Anybody know where I can find feed/speed info for milling and drilling
Platinum Iridium? I've checked the Machinery's Handbook 25th ed., and
Machining Data Handbook 2nd ed. (CutData Machinability Data Center). Nada.

I need to mill some ~.050" slots and .030" holes in ~.060" thick x ~.625" x
~.100" Pt/Ir. I don't know the exact alloy. I do know the material is
fairly hard and tends to cook quality HSS drills regardless of spindle
speed.

TIA,
--
Skuke
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On Wed, 30 Mar 2005 22:07:54 GMT, skuke wrote:

Anybody know where I can find feed/speed info for milling and drilling
Platinum Iridium? I've checked the Machinery's Handbook 25th ed., and
Machining Data Handbook 2nd ed. (CutData Machinability Data Center). Nada.

I need to mill some ~.050" slots and .030" holes in ~.060" thick x ~.625" x
~.100" Pt/Ir. I don't know the exact alloy. I do know the material is
fairly hard and tends to cook quality HSS drills regardless of spindle
speed.

TIA,
When I've machined the stuff in the past HSS drills worked OK. The
smallest hole I was drilling was .008". Round stock at .020" O.D. also
turned well with HSS. If I was milling slots, and they ran the length
of the part I'd be looking at using a small carbide slitting saw blade
if HSS is giving you that much trouble. Otherwise I'd use a woodruff
key cutter. I don't remember the surface speed that I used but it was
real low because the highest spindle speeds available at the time were
real slow compared to the diameters being machined. Tool pressure was
constant and pretty high. If the drill dwelled the stuff would work
harden. Cutting oil was either a sulfurized oil or a non-staining
cutting oil made by Mobil. Mobilmet Omicron or Mobilmet Gamma. I think
it was the Omicron. I was also parting off .040 O.D. X .020 I.D.
tubing with HSS and did experience a couple of collapses. It was
because the feed wasn't high enough. The HSS parting tool had visible
wear. Increasing the feed solved the problem.
Eric R Snow,
E T Precision Machine

skuke wrote:

Anybody know where I can find feed/speed info for milling and drilling
Platinum Iridium? I've checked the Machinery's Handbook 25th ed., and
Machining Data Handbook 2nd ed. (CutData Machinability Data Center). Nada.

I need to mill some ~.050" slots and .030" holes in ~.060" thick x ~.625" x
~.100" Pt/Ir. I don't know the exact alloy. I do know the material is
fairly hard and tends to cook quality HSS drills regardless of spindle
speed.

TIA,
You could try a carbide drill. Kennametal sell a 1/32 carbide spade
style drill Cat No KWCD 00648 On page 12 of their drill cat (4.5 mb
download)
http://www.kennametal.com/images/pdf...wist_drill.pdf

On Wed, 30 Mar 2005 15:13:18 -0800, Eric R Snow wrote:


Tool pressure was
constant and pretty high.

Thanks. I did figure out that aggressive feeds were needed.



If the drill dwelled the stuff would work harden.

Yup. Got that right.



I was also parting off .040 O.D. X .020 I.D.
tubing with HSS and did experience a couple of collapses. It was
because the feed wasn't high enough. The HSS parting tool had visible
wear. Increasing the feed solved the problem.

I do a fair amount of small diameter, thin wall tubing (various hypo tubes)
and found that a really thin ThinBit works well to minimize tool pressure
and prevent collapse

Thanks for the tips.
--
Skuke
Reverse the domain name to send email