I've got a bunch that have chipped tips on the flutes , and I
guess it's time I learned to sharpen them instead of tossing them and
buying more .I've poked around a little and found a design for a fixture
using 5C collets that I can build with tooling I have on hand . I do
have a question about using my mill to grind these . It doesn't spin as
fast a a real grinder , about 1800 RPM tops IIRC . I'm looking for
suggestions what type of wheel I need . Probably a cup wheel since the
end mill will mount with the tip up .

--
Snag
"You can lead a dummy to facts
but you can't make him think."

"Snag" wrote in message news:tmugmi$13efh$1@dont-email.me...

I've got a bunch that have chipped tips on the flutes , and I
guess it's time I learned to sharpen them instead of tossing them and
buying more .I've poked around a little and found a design for a fixture
using 5C collets that I can build with tooling I have on hand . I do
have a question about using my mill to grind these . It doesn't spin as
fast a a real grinder , about 1800 RPM tops IIRC . I'm looking for
suggestions what type of wheel I need . Probably a cup wheel since the
end mill will mount with the tip up .
Snag

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

This type of fixture works well enough for me, on my ancient $100 surface
grinder.
https://www.grizzly.com/products/grizzly-end-mill-grinding-fixture/g9887
I have the Enco version with 24 click stops, no dial or lock screw. The base
was cut square and the relief angle is in the mounting hole for the ring
that retains the collet holder. If I'd tried to make it I might have had
trouble matching the collet taper, the rest is pretty simple and the tilt
angles shouldn't need to be exact, eyeball alignment in the collet and on
the grinder mag chuck is good enough to make an endmill cut well. I did
machine another collet closer nut that accepts flanged bushings to center an
S&D drill bit, etc.

It isn't obvious that the end cutting edges angle in slightly toward the
center. If you are set on making your own I can measure the collet holder's
lengthwise and sideways tilt angles on mine.

In addition to sharpening the ends normally it can grind worn tips into a 30
degree bevel to cut sideways without dulling the spiral edges. I have one
old 1/2" 4-flute that I grind that way and use for roughing, to save the
other endmills for finishing. Another scheme to preserve the spiral edges is
to rough with plunge cuts which dull only the end edges that I can easily
regrind.

I also have a fixture like this to sharpen the spiral edges:
https://www.shars.com/end-mill-cutter-and-sharpener
It's quite fussy to set up and use, and it reduces the diameter which can be
useful to cut a slot to 0.500" (with multiple passes or another new endmill)
instead of slightly larger from deflection, but is otherwise a nuisance
since they look the same.
I made it more rigid by removing the tilt mechanism that would swing the
endmill into or away from a cup wheel, since I grind on the top with a
normal 6" wheel.

On 12/9/2022 6:28 AM, Jim Wilkins wrote:
> "Snag"  wrote in message news:tmugmi$13efh$1@dont-email.me...
>
>   I've got a bunch that have chipped tips on the flutes , and I
>  guess it's time I learned to sharpen them instead of tossing them and
> buying more .I've poked around a little and found a design for a fixture
>  using 5C collets that I can build with tooling I have on hand . I do
> have a question about using my mill to grind these . It doesn't spin as
> fast a a real grinder , about 1800 RPM tops IIRC . I'm looking for
> suggestions what type of wheel I need . Probably a cup wheel since the
> end mill will mount with the tip up .
> Snag
>
> ---------------------
>
> This type of fixture works well enough for me, on my ancient $100
> surface grinder.
> https://www.grizzly.com/products/grizzly-end-mill-grinding-fixture/g9887
> I have the Enco version with 24 click stops, no dial or lock screw. The
> base was cut square and the relief angle is in the mounting hole for the
> ring that retains the collet holder. If I'd tried to make it I might
> have had trouble matching the collet taper, the rest is pretty simple
> and the tilt angles shouldn't need to be exact, eyeball alignment in the
> collet and on the grinder mag chuck is good enough to make an endmill
> cut well. I did machine another collet closer nut that accepts flanged
> bushings to center an S&D drill bit, etc.
>
> It isn't obvious that the end cutting edges angle in slightly toward the
> center. If you are set on making your own I can measure the collet
> holder's lengthwise and sideways tilt angles on mine.
>
> In addition to sharpening the ends normally it can grind worn tips into
> a 30 degree bevel to cut sideways without dulling the spiral edges. I
> have one old 1/2" 4-flute that I grind that way and use for roughing, to
> save the other endmills for finishing. Another scheme to preserve the
> spiral edges is to rough with plunge cuts which dull only the end edges
> that I can easily regrind.
>
> I also have a fixture like this to sharpen the spiral edges:
> https://www.shars.com/end-mill-cutter-and-sharpener
> It's quite fussy to set up and use, and it reduces the diameter which
> can be useful to cut a slot to 0.500" (with multiple passes or another
> new endmill) instead of slightly larger from deflection, but is
> otherwise a nuisance since they look the same.
> I made it more rigid by removing the tilt mechanism that would swing the
> endmill into or away from a cup wheel, since I grind on the top with a
> normal 6" wheel.
>

