Different approach to set "Home"?

Hey Maslowians, I wonder if there might be a better way to set Home in GC? I have been working with small scraps and trying to place a part on them can be tough, especially when working close to the edges. It is time consuming to move the sled to the edge of the cut, measure how far off you are, move the sled back to home and offset, reset home, then move the sled back to double check. Then check the other axis. Takes a while, as you guys might know by now.

In my concept, we move the sled to our desired outside cut point on the stock, then drag the workspace in GC “under” the sled until we line up with our contours. Then click “set home” and through some magic that you guys do, it knows how far we moved the original “home” and sets accordingly.

I don’t know if it’s possible, maybe not. If not, I’ll move this to the “pipe dreams” thread.

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Have you thought about using an L shaped fixture (aka piece of scrap) screwed to the backer and spoil board near the center? Make it the same thickness as your material and wide enough for the sled to ride on. That will give you a known corner position plus support for what you’re cutting. Screw on a couple of clamp blocks for the other edges.

I’m thinking about drilling a grid and putting t-nuts in from the back for fixturing and clamping, maybe 6" centers, when I get to the final frame. Pretty common on other CNC devices. Quick job to drill the spoil board with a big bigger holes, too.

This is a better approach: using spoilboard to construct a jig to secure your workpiece, or as @dlang mentioned, using sacrificial fasteners on the work piece itself to hold in an appropriate position.

Moving ‘home’ would result in the machine being unaware of the actual machine edges/dimensions etc. its a bad idea thats more trouble than its worth. Its better that you have a precise location both on the work surface and in GC, if that is achieved you should be able to secure whatever you’d like wherever you’d like and have it still be accurate.

I don’t think you guys understand what I’m getting at. Say I have a file of a part that I want multiples of, and I want to cut them on different scrap sections. Maybe I want to place them as cuts all over a large piece of scrap. You don’t want to move the stock for every part. Trust me, once you start using your machine more, you’ll get what I mean. The first time your sled goes off the side of your stock, or into your other part.

I just drive my sled to a bare patch and ‘Define Home’. I try to keep my files small - few pieces per file, and to put the pieces all just northeast of the home position in the file.

Really? No one else has gotten frustrated driving the sled all over a job file to make sure it fits? I guess I’m doing it wrong.

There are enough ‘funnies’ to the way Kivy handles varying screen resolutions that I’d be surprised if ‘drag the sled’ could be made to work across the platforms. Now that I’ve said that, someone will surely accomplish it by breakfast time :smile:!

I think I get what you are saying. The click and drag behavior is a cool idea but I think it might be pretty difficult to implement so it might be a ways off.

What about a “mark point” feature so you could move the sled to the edge of an available space and click “mark” and it would leave a mark screen so it’s easy to check if the part is going run into the cut part?

Thanks Bar. My workflow must be strange, but it does suck to try to extrapolate where to put “home” by driving to a location, checking offset, then driving back to center and trying to match it. Your “mark point” would work well. Then when Home is set, the file will shift under the point and one should be able to tell where the cut perimeters are. I’m not cutting anything for a week or so, since I dropped my usb connection I have to recal, so I might as well get that new board you sent out hooked up and do some upgrades to my frame and sled. But, if you can implement something like that in time, I’d sure appreciate it.

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I’m on it!

Would you be willing to make a GitHub issue for it so I won’t forget?

As soon as I’m done with this darn CNC tiny house on Sunday I’m going to focus all my attention on shrinking our issues list on GitHub full time

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