Gunsmithing Internal threading help

[dcp2]

In South bend - How to run a lathe

For external threading it says to set the com-pound rest to29 degrees to the right. Says nothing about internal

So I am watching a YouTube video and the guy says for internal threading you set the com-pound to 29 degrees to the <span style="color: #FF0000">Left</span>

I know people set the com-pound to 29 29.5 and 30 degrees

So what do you guys do for Internal threading

Thanks

 

[300sniper]

Re: Internal threading help

it do it they way you say the video described.

 

[RADcustom]

Re: Internal threading help

It would depend on which way the tool was designed to cut.

 

[LRI]

Re: Internal threading help

For me I like the tool on the +X side of the part. This way I can see everything going on and the chip goes down instead of up. It requires you to mount the tool upside down though on your holder. Set your compound @29* just the way you normally would and run it.

C.

 

[dcp2]

Re: Internal threading help


So one would set to internal tool to cut on center on the inside or-x side.
Then just turn the tool over and thread the opposite side or +x
Thanks


<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C. Dixon</div><div class="ubbcode-body">For me I like the tool on the +X side of the part. This way I can see everything going on and the chip goes down instead of up. It requires you to mount the tool upside down though on your holder. Set your compound @29* just the way you normally would and run it.

C. </div></div>

 

[hero's machine]

Re: Internal threading help

It might make it easier if you picture the situation in your head...

You are making sequential cuts that need to end up at a 60* vee. You are trying to work one edge to keep backlash from hosing you and make life easier on the cutter. The tool needs to follow the thread and stay "loaded" against the leadscrew and be advanced deeper into the cut, which can be accomplished by following one edge of thread. Just visualizing it will help. It won't matter if you feed in or out, near or far.....just follow the principal.