need help for my cnc lathe project

[neo_237]

I have a cnc lathe Masso controller using it for cnc lathe conversion

serial G3-5764 , software V3.46

Im new to Masso and also to cnc lathe, so I,ve some questions about both (mostly could be newbie questions so bear with me please)

1- to calibrate my steps per unit for each axis (x & z) I used a 1-inch depth indicator but as far as I know it error should be measured along the whole axis travel, so what is the best way to measure error with .001 accuracy or more?

2- why can't I find a "start from line" button in Masso lathe software?

3- how to override feed and spindle speed in Masso cnc lathe software?

4- what's step and continuous modes in Masso cnc lathe software?

5- how to review g-code lines in Masso cnc lathe software?

6- I don't have a presetter in my converted cnc lathe, so what is the best way to get tool zero in x & z axes accurately?

sorry for the long list of questions but Im about to finish my project and any help answering these questions is greatly appreciated

 

[breezy]

@neo_237,

I'm not a lathe user but will try to answer some of your questions.

1- to calibrate my steps per unit for each axis (x & z) I used a 1-inch depth indicator but as far as I know it error should be measured along the whole axis travel, so what is the best way to measure error with .001 accuracy or more?

If you can adjust your axes travel to 0.001 in an inch you are achieving 0.1% error, now if you extend that over say 30 inches of your X axis then if you are within 0.03 of an inch in that distance you are still achieving the same 0.1% error, now assuming you can get within 0.005 of an inch in that distance then your error is 0.017%. So if you can find someway of attaching a long scale to your lathe and adjust your calibration within 1/32 of an inch or better then you have achieved the 0.001 accuracy that you are after.

2- why can't I find a "start from line" button in Masso lathe software?

I think this was explained in another post but it isn't available in the lathe version.

4- what's step and continuous modes in Masso cnc lathe software?

In step mode, each time you operate any of the jog buttons / keyboard shortcuts MASSO will move the axis one "step" of the size determined by the scaling factor, whereas in continuous mode MASSO moves the axis continuously whilst the button / key is held "pressed".

In regards to your other questions I will leave them to members who are lathe users, as my answers more than likely would be incorrect.

Hope this has helped you to understand.

Regards,

Arie.

 

[madscientist]

My advice for setting tools on a lathe is to have a tool set that is standard, generally an audio/visual probe as they are cheap and easy to use. Leave this tool set in a holder and never remove it ( if you have the luxury of a quick change tool post) this will be your master and act in the same manner that a touch setting arm would. Set your other tools in holders and leave them set also. This allows you to have a list of tool offsets thatvyoubcan then save in the software. Depending on the nose radius of individual inserts you will then only have to make small adjustments in the offset compensation rather than the actual offsets them selves. When setting a job you use the master to touch on in X and Z and then as you call your tools and offsets you can have some certainty that you should be within 0.2mm or so. The important things to remember are that your tool post has a location pin so that it s positions are consistent when rotating, DO NOT MAKE CHANGES TO OFFSETS unless you are setting a new tool. Make sure the + or - values on the offsets are the right way around also otherwise you will crash. This method is costly as it means if you are running 8 tools then you will need 8 quick change holders. What it does do is gives you speed in setting the machine and gives you security of avoiding a crash for when your having an off day or in a rush and forget to touch a tool off.

as for calibrating your stepper motors I would see if the Masso is capable of handling this for you. Generally you turn some bar stock to a known size on diameter by Measuring with a mic and without moving the x axis from where you took the cut, check the parameters and adjust so that the controller is giving a true indication of the size that you have measured.

alternatuvely you can set up your touch probe in a fixed position and calculate a known position from your machine home position(these numbers will make very little sense when looking at them but the controller does the calculations) using this method will require touching each tool off on the touch setter each time you mount them for the first time. You can then use any tool to touch off of Z by touching the tool against the piece and then using MDI to call the tool offset( this will set all tools to the Z datum provided you have entered the tool offsets in the controller. X axis is always taken off axial axis of the chuck so should not require setting off each work piece.

once you have used either method to set your tools, you can achieve production by setting a feed out cycle. I have a small brass puck mounted on the tool post out of the way but permanently attached(give this an offset and call it say tool 32) you can program calling tool offset 32 and then program it to go to Z +0.2mm and X +10mm with the chuck open and not rotating to prevent a crash. You can then feed the bar stock out till it touches the brass puck and lock the chuck. Move the tool post away and viola you will consistently have 0.2mm of green to fave off in Z each time and you don t need to keep setting work offsets.

sprry this is long winded but I hope it helps.