Maybe someone here in RCM has some experience with radius grinding fixtures,
and would like to share some information about using them to grind parts or
sharpening cutters.

I picked this radius grinding/indexing accessory up on eBay. I had no
previous knowlege of the Holdridge or Romer names or tooling.

It's described as being a Romer I Radial Grinding Fixture for universal (T &
C) tool and cutter grinders which I don't presently own) but I was curious
about it's versatility.

This is a radius grinding spin index-type accessory, not a Holdridge ball
turning accessory for a lathe toolpost.

http://www.kwagmire.com/tools/Radius...er/romer1.html

As far as cutting tool geometry goes, would this sort of information be in
Machinerys Handbook?
I have some nice HSS B&S Brown & Sharpe mill arbor cutters that need
resharpened but I don't have any experience with this type of grinding.

I read a reference to the Romer I in an archived RCM discussion, and a
comment mentioned that the Holdridge/Romer accessories were available from
Travers Tool, but searching for them shows that they are no longer available
(but the Romer I price was $1349, (but I don't know if that price was for
this fixture, it seems unlikely)

The manufacturer was Holdridge Manufacturing Co., Inc. Gardena CA
90246-1726, but I haven't found any other info regarding the Romer I.

This company may have an old tradition of quality USA made tooling, but this
accessory appears to be a more recent type, made a bit more cheaply, from
off-the-shelf parts, and quite likely a spindle from a cheap 5C Chinese spin
index that's been fitted/resized for this product.

The cast crank/collet tightening handle is definitely of the quality found
on the cheap spin indexes (I'm certain of this because I bought one from
Enco several years ago about $28 at the time), but then it may not be the
original part since this accessory wasn't purchased new or NOS. The handle
does look just like the one in the photograph on the instruction sheet.

I noticed that the tapered roller bearing in the base is a Timken (Canada),
at least. I don't know about the bearings in the rotating section yet. I
looked, but didn't see any markings, and they appear to be shielded ball
bearing assemblies.
The setscrews all seem to be fractional/inch sizes.

As far as quality issues, the seller left a very nice 2mm Royal 5C collet
in the spindle. Since the collet isn't fully a combination of burrs and
nasty threads, I think it's a good indication that it's a genuine Royal
collet. I just don't know how important a 2mm size will be to my collet
collection. Anyways, I'll oil it and wrap/bag it for future use.

I have seen that some Holdridge machine accessories are for sale at various
tooling sources for fairly expensive prices, but I wasn't able to locate
much info about this particular grinding/indexing accessory.


A fairly basic instruction sheet came with it, so it's not a complete
mystery. There are a couple of illustrations/diagrams which show the initial
setup of the fixture in relationship to the T&C grinder wheel, assuming that
the T&C grinder has a finger for alignment.
The illustrations show a beveled grinding wheel being an example of the use
of the radius grinding fixture.


Overall, the majority of parts are anodized or plain, polished aluminum
(with that bright finish applied that looks like a silvery anodize).
The exceptions are the bearings, spindle and handle, the feed screws, and
misc hardware (setscrews) are steel. The threaded following/traveling nuts
for the feedscrews are brass.

The bottom section of the pivoting assembly has 2 counterbored holes for
SHCS to mount the accessory to a T&C grinder (or other useful point if not
using with a T&C grinder).

The raduised end of the base section contains a tapered roller bearing (the
Timken mentioned above).

There are 3 pieces of bare machined aluminum shaped like the letter F, that
act as limit stops for the amount of swing/pivot Left Limit - Center Stop -
and Right Limit (or CW Limit CCW limit instead of L - R Limits).

The next two sections are X feed and Y feed dovetailed slides made of
anodized aluminum. The gibs are very crudely formed strips of synthetic
material, maybe delrin or nylon.

The feed screws are left-hand common V threads (not acme or square threads)
and are both left open, exposing them to grinding dust. The diameters of the
screws seem undersize for 7/16" but the thread pitch is 20 TPI.


There was no trace of oil or lubrication on the dovetails or adjusting knob
shafts. Kinda strange, but oils would tend to make grinding swarf stick to
the moving parts.


I can see that this accessory needs some additional parts fitted to it to
give some of the parts some additional lifetime. Covers over the pivot
bearing and screws would keep swarf away from them, giving some additional
life.

The addition of dials on the X and Y feed knobs would give the operator some
idea of how far each slide is advancing, or to at least provide a means to
reset a slide to a previous position.