The Griz unit is the one I plan to try to duplicate . The shars unit
is discontinued but I seldom dull the sides . Knowing the angles
involved would be a big help ...
I'm still wondering what type of grinding wheel I need for the RPM's
my mill has .
--
Snag
"You can lead a dummy to facts
but you can't make him think."

"Jim Wilkins" wrote in message news:tmv9mu$157ci$1@dont-email.me...
....
In addition to sharpening the ends normally it can grind worn tips into a 30
degree bevel to cut sideways without dulling the spiral edges.
....

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

If that isn't clear, the fixture is tilted onto the 25 degree (I measured
it) angled face and the chipped end mill tip is ground back at that angle
like the cutting edge of a drill bit. It will cut as long as the least
chipped corner has been sharpened, and eventually regrinding may restore
others. You can grind a badly chipped one back to square with a bench or
angle grinder and restore the cutting edge geometry with the fixture. 4
flute endmills can be salvaged although they are unlikely to remain center
cutting, 2 flute ones are easier.

Based on my mill's somewhat limited rigidity I grind the dull point back
about 0.025" or less lengthwise, leaving at least half the diameter cutting
flat, and alternate between regrinding it square or beveled. Both edge faces
wear from roughing by plunge cuts. The beveled cutting edges seem much less
vulnerable to chipping in mystery metal with hard spots.

I would be extremely careful to keep grit off the exposed ways of a mill.
The ways of a surface grinder are shielded.

On 12/9/2022 8:01 AM, Jim Wilkins wrote:
> "Jim Wilkins"  wrote in message news:tmv9mu$157ci$1@dont-email.me...
> ...
> In addition to sharpening the ends normally it can grind worn tips into
> a 30
> degree bevel to cut sideways without dulling the spiral edges.
> ...
>
> ----------------
>
> If that isn't clear, the fixture is tilted onto the 25 degree (I
> measured it) angled face and the chipped end mill tip is ground back at
> that angle like the cutting edge of a drill bit. It will cut as long as
> the least chipped corner has been sharpened, and eventually regrinding
> may restore others. You can grind a badly chipped one back to square
> with a bench or angle grinder and restore the cutting edge geometry with
> the fixture. 4 flute endmills can be salvaged although they are unlikely
> to remain center cutting, 2 flute ones are easier.
>
> Based on my mill's somewhat limited rigidity I grind the dull point back
> about 0.025" or less lengthwise, leaving at least half the diameter
> cutting flat, and alternate between regrinding it square or beveled.
> Both edge faces wear from roughing by plunge cuts. The beveled cutting
> edges seem much less vulnerable to chipping in mystery metal with hard
> spots.
>

> I would be extremely careful to keep grit off the exposed ways of a
> mill. The ways of a surface grinder are shielded.
>

That's what old sheets are for ... OK , so after watching some Joe Py
video I went ahead and ordered a 6" bonded grit saw blade sharpening
wheel . It should work well as long as I don't get too frisky with feed
rates . This project will go on the back burner for now , got other
stuff that's more pressing - like getting the new gears installed in my
truck axle . I can't finish carb/timing/etc tuning until that's done .
And I can't do that until I get my neighbor's 4X4 UTV finished . Maybe
today on that one , almost finished reassembly after replacing a set of
bevel gears deep inside the guts . Had to split the cases to get to the
damaged gears .
--
Snag
"You can lead a dummy to facts
but you can't make him think."

