Hello Guest it is March 29, 2024, 11:49:50 AM

Author Topic: MACH3 spindle behaviour  (Read 4258 times)

0 Members and 1 Guest are viewing this topic.

Re: MACH3 spindle behaviour
« Reply #10 on: May 06, 2018, 06:45:46 PM »
Hi,
my experience which I doubt is unique was that I spent a lot of time getting speed just right,
FWD/REV etc only to find that I don't really need it.

Do you have any LH mill tools or drills for instance? When using my high speed spindle for routing (24000 rpm)
I just set to max speed and leave it there. If I could make it go faster I would.

Occasionally when doing aluminium I'll drop it to 15000 rpm, give or take...its not that critical.

When I'm doing steel or stainless I use my high torque spindle. Its based on a kick arse AC servo. I've got great
control over it but again I don't need it most of the time, within 10-20% is good enough.

My recommendation is don't get to hung up on spindle speed unless you have to for some reason. You may find
as you spend more time making chips that other matters become more important. In my case its coolant
for steel and stainless, much more important than spindle speed.

Craig
'I enjoy sex at 73.....I live at 71 so its not too far to walk.'

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: MACH3 spindle behaviour
« Reply #11 on: May 07, 2018, 02:28:59 AM »

Is there a particular reason you need really accurate speed? In most cases you just set the speed, often as fast as it will go, and leave it there. Who really
cares what speed it is?

Craig

That is a very odd statement to make i think - speed and feed are critical in most cases. If you have a tool that needs 35,000rpm and you only have 24,000 then its going too slow and allowances must be made or it will break - if you don't know or care what speed it is doing, how do you compensate. On a 20mm tool you can get away with slightly wrong chip load but at this speed it will be small tool and even a little runout can be enough to break it. ;)
Re: MACH3 spindle behaviour
« Reply #12 on: May 07, 2018, 07:21:01 AM »
Hi,
my spindle can do 24000 max, I have to set feeds to match. If my speed was out by 10% then  my chip load would be out by 10% as well...so what, I'm never that close to the absolute limit.
With the small tools I often use I would like to go faster but I can't and I'm not spending the bucks to do it either. The job will complete somewhat more slowly at 24000 but it will complete
and I'm happy.

Likewise with my high torque spindle (max 3500 rpm, 6Nm cont) if my feeds and speeds are within 10-20% of theoretical best that usually enough.

Back in the old days before CNC that old Bridgeport had a number of  ratios, you selected the speed closest to what you required and got to work. Are you trying to tell me that all those jobs I did with manual mills and
lathes were compromised because I did not have the exact speed ratio available? Of course not, provided the surface speed is within 20% of the recommended for that material you can always find a feed that worked well.

I have found that using pressure coolant to clear the cut zone of chips to be a bigger determinant of success than having the exact speed and feed.

Craig
'I enjoy sex at 73.....I live at 71 so its not too far to walk.'

Offline ger21

*
  • *
  •  6,295 6,295
    • View Profile
    • The CNC Woodworker
Re: MACH3 spindle behaviour
« Reply #13 on: May 07, 2018, 07:51:19 AM »
I heard people saying this that is why I looked for one that would work and also changed all settings accordingly in the BIOS.
Also stepper and everything else works just fine.
I wonder how the Auto-Calibrate should work since there is no feedback of the actual RPM or anything and also no feedback line from the VFD

The easiest thing to do is use one of the Huanyang plugins, and you'll get perfect speed control.

http://royaumedeole.fr/informatique/plugin-mach3-pour-vfdhuanyang/mach3-plugin-for-huanyang-vfd/
Gerry

2010 Screenset
http://www.thecncwoodworker.com/2010.html

JointCAM Dovetail and Box Joint software
http://www.g-forcecnc.com/jointcam.html

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: MACH3 spindle behaviour
« Reply #14 on: May 07, 2018, 12:17:18 PM »

Back in the old days before CNC that old Bridgeport had a number of  ratios, you selected the speed closest to what you required and got to work. Are you trying to tell me that all those jobs I did with manual mills and
lathes were compromised because I did not have the exact speed ratio available? Of course not, provided the surface speed is within 20% of the recommended for that material you can always find a feed that worked well.

Craig

Back in the day, the BP only went to 4200rpm max and the brain controlling the handles was very adept at altering rates depending on how the tool sounded and th colour of the chips, BUT it was never running a tiny cutter at 24,000rpm - there is no sound apart from the 'ping' when it snaps ;)  I'm not having a dig or anything, far from it but I would never state that speeds do not matter ;)

Offline TPS

*
  •  2,501 2,501
    • View Profile
Re: MACH3 spindle behaviour
« Reply #15 on: May 07, 2018, 02:26:27 PM »

Back in the old days before CNC that old Bridgeport had a number of  ratios, you selected the speed closest to what you required and got to work. Are you trying to tell me that all those jobs I did with manual mills and
lathes were compromised because I did not have the exact speed ratio available? Of course not, provided the surface speed is within 20% of the recommended for that material you can always find a feed that worked well.

Craig

Back in the day, the BP only went to 4200rpm max and the brain controlling the handles was very adept at altering rates depending on how the tool sounded and th colour of the chips, BUT it was never running a tiny cutter at 24,000rpm - there is no sound apart from the 'ping' when it snaps ;)  I'm not having a dig or anything, far from it but I would never state that speeds do not matter ;)

sorry guys thats an never ending Basic discusion, and i am realy sorry to say that, what has nothing to do with the Basic thread.

sorry again Thomas.
anything is possible, just try to do it.
if you find some mistakes, in my bad bavarian english,they are yours.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: MACH3 spindle behaviour
« Reply #16 on: May 07, 2018, 02:47:12 PM »

sorry guys thats an never ending Basic discusion, and i am realy sorry to say that, what has nothing to do with the Basic thread.

sorry again Thomas.

My fault, apologies ;)
Re: MACH3 spindle behaviour
« Reply #17 on: May 10, 2018, 01:33:31 PM »
hej everyone,
just wanted to let you know that the tip of @ger21 solved the issue.
Just bought a cheap RS485 USB interface und nov contriving the Spindle with RS485 and the huanyang vfd plugin.
Works like a charm.
Thanks

Offline TPS

*
  •  2,501 2,501
    • View Profile
Re: MACH3 spindle behaviour
« Reply #18 on: May 10, 2018, 02:26:47 PM »
hapy to hear, that you get it solved :D
anything is possible, just try to do it.
if you find some mistakes, in my bad bavarian english,they are yours.