A better mechanical indexing method other than a plain pin passed through
the index plate and into a blind hole in the spin bearing housing.

The index plate has 12 holes, so 2, 3, and even-numbered flute cutters could
be indexed.


Centerline height... approx. 7.125"

Pivot swing 360 degrees

X travel (infeed toward the grinder wheel) several inches

Y travel (radius adjustment off-center) about an inch - choosing an extra
mounting position for the Y slide base would increase the maximum reach for
larger diameter cutters (or objects being ground).


With 5C collets, any size or shape within the 5C capacity could be held for
grinding.
An optional chucking method would be to use a 5C chuck instead of collets.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html

On Jan 8, 11:58*am, "Wild_Bill" wrote:
Maybe someone here in RCM has some experience with radius grinding fixtures,
and would like to share some information about using them to grind parts or
sharpening cutters.
...

Ball end mill sharpening instructions are at the end:
http://www.industrialtool.com.au/Bre...structions.pdf

jw

I can't find the operator instructions at that site. I can get a 2 page pdf
parts breakdown, but I couldn't get to anywhere that was specifically
following Breakdowns/Sharpeners shown in the URL.

Under the Parts & MSDS tab there is a listing for the E90i Operator
Instructions, but it's actually the 2 page parts breakdown list.

I also couldn't get the video to dislay, but I wouldn't expect it to be very
useful.

The problem is hack/spitWindows crapVista and it's security risk
countermeasures. With any normal OS, I could just click the link and view
the pdf, and choose to save it, or Save Target.

FWIW, the Holemaker Sharpener looks like a great machine, but limited in
it's use.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Jim Wilkins" wrote in message
...
On Jan 8, 11:58 am, "Wild_Bill" wrote:
Maybe someone here in RCM has some experience with radius grinding
fixtures,
and would like to share some information about using them to grind parts
or
sharpening cutters.
...

Ball end mill sharpening instructions are at the end:
http://www.industrialtool.com.au/Bre...structions.pdf

jw

On Fri, 9 Jan 2009 14:25:03 -0500, "Wild_Bill"
wrote:

snip
The problem is hack/spitWindows crapVista and it's security risk
countermeasures. With any normal OS, I could just click the link and view
the pdf, and choose to save it, or Save Target.

That doesn't sound like a Vista problem, more like
browser(shrug).

Give Opera a whirl. See:

http://www.opera.com/

I've been using it for ~10 years. Probably the best version
for you to try right now is 9.63 and get the standard (not
Classic) installer package for Windows. The old Classic
installer doesn't play so well with Vista.

You don't need to use its email or news group features.
Watch yourself too when installing and don't let it take
over as "default" for anything just yet. See if you can get
use to it first. It is HIGHLY customizable, if you don't
like something about the interface/looks most likely it can
be changed to your flavor.

It still uses ini files for most all of its settings, very
little use of the Windows registry. In other words, easy to
delete/get rid of if you so choose.

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

I expect that you're correct, Leon. It's just what was on this Compaq box
when I bought it, never expecting to still be using the hack/spitMS junk
that was in it.

I've got the stuff to put together another 3 GHz machine, just lacking the
gumption, due to my extreme prejudice of dealing with software of any kind.

If there was a computer built like an old mechanical typewriter or adding
machine, I'd be oiling and cleaning it regularly.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Leon Fisk" wrote in message
...
On Fri, 9 Jan 2009 14:25:03 -0500, "Wild_Bill"
wrote:

snip
The problem is hack/spitWindows crapVista and it's security risk
countermeasures. With any normal OS, I could just click the link and view
the pdf, and choose to save it, or Save Target.

That doesn't sound like a Vista problem, more like
browser(shrug).

Give Opera a whirl. See:

http://www.opera.com/

I've been using it for ~10 years. Probably the best version
for you to try right now is 9.63 and get the standard (not
Classic) installer package for Windows. The old Classic
installer doesn't play so well with Vista.

You don't need to use its email or news group features.
Watch yourself too when installing and don't let it take
over as "default" for anything just yet. See if you can get
use to it first. It is HIGHLY customizable, if you don't
like something about the interface/looks most likely it can
be changed to your flavor.

It still uses ini files for most all of its settings, very
little use of the Windows registry. In other words, easy to
delete/get rid of if you so choose.

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

On 2009-01-08, Wild_Bill wrote:
Maybe someone here in RCM has some experience with radius grinding fixtures,
and would like to share some information about using them to grind parts or
sharpening cutters.