On 12/8/2022 10:22 PM, Snag wrote:
>   I've got a bunch that have chipped tips on the flutes , and I
>  guess it's time I learned to sharpen them instead of tossing them and
> buying more .I've poked around a little and found a design for a fixture
>  using 5C collets that I can build with tooling I have on hand . I do
> have a question about using my mill to grind these . It doesn't spin as
> fast a a real grinder , about 1800 RPM tops IIRC . I'm looking for
> suggestions what type of wheel I need . Probably a cup wheel since the
> end mill will mount with the tip up .
>

Since I do mostly CNC its not worth it to me generally, but I do have a
diamond cut off wheel for the TC grinder so I can lop off the chowdered
tips of a carbide mill and use it strictly for side milling. I don't
have much in the way of HSS mills. Most of them are still on the floor
where I threw that harbor Freight box six months ago.

That being said I have purchased resharpened a couple times when I
needed a particular geometry for a single job and didn't want to spend a
lot on it. There is a sharpening outfit in Phoenix that used to have
tons of resharpened mills on Ebay pretty cheap.

--
This email has been checked for viruses by AVG antivirus software.
www.avg.com

Projects, projects, ...

AFAICT with limited equipment the collet tilt angles are 5 degrees toward
the beveled end and 2 degrees to the left with the bevel toward you (or me).
At least those angle blocks visually match it to a square. I confirmed that
the bevel is 25 degrees from the base.

"Snag" wrote in message news:tmvdsa$15i01$1@dont-email.me...

I'm still wondering what type of grinding wheel I need for the RPM's
my mill has .

----------

I doubt that it matters all that much if you aren't in production, grinding
works down to hand honing speed.
https://www.ebay.com/b/Crank-Grinder-In-other-Collectible-Tools/1461/bn_7022913747

The normal speed of my surface grinder burns carbon steel jointer blades
unless I take -very- light passes.

On 12/9/2022 11:25 AM, Jim Wilkins wrote:
> Projects, projects, ...
>
> AFAICT with limited equipment the collet tilt angles are 5 degrees
> toward the beveled end and 2 degrees to the left with the bevel toward
> you (or me). At least those angle blocks visually match it to a square.
> I confirmed that the bevel is 25 degrees from the base.
>
>
>

Thanks , those are pretty close to the numbers I expected . One more
good day on the neighbor's machine should see it back in running shape ,
the motor's ready to drop in now .
I originally told the neighbor that I would do his after I finished
the truck ... I relented and moved it up because his wife was making him
miserable over it . She's one of those "corporate movers and shakers" .
I'm sure glad I married a "simple country girl" !
--
Snag
"You can lead a dummy to facts
but you can't make him think."

"Snag" wrote in message news:tn07ss$1asq8$1@dont-email.me...

Thanks , those are pretty close to the numbers I expected . One more
good day on the neighbor's machine should see it back in running shape ,
the motor's ready to drop in now .
I originally told the neighbor that I would do his after I finished
the truck ... I relented and moved it up because his wife was making him
miserable over it . She's one of those "corporate movers and shakers" .
I'm sure glad I married a "simple country girl" !
Snag

-------------------
My day's project was lost to helping an elderly neighbor too. Everything
went wrong, and it's reassuring that in my mid 70's I can still diagnose and
fix problems quickly.

On 12/10/2022 5:22 PM, Jim Wilkins wrote:
> "Snag"  wrote in message news:tn07ss$1asq8$1@dont-email.me...
>
> Thanks , those are pretty close to the numbers I expected . One more
> good day on the neighbor's machine should see it back in running shape ,
> the motor's ready to drop in now .
>   I originally told the neighbor that I would do his after I finished
> the truck ... I relented and moved it up because his wife was making him
> miserable over it . She's one of those "corporate movers and shakers" .
> I'm sure glad I married a "simple country girl" !
> Snag
>
> ------------------- My day's project was lost to helping an elderly
> neighbor too. Everything went wrong, and it's reassuring that in my mid
> 70's I can still diagnose and fix problems quickly.
>

Kids now days , if they can't read the problem off a computer screen
they're totally lost . Remember Gus from Popular Mechanics (IIRC) back
in the 50's-60's ? His column taught me to diagnose a burned exhaust
valve by sticking a strip of paper to the end of the exhaust pipe with
bubblegum ...
--
Snag
"You can lead a dummy to facts
but you can't make him think."

