Buttress Thread Cutting Tool, Would Like To Borrow...

[Richard White (richardsrelics)]

In the old days you just timed it right....and you were quite jumpy when it got close to the end..LOL The grove kind of weakens the shaft, especially being hollow, so you want to leave that material there. It is also possible to set up a system that automatically remove the tool at the same point each time...

 

[T Bredehoft]

In an industrial setting its quite possible that thread was milled, not chased.

 

[gi_984]

Or ground.

 

[Richard White (richardsrelics)]

Well, broke down and called MSC, Elkhart Indiana store had 8 inserts and agreed to sell me just one. I am gathering that this particular thread is some form of modified Buttress thread, as the pitch is .071 and it has a flat at the bottom of the thread that is nearly .03 wide. So I got my handy dandy diamond impregnated carbide sharpening wheel out and placed a .03 flat on either end of this tool.
I will know in a day or two how it turns out...

 

[4GSR]

In my past 35 years, I've dealt with nearly 50 different variations of Buttress threads in the line of design work that I do for a living. And only two or three are of the National Standard Buttress thread form. There are literally hundreds of different thread forms used in the design of oil field equipment used today. Some of them I've seen will blow your mind to wits end, and the only way they can be cut is using a CNC machine. One example is a thread with a variable pitch that changes constantly for the length of the thread. And along with that, throw in variable width and depth of the thread for the length of the thread. There's more to the thread than that, just a bit to share.