Optimizing cut-directions and order

[lloydsp]

This isn't to share a file, but to share my experience with some router files.

I've been 'fighting the clock' trying to get enough out each day to meet the theme park needs.  So I visited my files with the goal of optimizing the toolpaths.  I started with some 5-shot 'all-fire' plates we make a LOT of.

A LOT of time is wasted just moving between features, so I re-organized the points-list I'm using, and figured that might improve timing.  The goal was simply to minimize the air-cut distance between actual cuts.

It was amazing!  On this one item I'm experimenting with, I've now shaved over 35 minutes off the time to do a sheet.  From 4-hours, 17-minutes, to about 3.75 hours.  I see more improvements.

The method was to get rid of the 'paired' items (always two in a set) that I was using, and go to a single item.  Then, to change the points-list to match the fact that I had only one.  They're not evenly spaced in Y by individual items, only by pairs, because of parting lines between pairs.  So, it was a minor bit of figuring to space the new points-list to match the necessary spacing.

But the savings are great.  And I see more savings to come (as above).

Just a 'note' to try to help others who have actual 'production' work to get out.  It takes a lot of 'tweaking'.

LLoyd

[kvom]

In cases where time is more important than tooling costs it seems that trying to get spindle load to 100% or more is important emphasizing MRR.  As a hobbyist making mostly 1-off parts I tend to baby the tooling, but in a production environment I wouldn't hesitate to break a few endmills trying to cut process times down.

Clearly toolpaths also make a big difference as you're finding.

[Bob La Londe]

One thing I did on a lot of 3D work was to reduce the height of the clearance plain.  On some big jobs it saved me hours.  On simpler jobs it might still save minutes.  

Yes, it will scare the heck out of you the first time you see that cutter raping across your part at 5 hundredths of an inch clearance.  With coolant on you can't even tell if tis going to hit something you forgot about until you hear the snap.  

Its one reason why I have asked if we could have a part clearance height and a MOP clearance height setting. 

[Dragonfly]

And this is the reason I asked some time before for 'item selection order' option in optimization list. Because, frankly speaking, CB optimization is far from good an often does strange rapid jumps while the nearest item is millimeters from the current. Sometimes I make separate identical MOPs just to define the order I want it to move.

[Bubba]

To help with efficiency I often rearrange the entity numbers in Primitive ID's space. It works for me.

[lernincnc]

To help with efficiency I often rearrange the entity numbers in Primitive ID's space. It works for me.

This is interesting.  You also turn off Optimization, correct?  I rearranged primitive ID's with Optimization on and didn't notice any change in the cut order. 

I learned something new today!  Thanks. 

   

[lloydsp]

Yes, Learnin', 

On most of my 'production' designs, I have optimization off, and manually re-order primitives ids to get the most-efficient cuts.

Optimization is great for one-off jobs, but if you do a lot of one thing, you want to save every minute you can.

Lloyd

[lloydsp]

PS,
I should have added that although I have many dozens of .cb designs I occasionally do for customers, about 80% of my day-to-day work is with around 7 or 8 files.  So, it's not that big of a deal to manually optimize them.

Lloyd

[lernincnc]

Lloyd - Thanks for the further explanation.  I'm on this forum everyday and sucking up as much CamBam info as I can.  It's been a huge help.

[Dragonfly]

LLoyd,
I can't recall right now the details but turning off optimization also turned off some other useful features.
I hope David can refresh my memory, please 

[lloydsp]

Fly,
I don't recall seeing any detriment to doing it, once you have a 'finished' design, and are simply trying to minimize the time-to-mill.  But, then, all my production designs are simple 2.5D things.

I'd like to hear David's take on that, though.

Lloyd

[dh42]

LLoyd,
I can't recall right now the details but turning off optimization also turned off some other useful features.
I hope David can refresh my memory, please  

Hello

Yes, it also turn off the start point (start of the cut) ; when optimization is off, the machining of a shape start at the polyline start point (you can use "polyline/start point" to change that). "Cut ordering" is always depth first. With a pocket, the cut start at the external side of the shape instead of in the center. In a MOP that use multiple shapes, the shapes are cut in the same order than the shape selection order.

++
David

[lloydsp]

Ahh!  Well, I also adjust the start-points of my polylines to optimize milling time.  That wouldn't directly affect me.  And since there are no complex pockets or 3D shapes in any of my 'daily' designs, it's pretty simple to manually-optimize a run.  It's all pretty-much straight-line milling or drilling! <grin>

Now, when I'm making molds or other more-complex shapes for a customer, I most certainly DO turn on optimization!

Lloy

[dh42]

Optimization to none is also interesting for text engraving ; in this case, the chars are engraved with the same order they are written in the text object.

++
David

[Dragonfly]

David, thanks for the refreshment!