On 12/10/2022 5:41 PM, Snag wrote:
> On 12/10/2022 5:22 PM, Jim Wilkins wrote:
>> "Snag"  wrote in message news:tn07ss$1asq8$1@dont-email.me...
>>
>> Thanks , those are pretty close to the numbers I expected . One more
>> good day on the neighbor's machine should see it back in running shape ,
>> the motor's ready to drop in now .
>>    I originally told the neighbor that I would do his after I finished
>> the truck ... I relented and moved it up because his wife was making him
>> miserable over it . She's one of those "corporate movers and shakers" .
>> I'm sure glad I married a "simple country girl" !
>> Snag
>>
>> ------------------- My day's project was lost to helping an elderly
>> neighbor too. Everything went wrong, and it's reassuring that in my
>> mid 70's I can still diagnose and fix problems quickly.
>>
>
>   Kids now days , if they can't read the problem off a computer screen
> they're totally lost . Remember Gus from Popular Mechanics (IIRC) back
> in the 50's-60's ? His column taught me to diagnose a burned exhaust
> valve by sticking a strip of paper to the end of the exhaust pipe with
> bubblegum ...

Speaking of off the computer screen. There is a YouTuber who uses his
mill fairly often as a grinder you might find interesting. Its not
typically a "grinding" video, but instead one part of a project. He did
a fair amount of grinding in a video about making a grinder vise
(screwless vise). In a more recent video he touched on mill grinding
when making a case hardened gear. He also does a bit of case hardening.

Artisan Makes

Aside: I currently use modified grinder vises as my primary fixturing
attachment on 4 mills because they take up less space for their range
than a mill vise, and they are more flexible than a fixture plate. (I
Use fixture plates too. Some mount in the vises as needed.)

Back on topic: I suppose I should have put this out there sooner. There
are two answers that come to mind for me about your concerns for speed.
(1) A larger wheel gives more surface speed. (2) Grinding slower works
fine. Its just slower. For example a Tormec knife grinder is an order
of magnitude slower than a bench grinder or most other machine shop
grinding machines.

--
This email has been checked for viruses by AVG antivirus software.
www.avg.com

On 12/11/2022 11:39 AM, Bob La Londe wrote:
> On 12/10/2022 5:41 PM, Snag wrote:
>> On 12/10/2022 5:22 PM, Jim Wilkins wrote:
>>> "Snag"  wrote in message news:tn07ss$1asq8$1@dont-email.me...
>>>
>>> Thanks , those are pretty close to the numbers I expected . One more
>>> good day on the neighbor's machine should see it back in running shape ,
>>> the motor's ready to drop in now .
>>>    I originally told the neighbor that I would do his after I finished
>>> the truck ... I relented and moved it up because his wife was making him
>>> miserable over it . She's one of those "corporate movers and shakers" .
>>> I'm sure glad I married a "simple country girl" !
>>> Snag
>>>
>>> ------------------- My day's project was lost to helping an elderly
>>> neighbor too. Everything went wrong, and it's reassuring that in my
>>> mid 70's I can still diagnose and fix problems quickly.
>>>
>>
>>    Kids now days , if they can't read the problem off a computer
>> screen they're totally lost . Remember Gus from Popular Mechanics
>> (IIRC) back in the 50's-60's ? His column taught me to diagnose a
>> burned exhaust valve by sticking a strip of paper to the end of the
>> exhaust pipe with bubblegum ...
>
>
> Speaking of off the computer screen.  There is a YouTuber who uses his
> mill fairly often as a grinder you might find interesting. Its not
> typically a "grinding" video, but instead one part of a project.  He did
> a fair amount of grinding in a video about making a grinder vise
> (screwless vise).  In a more recent video he touched on mill grinding
> when making a case hardened gear.  He also does a bit of case hardening.
>
> Artisan Makes
>
> Aside:  I currently use modified grinder vises as my primary fixturing
> attachment on 4 mills because they take up less space for their range
> than a mill vise, and they are more flexible than a fixture plate.  (I
> Use fixture plates too.  Some mount in the vises as needed.)
>
> Back on topic: I suppose I should have put this out there sooner.  There
> are two answers that come to mind for me about your concerns for speed.
> (1) A larger wheel gives more surface speed.  (2) Grinding slower works
> fine.  Its just slower.  For example a Tormec knife grinder is an order
> of magnitude slower than a bench grinder or most other machine shop
> grinding machines.
>
>
>

I chose the 6" saw grinder wheel partly because it has 1 1/2 times
the surface speed of a 4" cup . And partly because it was fairly cheap ,
and partly because of the profile . With the right setup I can gash with
it too .
I've been pondering the base for the fixture to mount the end mills .
I think I'll make the bottom angles and have the sides and ends square
with them . Then put the 2° bevel on top with the thru hole
perpendicular to the top . Just seems like the easiest way to me .
--
Snag
"You can lead a dummy to facts
but you can't make him think."

"Snag" wrote in message news:tn5940$2098c$1@dont-email.me...
...
I've been pondering the base for the fixture to mount the end mills .
I think I'll make the bottom angles and have the sides and ends square
with them . Then put the 2° bevel on top with the thru hole
perpendicular to the top . Just seems like the easiest way to me .
Snag

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

I set the end mill fixture on my mill with the collet upright, 1/2" rod in
the fixture and spindle collets, raised the table to contact with the back
right corner, then pushed a 1/4" thick bar into the wedge space underneath
from the front (bevel) side. The bar intersects the left side 2.05" from the
back and the right side 2.95" from the back. A squared rectangular base
block could be clamped to a mill table or lathe faceplate this way and bored
straight in to get both 2 and 5 degree angles easily.

I might attach the 1/4" angled spacer with countersunk screws to reduce
fumbling and let the setup be accurately repeated later.
jsw

On 12/11/2022 5:04 PM, Jim Wilkins wrote:
> "Snag"  wrote in message news:tn5940$2098c$1@dont-email.me...
> ..
>   I've been pondering the base for the fixture to mount the end mills .
> I think I'll make the bottom angles and have the sides and ends square
> with them . Then put the 2° bevel on top with the thru hole
> perpendicular to the top . Just seems like the easiest way to me .
> Snag
>
> ---------------------
>
> I set the end mill fixture on my mill with the collet upright, 1/2" rod
> in the fixture and spindle collets, raised the table to contact with the
> back right corner, then pushed a 1/4" thick bar into the wedge space
> underneath from the front (bevel) side. The bar intersects the left side
> 2.05" from the back and the right side 2.95" from the back. A squared
> rectangular base block could be clamped to a mill table or lathe
> faceplate this way and bored straight in to get both 2 and 5 degree
> angles easily.
>
> I might attach the 1/4" angled spacer with countersunk screws to reduce
> fumbling and let the setup be accurately repeated later.
> jsw
>

I'm going to have to take a minute to digest that ... OK , if I'm
understanding this correctly I'll only have to cut one angle on the
bottom , the other two will be produced by the way the hole for the
collet is bored in the block - 2° tilt to the rear , 5° to the right .
If I put a couple of degree angle on the left end I can set the fixture
up to do the gash with the end mill horizontal/angled slightly down .
It's been a long day , and I do enjoy a few shots of sour mash in the
evening . It's been a gloomy day here , fine drizzle most of the day .
The dog and I both hate being cooped up inside all day .
--
Snag
"You can lead a dummy to facts
but you can't make him think."

"Snag" wrote in message news:tn6b20$25j6e$1@dont-email.me...

On 12/11/2022 5:04 PM, Jim Wilkins wrote:
> "Snag" wrote in message news:tn5940$2098c$1@dont-email.me...
> ..
> I've been pondering the base for the fixture to mount the end mills .
> I think I'll make the bottom angles and have the sides and ends square
> with them . Then put the 2° bevel on top with the thru hole
> perpendicular to the top . Just seems like the easiest way to me .
> Snag
>
> ---------------------
>
> I set the end mill fixture on my mill with the collet upright, 1/2" rod in
> the fixture and spindle collets, raised the table to contact with the back
> right corner, then pushed a 1/4" thick bar into the wedge space underneath
> from the front (bevel) side. The bar intersects the left side 2.05" from
> the back and the right side 2.95" from the back. A squared rectangular
> base block could be clamped to a mill table or lathe faceplate this way
> and bored straight in to get both 2 and 5 degree angles easily.
>
> I might attach the 1/4" angled spacer with countersunk screws to reduce
> fumbling and let the setup be accurately repeated later.
> jsw
>

I'm going to have to take a minute to digest that ... OK , if I'm
understanding this correctly I'll only have to cut one angle on the
bottom , the other two will be produced by the way the hole for the
collet is bored in the block - 2° tilt to the rear , 5° to the right .
If I put a couple of degree angle on the left end I can set the fixture
up to do the gash with the end mill horizontal/angled slightly down .
It's been a long day , and I do enjoy a few shots of sour mash in the
evening . It's been a gloomy day here , fine drizzle most of the day .
The dog and I both hate being cooped up inside all day .
Snag

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

Yes, the angled 1/4" spacer tilts the base block to the 2 degree sideways
and 5 degree lengthwise angles, or at least it will duplicate the angles of
mine with only simple length measurements. If you fit it to the base block
before milling the 25 degree bevel you can screw it down in the area that
will be removed.

However it won't allow very secure clamping, so if you want to go that way
I'll have to find out how far you can rough drill and bore the collet holder
recess with the base block clamped squarely and solidly in a milling vise.
Then you'll have to re-locate the center in the rough hole when it's clamped
at the angle, perhaps with a sheet metal template of the base with the
center punched. You could clamp stuff around it to help keep it from
twisting out of place from the cutting force.

You only have to mill the 25° (degree) bevel which can be done with the base
block clamped solidly in the vise. Do you have an angle block set? Mine is a
much cheaper Enco version of this:
https://www.mscdirect.com/product/details/01718360

Before MSC bought them, Enco had a retail store in southern NH (no sales
tax) so I stocked up on everything I might need.
jsw

"Jim Wilkins" wrote in message news:tn77jp$27nid$1@dont-email.me...

I'm going to have to take a minute to digest that ... OK , if I'm
understanding this correctly I'll only have to cut one angle on the
bottom , the other two will be produced by the way the hole for the
collet is bored in the block - 2° tilt to the rear , 5° to the right .
If I put a couple of degree angle on the left end I can set the fixture
up to do the gash with the end mill horizontal/angled slightly down .
Snag

-------------
I don't understand the last sentence.

Facing the base bevel, the collet tilts 5 degrees toward you and 2 degrees
to the left. Conversely the way I have it in the mill with the collet
vertical, the base tilts up toward me and on the left side, which is why the
1/4" parallel jammed under it is at an angle. The easy way to copy that
angle is to duplicate the distances from the bar to the back of the base
block on both sides, assuming you make the block the same width as mine,
2.5053".

The 5 degree tilt provides back relief to the cutting edge, the 2 degree
dishes the edges inward slightly so only the tips cut, even as they dull. I
don't think either angle is critical, recommendations I've seen for back
relief are a range that almost always includes 5 degrees. Likewise grinding
while on the 25 degree base bevel merely removes the bulk of flute material
behind the cutting edge, or balances it if you ground most away faster on a
bench grinder. Surface grinder wheels can explode if you try to force too
heavy a cut, I've been nearby on another machine when a kid did that.

I think you can make all cuts with the end mill or boring head vertical, and
do most of the machining on the base with it square or single-angled in the
vise. On my mill the head can be tilted and swiveled to bore the angled
collet recess directly, with the base in the milling vise, though squaring
(tramming) it up again afterwards is a lot of trouble since the round ram
shifts when the clamps are tightened.
http://www.lathes.co.uk/clausing%20vertical/img0.gif

I took my endmill fixture apart to measure the stock size you'd need to copy
it. This is the same design:
https://www.penntoolco.com/precise-end-mill-grinding-fixture-5-c-collet-capacity-emf-100/

The base is 1" thick by 2.5" wide by 4.5" long.
The collet holder is rod stock at least 1.85" diameter by 2.75" long.
Its retaining ring is 2.375" diameter by 12mm thick (plate stock?). It fits
into the angled bore in the base block.
The collet closer nut is a little under 1.5" diameter.
The 3 indexing balls are .187" diameter, with similar sized compression
springs.

The collet holder has a circle of 24 indexing dimples in the flanged lower
end.

