Drill a square hole anyone?
- Thread starter 4V50 Gary
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FrankenMauser
New member
Here I was, expecting some kind of new broaching tool...
...watching a milling process that resembles a rotary engine, more than a drill.
Pretty sweet.
...watching a milling process that resembles a rotary engine, more than a drill.
Pretty sweet.
claymore1500
New member
Square bullets anyone?
Ideal Tool
Moderator
"Square bullets anyone?" Puckle-Gun..cylinders for both round & square bullets..round one for Christians..square for Turks.
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I did not go to the link,but as I recall,a three flute drill in a floating holder will give a four sided hole.
Most of us know how to drill a three sided hole in sheet metal with a two flute drill.
I spent some time running an old 1950 something American Broach machine.
The limitation on a broach is how much chip you can pull in the gullet of a tooth.But,doggone,what an efficient,amazing,simple machine!!Squares,dees,splines,.Its perfect for a part like an AR barrel extension.Old school,but,load the part,load the broach,and draw it though!!
Most of us know how to drill a three sided hole in sheet metal with a two flute drill.
I spent some time running an old 1950 something American Broach machine.
The limitation on a broach is how much chip you can pull in the gullet of a tooth.But,doggone,what an efficient,amazing,simple machine!!Squares,dees,splines,.Its perfect for a part like an AR barrel extension.Old school,but,load the part,load the broach,and draw it though!!
mkk41,I have done a lot of sinker edm work,and they are a great tool.
But,for many applications,the broach is far more efficientThis thing stood about 8 feet tall,and part of it was below the floor.I'd guess the hydraulic ram was 6 in or 8 in.It had a chuck type fixture that would hold the lower end of the broach,easy load/unload.It worked below the table.There was a floating center for the upper end of the broach.The broaches themselves were 2 to 3 feet long,most of them,except for the real small ones.
But you just clean the fixture on the table,load the part, the broach through a hole in the part,and draw the broach through.A typical "cut" might take 3 to 5 seconds,to to what an edm would take several minutes to a chunk of an hour to cut.If you are blasting with the EDM,surface finish will be rough.To get a fine finish,takes time,and generally another electrode..And,the broach leaves no recast skin,subject to cracking.
A man on a broach can go through,say 5 or 8 different setups in a shift,and pull 30 or 50 or 100 parts each setup.
I love the EDM,I built molds.But an old broach is a producing machine!!
I have also used similar tooling on an old Monarch EE toolroom lath to make 6 sided allen wrench pockets.
And,agreed on reshaping a drilled hole,the broach is a through hole machine.It wont do a blind hole
But,for many applications,the broach is far more efficientThis thing stood about 8 feet tall,and part of it was below the floor.I'd guess the hydraulic ram was 6 in or 8 in.It had a chuck type fixture that would hold the lower end of the broach,easy load/unload.It worked below the table.There was a floating center for the upper end of the broach.The broaches themselves were 2 to 3 feet long,most of them,except for the real small ones.
But you just clean the fixture on the table,load the part, the broach through a hole in the part,and draw the broach through.A typical "cut" might take 3 to 5 seconds,to to what an edm would take several minutes to a chunk of an hour to cut.If you are blasting with the EDM,surface finish will be rough.To get a fine finish,takes time,and generally another electrode..And,the broach leaves no recast skin,subject to cracking.
A man on a broach can go through,say 5 or 8 different setups in a shift,and pull 30 or 50 or 100 parts each setup.
I love the EDM,I built molds.But an old broach is a producing machine!!
I have also used similar tooling on an old Monarch EE toolroom lath to make 6 sided allen wrench pockets.
And,agreed on reshaping a drilled hole,the broach is a through hole machine.It wont do a blind hole
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