Spin High/Med/Low

All things related to the Centroid Acorn CNC Controller

Moderator: cnckeith

Philtrueman
Posts: 80
Joined: Mon Jan 03, 2022 11:52 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: United Kingdom, St Helens
Contact:

Spin High/Med/Low

Post by Philtrueman »

Can someone tell me, what is the function of these buttons on the Acorn VCP?
I have a 4 speed belt drive pulley reduction for the spindle speed. Can i program different spindle speeds to suit the different spindle gearing ratios?
The only other option is to fit a larger spindle DC motor so that i can have only one drive belt on my Boxford 250PC lathe.
tblough
Posts: 3072
Joined: Tue Mar 22, 2016 10:03 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: Yes
CNC Control System Serial Number: 100505
100327
102696
103432
7804732B977B-0624192192
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Boston, MA
Contact:

Re: Spin High/Med/Low

Post by tblough »

CNC12 has provision for up to four spindle gear ratios. This allows for high/low gearing like on a Bridgeport knee mill, or a lathe with a gear-head spindle. Centroid will apply the appropriate gear ratio and display/command/use the correct spindle speed.

The issue is how to tell CNC12 what gear you are using. One way it to add microswitches to the transmission on the device and connect these to unused inputs, and then customize the PC to react to those inputs.

Another way is to use manual switches or buttons (like the VCP) to manually tell CNC12 when you have changed gears. This is the cheap and easy way, and for some, all that they need.

Look at parameters 65-67 in the mill or lathe operator's manual.
Cheers,

Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
Philtrueman
Posts: 80
Joined: Mon Jan 03, 2022 11:52 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: United Kingdom, St Helens
Contact:

Re: Spin High/Med/Low

Post by Philtrueman »

I have had a look at parameters 65,66,67 Do i enter the drive reduction ratio in these fields? My lathe has 4 belt drive reduction speed ratios. How do i enter another 4th speed ratio to make it 4 speeds? I also tried to enter the gear ratios in the low and medium boxes but it will not allow any numbers other than 1 or 0.
Attachments
report_0CB2B7D44535-0716192281_2022-01-14_16-00-06.zip
(592.55 KiB) Downloaded 47 times
cncsnw
Posts: 3764
Joined: Wed Mar 24, 2010 5:48 pm

Re: Spin High/Med/Low

Post by cncsnw »

The highest range uses the maximum speed you set on the Control Configuration screen (or on whatever Wizard page provides the value for the Control Configuration screen). There is no gear-ratio parameter for the highest range.

Parameters 65, 66 and 67 are the speed fractions for lower gear ranges. These lower ranges are generally called low; medium-low or mid-low; and medium-high or mid-high.

For example, if in your lowest gear the spindle runs at 1/8 of the speed it would be running in high gear (for the same motor speed), then you would set Parameter 65 = 0.125.

Note that actual motor RPM is generally not relevant. If even your highest gear has some speed reduction (or increase) between the motor and the spindle, it is the spindle speed (not the motor speed) that you put on the Control Configuration screen. Parameters 65, 66 and 67 are fractions of the high-range spindle speed, not of the motor speed.
cnckeith
Posts: 7166
Joined: Wed Mar 03, 2010 4:23 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: Yes
CNC Control System Serial Number: none
DC3IOB: Yes
CNC11: Yes
CPU10 or CPU7: Yes
Contact:

Re: Spin High/Med/Low

Post by cnckeith »

fyi.. for anyone else reading this thread the wizard spindle setup menu supports up to three ranges,
and you can use the CNC12 parameters if you have more than three ranges.
spindle range.PNG
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
Philtrueman
Posts: 80
Joined: Mon Jan 03, 2022 11:52 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: United Kingdom, St Helens
Contact:

Re: Spin High/Med/Low

Post by Philtrueman »

cncsnw wrote: Fri Jan 14, 2022 12:48 pm The highest range uses the maximum speed you set on the Control Configuration screen (or on whatever Wizard page provides the value for the Control Configuration screen). There is no gear-ratio parameter for the highest range.

Parameters 65, 66 and 67 are the speed fractions for lower gear ranges. These lower ranges are generally called low; medium-low or mid-low; and medium-high or mid-high.

For example, if in your lowest gear the spindle runs at 1/8 of the speed it would be running in high gear (for the same motor speed), then you would set Parameter 65 = 0.125.

Note that actual motor RPM is generally not relevant. If even your highest gear has some speed reduction (or increase) between the motor and the spindle, it is the spindle speed (not the motor speed) that you put on the Control Configuration screen. Parameters 65, 66 and 67 are fractions of the high-range spindle speed, not of the motor speed.
Thank you for explaining the settings. I understand how it works now.
Philtrueman
Posts: 80
Joined: Mon Jan 03, 2022 11:52 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: United Kingdom, St Helens
Contact:

Re: Spin High/Med/med-Low/Low

Post by Philtrueman »

I have changed the parameters in number 65 Low 66 medium/low and 67 medium/High to what the gear ratios are on my "4 speed " lathe but in the utility wizard it still only shows Low and medium it is missing the medium low box. The medium/high box is missing. Is it possible to change this in the software?
Attachments
Speed ratio.jpg
tblough
Posts: 3072
Joined: Tue Mar 22, 2016 10:03 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: Yes
CNC Control System Serial Number: 100505
100327
102696
103432
7804732B977B-0624192192
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Boston, MA
Contact:

Re: Spin High/Med/Low

Post by tblough »

The answer is 3 post above.
Cheers,

Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
Muzzer
Posts: 728
Joined: Mon Feb 19, 2018 2:52 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: 38D269594F9C-0110180512
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: UK
Contact:

Re: Spin High/Med/Low

Post by Muzzer »

One thing I found confusing was how to configure the ratios if you have only 2 speeds - where do you define the low ratio? The high is the "straight through" 1:1 ratio ie fairly obvious but for the reduction ratio, do you specify the lowest ("low") or the second highest ("medium") for that purpose? If you choose the "low" ratio, does it matter how you configure the intermediate ratios? I forget how I set mine up in the end but I do recall that it involved some experimentation.

On my machine I have pneumatic solenoids to move between the 2 ratios, as well as microswitches to tell me if the gears have fully meshed (based on the actual position of the solenoids). That avoids grinding the gears if the gears have not fully meshed. The M3 and M4 macros check which ratio is required for the demanded spindle speed and don't exit until the correct ratio has been selected and fully meshed. I briefly pulse the VFD before doing a retry, if meshing wasn't achieved at the first asking. Obviously if you change the spindle speed subsequently without issuing another M3 or M4, the ratio will remain unchanged.
tblough
Posts: 3072
Joined: Tue Mar 22, 2016 10:03 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: Yes
CNC Control System Serial Number: 100505
100327
102696
103432
7804732B977B-0624192192
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Boston, MA
Contact:

Re: Spin High/Med/Low

Post by tblough »

Doesn't really matter since it's up to you to configure the inputs to tell CNC12 what range you are in. If you have two ratios, low can be any of the three. Just be sure to use the same range when defining the input.
Cheers,

Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
Post Reply