Slitting on a mill
 

I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

Slitting on a mill
 

"Gerry" wrote in message
...
I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

I hate slitting saws! Slow feed, robust rigid set-up, flood coolant, silent
prayers! Can you use a hacksaw or a Sawsall?

Slitting on a mill
 

On Jun 1, 8:06*pm, "Buerste" wrote:
"Gerry" wrote in message

...

I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

I hate slitting saws! *Slow feed, robust rigid set-up, flood coolant, silent
prayers! *Can you use a hacksaw or a Sawsall?

I cannot cut straight with either. Hoping to get a cut better than I
could do with a hacksaw

Slitting on a mill
 

On Jun 1, 6:16*pm, Gerry wrote:
On Jun 1, 8:06*pm, "Buerste" wrote:

"Gerry" wrote in message

....

I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

I hate slitting saws! *Slow feed, robust rigid set-up, flood coolant, silent
prayers! *Can you use a hacksaw or a Sawsall?

I cannot cut straight with either. Hoping to get a cut better than I
could do with a hacksaw

In my limited experience, the easiest thing to do is to stick the saw.
I never use an arbor with a key, so the saw can slip if pressed really
hard. 1/16 is awfully thin and weak and easy to bugger up if pressed
too hard.

Go slowly, particularly at first, and cut a slight amount across where
you want a slit. You need something to guide the saw as it cuts more,
and the first one or two cuts will provide the guidance. Then you can
cut a little more agressive. As said, use lots of coolant and keep the
teeth cleaned out with a chip brush.

Paul

Slitting on a mill
 

"Gerry" wrote in message
...
On Jun 1, 8:06 pm, "Buerste" wrote:
"Gerry" wrote in message

...

I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

I hate slitting saws! Slow feed, robust rigid set-up, flood coolant,
silent
prayers! Can you use a hacksaw or a Sawsall?

I cannot cut straight with either. Hoping to get a cut better than I
could do with a hacksaw
***********************

Does in need to be straight?

Slitting on a mill
 

I don't know about your machine - mine is a bit larger - but the only time I
had trouble with a slitting saw was when I inadvertently ran the spindle in
reverse. I used no coolant, I used the speed designated for that diameter
cutter, and a slow enough feed that the teeth wouldn't load up - I was
cutting stainless steel and had no problems, you should have no problems in
mild steel - if you are worried about feed speed, hand feed it so it "feels
right"

"Gerry" wrote in message
...
I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

Slitting on a mill
 

" wrote in message
...
On Jun 1, 6:16 pm, Gerry wrote:
On Jun 1, 8:06 pm, "Buerste" wrote:

"Gerry" wrote in message

...

I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

I hate slitting saws! Slow feed, robust rigid set-up, flood coolant,
silent
prayers! Can you use a hacksaw or a Sawsall?

I cannot cut straight with either. Hoping to get a cut better than I
could do with a hacksaw

In my limited experience, the easiest thing to do is to stick the saw.
I never use an arbor with a key, so the saw can slip if pressed really
hard. 1/16 is awfully thin and weak and easy to bugger up if pressed
too hard.

Go slowly, particularly at first, and cut a slight amount across where
you want a slit. You need something to guide the saw as it cuts more,
and the first one or two cuts will provide the guidance. Then you can
cut a little more agressive. As said, use lots of coolant and keep the
teeth cleaned out with a chip brush.

Paul


no, no NO NO NO NO - everything I've read, my limited experience, and the
advice of much more experienced "real" machists is universally to do a
slitting saw cut in one pass - set it to the desired depth and make the
cut - adjust the feed rate as required, but don't make multiple passes, you
will just get a messy cut and put the saw at increased risk.

Slitting on a mill
 

On 2010-06-02, Gerry wrote:
I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

You *could* go into _Machinery's Handbook_ and look up all the
formulas. But for convenience, my old McDonnell Douglas feeds and
speeds calculator (slide rule type, plus built in lookup tables for
materials) says:

ALLOY: SFPM: Chip load per tooth
Annealed alloys: 70-90 0.006
Soft carbon steel: 80-120 0.007

Let's be conservative, and pick Annealed alloys, so for the middle of
the range (80 SFPM), and a 3" diameter cutter, you want about 102 RPM.

And for 30 teeth, you want about 1.83 in/min feed rate.

Now -- the first question is whether your drill/mill can get
down to 100 RPM. If not, you will be burning up your cutter.

This is really the sort of thing at which a horizontal spindle
mill excels, and I have my doubts about a mill/drill (or drill/mill as
you show it). The fact that "drill" is before "mill" in the term
suggests that it is more optimized as a drill press, and may not have
spindle speeds slow enough for your task in steel.

And the inches/minute feed rate presumes a power feed, which you
are unlikely to have.

What kind of spindle does this machine have? There are arbors
for use with slitting saws and narrow mills which fit R8 spindles. If
your machine has a Morse spindle, I'm not so sure what is available.

Use a cutting fluid -- at least something like Rigid high sulfur
threading oil (sold for pipe threading). At this slow a spindle speed,
you probably won't be throwing the coolant around at least. :-)

In any case, I would advise not going much more than about 1/16"
(the width of your cutter) of depth per pass -- especially until you get
the feel of your machine under this kind of loads. And it sounds as
though you won't be doing enough cutting of this sort to really get the
feel of it.

