Is there any online chart for right RMP speed for different drill bits size and
different metals?
I know the cutting speed formula but having chart by drill press is easier than
calculating RMP every time.

Thanks,
Alex

"Alex" wrote in message
et...
Is there any online chart for right RMP speed for different drill bits
size and different metals?
I know the cutting speed formula but having chart by drill press is easier
than calculating RMP every time.

You may find it good metal exercise to calculate for every size. You really
don't have to be too close anyway. Are you using the (4 x CS)/Ø formula?
This one's easy to do in your head and it keeps the gears up there
greased...

Regards,

Robin

There have been several such graphs published over the years in HSM, PM, etc.

GWE

Robin S. wrote:

"Alex" wrote in message
et...

Is there any online chart for right RMP speed for different drill bits
size and different metals?
I know the cutting speed formula but having chart by drill press is easier
than calculating RMP every time.


You may find it good metal exercise to calculate for every size. You really
don't have to be too close anyway. Are you using the (4 x CS)/Ø formula?
This one's easy to do in your head and it keeps the gears up there
greased...

Regards,

Robin

"Grant Erwin" wrote in message
...
There have been several such graphs published over the years in HSM, PM,
etc.

GWE


True. Many of our radial arm drill presses at work have them. I do think
there's something to be said for keeping that skill fresh in one's mind
though.

Regards,

Robin

In , on Sun, 08 Jan 2006
20:57:11 GMT, Alex wrote:
Is there any online chart for right RMP speed for different drill bits size and
different metals?
I know the cutting speed formula but having chart by drill press is easier than
calculating RMP every time.

Just off the top of my head, I'd say the "right"
speed of the Royal Mounted Police... oh, never mind.

What do the symbols in the formula represent?
Thanks
Karl

"Robin S." wrote in message
...

"Alex" wrote in message
et...
Is there any online chart for right RMP speed for different drill bits
size and different metals?
I know the cutting speed formula but having chart by drill press is
easier
than calculating RMP every time.

You may find it good metal exercise to calculate for every size. You
really
don't have to be too close anyway. Are you using the (4 x CS)/Ø formula?
This one's easy to do in your head and it keeps the gears up there
greased...

Regards,

Robin

"Alex" wrote in message
et...
Is there any online chart for right RMP speed for different drill bits
size and different metals?
I know the cutting speed formula but having chart by drill press is easier
than calculating RMP every time.

I went through this exercise a while back. Didn't really find anything
extraordinarily useful.

I threw up the following page with conservative numbers for others' use

http://www.multi-drill.com/drill-speed-chart.htm

Regards,
Joe Agro, Jr.
(800) 871-5022
(908) 542-0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com

V8013-R

Also, http://www.autodrill.com/select.htm but I haven't really finished that
page yet and it looks a bit ... well... unfininished.
--


Regards,
Joe Agro, Jr.
(800) 871-5022
(908) 542-0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com

V8013-R

"everyman" wrote in message
...
What do the symbols in the formula represent?
Thanks
Karl


RPM = (4 x CS)/Ø

Whe

CS is the cutting speed of the work piece given a certain cutter material in
Surface Feet per Minute. When cutting mild steel with a HSS tool, 100 is
about right. Aluminium with a HSS tool is about 300. When using a carbide
tool, multiply said numbers by 3-5x.

Ø is the diameter of the cutter when the cutter is spinning (drilling and
milling), and the diameter of the work when the work is spinning (lathe).

For instance, 1/4" HSS drill bit drilling aluminium:

RPM = (4 x CS)/Ø
= (4 x 300)/.25
= 1200/.25
= 4800

Note: These cutting speed numbers are under ideal conditions. If you're
feeding by hand using a single-phase drill press, you'll probably have to go
slower to get a stable cut. I usually go 60-80% of whatever number I get
using the formula. YMMV.

HTH.

Regards,

Robin

According to Robin S. :

"everyman" wrote in message
...
What do the symbols in the formula represent?

[ ... ]

Ø is the diameter of the cutter when the cutter is spinning (drilling and
milling), and the diameter of the work when the work is spinning (lathe).

