Homing Really Necessary?

[Beamer]

I may be way off base and if so, i'm sorry - but it sounds like your experience is clouding your judgement. Stepover is ignored for profile toolpaths - pretend its' not there - it won't affect a thing in profile toolpaths.

Now - I'm gonna ask a question that might seem blunt, but it sounds like some assumptions are being made so I'm going to boil ti down to slow and simple questions:

Have you actually generated any gcode and SEEN this stepover causing you problems or are you just annoyed that the field has to have a value? If the former, then there's a problem. If the latter, the problem is only in your mind.

[JPX2000]

For the toolpaths where a stepover is needed the value is used, for toolpaths where it's not needed it's not used so it's logically zero anyway.

Yeah, Adrian, that's what I was thinking. But it's showing up in the simulation, so I don't know. I guess I could go into the G-code and edit it out, but that's a pain in the ass.

It won't cause any problems with other toolpaths. It's not how it works. If you could set it up the way you wanted to you would need to create a different tool definition for toolpaths that needed a stepover and those that didn't. That would be far more likely to cause confusion.

The whole idea of these types of programs is so that you don't need to worry about the minute details. Many of us can program complex toolpaths by hand without problems but that's not the market Cut2D is aimed at.

I'm probably overthinking this. I have been CNC machining for 30 years and really wanted a simple program to handle simple profiles and contours. The people at Vectric will hopefully get back with me soon.

Thanks.

[rscrawford]

As far as homing goes, it is extremely useful if you use jigs. You are able to index the jig to the table (with dowels, or any other method) and be able to return to that exact spot every time you start up your machine.

If you are simply placing a piece on the table and resetting X0Y0Z0 every time, then it is not as necessary (but still nice to have to make sure you don't wreck your machine by ramming into the frame!).

[Adrian]

Could you post a picture of the stepover showing in the simulation on a profile toolpath? I've been using the software since 2005 and I've never seen or heard of that happening.

You made a comment earlier that your Cut2D allowed you to do offsets on the profile toolpaths. That option is only available on VCarve/Aspire so I think you're getting that function mixed up with something else.

[JPX2000]

I may be way off base and if so, i'm sorry - but it sounds like your experience is clouding your judgement. Stepover is ignored for profile toolpaths - pretend its' not there - it won't affect a thing in profile toolpaths.

Now - I'm gonna ask a question that might seem blunt, but it sounds like some assumptions are being made so I'm going to boil ti down to slow and simple questions:

Have you actually generated any gcode and SEEN this stepover causing you problems or are you just annoyed that the field has to have a value? If the former, then there's a problem. If the latter, the problem is only in your mind.

Hey, Beamer, I'm an old fart, so I like blunt. It's an annoyance. Adam Moran from Vectric confirmed that the stepover operation was ignored in a profile operation. Guess somebody should have included that in the documentation. G codes (almost all that I've generated for a 1" test square) are not showing these stepover passes. I should have taken the time to examine them.

So, case closed. I'm now trying to figure out how best to home my little unit, given that there are no limit switches installed yet. It really gets confusing on here when it tells you that machine 'home' can be reset by setting your part zero. We'll see.

Muchas gracias for the time and attention. Gonna go plug this thing in and go play.

[JPX2000]

Could you post a picture of the stepover showing in the simulation on a profile toolpath? I've been using the software since 2005 and I've never seen or heard of that happening.

You made a comment earlier that your Cut2D allowed you to do offsets on the profile toolpaths. That option is only available on VCarve/Aspire so I think you're getting that function mixed up with something else.

Hi, Adrian... mystery solved, case closed. Profile ignores stepover (but it's still there buggin' me - should have been documented in the manual). Not sure anymore if the sim was showing the stepover. Would really like to find out how to slow that down in the Cut2d animation.

G codes are confirming a single pass around the profile per pass depth. This is my failure to trust my experience. Also, Adam Moran from Vectric answered my e-mail and sure enough, profiles ignore stepover. Cool.

Probably need to work on homing this machine and getting used to setting up part zero points. Thanks for looking at my ramblings.

Cheers.

[JPX2000]

As far as homing goes, it is extremely useful if you use jigs. You are able to index the jig to the table (with dowels, or any other method) and be able to return to that exact spot every time you start up your machine.

If you are simply placing a piece on the table and resetting X0Y0Z0 every time, then it is not as necessary (but still nice to have to make sure you don't wreck your machine by ramming into the frame!).

Thanks, Russ. This is beginning to feel like another day in the shop. I think I can run the table to the limits (no switches, just stalled stepper motors), back off maybe a quarter inch or so, hit zero, and go to another corner, or edge, or whatever. I saw a P1 and P2 reference in the manual, so the homing part vs. 0,0,0 for the part setup might not be a problem.

[rscrawford]

I could not live without my exact machine home. I would install at least 3 limit switches and set up a constant machine home. On my machine, as soon as I turn it on it has to 'home' itself, by touching off each limit switch, then it moves to 'machine home', which is 0,0,0. This also lets it know the exact height of the spoil board (saved as an offset with respect to the Z-axis limit switch), and my ATC tools are all set to that zero..

So for me to cut a sheet of plywood, I simply turn the machine on, home it, set my plywood on and start cutting. No messing around with setting zeros, measuring bits, etc. And its the same EVERY time.

[Rcnewcomb]

Russ,

On my machine, as soon as I turn it on it has to 'home' itself, by touching off each limit switch, then it moves to 'machine home', which is 0,0,0. This also lets it know the exact height of the spoil board (saved as an offset with respect to the Z-axis limit switch), and my ATC tools are all set to that zero.

I really love that feature of the CAMaster machines.

[Adrian]

A homing switch on the Z is a massive time saver. I added one to my ShopBot a couple of years ago and the ability to automatically home all three axes as part of the warmup routine is so much nicer than messing about with zero plates etc.

[scottp55]

Adrian, Did you have to write a new C3 Routine? (X,Y zeroing of prox/limit switches)

[Adrian]

I kept the C3 the same and wrote a new routine for the Z that I can call from other routines where needed. Rather than using offsets I auto zero to the machine bed with a fixed touch off plate and then use the Z limit to set the safe retract/Z movement range. That suits the way I work with 99% of the jobs requiring a Z zero at the bottom but once you've got a top Z switch there's all sort of things you can do with a bit of code.

[scottp55]

Thanks for explaining Adrian!