Been Googling a bit on this and not finding what I want, thought I'd ask
just in case anyone might happen to know.

I have a DiAcro 24" finger brake and shear, and want to make some quick
adjustable back gauges. I made a back gauge for the 12" shear of a
former employer years ago, using a 1/4-20 screw and a digital caliper
for measuring. Worked great, but slow on the adjustment.

If I can find a rack with a pitch equal to some standard dimension,
preferably .100 or .200, or some even mm pitch, that would work great.

Got the idea after making a vastly improved travel stop for my Roll-In
saw. Bolted a section of rack to the right side frame, and a stop with a
short section of rack and a clamp screw. There's also a fine adjustment
screw that bears on the vertical saw frame. I use this saw a lot for
removing bulk material instead of milling it, so something easier than
the wobbly stock stop was needed. Now I'm looking to apply the principle
elsewhere.

Thanks,


Jon

On Dec 2, 1:45*pm, Jon Anderson wrote:
Been Googling a bit on this and not finding what I want, thought I'd ask
just in case anyone might happen to know.

I have a DiAcro 24" finger brake and shear, and want to make some quick
adjustable back gauges. I made a back gauge for the 12" shear of a
former employer years ago, using a 1/4-20 screw and a digital caliper
for measuring. Worked great, but slow on the adjustment.

If I can find a rack with a pitch equal to some standard dimension,
preferably .100 or .200, or some even mm pitch, that would work great.

Got the idea after making a vastly improved travel stop for my Roll-In
saw. Bolted a section of rack to the right side frame, and a stop with a
short section of rack and a clamp screw. There's also a fine adjustment
screw that bears on the vertical saw frame. I use this saw a lot for
removing bulk material instead of milling it, so something easier than
the wobbly stock stop was needed. Now I'm looking to apply the principle
elsewhere.

Thanks,

Jon

Quick-adjusting nuts are simple to make. The body is a short cylinder
with a blind hole for the plunger. Cross-drill and tap the plunger,
then mill out the threads on the side that protrudes. Drop a
compression spring into the hole, install and press the plunger and
and slide it onto the threaded rod.
http://hqtinc.com/ProductImages/1053.jpg

jsw

On Thu, 02 Dec 2010 10:45:01 -0800, Jon Anderson
wrote:

Been Googling a bit on this and not finding what I want, thought I'd ask
just in case anyone might happen to know.

I have a DiAcro 24" finger brake and shear, and want to make some quick
adjustable back gauges. I made a back gauge for the 12" shear of a
former employer years ago, using a 1/4-20 screw and a digital caliper
for measuring. Worked great, but slow on the adjustment.

If I can find a rack with a pitch equal to some standard dimension,
preferably .100 or .200, or some even mm pitch, that would work great.

Timing belt pitch is based on the linear spacing of the teeth on the
belt, unlike spur gears, which are designed around even numbers of
teeth on rationally dimensioned diameters. Though it won't be quite as
stiff and accurate as a gear rack, you can use a stretched timing belt
as a rack. English pitches are .200, .375, .500, etc. There are also
metric timing belts, as well as alternative tooth designs that are
stronger than the traditional trapezoidal teeth. If you consider this
alternative, I'd recommend using a steel corded urethane belt.

--
Ned Simmons

On Thu, 02 Dec 2010 10:45:01 -0800, Jon Anderson
wrote:

Been Googling a bit on this and not finding what I want, thought I'd ask
just in case anyone might happen to know.

I have a DiAcro 24" finger brake and shear, and want to make some quick
adjustable back gauges. I made a back gauge for the 12" shear of a
former employer years ago, using a 1/4-20 screw and a digital caliper
for measuring. Worked great, but slow on the adjustment.

