand wheel to the

spindle

without risking your spindle bearing preload. There would still be
room for longer work pieces or an excuse to use the steadies.

I must make a hand wheel/ crank to save using the chuck key in the
chuck as a tommy bar to rotate the work when taping.

One good turn (even by a crank) deserves another.
Regards,
Ian

--- In 7x12minilathe@..., "born4something" <ajs@>
wrote:

--- In 7x12minilathe@..., "roylowenthal"
<roylowenthal@> wrote:

The proponent of that is Mike Tagliari, he did it to allow

turning

long pieces with a handcrank. The only downside is having to

make

sure you don't move the nuts, changing the HS bearing preload.

Roy

And using a hand crank with a long bar poked through the middle

must

be a PITA. But a nice option when necessary. <G> Good argument

for

a

big cast valve wheel!

I just checked. My spindle has a full 4mm of thread on the

outside

of the locknut. That should be sufficient to attach a threaded

crank

onto which would tighten under load in the forward direction.

That

begs the question of how to secure it to allow reverse. Maybe a

pin

into a hole or a slot cut in the spindle end? To avoid loosening

the

spindle lock nut during removal a collet spanner could be used.

Thinking through the keyboard here. Is this the makings of a

viable

crank idea?

G'day Johm

Your proposal would work, but I would make two mods as I am concerned
the shaft may be difficult to release. Firstly I would cut a groove
at the point where the hacksaw cuts end, this will focus the bending
to this point. Secondly I would have turned the end to a slight
taper, a few thou thinner at the end so that when the wedge nut is
released the expanded part would contract to under the shaft diameter.

I haven't considered the bolt but would probably use a commercial
product. My local hardware store sells a range of 8mm metric bolts up
to 150mm long, they are not high tensile but are forged ane quite
tough. Most hardware stores have a range of imperial threaded rod
available up to 1/2" diameter, I think the thread is Whitworth.
I don't see any difficulty cutting an 8mm thread as I have already
cut a 3/8 x 24 thread plus smaller metric threads successfully. I
found I could do it under power and didn't meed a crank or handwheel;
you do need to design a runout groove for the thread cutting tool
when cutting to a shoulder and have you whits about you.

Regarding the coned nut or end, I don't see any need to pin it to the
shaft, friction is a mighty thing!

Anyhow, all this is hyperthetical and for me about 3 projects away.

One good turn deserves another.
Regards
Ian

--- In 7x12minilathe@..., "born4something" <ajs@...>
wrote:

Hi Ian,

I have seen bike handlebars done that way. My thoughts on such a
locking mechanism were more on a par with a masonry bolt. Slit your
close fitting shaft - even crudely with a hack saw - at every 90
degrees say. Then turn a cone shape to partially sit inside your
close fitting shaft as a spreader. Tap at 8mm for the draw bolt.
That should eliminate any misalignment during tightening. In either
case, during removal you need to loosen the 8mm bolt but NOT use it
to pull the close-fitting shaft out of the spindle as that would
tend to re-lock it.

Just a thought. Both approaches lend themselves to reversal. Turn
the 8mm bolt around and use an off-the-shelf nut on the outer end.
Key the inner end to the cone or wedge section by milling a slot or
pinning. This avoids cutting a long thread with any associated
angst. It also means both bolt & nut can be high tensile with

little

chance of ever stripping and easy replacement anyway. Or were you
figuring on cutting the 8mm thread in the lathe?

I made a mandrel with a taper lock to hold a handwheel (9" OD, cast
iron)recycled from a discarded NordicTrac as shown here:


The groove at the end of the saw cuts makes it work much more easily.
Tapering the end isn't necessary, the movement is only a few thou so
the steel won't take a set. It takes about a half turn of the nut to
lock it and it never slips. However, the shallow taper is not
self-releasing so after turning the bolt CCW a half turn I tap the end
of the bolt with my hand - it doesn't take much but it does need that tap.

The large part of the mandrel spaces the handwheel out from the gear
cover, I often use the handwheel with the cover in place. The hole in
the cover had to be enlarged with the Dremel to pass this.

I prefer the handwheel to a crank because the gripping point is always
in the same spot. The handwheel sees a lot of use when threading. Max
RPM with it mounted is about 250 because of a modest balance problem
so I seldom use power with the wheel mounted - except I back taps out
slowly with power.

John

Hi Ian,

--- In 7x12minilathe@..., "steam4ian" <fosterscons@...>
wrote:

Regarding the coned nut or end, I don't see any need to pin it to

the

shaft, friction is a mighty thing!

My concern was that friction has a covert relationship to the Murphy
family. It might let you tighten things, then slip when you want
things to loosen. As you say, it's hypothetical at this stage. Time
will reveal all.

John

Looking at the scant 4mm protrusion on mine makes me a little leery
of expecting too much from it. I could see some sort of locking
device, either a removable pin or clamping a split threaded piece.

Roy

--- In 7x12minilathe@..., "born4something" <ajs@...>
wrote:

--- In 7x12minilathe@..., "roylowenthal"
<roylowenthal@> wrote:

The proponent of that is Mike Tagliari, he did it to allow

turning

long pieces with a handcrank. The only downside is having to

make

sure you don't move the nuts, changing the HS bearing preload.

Roy

And using a hand crank with a long bar poked through the middle

must

be a PITA. But a nice option when necessary. <G> Good argument for

a

big cast valve wheel!

I just checked. My spindle has a full 4mm of thread on the outside
of the locknut. That should be sufficient to attach a threaded

crank

onto which would tighten under load in the forward direction. That
begs the question of how to secure it to allow reverse. Maybe a pin
into a hole or a slot cut in the spindle end? To avoid loosening

the

spindle lock nut during removal a collet spanner could be used.

Thinking through the keyboard here. Is this the makings of a viable
crank idea?

--- In 7x12minilathe@..., "born4something" <ajs@>
wrote:

Aren't masonry bolts made for one time use? The ones I've used (in
concrete of all places) were made of soft metal - I wouldn't think
you'd be able to back it out. Your isn't permanent is it?
Ed

This is exactly what I used. Fortunately the masonary bolt used, is

the right diameter for mounting the gears on. Just add a plunger of
some sort and you have a simple indexing attachmeny as well !

HTH
Ellis

Ed wrote.......Aren't masonry bolts made for one time use? The ones I've used (in concrete of all places) were made of soft metal - I wouldn't think you'd be able to back it out. Your isn't permanent is it?.......

No it's not permanent. As I understand it, the soft metal is to 'bite' into the rough walls of the masonery using a force far greater than required to 'anchor' it in the headstock spindle. So with lesser force against a smooth surface, it works just great. However, you can cover the expanding part with some rubber to give a better grip.
HTH
Ellis