One minor complaint about this one. While reading it in the
newsreader, it shows up as a zero with a slash through it, in my editor,
it shows up as an octal value (330) preceded by a backslash '\'.

It is one of those "extended ASCII" characters which cannot be
depended upon to be the same on all systems. You probably had to do
something strange on the keyboard to generate it.

It is better to use something like "(Dia)" instead, so the
weirdness of the character's display does not become a problem.

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 ---

Thanks
I learn something new every day I read this group.
Thanks
Karl

"Robin S." wrote in message
...

"everyman" wrote in message
...
What do the symbols in the formula represent?
Thanks
Karl


RPM = (4 x CS)/Ø

Whe

CS is the cutting speed of the work piece given a certain cutter material
in
Surface Feet per Minute. When cutting mild steel with a HSS tool, 100 is
about right. Aluminium with a HSS tool is about 300. When using a carbide
tool, multiply said numbers by 3-5x.

Ø is the diameter of the cutter when the cutter is spinning (drilling and
milling), and the diameter of the work when the work is spinning (lathe).

For instance, 1/4" HSS drill bit drilling aluminium:

RPM = (4 x CS)/Ø
= (4 x 300)/.25
= 1200/.25
= 4800

Note: These cutting speed numbers are under ideal conditions. If you're
feeding by hand using a single-phase drill press, you'll probably have to
go
slower to get a stable cut. I usually go 60-80% of whatever number I get
using the formula. YMMV.

HTH.

Regards,

Robin

On Mon, 9 Jan 2006 12:22:23 -0500, "Robin S."
wrote:

RPM = (4 x CS)/Ø

Whe

CS is the cutting speed of the work piece given a certain cutter material in
Surface Feet per Minute. When cutting mild steel with a HSS tool, 100 is
about right. Aluminium with a HSS tool is about 300. When using a carbide
tool, multiply said numbers by 3-5x.

Ø is the diameter of the cutter when the cutter is spinning (drilling and
milling), and the diameter of the work when the work is spinning (lathe).

For instance, 1/4" HSS drill bit drilling aluminium:

RPM = (4 x CS)/Ø
= (4 x 300)/.25
= 1200/.25
= 4800

Note: These cutting speed numbers are under ideal conditions. If you're
feeding by hand using a single-phase drill press, you'll probably have to go
slower to get a stable cut. I usually go 60-80% of whatever number I get
using the formula. YMMV.

Hi Robin,

Using the formula you posted above, I took the liberty to
create a small spread sheet and publish it to pdf. I went
from 1/32 to 2 inches via 1/32 steps.

The hard work (yeah right...) is done. If anyone spots an
error or has a suggestion to make it better say so.

See:

http://www.iserv.net/~lfisk/drillbitrpm.pdf

If someone wants to host this it would be fine by me, that
is if Robin approves too. I'll leave it up for a week or
two. My webspace/traffic is really limited...

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

100's a little hot for MS using HSS tools, I learned to use 60 ...

GWE

Leon Fisk wrote:
On Mon, 9 Jan 2006 12:22:23 -0500, "Robin S."
wrote:


RPM = (4 x CS)/Ø

Whe

CS is the cutting speed of the work piece given a certain cutter material in
Surface Feet per Minute. When cutting mild steel with a HSS tool, 100 is
about right. Aluminium with a HSS tool is about 300. When using a carbide
tool, multiply said numbers by 3-5x.

Ø is the diameter of the cutter when the cutter is spinning (drilling and
milling), and the diameter of the work when the work is spinning (lathe).

For instance, 1/4" HSS drill bit drilling aluminium:

RPM = (4 x CS)/Ø
= (4 x 300)/.25
= 1200/.25
= 4800

Note: These cutting speed numbers are under ideal conditions. If you're
feeding by hand using a single-phase drill press, you'll probably have to go
slower to get a stable cut. I usually go 60-80% of whatever number I get
using the formula. YMMV.


