Tooling and Surface finish

[GeneT45]

112 TPI is pretty slow. Four times slower is not likely. My South Bend went to 227 tpi if I recall correctly.

112 TPI (per your earlier post) is 0.0047" per revolution. I can do 0.0012" - close enough to 4x slower in my book...

GsT

 

[DavidR8]

112 TPI (per your earlier post) is 0.0047" per revolution. I can do 0.0012" - close enough to 4x slower in my book...

GsT

Indeed, my apologies.

 

[Pevehouse]

Just try something "less pointed" if you have it. The diamond tool in your picture is for getting into tight corners.

A picture of your gear setting plate would be handy as well. If that's really 112 TPI, you should be able to go about four times slower, but I've never seen those feed rates expressed as TPI. (For example, my lathe will only cut 60 TPI threads, but will feed as slowly as 0.0012" per revolution (of the chuck).

Feel like you're drinking from a firehose yet? ;-)

GsT

lol, I do but this is all a part of learning and I’m soaking up all I can. Thank you

 

[Pevehouse]

Yea, let’s just say that the 112 was the largest number on my chart so I assume we were feeding as fast as she would go,lol. I will try some different speeds when I get game

 

[DavidR8]

That's likely the slowest feed rate you have. My machine has the max TPI of 112 and slowest feed rate of .0027"/rev

 

[Pevehouse]

That's likely the slowest feed rate you have. My machine has the max TPI of 112 and slowest feed rate of .0027"/rev

I will throw up a picture of my chart when I get home and play with the rates and see what’s going g on there. I’m also learning this lathe as I’m sure you know. I’m in the automotive industry and we used to turn a lot of rotors, drums and sometimes flywheels, so I’m not totally ignorant. This is very different from that though

 

[DavidR8]

I will throw up a picture of my chart when I get home and play with the rates and see what’s going g on there. I’m also learning this lathe as I’m sure you know. I’m in the automotive industry and we used to turn a lot of rotors, drums and sometimes flywheels, so I’m not totally ignorant. This is very different from that though

It's a journey.

 

[Pevehouse]

Here we go. Pictures of my charts. Just noticed the one on the back of the machine that pretty much spells it out for me. Kinda feel like a dumb ass.

 

[Pevehouse]

Am I looking at it wrong or does this still mean that being in E8 is the slowest feed rate?

 

[DavidR8]

Am I looking at it wrong or does this still mean that being in E8 is the slowest feed rate?

Yes, that’s exactly what that means.
Essentially for each spindle rotation, the carriage will advance by the rate at which the selectors are set.
E8 being .0032” per revolution.

One thing to note is that you have separate feed mechanisms for screw cutting and power feeding. The top one is for threading and should only be used for that purpose to save wear and tear on the half nuts and to a lesser extent on the lead screw.
The bottom one is for power feeding.
I believe that the lever directly above the threading chart controls which feed mechanism you are using.