QCTP too tall

[chris.epp]

Is this practice or the real deal? Just wondering. If practice experiment. Start with 150 RPM. First pass just do a witness cut so you can verify threads are correct. After that try .005 per side first few passes. Then taper off. The last couple of passes take .001 and do a spring pass.

You will be able to tell off the pass s too heavy.

FYI. This is just my experience. It does not matter if you plunge straight in or set compound at 29 or 30 degrees. I find I like going straight in as it is easer to get my desired depth straight away.

You will find your preferred method. Take what people suggest and incorporate what make best sense to you.


Cutting oil is my blood.

You are referring to the thread cutting? I'm talking about just turning down the stock to size first.

 

[twhite]

Yes thread cutting. Just experiment. Start around 500 rpm and adjust from there. Depth of cut will depend on your cutter geometry. Start light like .020 and adjust from there.


Cutting oil is my blood.

 

[chris.epp]

Yes thread cutting. Just experiment. Start around 500 rpm and adjust from there. Depth of cut will depend on your cutter geometry. Start light like .020 and adjust from there.


Cutting oil is my blood.

What about width of cut. How much carriage should travel per revolution?

 

[twhite]

How about you start at 760 rpm .003 feed rate and .020 per side depth cut to start. That should get you rolling.


Cutting oil is my blood.

 

[twhite]

Also looking at your picture. You have a bunch of chatter at the start of your cut.

Please check cutter is on center, is the cutter sharp? Is the live center fully engaged? Is the compound snugged down? Make sure when you cut that you dial into the part. If you dial it back even an iota that is not good.


Cutting oil is my blood.

 

[chris.epp]

Also looking at your picture. You have a bunch of chatter at the start of your cut.

Please check cutter is on center, is the cutter sharp? Is the live center fully engaged? Is the compound snugged down? Make sure when you cut that you dial into the part. If you dial it back even an iota that is not good.


Cutting oil is my blood.

I don't think that was chatter, the end of the rod was pretty beat up I think that was residual that was not cleaned off yet? The cut you recommended starting with happened to be what I had tried. It's a very light cut. (The material coning off is like aluminum very fine thread). It squeaked occasionally closer to the chuck as it went on. Didn't sound like chatter but squeaky. What would cause that? Also, what kind of depth of cut when all is going well would you expect an a 10x22 bench top lathe to be capable of doing? I have no idea what would be considered reasonable.

 

[twhite]

My suggestion is. Try going deeper each cut until the lathe does not like it. It is very hard to give more accurate info without being there to see how it is actually cutting and hear it.

If you want to cut faster. Go with .006 or more on the feed and try .100 depth cut see if the lathe likes that. Finish will suffer.

Remember we all have to learn on our own how our particular machines perform. No amount of book reading and studying will ever replace time on our machines. It takes untold hours depending on each individual to get to a proficient level.

It is a hobby so take your time and enjoy it. Remember failure is moving forward in your skills.


Cutting oil is my blood.

 

[chris.epp]

My suggestion is. Try going deeper each cut until the lathe does not like it. It is very hard to give more accurate info without being there to see how it is actually cutting and hear it.

If you want to cut faster. Go with .006 or more on the feed and try .100 depth cut see if the lathe likes that. Finish will suffer.

Remember we all have to learn on our own how our particular machines perform. No amount of book reading and studying will ever replace time on our machines. It takes untold hours depending on each individual to get to a proficient level.

It is a hobby so take your time and enjoy it. Remember failure is moving forward in your skills.


Cutting oil is my blood.

Hahah, I feel like a dolt. I was doing a .003 cut not .03. I had to run out but did a .015 pass quickly and it was easy clean cut. So I'll try the .03 when I can get back. Thank you very much for all of your time ans guidance. My time is frustratingly limited so can only spend small bits of time at the moment, but the little bit I've done shows how decievingly simple it is. At its core it's a basic process, but wonderfully complex in the myriad of details all involved in the process, and I have yet to even scratch the surface. Very satisfying. I look forward greatly to this journey.

Oh, that is a dead center, I need to order a live center.

 

[twhite]

Haha. Glad you caught that one. You will get it for sure. Just make chips and have fun.


Cutting oil is my blood.