The holes for the index balls and springs were drilled while the block was
tilted, so you may have to center it on a rotary index table with the 1/4"
spacer in place. Likewise the 3 screws that attach the collet retaining ring
were angled through the base, thus square into the ring, and countersunk at
the angle from the bottom side, which may be tricky.

The Grizzly G9887 is on sale for $61.15.

On 12/12/2022 9:16 AM, Jim Wilkins wrote:
> "Jim Wilkins"  wrote in message news:tn77jp$27nid$1@dont-email.me...
>
>   I'm going to have to take a minute to digest that ... OK , if I'm
> understanding this correctly I'll only have to cut one angle on the
> bottom , the other two will be produced by the way the hole for the
> collet is bored in the block - 2° tilt to the rear , 5° to the right .
> If I put a couple of degree angle on the left end I can set the fixture
> up to do the gash with the end mill horizontal/angled slightly down .
> Snag
>
> -------------
> I don't understand the last sentence.
>

I was talking about cutting the end gash with the end mill held
horizontal and using the edge of the grinding wheel . I've got this
figured out now . I planned on making this with a screw lock and 12
dimples in the collet sleeve to lock the setting . For now though it's
on the back burner .

--
Snag
"You can lead a dummy to facts
but you can't make him think."

"Snag" wrote in message news:tn7sid$29fcg$1@dont-email.me...

I was talking about cutting the end gash with the end mill held
horizontal and using the edge of the grinding wheel . I've got this
figured out now . I planned on making this with a screw lock and 12
dimples in the collet sleeve to lock the setting . For now though it's
on the back burner .
Snag

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

The screw lock style should be less demanding to machine, on mine the three
spring-loaded balls have to all engage the dimples equally, but I can turn
it with one hand that is on the far side of the fixture from the spinning
wheel, and count the clicks. With the single screw lock a slight indexing
error won't matter.

Actually you need only as many dimples as you have flutes to sharpen, which
for me is 8 on shell mills.

On 12/13/2022 8:31 AM, Jim Wilkins wrote:
> "Snag"  wrote in message news:tn7sid$29fcg$1@dont-email.me...
>
>  I was talking about cutting the end gash with the end mill held
> horizontal and using the edge of the grinding wheel . I've got this
> figured out now . I planned on making this with a screw lock and 12
> dimples in the collet sleeve to lock the setting . For now though it's
> on the back burner .
> Snag
>
> --------------
>
> The screw lock style should be less demanding to machine, on mine the
> three spring-loaded balls have to all engage the dimples equally, but I
> can turn it with one hand that is on the far side of the fixture from
> the spinning wheel, and count the clicks. With the single screw lock a
> slight indexing error won't matter.
>
> Actually you need only as many dimples as you have flutes to sharpen,
> which for me is 8 on shell mills.
>

I was thinking 12 since it's evenly divisible by both 3 and 4 and I
have 3 and 4 flute end mills - and a rotary table (7.5 turns per 30° at
90:1) . It's raining here again and I have no other projects ... except
the neighbor's SxS UTV , and I ain't working on it in the rain . So a
little while ago I started roughing stock for this project . Yesterday
it wasn't raining , but I wanted to watch the guys installing my new
septic tank . Concrete this time , the last one was steel and only
lasted about 18-19 years .
--
Snag
"You can lead a dummy to facts
but you can't make him think."

"Snag" wrote in message news:tnae60$2ij1f$1@dont-email.me...

I was thinking 12 since it's evenly divisible by both 3 and 4 and I
have 3 and 4 flute end mills - and a rotary table (7.5 turns per 30° at
90:1) . It's raining here again and I have no other projects ... except
the neighbor's SxS UTV , and I ain't working on it in the rain . So a
little while ago I started roughing stock for this project . Yesterday
it wasn't raining , but I wanted to watch the guys installing my new
septic tank . Concrete this time , the last one was steel and only
lasted about 18-19 years .
Snag
---------------------

Manual indexing is a tedious and error-prone task. You can double-check by
setting dividers to the spacing of the first two holes and using them to
confirm the next drilling location if you are interrupted. Any error should
be large, a whole or half turn. My last dividing job was cutting a 68 tooth
gear and there were issues... The one before that was 13, to spline a shaft
for a motorcycle drive sprocket.

