Lathe I.D threading bar

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I need to make some approx. 1 3/8" -24  I.D threads , left hand on one side and right hand thread on the other. I was going to buy a I.D threading bar with the carbide inserts , but when i looked at the price i can't believe how much they want. Starting at 100$ for the bar another 22$ a piece for the inserts. This was at Kar.Is there another tooling companies i might be able to buy one from for cheaper or another ideas? Its for a bike bottom bracket.
Reply:I'm assuming that you are going to cut them in a lathe.  If so find a boring bar that will accept a 1/4" HSS bit and grind it to cut a 60 degree thread and go to work.  (I'm assuming you want 60 degree threads) but you can grind a tool bit to match anything.I'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:will a set of taps work for you ?I have a left and right 1 3/8 24 hand tap250DXMM251MM175225G plus 251D-1
Reply:How deep are you cutting threads.A tool like this will get you about 1.5" deep. Attached ImagesA butterfly without wings, is just an ugly bug
Reply:The threads only need to be about an 1" deep. The tool bits might work. There was another tool i saw for alot cheaper , not sure what it accepts for cutters.Last edited by Bikespot; 03-17-2009 at 12:08 PM.
Reply:As Hammack_Welding, said above, you can get round steel boring bars in various diameters, which take square HSS toolbits. They are easy to grind accurately and you can use the bar for boring or threading or recessing, just by having a few different, cheap toolbits. A 3/4" bar from ENCO, which has its hole on one end at 90* to the axis, the other end at 45*, costs about $9.What type of tool holders do you have; that determines what you can use.
Reply:Any of these will work. Attached ImagesA butterfly without wings, is just an ugly bug
Reply:Originally Posted by Magnetic MechanicAny of these will work.
Reply:You can just make one also. Simple. I could have that threading bar made in about 1/2 hour. I use the threading carbide tooling from MSC. They are around 6.00 a piece. All ready cut at 60 degrees for you. You might have to grind a little clearance if needed.
Reply:I take it you are cutting threads up to a shoulder,  which makes that  boring bar impractical.But the other end looks like this: Attached ImagesA butterfly without wings, is just an ugly bug
Reply:Originally Posted by Magnetic MechanicI take it you are cutting threads up to a shoulder,  which makes that  boring bar impractical.But the other end looks like this: