morsetaper2
Diamond
- Joined
- Jul 2, 2002
- Location
- Gaithersburg, MD USA
Invar: Drilling Small .043 Inch Holes
Machinist at work is out for an extended period. I'm a mechanical engineer, but when odd-ball fixes need to be done I get tapped to do them when its an emergency and machinist is out. I'm no journeyman machinist by any means. Competent in alum, steel, brass, some stainless, various plastics, etc.
I have zero experience working with invar.
I believe the material is invar 36 FM. And the parts are nickel plated. I need to drill 3 small .043 diameter holes in five parts (15 holes). These are expensive optical mounts so I don't want to ruin them.
I'll be using .043 carbide drills. Exact hole size and position is not critical. I read some posts about drilling invar. But none were for drilling small drill holes. Read that it work hardens. I'll be drilling into a tube that is hexagonal on the outside with a round ID. Where the hole needs to go wall thickness is about .100 thick.
Any advice so I don't screw this up? Work will be done on a Bridgeport clone.
Drill RPM for .043 carbide drill?
Drill RPM for .043 HSS drill?
Coolant: oil or water based?
Will it act unusual when drill breaks through to ID?
Thanks.
Machinist at work is out for an extended period. I'm a mechanical engineer, but when odd-ball fixes need to be done I get tapped to do them when its an emergency and machinist is out. I'm no journeyman machinist by any means. Competent in alum, steel, brass, some stainless, various plastics, etc.
I have zero experience working with invar.
I believe the material is invar 36 FM. And the parts are nickel plated. I need to drill 3 small .043 diameter holes in five parts (15 holes). These are expensive optical mounts so I don't want to ruin them.
I'll be using .043 carbide drills. Exact hole size and position is not critical. I read some posts about drilling invar. But none were for drilling small drill holes. Read that it work hardens. I'll be drilling into a tube that is hexagonal on the outside with a round ID. Where the hole needs to go wall thickness is about .100 thick.
Any advice so I don't screw this up? Work will be done on a Bridgeport clone.
Drill RPM for .043 carbide drill?
Drill RPM for .043 HSS drill?
Coolant: oil or water based?
Will it act unusual when drill breaks through to ID?
Thanks.
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