That storm may be heavy snow or ice when it arrives here, 'tis the season. I
finished prepping for it an hour ago.
jsw

On 12/13/2022 3:32 PM, Jim Wilkins wrote:
> "Snag"  wrote in message news:tnae60$2ij1f$1@dont-email.me...
>
>   I was thinking 12 since it's evenly divisible by both 3 and 4 and I
> have 3 and 4 flute end mills - and a rotary table (7.5 turns per 30° at
> 90:1)  . It's raining here again and I have no other projects ... except
> the neighbor's SxS UTV , and I ain't working on it in the rain . So a
> little while ago I started roughing stock for this project . Yesterday
> it wasn't raining , but I wanted to watch the guys installing my new
> septic tank . Concrete this time , the last one was steel and only
> lasted about 18-19 years .
> Snag
> ---------------------
>
> Manual indexing is a tedious and error-prone task. You can double-check
> by setting dividers to the spacing of the first two holes and using them
> to confirm the next drilling location if you are interrupted. Any error
> should be large, a whole or half turn. My last dividing job was cutting
> a 68 tooth gear and there were issues... The one before that was 13, to
> spline a shaft for a motorcycle drive sprocket.
>
> That storm may be heavy snow or ice when it arrives here, 'tis the
> season. I finished prepping for it an hour ago.
> jsw

My table is still set up from cutting a pair of 58t 16dp gears for a
rolling mill project a guy from the Logan Lathe list is doing . A dozen
holes - well , dimples - is trifling compared to that . One of these
days I'm going to pin that set of 37/47 (IIRC) metric transposing change
gears I cut a while back . Haven't needed to cut metric threads yet so ...
--
Snag
"You can lead a dummy to facts
but you can't make him think."

"Snag" wrote in message news:tnb0j2$2k0qo$1@dont-email.me...

One of these
days I'm going to pin that set of 37/47 (IIRC) metric transposing change
gears I cut a while back . Haven't needed to cut metric threads yet so ...

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

You would have needed them if you didn't make them.

Shortly after buying the lathe I bought a metric transposing set of 127 and
120 teeth, since 120 instead of 100 gave more of the fine metric threads I
expected to need for the laser optics work I was doing then. Turns out the
engineer decided to move on and take the idea with him.
https://ieeexplore.ieee.org/document/9749702

At the time the gears cost around $40 each. I finally decided to make a
custom banjo stud to fit the double-keyed bushing that connects the gears,
since its bore is smaller than the South Bend stud. The price of the
standard 100 tooth gear is now up around $150 on Amazon, considerably more
from the industrial dealers I called. Making your own was a good call.
https://www.amazon.com/Boston-Gear-GB100A-Lightening-Pressure/dp/B004N62UIC

On 12/13/2022 8:05 PM, Jim Wilkins wrote:
> "Snag"  wrote in message news:tnb0j2$2k0qo$1@dont-email.me...
>
> One of these
> days I'm going to pin that set of 37/47 (IIRC) metric transposing change
>  gears I cut a while back . Haven't needed to cut metric threads yet so
> ...
>
> ------------------
>
> You would have needed them if you didn't make them.
>
> Shortly after buying the lathe I bought a metric transposing set of 127
> and 120 teeth, since 120 instead of 100 gave more of the fine metric
> threads I expected to need for the laser optics work I was doing then.
> Turns out the engineer decided to move on and take the idea with him.
> https://ieeexplore.ieee.org/document/9749702
>
> At the time the gears cost around $40 each. I finally decided to make a
> custom banjo stud to fit the double-keyed bushing that connects the
> gears, since its bore is smaller than the South Bend stud. The price of
> the standard 100 tooth gear is now up around $150 on Amazon,
> considerably more from the industrial dealers I called. Making your own
> was a good call.
> https://www.amazon.com/Boston-Gear-GB100A-Lightening-Pressure/dp/B004N62UIC
>

I got the RT shortly after I got the mill 'cuz I just knew ... turns
out the first gears I made were to repair some 2:1 reduction pairs in
the qcgb on my lathe . Those alone have saved me more than the cost of
the RT and all the gear cutters I've got . Logan wants like 160 bucks
for those little darlin's .
--
Snag
"You can lead a dummy to facts
but you can't make him think."