BobCad V23 Coordinates Backwards from the machine.
Hello Fellows, I have a new to me Hardinge CHNC II lathe and I am trying to figure out the programming using V23 lathe and I am running into some problems and hope you can help me figure out the best way to solve them.
Essentially every thing is backward on V23 to my machine. BobCad 23 is using right hand coordinates with Z+ away from the spindle face and X+ away from the operator, but the machine uses left hand coordinates which is the same for Z+ but X+ is towards the operator.
At first I thought it would be no problem I just changed the view so I was looking at the bottom instead of the top and that makes the actual drawing fairly easy, however when you go to pick your tool orientation and all of that every thing there is backwards too. The M3 & M4 for the spindle rotation is backwards as well.
So I am wondering if there is a way to reverse these things so that they match the machine. It has been suggested that maybe the X output needs to be reversed in the post processor not sure if that will correct the problem or not. I noticed in V25 it looks like you are able to switch the X+ and X-. Is that possible in V23?
I imagine that someone out there is using Bobcad for one of these machines and has already overcome these problems.
Thanks Gary Breiling
Re: BobCad V23 Coordinates Backwards from the machine.
Gary
No need to change the view, you should still be drawing in the upper left hand quadrant on your BobCAD screen.
You should then have the Z cutting towards the chuck and the numbers should be Z-, a 1 inch cut towards the chuck should show as Z-1.0 in your code.
If the toolpost is at the front of the machine and actually physically moves away from the operator to make a cut then that should also show as X- moves if you cut towards the middle of the workpiece so a 1 inch face cut from the outside of your bar should show as X-1.0 in your code.
What may be confusing you is that the BobCAD default setup is for a slant bed lathe so it looks to you to be wrong. however if you can visualise getting a slant bed toolpost and rotating it towards you around the spindle axis it would then be as per your lathes physical configuration.
Now, that should mean that for the slant bed lathe the movements would be X- towards the center of the bar and Z- towards the chuck, that from what I read in your post is what you are asking for correct ? ?
If so do nothing and select your tool orientations for turning and facing as 1 and 4 for boring, I am assuming that the lathe does run clockwise by default, by that I mean if you manually select forward it runs clockwise and if you select reverse it runs counter clockwise.
I assume you already know this but I`ll add it anyway, spindle direction is always as looked at from the back of the spindle, not looking at the chuck.
If your tooling is fitted to the toolpost with the cutting edge/tips facing upwards then if the tool is approaching the workpiece from the operator towards the workpiece then the spindle should be running in a clockwise direction using the M3 code.
Spindle direction is easily set in the feature, there are two buttons, CW and CCW, clockwise and counter clockwise.
If it is one of those oddball machines that have the spindle going in the opposite direction to "normal" the just select the opposite setting, if you want to change it in the Post Processor then it is usually the following lines that can be edited to get what you need :-
782. Spindle forward String ? "M03"
783. Spindle reverse String ? "M04"
You can easily open the PP in Notepad and swap the M03 and M04 and the code will be output with M04 as the spindle direction but I don`t think you need to do that :D
Hope these ramblings are of some help to you, all of the above assumes that you are using standard RH tooling, in other words it cuts from the right :D
Regards
Rob
:rainfro: :rainfro: :rainfro:
1 Attachment(s)
Re: BobCad V23 Coordinates Backwards from the machine.
Thanks and every thing you say makes sense. As for the drawing I guess I am just going to need to get used to viewing it upside down. When you draw the opposite of what you see in the machine all of the moves X and Z are correct it just seems much easier to make a mistake when you every thing is opposite of reality.
As for the spindle after seeing what you have written it is correct. I did not know that BobCad was viewing the rotation from the back of the spindle. My Hardinge manual says this " M03 Spindle Forward - causes the spindle to run in the forward direction at the programmed speed (S word). The spindle is running in the forward direction when rotating counter clockwise as viewed from the turret end of the machine."
So I was selecting counter clockwise in the BobCad options and getting a M04 for spindle direction and naturally I jumped to the conclusion that this was backwards also.
I still have one question about the tool orientation selection. Say I am facing .100" off the Z end of the work piece using a right hand tool. Which tool orientation number do I select. If I look at the machine with the cutting edge up it seems like I should pick #8 but if I consider every thing upside down like on a slant bed I guess #5 would be the correct option. I have attached a picture of my BobCad selection choices.
Attachment 277316
So I guess the question is everything else is upside down so are they showing me the top or bottom of the inserts here in this picture and does it even matter which one I pick.
Thanks for the help! Gary
Re: BobCad V23 Coordinates Backwards from the machine.
Hi Gary
Yes, the correct Facing orientation would be #5, if you look closely at the image you will see that the #5 option shows it going from +X towards -X which I am thinking is what you want.
For Turning then the correct orientation would be #1, it will be a little confusing at first till you get used to it but it`s a lot easier than trying to swap everything around :D :D
Regards
Rob
:rainfro: :rainfro: :rainfro:
