incorrect Machining Times

[GRAEMESUQ2Y]

Hi 

Ive been using fusion 360 for over a year now and have recently started using the cam machining , I have found that the machining times stated are not correct. I have found this mainly in the drilling operations where each operation has in unrealistic machining time .

This was using the default 30m per minute 100% . 

I have also activated the Manufacture Preview in Preferences and created a machine with all feeds given a rapid traverse value for all axis.

Please can you advise if there is something I am doing wrong or is there a work around to solve this problem.

Regards Graeme scott

[paolo.bastianelli · Accepted solution]

Hi @GRAEMESUQ2Y !

First of all, unless a software is actually simulating G-code, there is no way for it to be spot-on with machining time. There's quite a few aspects that Fusion 360 won't be aware of (exact time taken for tool changing, for moves in between a toolpath and another and so on), but in your case I believe the discrepancy in the machining time for drilling is mainly due to the fact that, when you assign values for the feed and the rapid, the software will consider that value applicable for ALL the relevant segment, whilst in reality the machine will take some time to accelerate/decelerate to/from that value in every segment. I'd also make sure your post applies the correct rates after post-processing your toolpaths. Normally I wouldn't expect the difference between stated and actual machining time to be more than 20/30%, but you have to keep in mind that in general, anyway, the machining times that Fusion 360 gives are just an indication on what to expect on the machine.

I hope this helps, have a good Friday! 🙂 
Paolo