MACHINE SHOP TIPS #18 Musing on Lathe Threading tubalcain

Tubalcain explains why he sets the compound to 29 degrees for threading. Also how to realign the tool with the work after losing his place.

Category:

Science & Technology

Tags:

• bridgeport
• mill
• south
• bend
• lathe
• atlas
• clausing
• delta
• logan
• hardinge
• rockwell
• starrett
• steam
• engine
• stirling
• john
• deere
• ridgid
• toledo
• ream
• tapered
• threads
• lufkin
• micrometer
• caliper

[terrywerm]

I learned machine shop practice from a very good high school shop teacher, who, like you, was what I call a 'true teacher'. 'True teachers' are those who take the time to teach simply because there are those who wish to learn from them. You take so much time from your retired life to continue teaching those who wish to learn, and you are a true credit to your profession. Your videos have been great refreshers as I have gotten into hobby machining. Keep up the great work, it is much appreciated!

[mrpete222]

@terrywerm Thanks for your very great encouragement!!!!

[refa42]

@mrpete222

Acme threads sounds great. But after this one I would rather see bunch of clips in series of you doing stuff in or outside the shop that you enjoy doing. Without the teaching part. That's because of long row of detailed videos and now this serious business of processing feedback that you shouldn't have received in the first place.

[swallin19]

On the permanent engagement this is widely taught in Europe and some lathes have no dial fitted, tool retraction, or lift, is used during reverse to clear the thread. Rarely done by Home Machinists is single point chasing, delightfully controllable method for ultra fine finish, and any pitch can be cut if you have a master. We were instrument makers and used a 4:1 masters and made custom fit threads, no tolerance, they were made to feel right on assembly for focussing threads in lenses.

[swallin19]

Sometimes it is obvious a method works, without realizing that other countries do it another way, British machinists had never been shown this method before the war!! South Bend were one of the rare makers who published methods, and taught the US way of cutting threads with set over.

UK method is straight plunge, both faces cut in traditional method. The end result is the same as at full depth both sides touch. In Swiss precision practice straight is used, as Chasing is more widely used.

[BMWHP2]

Perfect explenation, good teacher and nice instruction video,

Thanks a lot Sir

[gmcallsuk]

Superb videos, I feel very nostalgic whilst watching them, as these are the exact methods to thread on the lathe shown to me my my mentor 30 years ago when I was an apprentice. The guy I learned with has sadly passed on and I really miss him. Oddly enough I feel he is still not too far away watching over my shoulder me complete all the the tasks him and myself did all them years ago. Still learned a little tip using the blue as we just used a nut to test when coming down to the money on size.

[WalneySkyland]

Don't just slam the gearbox into reverse... have the cross slide set to zero all the time and as you get to the end of the cut wind out at hte same time you declutch then reverse it and before you put the next cut onto the compound simply remember to wind the cross slide back in to zero and carry on as you would normally. Given sufficient practice it becomes as much second nature as any other method I was quite shocked when you just slammed it into reverse like that.

[par4par72]

Take it from someone who used to single point 0-80 coiling mandrels for Heli-Coil. this is proper technique and optimal. you can NOT SP thread 0-80x3" using any other method and hold .0002!!! END OF STORY!