Hi Robin,

Using the formula you posted above, I took the liberty to
create a small spread sheet and publish it to pdf. I went
from 1/32 to 2 inches via 1/32 steps.

The hard work (yeah right...) is done. If anyone spots an
error or has a suggestion to make it better say so.

See:

http://www.iserv.net/~lfisk/drillbitrpm.pdf

If someone wants to host this it would be fine by me, that
is if Robin approves too. I'll leave it up for a week or
two. My webspace/traffic is really limited...

"Grant Erwin" wrote in message
...
100's a little hot for MS using HSS tools, I learned to use 60 ...

GWE

Leon Fisk wrote:


That depends. If you are doing high production work, where you can gauge
pretty accurately how long your tool will last, you may decide that the
increased productivity is worth the higher cost of quickly dulling your
cutters. Of course, if you are doing that kind of work you're probably using
carbide...


Dave,
Who also uses 60 sfm.

On Tue, 10 Jan 2006 13:17:04 -0800, Grant Erwin
wrote:

100's a little hot for MS using HSS tools, I learned to use 60 ...

Hi Grant,

That is easy enough to change in the formula. I'll wait a
bit and see what other comments come in. Like I said the
main work is done, changing formulas, more sizes and stuff
won't take much. If anyone wants other materials added, I do
need the formula for them though...

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

"Grant Erwin" wrote in message
...
100's a little hot for MS using HSS tools, I learned to use 60 ...

GWE


Grant,

I agree with you. Unfortunately any value in the machinery handbook (or
otherwise) is an estimation.

I find that the rather brutal entry into, and exit out of the material the
drill bit makes severely decreases its edge life (manually fed). Similarly,
it's actually very difficult to tell when an endmill on a CNC mill is dull
by looking only at the cutter. They don't look burnt or chipped as when they
are used manually. I attribute this phenomenon to the entry, exit, and their
inconsistent feed while in the work.

I have the luxury at work of using massive radial arm drill presses with
geared power feeds and huge cast iron bases which make for very powerful and
rigid machines. Using flood coolant and a quality bit, one can feed
appropriately for 100fpm in mild steel. Similarly, it is easily possible to
burn the same bit at 60fpm because the feedrate is set too high.

Perhaps Leon should change his spreadsheet to reflect values suitable for a
hand-fed tool in mild steel (60fpm). I'd be inclined to leave the aluminium
and the mild steel w/ carbide the same though as the cutter tends not to
fail in the same way.

/rambling

Regards,

Robin

http://www.iserv.net/~lfisk/drillbitrpm.pdf

If someone wants to host this it would be fine by me, that
is if Robin approves too. I'll leave it up for a week or
two. My webspace/traffic is really limited...

Why not just post it to the dropbox once it's finalized?

http://www.metalworking.com/dropbox.html
http://metalworking.com/DropBox/

Best Regards,
Keith Marshall


"I'm not grown up enough to be so old!"


"Leon Fisk" wrote in message
...
On Mon, 9 Jan 2006 12:22:23 -0500, "Robin S."
wrote:

RPM = (4 x CS)/Ø

Whe

CS is the cutting speed of the work piece given a certain cutter material
in
Surface Feet per Minute. When cutting mild steel with a HSS tool, 100 is
about right. Aluminium with a HSS tool is about 300. When using a carbide
tool, multiply said numbers by 3-5x.

Ø is the diameter of the cutter when the cutter is spinning (drilling and
milling), and the diameter of the work when the work is spinning (lathe).

For instance, 1/4" HSS drill bit drilling aluminium:

RPM = (4 x CS)/Ø
= (4 x 300)/.25
= 1200/.25
= 4800

Note: These cutting speed numbers are under ideal conditions. If you're
feeding by hand using a single-phase drill press, you'll probably have to
go
slower to get a stable cut. I usually go 60-80% of whatever number I get
using the formula. YMMV.

Hi Robin,

Using the formula you posted above, I took the liberty to
create a small spread sheet and publish it to pdf. I went
from 1/32 to 2 inches via 1/32 steps.

The hard work (yeah right...) is done. If anyone spots an
error or has a suggestion to make it better say so.