I picked this radius grinding/indexing accessory up on eBay. I had no
previous knowlege of the Holdridge or Romer names or tooling.

It's described as being a Romer I Radial Grinding Fixture for universal (T &
C) tool and cutter grinders which I don't presently own) but I was curious
about it's versatility.

This is a radius grinding spin index-type accessory, not a Holdridge ball
turning accessory for a lathe toolpost.

http://www.kwagmire.com/tools/Radius...er/romer1.html

Do you have any old badly chipped tip end mills which you would
like to turn into either ball end mills or radiusing cutters?

That is what this does with the aid of a T&C grinder.

I doubt that it would be much use for indexing workpieces on a
mill. Not strong enough.

And it may well have a fitting for feeding air into the sleeve
around the spindle, to turn it into an air bearing. This is common on
the ones for sharpening the side edges of an end mill -- slide it along,
and let it ride on the finger to keep the flute at the right height.

Enjoy,
DoN.

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

There is no air bearing, DoN.. just ball bearings for rotation (no sliding),
and definitely not built for indexing on a mill.

Making ball endmills is probably the best use for it, and that would
probably be interesting to do.
It might be useful for grinding lathe cutting tools with convex or concave
shapes.

Perfectly radiused ends on chuck key handles, heh. Gotta go write up a
contract proposal for Jacobs.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"DoN. Nichols" wrote in message
...
On 2009-01-08, Wild_Bill wrote:
Maybe someone here in RCM has some experience with radius grinding
fixtures,
and would like to share some information about using them to grind parts
or
sharpening cutters.

http://www.kwagmire.com/tools/Radius...er/romer1.html

Do you have any old badly chipped tip end mills which you would
like to turn into either ball end mills or radiusing cutters?

That is what this does with the aid of a T&C grinder.

I doubt that it would be much use for indexing workpieces on a
mill. Not strong enough.

And it may well have a fitting for feeding air into the sleeve
around the spindle, to turn it into an air bearing. This is common on
the ones for sharpening the side edges of an end mill -- slide it along,
and let it ride on the finger to keep the flute at the right height.

Enjoy,
DoN.

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

On 2009-01-10, Wild_Bill wrote:
I expect that you're correct, Leon. It's just what was on this Compaq box
when I bought it, never expecting to still be using the hack/spitMS junk
that was in it.

I've got the stuff to put together another 3 GHz machine, just lacking the
gumption, due to my extreme prejudice of dealing with software of any kind.

If there was a computer built like an old mechanical typewriter or adding
machine, I'd be oiling and cleaning it regularly.

There is -- the Babbage "analytical engine". They weren't
able to complete it in his lifetime, but they have since done so.

And yes -- It would love to be oiled.

Enjoy,
DoN.

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

On 2009-01-10, Wild_Bill wrote:
There is no air bearing, DoN.. just ball bearings for rotation (no sliding),
and definitely not built for indexing on a mill.

Making ball endmills is probably the best use for it, and that would
probably be interesting to do.

Indeed so -- for a while at least.

It might be useful for grinding lathe cutting tools with convex or concave
shapes.

You would need a square collet of the right size (of course),
and the ability to raise or lower the grinding head to the right
position to match the needed relief on the cutter. That would be a nice
secondary use for it.

Perfectly radiused ends on chuck key handles, heh. Gotta go write up a
contract proposal for Jacobs.

Only if you can talk them into making their key handles
seriously hardened. Mild steel is a bit of a problem with a grinder
like that -- unless you can find the right stones in the right shape for
the material.

Enjoy,
DoN.

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

What you mentioned about the needed difference in center height for grinding
radiused lathe cutting tools is correct, DoN.
Yep, square collets for holding lathe tools.

That's what I think is a bit strange about this grinder accessory to begin
with. I don't have a T&C grinder, but I don' recall seeing any with wheel
height adjustments.

The operating instruction sheets have a couple of diagrams (not photos of an
actual installation on a T&C grinder), indicating the need to have the
grinder wheel center line below the center line of the cutter being
sharpened.
A difference in height would also be required for relief angles on ball
endmill flutes, so I suppose that the maker is suggesting (not specifically
stating) that some shims or special fitting would be required for
installation.
As I pointed out in the description, I didn't purchase this new, but
instead, I got this from a seller that said it was a customer return. So it
may have originally had other mounting parts with it when new.

