Been a machinist for awhile and just starting to fool around with gunsmithing. I have a 1949 Winchester model 70 action and last night I noticed there is a Higbee on the receiver threads. Didn't realize that could be done on a manual lathe. Doesn't look like it was done with a file. Maybe done on a mill after the threads were cut.
Anyway, I was impressed!

Higbee cuts weere standard on all fire fighting equipment at least as far back as early 1960 when I served my apprenticeship. It is not a product of CNC

quote:

Originally posted by brad may:
Been a machinist for awhile and just starting to fool around with gunsmithing. I have a 1949 Winchester model 70 action and last night I noticed there is a Higbee on the receiver threads. Didn't realize that could be done on a manual lathe. Doesn't look like it was done with a file. Maybe done on a mill after the threads were cut.
Anyway, I was impressed!

I wonder why this was done to threads that were, for just about any purposes, going to be engaged only once.

I had to look the topic up

Maybe the mechanic who cut the thread was a volunteer fireman

Gentleman


I am curious as to what a Higbee is....


Could you explain or send me a picure of it?



Cal30

quote:

Originally posted by cal30 1906:
Gentleman


I am curious as to what a Higbee is....


Could you explain or send me a picure of it?



Cal30

end thread is tapered to first area of full cross-section to facilitate engaging, and w/o damage.

do a quick search it comes up fast-

https://www.google.com/search?...l0l0l510l510l5-1l1l0



http://firehosedirect.com/prod...e-and-higbee-cut.jpg

Jim
How were they done then. On a mill or a lathe. I've seen some big hollow spindle Lehman's with a thread kick out that could do it on oilfield connections.
They have been on fire hose connections forever.
Also is this standard on most rifle actions?

quote:

Originally posted by brad may:
Jim
How were they done then. On a mill or a lathe. I've seen some big hollow spindle Lehman's with a thread kick out that could do it on oilfield connections.
They have been on fire hose connections forever.
Also is this standard on most rifle actions?

Beats the $hit out of me!

And Hydrill connections always want both steps in the same place. What a pain in the ass!

I have seen it done on a CNC. I have created them on an engine lathe, but not with the power on. Change your threading tool for one that is flat and parallel to the bore( a piece of Rex95 with slight modifications to make it pretty works perfect). There is no need for rake or relief angles as everything is done slowly.

Disengage feed and put chuck in neutral. Locate the tool so it will cover the area necessary to create a full width thread. You will be making movements of about a half rotation. Increase depth of cut by .0015-.0035 each time until full thread width is accomplished.

I have also seen those with much more experience and better reflexes than I had perform this procedure with the power on.

Hope this helps.

I'm probably imagining something that isn't possible and not encountered at all when cutting these; however- how do you end up without a step in the thread where the tool stops?

and-

does this thread require a matching Higbee cut to engage or will it fit its male/female counterpart without that piece being similarly threaded?

thx

As you approach full width you slowly withdraw the tool. That keeps there from being a sharp step.

Best way to learn about this is to make a copy of the picture and go out to your lathe and play. Get a piece of 1"crs thread it say 12TPI and then play around. Without removing it from the chuck see what you can do. When the light bulb comes on it is amazing, you're probably going to at the very minimum chuckle a bit.

Yes it will line up with the other thread whether they are higbeeized or not.

Many if not most of the later machine-made 19th century arms had their first receiver thread treated in this manner, i.e. relieved to full ID. For instance Winchester and Marlin rifles were/are constructed this way but not Mausers.

Makes rebarreling a lot easier since there's no need to relieve the last thread on the new barrel tenon. FWIW at Trinidad we were taught to perform this thread relief on Mausers as SOP, to ease rebarreling. Even had a specially-L-shaped lathe tool for the job, one of the first specialty tools I ever ground.
Regards, Joe