Setting a lathe up for the first time.

[ecs]

Hi guys,

I've finally up to the part where I get to use my lathe. I've never use a CNC machine before so it's a little confusing. I've tried a few settings but with no luck. Everytime I use the wizard it just sets off the X hard limit warning.

I have installed homing sensors at the ends of each axis. Is this what I call zero?

I'm still yet to test the spindle because I keep setting off the hard limit. Is there a way to test the spindle without loading a gcode file?

I did manage to do a OD turn the other day but it was turning towards the tail stock not the head stock. Why and how do I fix this?

Is there a masso guide to run through once a new machine has been finished?

Cheers,

Josh

 

[machinedude]

you can use the MDI to turn the spindle on if the spindle motor is under Masso control. i'm not sure what the format for the G code is with this controller since I have hardly played around with it. but you will need a S500 M03 should turn your spindle on in a clockwise direction at 500 rpm. S always comes before your speed value and the M03 or M-code tells the machine which way to rotate the spindle a M04 would turn it in a counter clockwise direction and a M05 would stop the Spindle.



MDI is short for Manual Data Input. gives you a way to run the machine with out having a program. if you have a MPG( Manual pulse generator ) you can use the hand wheel to move you axis by hand to touch of your part to set your Z zero and switch over to your X to take a cut off your diameter so you can set that value after you measure it. just make sure your resolution is set to the smallest setting so you don't move to fast into your part.

 

[ecs]

@machinedude Thanks for that bud! Got in going

 

[machinedude]

@ecs

let me see if I can explain the basics for you here.

1. when you place your homing sensors that is what is referred to as you machine home position. This is basically a fixed position that that machine needs for reference so it knows where it is at. this is why you need to home the machine every time you start the machine up.
   
2. limit switches are a safety feature to prevent a hard crash and damage caused as a result. so the machine hit's a limit switch and alarms out with an over travel alarm before you get into real trouble.
   
3. soft limits are defined in the controller and are an extra layer of protection before you hit a hard limit.
   
4. when you think of your part zero's this would be what is referred as your program origin. with lathe work you would touch off the Z axis and set a zero once the face is cleaned up. Your passes for facing would take into account extra stock for your facing operation. you would start with a positive value and end up at Zero on this operation, when you set you X axis you take a small cut off the stock to clean up you diameter and measure it be for you move off that cut in the X axis.
   
5. Cartesian coordinate system is how determine your positive and negative values in your programs. this will depend on the style of lathe but in your case I think you have a tool post at the front so this image should explain things well.
   

 

[machinedude]

some other stuff to consider is which mode your in for your programs. lathes typically have two modes

1 radius mode

2 diameter mode

I'm am not sure if Masso gives you the choice between the two or not?

And depending on which side you doing your cutting will determine which way your spindle is rotating. on a front mount tool post you will be working in a spindle counter clockwise direction probably 99.9 % of the time if not 100%.

hope all this helps you out.

 

[ecs]

Thanks @machinedude all this info was very helpful sorry i took so long to reply!!

About the direction. I do have a front mounted tool post. Currently when a do a M03 it spins the correct way towards the cutter. This would mean i have it backwards correct?

 

[machinedude]

Quote from ECS on July 12, 2019, 6:19 am

Thanks @machinedude all this info was very helpful sorry i took so long to reply!!

About the direction. I do have a front mounted tool post. Currently when a do a M03 it spins the correct way towards the cutter. This would mean i have it backwards correct?

looking at the M code in the documents yes you would be correct. a M04 should actually be needed for a counter clockwise spindle rotation in your case. I would say you might have some wires crossed on the direction pins.

 

[ecs]

@machinedude its a 3 phase motor couldn't i just swap 2 wires and run the motor the other way?

 

[machinedude]

Quote from ECS on July 12, 2019, 6:36 am

@machinedude its a 3 phase motor couldn't i just swap 2 wires and run the motor the other way?

yeah I think you can change direction on the motor too. i'm not an expert on that end but I think it's possible.

 

[breezy]

Quote from machinedude on July 12, 2019, 6:31 am

Quote from ECS on July 12, 2019, 6:19 am

Thanks @machinedude all this info was very helpful sorry i took so long to reply!!

About the direction. I do have a front mounted tool post. Currently when a do a M03 it spins the correct way towards the cutter. This would mean i have it backwards correct?

looking at the M code in the documents yes you would be correct. a M04 should actually be needed for a counter clockwise spindle rotation in your case. I would say you might have some wires crossed on the direction pins.

Quote from ECS on July 12, 2019, 6:36 am

@machinedude its a 3 phase motor couldn't i just swap 2 wires and run the motor the other way?

Swapping two wires on the motor is the correct way to fix the spin of the spindle, if pin7/6 is connected to REV and pin5/4 is connected to FWD. Otherwise correcting the direction wiring is the correct fix.

Having the spindle turning the wrong way will lead to problems down the track when you forget that things are backwards.

Regards,

Arie.

 

[ecs]

Thanks @breezy

I have checked and i have everything wire correctly according to the wiring diagram. So i will swap the motor wires to have it run the correct way.

Another problem i have noticed is i wrote a little program with the wizard but the machine turns away from the chuck not towards it. is this something i did wrong in the wizard?

Thanks,
Josh

 

[masso-support]

@ecs the direction of the tool moving will depend on the tool in use and its direction, please goto the F4 screen and edit the tool you are using, make sure the tool position rear or front is selected as required because this will change the direction of your X axis movement when machining.

 

[ecs]

Thanks @masso-support

I'm having trouble doing the calculations for my calibration.

I have a 5mm pitch ball screw and i have a 2:1 pulley system (60 teeth on the screw and 30 teeth on the motor).

Motor - 5 / 2 = 2.5mm ?
Drive - 2500 (2500P/R incremental encoder(standard), 17-bit absolute encoder)

But its way out at these figures. Both axis have the same pitch screws and pulleys and motors. And both having the same trouble.

Thanks,
Josh

 

[evermech]

@ecs it looks to me like you are getting 2 motor revolutions equal 5 mm travel.

2 motor revolutions also equal 5000 pulses so it's 1000 pulses per mm of travel if I'm not mistaken.

Guy

 

[masso-support]

Hi Josh

Had a bit of time so I wrote a spreadsheet to calculate the values to enter into Masso for calibration. I ahve attached it below. You just need to select the one of the 4 pages and fill in the values shown in Red. The values you enter into Masso are shown in Blue. I think you will want Leadscrew Metric for your setup.

Once you have got it moving you can run the calibration wizard to fine tune the values.

Hope this helps

Cheers

Peter

 

[ecs]

@masso-support Thanks Peter.

The part where is says micro stepping do i use the value "1" for a servo drive?
When i use the value "1" i get 5 - motor and 5000 - drive. But this is horrible. The machine moves about 50mm when the readout moves 350mm

I've just double checked my ball screws and they are 5mm (checked with a dial indicator) and the pulleys are a 60 tooth and a 30 tooth and the 30 tooth is on the motor.

Am i putting the details in wrong?

 

[breezy]

Quote from ECS on July 17, 2019, 12:19 am

I've just double checked my ball screws and they are 5mm (checked with a dial indicator) and the pulleys are a 60 tooth and a 30 tooth and the 30 tooth is on the motor.

Am i putting the details in wrong?

@ecs

Motor: Distance / Rev should be 2.5mm. With your gearing the motor turns twice for each rev of the ball screw.

Drive: Pulses / Rev is set to the number of pulses it takes to make the motor to complete one Rev.

Regards,

Arie.

 

[evermech]

Hi @ecs

you should have the actual pulses per rev of the motor in that field so that would be 2500. Because you have a 2/1 reduction via your pulley system 1 rev of the motor will turn your screw 1/2 turn

because you have a 5mm per rev screw 1/2 turn is 2.5 mm so in the distance per rev field it should be 2.5 mm

feedrates and other adjustments can be altered to keep the amount of pulses you need under the 110,000 that the Masso can supply. I try to shoot for about 75% so around 80,000 pps/ps

in the event that you can't get a high enough rapid speed without going over the available pulses the Masso can give there are some settings in your servo drivers to change but that's secondary to getting the calibration done accurately first

Guy

 

[ecs]

@evermech @breezy Thanks for that guys.

This is how i had it originally setup. I moved the machine 100mm on the readout and get only 18mm of actual travel.

I've double checked the drives in the software and they are showing 2500 pp/r

I have to set the motor to 0.31500 to get the machine to be close to accurate. That was just me playing with it to find those numbers. But it doesn't make any sense nor give me confidence it will be accurate.

I'm going to try update the software and see if that does anything. I'm on v3.39

 

[evermech]

Are you running servo drives? They usually have a setting called electronic gearing. Is it possible that those parameters are correct? Did you get them used?

just a long shot but nothing else is making sense

Guy