I got a D for effort! An actual application for non-circular boring/turning

[skunkworks]

Been busy - so not much time to tinker... But finally had the time to do a proof of concept for the x axis ball nut assembly.

[eKretz]

Thanks for clearing that up about the nail polish. I was worried about you for a minute. Now at least I'm a little bit less worried. 😁

[RB211]

You know clear nail polish exists

[RMinMN]

You know clear nail polish exists

In my world it does exist and it takes a 40 mile drive to get a little bottle because it isn't a stock item. Hot pink is a stock item in this house.

[skunkworks]

You know clear nail polish exists

I actually stole my daughters clear nail polish - it was crap. It would start pealing off in a day. So I tried the red nail polish. Its color is 'pucker up' if anyone is interested.. It seems to last a long time.

sam

[RB211]

I actually stole my daughters clear nail polish - it was crap. It would start pealing off in a day. So I tried the red nail polish. Its color is 'pucker up' if anyone is interested.. It seems to last a long time.

sam

Well, good job on the D bore, that is pretty cool. I think another way you could do it is stop the spindle and move Y to cut the flat and resume. Pretty neat how you did it with the spindle still rotating

[DR]

I like programming oddball operations like this. Can your machine run faster to get the cutting speed up a bit?

I'm currently retrofitting an Emco mill with Centroid Acorn and will have the spindle driven by a servo to do the same type operations although I can't think of many practical applications.

[skunkworks]

I like programming oddball operations like this. Can your machine run faster to get the cutting speed up a bit?

I'm currently retrofitting an Emco mill with Centroid Acorn and will have the spindle driven by a servo to do the same type operations although I can't think of many practical applications.

I am limited by the acceleration of the machine.. Kinda works like this

Read spindle encoder -> Figure spindle position based on encoder and index -> calculate the x/y postion based on the shape and tool diameter -> move the x/y axis to correct location -> repeat 1000 times a second.

So - to follow the shape - the machine has to be able to keep up to the calculated position based on the spindle.

I can run it faster and I should calculate the calculated position vs the actual position to get a following error. Just haven't gotten to it.

sam

[DR]

I'm sure somewhere I saw a video of a CNC lathe (Okuma?) that was able to turn camshafts and other non-round objects at normal high rpm cutting speeds. The process involved the x axis moving in and out rapidly. under servo control. Apparently the control could handle it.

[skunkworks]

I'm sure somewhere I saw a video of a CNC lathe (Okuma?) that was able to turn camshafts and other non-round objects at normal high rpm cutting speeds. The process involved the x axis moving in and out rapidly. under servo control. Apparently the control could handle it.

Currently the control isn't the limitation. The acceleration is the limiting factor. Plus it doesn't do any trajectory planning.. I made it a bit better by adding small radiuses to the corners so the transition wasn't so abrupt. I really should have it calculate following error to get a feel for it.

I mean - I could run it faster I just don't know how well it will follow the path.

sam

[Dan Dubeau]

Very cool, that's pretty impressive!

[Doozer]

Polygon turning.

-Doozer

[polaraligned]

This is awesome. I assume it was hand G-coded.

[Mcostello]

As a machinist something We all need to relearn occasionally is "good enough is sometimes good enough."

[skunkworks]

As a machinist something We all need to relearn occasionally is "good enough is sometimes good enough."

Did I miss something?