If I can find a rack with a pitch equal to some standard dimension,
preferably .100 or .200, or some even mm pitch, that would work great.
snip
==========
see
http://www.teausa.net/index.aspx?page=20
http://www.ametric.com/Products/tabid/57/Default.aspx
https://sdp-si.com/eStore/Direct.asp?GroupID=479
https://sdp-si.com/eStore/Direct.asp?GroupID=480



-- Unka George (George McDuffee)
...............................
The past is a foreign country;
they do things differently there.
L. P. Hartley (1895-1972), British author.
The Go-Between, Prologue (1953).

Jon Anderson wrote:

Been Googling a bit on this and not finding what I want, thought I'd ask
just in case anyone might happen to know.

I have a DiAcro 24" finger brake and shear, and want to make some quick
adjustable back gauges. I made a back gauge for the 12" shear of a
former employer years ago, using a 1/4-20 screw and a digital caliper
for measuring. Worked great, but slow on the adjustment.

If I can find a rack with a pitch equal to some standard dimension,
preferably .100 or .200, or some even mm pitch, that would work great.

Got the idea after making a vastly improved travel stop for my Roll-In
saw. Bolted a section of rack to the right side frame, and a stop with a
short section of rack and a clamp screw. There's also a fine adjustment
screw that bears on the vertical saw frame. I use this saw a lot for
removing bulk material instead of milling it, so something easier than
the wobbly stock stop was needed. Now I'm looking to apply the principle
elsewhere.

Thanks,

Jon

Add an overdrive to the adjustment crank or use a power adjustment and
the easier and less expensive screw drive. Heck even a direct crank
wheel with a 1/4" hex extension in the middle so you can coarse adjust
with a cordless drill/driver and then finish by hand.

On 12/2/2010 11:06 AM, Jim Wilkins wrote:

Quick-adjusting nuts are simple to make. The body is a short cylinder
with a blind hole for the plunger.

Yeah, familiar with those. I didn't go into enough detail. I want to use
the rack for positive quick adjustment, but be able to make fine
adjustments, with a dial indicator to arrive at final dimension.
Idea is to be able to calibrate back gauge, then be able to quickly
shear or bend to size. Well, on the finger brake it's not so cut and
dried, but you get the picture.

I believe DiAcro uses the quick adjusting nuts stock, but I didn't get
back gauges with either unit.


Jon

On 12/2/2010 11:15 AM, Ned Simmons wrote:

Though it won't be quite as stiff and accurate as a gear rack, you
can use a stretched timing belt as a rack. English pitches are .200,
.375, .500, etc.

Appreciate the suggestion! But timing belts don't lock tooth to tooth
like a cut rack will. I'm looking for some real precision and
repeatability. I see multiple applications for the idea, if I can find
rack with an appropriate pitch. Of course, if I had time, I could make
my own racks, but that sort of free time is a long way off...


Jon

On 12/2/2010 11:29 AM, F. George McDuffee wrote:

see http://www.teausa.net/index.aspx?page=20
snip

Sigh, looks like I'm out of luck. Well, maybe tonight I'll Google linear
Hirth coupling and see if I can find anything. Don't need that level of
precision, but that's essentially what I want.

Or, back to the drawing board...


Jon

Jon: use any dimension rack and buy a calculator? $10 bucks for a fancy
one.

Hul

Jon Anderson wrote:
On 12/2/2010 11:29 AM, F. George McDuffee wrote:

see http://www.teausa.net/index.aspx?page=20
snip

Sigh, looks like I'm out of luck. Well, maybe tonight I'll Google linear
Hirth coupling and see if I can find anything. Don't need that level of
precision, but that's essentially what I want.

Or, back to the drawing board...


Jon

On Dec 2, 3:26*pm, Jon Anderson wrote:

I believe DiAcro uses the quick adjusting nuts stock, but I didn't get
back gauges with either unit.

Jon

The quick nuts adjust like regular ones. You could make your own back
gauge from 1/2-20 threaded rod and Bridgeport nuts.

jsw

On Dec 2, 12:45*pm, Jon Anderson wrote:
Been Googling a bit on this and not finding what I want, thought I'd ask
just in case anyone might happen to know.