Good Luck,
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 ---

Slitting on a mill
 

"Bill Noble" wrote in message
...


" wrote in message
...
On Jun 1, 6:16 pm, Gerry wrote:
On Jun 1, 8:06 pm, "Buerste" wrote:

"Gerry" wrote in message

...

I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

I hate slitting saws! Slow feed, robust rigid set-up, flood coolant,
silent
prayers! Can you use a hacksaw or a Sawsall?

I cannot cut straight with either. Hoping to get a cut better than I
could do with a hacksaw

In my limited experience, the easiest thing to do is to stick the saw.
I never use an arbor with a key, so the saw can slip if pressed really
hard. 1/16 is awfully thin and weak and easy to bugger up if pressed
too hard.

Go slowly, particularly at first, and cut a slight amount across where
you want a slit. You need something to guide the saw as it cuts more,
and the first one or two cuts will provide the guidance. Then you can
cut a little more agressive. As said, use lots of coolant and keep the
teeth cleaned out with a chip brush.

Paul


no, no NO NO NO NO - everything I've read, my limited experience, and the
advice of much more experienced "real" machists is universally to do a
slitting saw cut in one pass - set it to the desired depth and make the
cut - adjust the feed rate as required, but don't make multiple passes,
you will just get a messy cut and put the saw at increased risk.

Well, I'm certainly not a "real" machinist, but I have used slitting saws,
on a cnc mill.
I used multiple passes, with no problem, and intuition tells me this is the
safer, better way -- altho my intuition is by no means infallible.

I use these on 1x3" rect alum bar, 3 ft lengths, to get various cross
sections lengthwise, mostly 1x2 for vise jaws.
The cut is very accurate, altho I used 3/32 or 1", with "side teeth". iirc,
I would cut about 1/8" deep in each pass.

Keep in mind there are slitting saws, slotting saws, jewelers saws, and
thicker side milling cutters.

I think everyone will agree, tho: go slow, slow rpm, plenty of coolant.
--
EA

Slitting on a mill
 

"Buerste" wrote in message
...

"Gerry" wrote in message
...
On Jun 1, 8:06 pm, "Buerste" wrote:
"Gerry" wrote in message

...

I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

I hate slitting saws! Slow feed, robust rigid set-up, flood coolant,
silent
prayers! Can you use a hacksaw or a Sawsall?

I cannot cut straight with either. Hoping to get a cut better than I
could do with a hacksaw
***********************

Does in need to be straight?

With your equipment, Buerste has the best advice. With a bit of ingenuity,
you can make saw guides out of shim stock and scrap rectangles. I frequently
make clamping bushings this way.

Karl

Slitting on a mill
 

On Jun 1, 9:16*pm, Gerry wrote:
...
I cannot cut straight with either. Hoping to get a cut better than I
could do with a hacksaw

This is a good opportunity to learn. Use a new blade, mark the line on
two faces, start at the corner and cut a shallow kerf down each line.
The kerf guides the blade while you cut deeper. With practice you
won't need it but it helps at first.

I have a lot of trouble with thin slitting saws. I set the drive belt
fairly loose and reduce depth of cut if it jams.

jsw

Slitting on a mill
 

Slitting is not difficult, but like all cutting operations, the number one problem is always chip clearance. In that respect,
slitting saws have no kerf in the teeth, so chip clearance is critical. I use compressed air. If coolant is used, it must be a
high volume flood. Full cut or small passes is the same for me.
Steve

"Gerry" wrote in message ...
I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

Slitting on a mill
 

"Karl Townsend" wrote in message
anews.com...

"Buerste" wrote in message
...

"Gerry" wrote in message
...
On Jun 1, 8:06 pm, "Buerste" wrote:
"Gerry" wrote in message

...

I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance

I hate slitting saws! Slow feed, robust rigid set-up, flood coolant,
silent
prayers! Can you use a hacksaw or a Sawsall?

I cannot cut straight with either. Hoping to get a cut better than I
could do with a hacksaw
***********************

Does in need to be straight?

With your equipment, Buerste has the best advice. With a bit of ingenuity,
you can make saw guides out of shim stock and scrap rectangles. I
frequently make clamping bushings this way.

Karl



I found out a while ago that I get no points for neatness.

Slitting on a mill
 

Thank you all!

Slitting on a mill
 

Gerry wrote:
I need to slit a piece of mild steel 0.500" thick and 0.875 deep to a
0.652 hole. This will be a clamp to attach to a motor shaft. Never
used a slitting saw before, therefore I am asking for any advice.
Using a drill/mill with a 3X1/16X1 30 tooth saw. Thanks in advance


One problem that can give you grief is having stresses in the metal that
will cause the cut to close on the saw. This doesn't happen all the
time but when it does you will have a mess. If you properly clamp the
work on both sides of the cut to keep it from springing and grabbing the
saw you will not have this problem.

John

Slitting on a mill
 

John wrote:

One problem that can give you grief is having stresses in the metal that
will cause the cut to close on the saw. This doesn't happen all the
time but when it does you will have a mess. If you properly clamp the
work on both sides of the cut to keep it from springing and grabbing the
saw you will not have this problem.

Yup, I've been burned many times by this. I just wish I had kept notes on what material
and treatments closed up and which that seemed to open.

Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller