Drilling with the Knee

ddickey

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H-M Supporter Gold Member
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Some people prefer to drill on the mill by raising the knee rather than lowering the quill.
What do you do?
Advantages? Disadvantages?
Doesn't the table shift when lowering? I suppose it wouldn't matter..?
 
Kind of depends on the machine and the material- I used the knee once when milling a hole in brass- I didn't want to risk my bit grabbing and pulling the quill down and ruining the part. Brass is very "tenacious" and grabby
 
Quill if the machine has one, knee or saddle if it doesn't (if doing work with a horizontal machine without an overhead, etc.).

Ted
 
Some people prefer to drill on the mill by raising the knee rather than lowering the quill.
What do you do?
Advantages? Disadvantages?
Doesn't the table shift when lowering? I suppose it wouldn't matter..?
Some of older mills do not have quill
If using brigport mill has a light duty feed on the quill so drill larger holes need the knee

Dave

Sent from my SAMSUNG-SM-J320A using Tapatalk
 
I use the knee on my Bridgeport for drilling or milling blind holes. The dial on the knee is much more accurate than the scale on the quill. If the hole has to be in a relatively precise location I lock the table in both the X and Y axis. If accuracy is necessary I use an undersize drill and finish with the proper size end mill.

When precise location isn't necessary (+/- .005" or more in depth or location ) use the quill.
 
I always use the quill as I have DRO for depth measurement's. If I'm drilling stuff like UHMW I use the fine feed option this way the bit won't get sucked into the part. UHMW is really bad for this.
 
Some people prefer to drill on the mill by raising the knee rather than lowering the quill.
What do you do?

I have a 102-year old Cincinnati horizontal mill with a vertical head. Early pictures here.
No choice; if I want the benefit of the lead screw feed dials for hole distances than I have to crank the (guessing ~500lb?) knee up and down.

Disadvantages?

No feedback; I can't feel a thing about the drilling operation especially on smaller diameter drill bits.
Always scared of breaking them.

-brino
 
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