Telescoping Jack Screw - FINAL PROJECT

The diameter of your work piece has to be able to fit into a 5C collet but basically yes, you would put the collet in the hex-shaped block and lock it in place in the vise. Then you cut one flat, turn the block and cut another flat and so on until all six flats are cut.
I like show and tell. When I'm in the shop I see it happening.

Edit: When I asked about the 5C collett it was because I got the distinct impression there would be a milling task to complete on the lathe and if it's in the description I missed it.
 
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hey guys, I'm not starting internal threading yet, but I want to keep it in the back of my mind. my teacher said drill bit 1/16 smaller and bore it .005 bigger than the minor dia. is this the minor diameter of the thread pitch (using 1-10 threads). Thanks!

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is this the minor diameter of the thread pitch (using 1-10 threads).
With my limited knowledge of single point thread cutting I'll say yes.

Edit; Was this a trick question? The print shows 1-8 UNC.
 
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It has been changed to 1-10 UNS, sorrY!! I mentioned it in my last question. So Mikey it is minor pitch diameter then...or just the actual Minor diameter of the thread itself?
 
It has been changed to 1-10 UNS, sorrY!! I mentioned it in my last question. So Mikey it is minor pitch diameter then...or just the actual Minor diameter of the thread itself?

Okay, so 1-10 UNS. The process is the same. Go here and find the 1-10 UNS specs. Look at the tolerance range for a 2b (class 2 internal) thread and note that the larger end of the minor diameter range is 0.913". Adding 0.005" to that gives you a bore of 0.918". That hole should allow a 1-10 2a external thread to fit if the thread is within the tolerance range for that thread. So yes, the ID of that bore will be your minor diameter.

http://www.diecasting-mould.com/dat...t-Screw-Socket-Thread-Specification-Sheet.pdf
http://www.diecasting-mould.com/dat...t-Screw-Socket-Thread-Specification-Sheet.pdf
Pitch diameter is the mid-point between the major and minor diameters so no, we aren't talking about that.

Hmm, let me see if I can simplify this. When you turn your external thread it will have crest dimensions that have to fit into the female root dimensions with adequate clearance, while also allowing adequate engagement on the flanks of the thread, right? Your instructor is giving you a method that allows you to provide a little clearance at the interface between the root and crest of these threads so the two threads will fit without contact at those points. Did that clarify or muddy things up for you?

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THIS IS WHAT I GOT DONE TODAY.
Drilled with the .500 drill about 1 inch in. Then drilled with the 57/64 drill. Worked pretty well and cut pretty good. Don't have updated pics, this was taken before lunchtime but I got both sides done! They look awesome, I hope I can internal thread. My plan is to cut each piece off and grip on the knurled end. Then just run the internal thread tool completely through the part. Others have internal threaded to a shoulder, but I want to avoid that when this is my first internal threading exercise. Sound like a plan? Thanks guys!

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Threading internally more than about twice the thread diameter is chancy. You'll get spring on a long enough tool to reach that far through the double piece.
You might try internal threading to a shoulder on a piece of scrap before you start the final pieces.
 
Unfortunately made a simple error today and cost me 10% of my grade on this project. Granted, I could do another one in a day based on my experience now, but it was a lot of work to mess up on the cutoff part of the procedure. My little end knurled is off by .010 and my total length is off by about the same. The sad thing is the knurled length had a tolerance of .010 and the length itself overall had a tolerance of .030. I believe my error was indicating the length on my lathe, then going back to the grinder and making sure the tip of my cutoff tool was sharp. Either way I messed up and it's 10% of my grade, but I have to worry about getting the other parts done because the Very Top Cap and the Top Ball part are due this Friday! I need some assistance.

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