Machining Margins
I got the basics of the machining margin code working. Below you can see the roughing limited to .25″ around the standard MeshCAM model. This should make 2-side machining, and machining using supports, much more attractive. No longer do you have to define the border size either, the supports run to the edge and you just define how far beyond the model to machine.
I still need to figure out where to put the setting for how far to machine. I think I’ll probably put it in the global parameters section of the toolpath dialog since your selection will likely be based on your tool diameter selection.
Finishing is still generating too many retracts when the path is linked so I still have that to take care of before a release.
Comments
5 Responses to “Machining Margins”
Sweet.
Very nice.
I do see one problem (or feature request). I often need very tight control of multiple support sizes and their placements… so I add them to the model. With your new set up MeshCam recognises the model and doesn’t consider the supports when using the roughing margin. With my work flow the tabs would also have the margin applied, and they wouldn’t be tabs anymore
One solution would be an option to open the model (without tabs) and then Import just the custom tabs as a separate .stl.
Jeff
Jeff, how are you doing it now? When I am doing a part with modeled supports, I also model the rawstock around it and specify “don’t mill top of stock” and it has worked fine. In that case, I make a “top” stl and “bottom” stl and just use two sessions of single-side machining.
For two-sided machining, I am happy with Robert’s current support generation dialog. If needed, each support can be individually defined in terms of height and width. The main limitation (if there can be one) is that the supports are perpendicular to the nearest frame wall, and in some cases it would be nice for the supports to be radial from the part centroid. It would also be nice to have a “slider” to adjust the support’s vertical position rather than the top-middle-bottom.
I’d more than settle for an intermediate solution where the supports dialog is as it stands, but Robert offset the part’s projected outline for the inside of the frame, rather than the rectangular opening it has now.
Best regards,
Randy
Randy,
Sounds like just about what I do, model the part, supports, and border. I don’t use “don’t mill top of stock”, instead I set the stock “geometry offset” to a slightly negative value so that it doesn’t cut the stock perimeter walls. Your technique should mill a little faster but on ‘long’ constant Z cuts my mill is quite fast, it’s the really short cuts with Z bouncing up and down where it never accelerates even close to max feed which are painfully slow on highly textured or curved surfaces.
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PS: Thanks for the comment about individually defining each support, it inspired a little non intuitive playing but I figured it out (note to Robert for the manual).
Point taken about the manual. Now that the supports and two-side machining are becoming more of a first-class feature I think I’ll have to add much more documentation and probably a few videos.