Recommendations for component patterning and spacing (avoid machining other components)

[jw.hendy]

I'm using component pattern for the first time and trying to densely nest parts as close as I can. Is there a recommended strategy for knowing in advance how close I can space them? Because this patterns operations blind to the other instances, I found myself a little confused on how to make sure I don't machine other components.

My current thinking is to ensure that all my operations use silhouette with "tool on center on boundary" for containment. My biggest tool will be a 1/4 bit, and my spacing is 4.5mm, so I know I'm a tool radius away. I like the component pattern, as computing operations for 18 parts is brutal vs. just one + patterning. That said, if I pattern the bodies and run them as one setup, the operations are aware of all the other bodies. If I have a setup with just one component and pattern the operations, I am not seeing a way to say something like "don't machine into the other components present," and thus it seems left to me to make sure my tool paths don't encroach on neighboring parts.

Am I understanding how this works correctly? Namely, apply paths to all bodies and pay the computing prices, or leverage patterning, but it's on the user to make sure toolpath footprints don't actually spill into the neighboring components?

Many thanks.

[mattdlr89]

I used this for the first time recently and had the same problem. I ended up patterning the model and stock so I could check there were no clashes in the simulation.

The other way I thought was to sketch a boundary that can be used to contain the toolpath that could use all the available space between components. 

I'm commenting here to see what other users who use this feature regularly do so hopefully they will have some better suggestions for you. 

[jw.hendy]

Cool! (Both with the idea and I admit I find it refreshing when I get a nice sanity check and understand it's not just me).

These are chess pieces and here's an example. I copied one and flipped, then will be patterning them into a grid for the boards I have on hand (number depends on width of the board).

I think silhouhette or bounding box should do it, but it gets a little hairy as technically I can go outside it by 1/2*tool_width because I know I have some room. It would be awesome if there were a way to have the setup only contain one piece, but some other option like "don't machine into other stuff."

In pursuit of optimizing tool paths (not machining more wood than I have to), I've used project to recreate the silhouette, then done an offset of that projection to make my machining boundary. That could apply to what you're proposing and give me a good boundary to use. Then I'm always "inside boundary" vs. worrying about tool-on-center + some offset based on the current width.

Thanks for chiming in.

[daniel_lyall]

Definitely do a model of the stock, having a sold model of the stock makes it easier as you can have it see-through and make sure on all sides the part is inside the stock by eye. Do it from a sketch then you can position the sketch in a position where it is correct for the first part ever using a constraint of a joint a joint is better, then when you do the pattern you know it is tool + part in the y or x and or x and y if doing the pattern in two directions, it makes it simple to do if you plan ahead.

[jw.hendy]

Actually, maybe this is a good point to clarify... my stock is actually shared between pieces. I want to nest/pack them as close as possible in order to maximize material. Or, put another way, I am packing multiple parts into a single piece of stock, but I want to use the CAM pattern, otherwise I have to pay the atrocious penalty of clicking massive numbers of items.

For example, if I pattern bodies and have, say, surfaces to avoid, instead of clicking 2 surfaces on one component, and that choice is essentially patterned for me, I now have 36 surfaces to click on my 18-up layout. And again, the computation time is way longer.

Hopefully this better clarifies. That said, I could still use the sort of "offset silhouette" technique as an organic stock boundary that ensures I'm not into the neighboring part. Is that in line with a route you might suggest? Many thanks.