I have a DiAcro 24" finger brake and shear, and want to make some quick
adjustable back gauges. I made a back gauge for the 12" shear of a
former employer years ago, using a 1/4-20 screw and a digital caliper
for measuring. Worked great, but slow on the adjustment.

If I can find a rack with a pitch equal to some standard dimension,
preferably .100 or .200, or some even mm pitch, that would work great.

Got the idea after making a vastly improved travel stop for my Roll-In
saw. Bolted a section of rack to the right side frame, and a stop with a
short section of rack and a clamp screw. There's also a fine adjustment
screw that bears on the vertical saw frame. I use this saw a lot for
removing bulk material instead of milling it, so something easier than
the wobbly stock stop was needed. Now I'm looking to apply the principle
elsewhere.

Thanks,

Jon

I recently got an old Unisaw table saw that uses a rack and pinion
system for adjusting the fence. I think that Craftsman used the same
system on some of their old table saws too. Maybe if you find an old
Craftsman table saw that has one of those, you can adapt it to use as
a stop for your shear.

On 12/2/2010 8:28 PM, Denis G. wrote:

Maybe if you find an old Craftsman table saw that has one of those,
you can adapt it to use as a stop for your shear.

Wasn't looking to use a rack and pinion for adjustment, rather using a
long section of rack and an opposed section in a clamp setup for rapid
adjustment to known locations in some even increment.
But dual racks with pinions, and a digital caliper would make for rapid
adjustment and precision.

It's just that the rack seemed like a neat idea.... I should post a
picture of the stop I made for the Roll-In saw. Probably will after I
finish a related accessory that will also use the rack.


Jon

On Dec 2, 11:27*pm, Jon Anderson wrote:
On 12/2/2010 8:28 PM, Denis G. wrote:

Maybe if you find an old Craftsman table saw that has one of those,
you can adapt it to use as a stop for your shear.

Wasn't looking to use a rack and pinion for adjustment, rather using a
long section of rack and an opposed section in a clamp setup for rapid
adjustment to known locations in some even increment.
But dual racks with pinions, and a digital caliper would make for rapid
adjustment and precision.

It's just that the rack seemed like a neat idea.... I should post a
picture of the stop I made for the Roll-In saw. Probably will after I
finish a related accessory that will also use the rack.

Jon

Yes, I'd like to see it when you get the chance.

On Dec 2, 10:27*pm, Jon Anderson wrote:
On 12/2/2010 8:28 PM, Denis G. wrote:

Maybe if you find an old Craftsman table saw that has one of those,
you can adapt it to use as a stop for your shear.

Wasn't looking to use a rack and pinion for adjustment, rather using a
long section of rack and an opposed section in a clamp setup for rapid
adjustment to known locations in some even increment.
But dual racks with pinions, and a digital caliper would make for rapid
adjustment and precision.

It's just that the rack seemed like a neat idea.... I should post a
picture of the stop I made for the Roll-In saw. Probably will after I
finish a related accessory that will also use the rack.

Jon

I saw something like that at a woodworking show one time, was a whole
system, used plastic racks for positioning workpieces on saws, router
tables and drill presses. Incra-jig or something like that.

Stan

On Thu, 02 Dec 2010 12:32:06 -0800, Jon Anderson
wrote:

On 12/2/2010 11:15 AM, Ned Simmons wrote:

Though it won't be quite as stiff and accurate as a gear rack, you
can use a stretched timing belt as a rack. English pitches are .200,
.375, .500, etc.

Appreciate the suggestion! But timing belts don't lock tooth to tooth
like a cut rack will. I'm looking for some real precision and
repeatability. I see multiple applications for the idea, if I can find
rack with an appropriate pitch. Of course, if I had time, I could make
my own racks, but that sort of free time is a long way off...

I see now from one of your later posts what you're trying to do.
Trapezoidal or AT tooth belts won't lock together in that fashion, but
at least some of the other tooth forms will. I have a 3mm pitch HTD
belt here that meshes face to face with no play.

--
Ned Simmons