Ideas upon Internal Helical groove cutting

[brianklein]

I'm try to find out if you can use a CNC machining center or a CNC Lathe for cutting an oil groove into a 7/16 hole in a 7" thick piece of steel that has a pitch of 1 full rotation in 16 inches. Is it possible???

[brianklein]

anyone???

[RICHARD ZASTROW]

Kinda sounds like rifling a .44 cal. or 11 mm gun barrel. lol

Dick Z

[keebler303]

Sounds to me like a job for a lathe with live tooling. it may be possible with a machining center with a long tool and a helical tool path.

How big does the groove have to be?

Matt

[ctate2000]

How deep and wide? You may be able to do this on a CNC lathe with a g33 command. I have not put all the varibales togehter in my head yet. I need a little more info.

[VWSatOz]

1st make a master to press-drive this spiral in with a long mandrel with a tool bit poking out. The master sleeve can have bigger diameter so you can get a larger diameter flycutter tool shank down through using helical interpolation on CNC mill.
I dont believe its an oil groove. Rifling with one slot? sounds like a better description.

[RICHARD ZASTROW]

Thats what it sounded like to me also. Index the part six times and it becomes 6 groove rifling. But then I'm a conspiracy theorist. lol

Dick Z

[sluggo]

maybe it is for some grease? with a pitch that steep you have to watch out for clearance on the back side of your tool, when you helix it in a mill.

[brianklein]

i'm cutting an oil groove into a 7/16 hole in a 7" thick piece of steel. The groove is about .147 wide.

[Mitsui Seiki]

Originally Posted by brianklein I'm try to find out if you can use a CNC machining center or a CNC Lathe for cutting an oil groove into a 7/16 hole in a 7" thick piece of steel that has a pitch of 1 full rotation in 16 inches. Is it possible???

It's possible but the question is.What kind of tool to do it?

[RICHARD ZASTROW]

Does the workpiece permit installing a sleeve? Possibly you could cut the groove thru from the outside of the sleeve then shrink fit the sleeve into an appropriately sized bore. I'm ASSuming both ends are full circle to retain the oil? Just a thought.

Dick Z

[Delw]

Like mitsui said its possible but the tooling will more than likely need to be custom made.
it would work alot better on a mill.
a lathe would be difficult due to the length and dia. the problem you will run into is your insert will be extreamly thing due to the helix, you will have to have a lot of clearance in that insert due to depth and width.

with a mill you would be able to do half of it turn it over and do the other have, unless you have a c axis on a lathe it would be pretty hard to match up the grooove after flipping it over.

doing 3.5" at a time wouldnt be so bad, not near as bad as doing the full 7.
plus doing with this mill vs a lathe you can pretty much take the cut to full depth, a lathe with that type of tool would be pretty hard to do because of multiple pass's then your tool would need to be much thinner, you size and finish probally wouldnt fly on a lathe if you could get it to work.
Just get a key way type cutter custom made and make sure it has clearance for the helix pitch as the id will rub on the back side.