Turning thread machining time BUG / Overall machining times wrong ?

[gabrielvuelmar]

Threading in fusion turning doesn't give the correct machining time.

CAM Samples > Tutorials > Tutorial6 -> Thread2 timing = 1 sec.

Any changes to RPM doesn't affect timing. Changing machining config doesn't change it also.

Related but not a bug (or maybe):

For some reason I also get very different timings in other machining strategies, machine feedrate is 100%, spindle is 100%. To get the somewhat correct times I had to use 17% feed scale. Machine RPM is not being limited as in file it's using ~1000 rpm and machine max is 3000rpm.

Machine is a brand new US Wheeler LT300A, FANUC control.

EDIT: Removing "Use Constant Surface Speed" gives somewhat an accurate timing with 100% feed scale, even though Profile Finishing for example has only one diameter.

[seth.madore]

The Thread machining time issue is known to us, it's CAM-60782. I've added this thread to the ticket as well.

[gabrielvuelmar]

Hello Seth!

Okay sorry for the duplicate topic, tried to search about it but couldn't.

What about the rest of operations, anything you can add? Maybe I am doing something wrong or the program itself ?


Thanks for your attention.

[seth.madore]

No worries on the duplicate topic, I don't put a lot of trust in our search engine.....

I'm unsure on the machining time for non-thread toolpaths, I always regarded them as somewhat close. I think I've got my mills set to 80% scale and my lathe is somewhere around there as well. It's possible that there are also issues with regular Turning toolpaths and machining time. I'll see if I can find a ticket for those and will let you know.

[gabrielvuelmar]

Yoyo!

just confirmed there is indeed a bug related to Constant Surface Speed.

If you get this example attached, the one using CSS got a smaller time, shouldn't it be a bigger/the same time ?

The only change is CSS disabled, which for this size of part/operation shouldn't change.

[gabrielvuelmar]

Hello everyone!

For anyone going trough  the same issues as me, with fusion machining timing being VERY wrong in turning, and needing to buy yet another program to calculate machining time (even if we paid for fusion to already do that).

I have created a simple application that calculates the machining time of the GCODE.
It's currenty in development, the first version released, as ALPHA, so times might be extremely off for you. If it does so, please reach me and let's make it better.

Right now it does take into account:

G0/G1 modes
G32 Threading cycle
G50 -> Max Spindle speed lock
G96/G97 -> Surface speed mode
G98/G99 -> mm/rev or mm/min

Tool change is set to 10s. 
Spindle Rpm is limited to 3000 or the value you call with G50.
It doesn't take into account machine acceleration, it just adds a delay of ~0.2s per movement.

For beta I am planning a UI, where you will be able to set above variables as well as more options.

To use the app just place a 1001.nc file in the same folder and run it.

I am unsure Autodesk can use any of this, but if you guys want the source code just give me a call, it was built in ~6 hours but should be accurate.

Gabriel Romanzini
Rovuss Performance

[rw_skinner]

Threading time should be fairly simple to calculate since all the variables have been considered already.

Feedrate = RPM / TPI

(Total Length of thread including lead / Feedrate) * Number of Passes = Cutting time

Tool Change time already provided  5 seconds

Rapid Speed is already provided  400 ipm

Distance from end of thread to safeZ is already known

So I'm not sure why machining times can be calculated for almost all other turning but not threading?  It's been a known bug for a long time now.