Hi guys, I have a job coming up where I need to drill and ream 1-3/8" dia hole, 6.25" deep.
Here is the thing. I typically never use HSS drills over 1/2" as I am used to indexable insert drills. The part I am doing is 2 blocks sandwiched together with a 3/16" shim in between to create the 11/16 radius on each part.
I do not know where to start with this big of a drill for feed. SFM I'm fine with. I was thinking these speeds/feeds for a 1.343" drill in A36 steel.
80SFM - .015/rev with a 1/4" peck.
The machine I have is 50 Taper, 20/25 HP. Spindle changes gears at 782RPM.
The torque is 657/532 Foot Pounds.
I believe the machine will take the power no problem. My concern is will the drill at that feed?
I read somewhere on here before about someone mentioning drill diameter divided by 64 = feed/rev.
That would make my feed about .021 Seems a lot?
Standard #4 taper twist drill is whats being used.
Here is the thing. I typically never use HSS drills over 1/2" as I am used to indexable insert drills. The part I am doing is 2 blocks sandwiched together with a 3/16" shim in between to create the 11/16 radius on each part.
I do not know where to start with this big of a drill for feed. SFM I'm fine with. I was thinking these speeds/feeds for a 1.343" drill in A36 steel.
80SFM - .015/rev with a 1/4" peck.
The machine I have is 50 Taper, 20/25 HP. Spindle changes gears at 782RPM.
The torque is 657/532 Foot Pounds.
I believe the machine will take the power no problem. My concern is will the drill at that feed?
I read somewhere on here before about someone mentioning drill diameter divided by 64 = feed/rev.
That would make my feed about .021 Seems a lot?
Standard #4 taper twist drill is whats being used.