See:

http://www.iserv.net/~lfisk/drillbitrpm.pdf

If someone wants to host this it would be fine by me, that
is if Robin approves too. I'll leave it up for a week or
two. My webspace/traffic is really limited...

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

On Wed, 11 Jan 2006 03:06:22 -0500, "Robin S."
wrote:


"Grant Erwin" wrote in message
...
100's a little hot for MS using HSS tools, I learned to use 60 ...

GWE


Grant,

I agree with you. Unfortunately any value in the machinery handbook (or
otherwise) is an estimation.

I find that the rather brutal entry into, and exit out of the material the
drill bit makes severely decreases its edge life (manually fed). Similarly,
it's actually very difficult to tell when an endmill on a CNC mill is dull
by looking only at the cutter. They don't look burnt or chipped as when they
are used manually. I attribute this phenomenon to the entry, exit, and their
inconsistent feed while in the work.

I have the luxury at work of using massive radial arm drill presses with
geared power feeds and huge cast iron bases which make for very powerful and
rigid machines. Using flood coolant and a quality bit, one can feed
appropriately for 100fpm in mild steel. Similarly, it is easily possible to
burn the same bit at 60fpm because the feedrate is set too high.

Perhaps Leon should change his spreadsheet to reflect values suitable for a
hand-fed tool in mild steel (60fpm). I'd be inclined to leave the aluminium
and the mild steel w/ carbide the same though as the cutter tends not to
fail in the same way.

/rambling

Regards,

Robin

Well after looking at Joe's (of Auto Drill) I completely
changed it to reflect HSS only and added more materials. I
also increased its coverage. It starts at 1/32 and continues
to 2 inches via 1/32 steps and then continues to 8 via 1/4
inch steps. The latter sizes I think could be useful for
lathe work. I decreased the speeds, leaning to the low side
(thanks Grant) which most of us would find of use with
smaller machines.

This is the link to the new pdf:

http://www.iserv.net/~lfisk/drillbitrpm2.pdf

This is the link to the pdf and xls spreadsheet zipped:

http://www.iserv.net/~lfisk/drillbitrpm.zip

This zip archive has the pdf and the spreadsheet I used to
create it. The spreadsheet is Excel (xls) and I can't
guarantee it will work. It is an export from Quattro Pro
(ancient version). I don't have anything else that can load
it and I didn't figure anyone would want it in Quattro
format... You can easily change the SPM (surface feet per
minute) values in one spot for each material and get your
own preferred output via the spreadsheet.

Let me know what's wrong now ;-)
--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

On Wed, 11 Jan 2006 16:14:24 GMT, "Keith Marshall"
wrote:

http://www.iserv.net/~lfisk/drillbitrpm.pdf

If someone wants to host this it would be fine by me, that
is if Robin approves too. I'll leave it up for a week or
two. My webspace/traffic is really limited...

Why not just post it to the dropbox once it's finalized?

http://www.metalworking.com/dropbox.html
http://metalworking.com/DropBox/

Best Regards,
Keith Marshall

Hi Keith,

That should work. I just re-read the rules and I see that I
could zip the spreadsheet and submit it that way. I knew
there were some restrictions on file formats and I couldn't
remember just what it was.

Waiting to see what is thought of my last attempt now in
another thread...
--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

You folks are makeing this way more complicated than it needs to be.
Using a mild steel work piece & a high speed steel tool, if the
round thing is 4" diameter it should turn 100 RPM, if it's
1" diameter it can turn 400 RPM. Aluminum can go faster &
exotics like stainless & tool steel way slower. In a home/ hobby
situation you can reduce the spindle speed by 1/2 and still be time
ahead by not having to sharpen as often. In a production situation
all formulas, tables ,etc. are only a starting point any way as there
are infinite variations due to material alloys, tool alloys &
shapes, coolants, machine rigidity ad infinitum so that optomizing
spindle speed is a matter of experimenting to push the edge of the
envelope.
If youre only doing one or two pieces, the vast majority of your time
is spent in other than the actual cutting process any way.