The instruction sheets just state; for use with all universal T&C grinders.
I haven't decided what I'll use this radius accessory for yet, or what type
of grinder I might use it with.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"DoN. Nichols" wrote in message
...
On 2009-01-10, Wild_Bill wrote:
There is no air bearing, DoN.. just ball bearings for rotation (no
sliding),
and definitely not built for indexing on a mill.

Making ball endmills is probably the best use for it, and that would
probably be interesting to do.

Indeed so -- for a while at least.

It might be useful for grinding lathe cutting tools with convex or
concave
shapes.

You would need a square collet of the right size (of course),
and the ability to raise or lower the grinding head to the right
position to match the needed relief on the cutter. That would be a nice
secondary use for it.

Perfectly radiused ends on chuck key handles, heh. Gotta go write up a
contract proposal for Jacobs.

Only if you can talk them into making their key handles
seriously hardened. Mild steel is a bit of a problem with a grinder
like that -- unless you can find the right stones in the right shape for
the material.

Enjoy,
DoN.

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

On Jan 11, 4:07*am, "Wild_Bill" wrote:
What you mentioned about the needed difference in center height for grinding
radiused lathe cutting tools is correct, DoN.
Yep, square collets for holding lathe tools.

The diagonal of 1/4" is very close to 9mm. You can use a ball-nosed
end mill in a boring bar holder to turn an inside radius, or grind the
tool for an outside radius with a tapered die grinder stone held
vertically. This gives a good smooth-cutting finish if not an exact
radius.

That's what I think is a bit strange about this grinder accessory to begin
with. I don't have a T&C grinder, but I don' recall seeing any with wheel
height adjustments.

The Delta Milwaukee Toolmaker's head raises and swivels on a round
column. I think proper T&C grinders have a knee like a milling
machine.

The instruction sheets just state; for use with all universal T&C grinders.
I haven't decided what I'll use this radius accessory for yet, or what type
of grinder I might use it with.
WB

Any surface grinder should work. I haven't been able to free the
spindle adapter on my Toolmaker to swap dressed wheels, so I sharpen
tools underneath the wheel like a normal surface grinder. The homemade
horizontal tooth stop is a short piece of old hacksaw blade, offset to
5 degrees with a protractor. If the job is worth redressing wheels I
switch to a dish or cup wheel and swivel the head enough to clear the
dead centers. You could do that with a real surface grinder to sharpen
a ball end mill since the fixture only has to swivel 90 degrees and
won't hit the other side of the dish.

A small radius or bevel on the corners of an end mill makes it stay
sharp much longer. I use the back relief setting on the end mill
fixture to grind a flat 30 degree bevel. A small radius would look
better and not leave a stress riser on the work.

The Toolmaker is like a Shopsmith or Smithy, a multipurpose
combination that will do many different jobs poorly. In addition mine
is very worn, but it still sharpens tools well enough for my home
shop. Tool making is an art I'm a long way from mastering.

Jim Wilkins

Thanks for the additional info, Jim. I had read that grinding the sharp
points off of endmills would keep them sharper longer, but haven't tried it
yet. The idea of radiused cuts sounds very beneficial where a 90 degree
corner isn't required.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Jim Wilkins" wrote in message
...

The diagonal of 1/4" is very close to 9mm. You can use a ball-nosed
end mill in a boring bar holder to turn an inside radius, or grind the
tool for an outside radius with a tapered die grinder stone held
vertically. This gives a good smooth-cutting finish if not an exact
radius.

The Delta Milwaukee Toolmaker's head raises and swivels on a round
column. I think proper T&C grinders have a knee like a milling
machine.

Any surface grinder should work. I haven't been able to free the
spindle adapter on my Toolmaker to swap dressed wheels, so I sharpen
tools underneath the wheel like a normal surface grinder. The homemade
horizontal tooth stop is a short piece of old hacksaw blade, offset to
5 degrees with a protractor. If the job is worth redressing wheels I
switch to a dish or cup wheel and swivel the head enough to clear the
dead centers. You could do that with a real surface grinder to sharpen
a ball end mill since the fixture only has to swivel 90 degrees and
won't hit the other side of the dish.

A small radius or bevel on the corners of an end mill makes it stay
sharp much longer. I use the back relief setting on the end mill
fixture to grind a flat 30 degree bevel. A small radius would look
better and not leave a stress riser on the work.

The Toolmaker is like a Shopsmith or Smithy, a multipurpose
combination that will do many different jobs poorly. In addition mine
is very worn, but it still sharpens tools well enough for my home
shop. Tool making is an art I'm a long way from mastering.

Jim Wilkins