Picking up thread

[Riesel]

When you are picking up existing thread to continue, do you cut new threads using the 30 degrees on the compound or do you turn in cross slide? I hope I asked this question in a manner that make sense

 

[Sniperhandle]

When you are picking up existing thread to continue, do you cut new threads using the 30 degrees on the compound or do you turn in cross slide? I hope I asked this question in a manner that make sense

When you are trying to line it up, Using the compound is necessary to get it perfect. Engage the half nut then shut off lathe with it still engaged, Make sure to take up backlash, Then use an Opti Visor or a magnifying glass with a white piece of paper under the threads to get it lined up by using the compound. It's easy once you've done a couple times.

 

[Walt Krafft]

After it is picked up, just use the cross slide to cut it deeper.

 

[Lead Slanger]

Once it's lined up, you can do either.

 

[LVLAaron]

Either, really.

But when finishing threads, the final few thou I do with the cross slide to get a full cut on the right side of the thread - that's the side holding torque.

 

[Riesel]

Got it lined up as per instructions and added about .9 " of threads to this Savage barrel (rechambering a 7RUM to 7SAUM.) barrel nut went on smooth as butter and as soon as reamer gets here I will finish. I'm looking forward to shooting this caliber.

 

[Hal]

When cutting a thread using the compound,that's set at 29 1/2*.
You use the cross feed the last pass or two, to cut on both sides of the thread.
This makes the thread a true 60* instead of 59*

Hal

 

[LVLAaron]

When cutting a thread using the compound,that's set at 29 1/2*.
You use the cross feed the last pass or two, to cut on both sides of the thread.
This makes the thread a true 60* instead of 59*

Hal

Bingo

 

[Sniperhandle]

When cutting a thread using the compound,that's set at 29 1/2*.
You use the cross feed the last pass or two, to cut on both sides of the thread.
This makes the thread a true 60* instead of 59*

Hal

I quit using the compound to cut threads on these little threads we do on guns, If I was cutting something like 6TPI or maybe 8 TPI I would use the compound for that, But the shallow threads it isn't necessary. I advance my cross slide then zero out my DRO and then take my cut, Back out and go back to zero, Add in my next cut and then zero the DRO.
Plus I leave my compound on 45 degrees because I use 45 a lot, Saves time and wear and tear on the compound studs, rather than changing it all the time.

 

[DaveTooley]

"Picking up an existing thread."
turn the compound parallel to the bore
engage the half nut and run the tool midway up the threads
stop lathe, do not disengage the half nut
place a paper towel under the treads for definition
look at the tool under some form of magnification, anything will do
feed the compound and cross feed in until you have the tool lined up with/in the existing threads, favor the trailing face of the threads, zero the cross feed and the compound
back the cross feed off a few thou and take a trial cut
gradually feed the cross feed until it starts to cut and adjust as needed.
Again err on cutting the trailing face.
Feed in with cross slide not the compound
Easy Pee Zee

 

[Hal]

What size is your lathe ?
I know some of guys that have a smaller lathe that are not as rigid cut threads using 291/2*. Using one side of the cutting tool puts less
load on a light duty lathe.

Hal

 

[Sniperhandle]

What size is your lathe ?
I know some of guys that have a smaller lathe that are not as rigid cut threads using 291/2*. Using one side of the cutting tool puts less
load on a light duty lathe.

Hal

1340
But I do it my 12x36 too and it doesn't mind at all.

 

[GenePoole]

I just set one back for a Panda action. I always do it just like I would a standard thread: 29.5° on the compound. It's easier to get things lined up with the compound 90° to the cross-slide, but easy rarely equals correct.

You have to work both the compound and cross-slide incrementally until you get it all correct, then back out the compound only, advance to the new non-threaded area, touch off with compound only, then thread like normal.

Cut back the shoulder:

Scratch pass:

Thread away:

All done. Check over wires or with thread mic:

Cut back to original tenon length:

Recut the cone:

Check cone:

Rechamber:

 

[jackieschmidt]

Since I always thread straight in, I guess my answer would be to use the cross slide after you catch the thread.