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View Full Version : OK maybe this was too aggressive even for Adaptive Clearing ;)



Washout
03-01-2017, 04:06 PM
Happy New Year all,

A quick video of some aluminium work, where I pushed adaptive clearing a bit too far. Parameters were DoC 15mm, stepover 3.2mm optimal.

Interestingly it was the spindle that overloaded and shut down rather than chip weld or the usual horrors..


https://www.youtube.com/watch?v=HaTaT9KYvs0

JAZZCNC
03-01-2017, 04:44 PM
Ouch.!! Yes touch aggressive.

Just Did test to see what i-machining would spit out for same material and cutter/flutes etc at it's most aggressive setting which is level 8.
So for simple circle pocket 15mm DOC gave 16810rpm 3769 feed 1.970mm stepover.

Level 3 or 4 is what I normally run at.
Level 3 12878rpm 2117 feed 1.116 step
level 4 13431rpm, 2233 feed 1.550 step

What feeds and RPM was that.?

Clive S
03-01-2017, 04:48 PM
Its good to see cockups (we all make them) well at least the cutter didn't break:yahoo: What was the RPM?

Washout
03-01-2017, 04:51 PM
Ah thanks for that Dean, I'll retry with level 3 and see if that works. It should work as it wasn't the usual chip weld, but rather the spindle went into "DU" which is an Amp overload iirc

My F&S's were F2760mm/min and 17,642rpm - GWizard generated with HSM and roughing options checked.

The whole video (once I've finished editing) has 6 and 4mm tools cutting fine with similar strategies - the 6mm was at 10mm DoC, which was frankly astounding considering previous experience.

njhussey
03-01-2017, 04:56 PM
As Clive says, nice to see cock ups as well as triumphs.....I like the way the sacrificial bed moves to save the cutter when the spindle overloads :biggrin:

JAZZCNC
03-01-2017, 05:00 PM
Ah thanks for that Dean, I'll retry with level 3 and see if that works. It should work as it wasn't the usual chip weld, but rather the spindle went into "DU" which is an Amp overload iirc

It will work because level 3 isn't over aggressive. But Even at that speed scares the crap out of me when goes flying around into corners etc and more chance catching shooting Star than hitting E-stop before tool breaks when shit hits fan.! ..:cower:

Clive S
03-01-2017, 05:02 PM
As Clive says, nice to see cock ups as well as triumphs.....I like the way the sacrificial bed moves to save the cutter when the spindle overloads :biggrin:

Eyes like a SHrat:devilish:

JAZZCNC
03-01-2017, 05:11 PM
I like the way the sacrificial bed moves to save the cutter when the spindle overloads :biggrin:

To be honest I think that would have contributed to the stall slightly because if you watch carefully it starts moving around soon into the cut and because the cut was so aggressive was pulling material into the cutter increasing the step over.
When first watched saw that straight away and first thoughts where it had pulled into cutter but after checking i-machining can see it was bit aggressive but just for laughs think I'd try again with stiffer setup.

Washout
03-01-2017, 05:11 PM
As Clive says, nice to see cock ups as well as triumphs.....I like the way the sacrificial bed moves to save the cutter when the spindle overloads :biggrin:

All in the cough....design...cough cough ;-)

njhussey
03-01-2017, 05:19 PM
All in the cough....design...cough cough ;-)

Good safety feature :victorious:

Chaz
03-01-2017, 05:23 PM
Happy New Year all,

A quick video of some aluminium work, where I pushed adaptive clearing a bit too far. Parameters were DoC 15mm, stepover 3.2mm optimal.

Interestingly it was the spindle that overloaded and shut down rather than chip weld or the usual horrors..


https://www.youtube.com/watch?v=HaTaT9KYvs0

What is the spindle rating? I was surprised the endmill did not break when the machine was still moving later. The whole 'wood' area moves but the endmill remains, incredible.

Washout
03-01-2017, 05:31 PM
Hi Chaz - that was the 2.2KW water-cooled variant.

As Jazz says if the bed was moving and allowing the cutter to take more than the desired 3.2mm then that might account for the spindle cut out. I've generally found that 8mm tools tend to survive very rough treatment, whilst 6mm and below don't. Last time I used an 8mm when something went wrong it welded itself into the plate and the machine then started walking itself off the table under spindle power, which was pretty scary, but the tool stayed intact.

I was even more grateful this time that the part wasn't ruined as I'd just finished cutting on the underside (hence the 4 hold down screws). This was the "cut out" toolpath in essence.

JAZZCNC
03-01-2017, 05:32 PM
What is the spindle rating? I was surprised the endmill did not break when the machine was still moving later. The whole 'wood' area moves but the endmill remains, incredible.

Wood moving was the only reason endmill was saved he's lucky lucky boy . .:greedy_dollars:

Chaz
03-01-2017, 05:44 PM
Hi Chaz - that was the 2.2KW water-cooled variant.

As Jazz says if the bed was moving and allowing the cutter to take more than the desired 3.2mm then that might account for the spindle cut out. I've generally found that 8mm tools tend to survive very rough treatment, whilst 6mm and below don't. Last time I used an 8mm when something went wrong it welded itself into the plate and the machine then started walking itself off the table under spindle power, which was pretty scary, but the tool stayed intact.

I was even more grateful this time that the part wasn't ruined as I'd just finished cutting on the underside (hence the 4 hold down screws). This was the "cut out" toolpath in essence.

Awesome.

As soon as I get my misting system working on my little Denford, I want to do the same. I am however limited to about 4400 RPM via a 1.5KW AC Servo, so my level of adaptive is not the same but Im keen to see how far I can push.

JAZZCNC
03-01-2017, 05:53 PM
Awesome.

As soon as I get my misting system working on my little Denford, I want to do the same. I am however limited to about 4400 RPM via a 1.5KW AC Servo, so my level of adaptive is not the same but Im keen to see how far I can push.

Use larger cutter if possible and you'll stand more chance. Smaller cutters need the high rpm and will fail quickly if run with low rpm at high feeds.

Chaz
03-01-2017, 06:13 PM
Use larger cutter if possible and you'll stand more chance. Smaller cutters need the high rpm and will fail quickly if run with low rpm at high feeds.

Currently use 8mm roughing and 10mm finishing end mills. I think Ive got a 10mm roughing one I can try.

Chaz
05-01-2017, 05:09 PM
Use larger cutter if possible and you'll stand more chance. Smaller cutters need the high rpm and will fail quickly if run with low rpm at high feeds.

So I managed to get one set of cuts done and then snapped an 8mm roughing mill on the 2nd try.

Just uploading the vids now.

Chaz
05-01-2017, 05:43 PM
https://www.youtube.com/watch?v=j0wJN9qsw8k

Details there, 4K RPM, 1250 mm/min, 3 flute 8mm roughing mill. DOC 10mm, WOC 1mm.

Chaz
05-01-2017, 05:47 PM
https://youtu.be/qAum2f3zJI8

And then failed attempt. Surprised by the endmill snapping. Expected more but I am severely limited by RPM. Sorry. the Youtube info isnt shown unless you watch it there but its at 1500mm/min.

JAZZCNC
05-01-2017, 07:41 PM
And then failed attempt. Surprised by the endmill snapping. Expected more but I am severely limited by RPM. Sorry. the Youtube info isnt shown unless you watch it there but its at 1500mm/min.

That looks like drove the tool into material on positional move rather than trying to take cut. Did you simulate the toolpath to check for any crashes.?

Chaz
05-01-2017, 09:05 PM
That looks like drove the tool into material on positional move rather than trying to take cut. Did you simulate the toolpath to check for any crashes.?

Its the same path as the previous cut. The first one was done a bit slower. The stock dimensions are less than what was programmed, that's why it cuts a bit of air but it does look like it 'plunged' but it did path is the same cut as the first vid (just reset the zero and went again).

Chaz
05-01-2017, 09:07 PM
I think I have another 8mm roughing mill. Will setup a toolpath that that goes around the square with constant contact and see how that works.

JAZZCNC
05-01-2017, 11:52 PM
Its the same path as the previous cut. The first one was done a bit slower. The stock dimensions are less than what was programmed, that's why it cuts a bit of air but it does look like it 'plunged' but it did path is the same cut as the first vid (just reset the zero and went again).

But did you move the stock so it thinks in different place or possibly didn't zero Y axis exactly right because to me it looks like it's doing positional move and thinks stock edge is in different place to where actually is. The fact the tool path retract distance when moving is so close doesn't allow much room for error.!

Chaz
05-01-2017, 11:55 PM
But did you move the stock so it thinks in different place or possibly didn't zero Y axis exactly right because to me it looks like it's doing positional move and thinks stock edge is in different place to where actually is. The fact the tool path retract distance when moving is so close doesn't allow much room for error.!

Nope. Just Z. I'll do another on the weekend.

Washout
07-01-2017, 12:21 PM
Hi All,

Just as a way of update from the OP here are two related videos - one for Fusion 360 CAD/CAM and one for the entire cutting job, with successful adaptive clearing using 6 and 4mm 3 flute roughers @ 10 and 5mm DoC respectively:


https://www.youtube.com/watch?v=Y5FGzQ66stM


https://www.youtube.com/watch?v=4Fpve-cjTSc

Hopefully the more aggressive cutting has me off of the "cruelty to cutters" watch list ;)

Chaz
07-01-2017, 12:33 PM
Hi All,

Just as a way of update from the OP here are two related videos - one for Fusion 360 CAD/CAM and one for the entire cutting job, with successful adaptive clearing using 6 and 4mm 3 flute roughers @ 10 and 5mm DoC respectively:


https://www.youtube.com/watch?v=Y5FGzQ66stM


https://www.youtube.com/watch?v=4Fpve-cjTSc

Hopefully the more aggressive cutting has me off of the "cruelty to cutters" watch list ;)

Awesome, nice result there.

Washout
07-01-2017, 12:43 PM
Thanks Chaz,

I need to add in some single flute cleanup passes for the scalloping the adaptive cutting leaves, but it came out nicely for what I need it for.

JAZZCNC
07-01-2017, 09:21 PM
Looking good but when that really usefull guy shows up tell him the noise isn't the bed moving or hard/soft spots it's the tool rubbing because the Adaptive stepover is little aggressive for that portion of the Arc where it goes from Thin to Thick or vise versa. ( you'll notice it's always in corner or tighter Arcs)
I get the same noise with i-machining and it's why I don't go so aggresive on the stepover. Having more coolant will reduce the noise, mostly because lowers the rubbing affect, but lowering step over is best if doing it in lots of areas.

It's an horrible noise that scares the shite out you because like feels playing russian roulet with cutter.!!!