4 axis Milling with Rhinocam V2

[prdp141]

Hi Guys,
I have been visiting this forum for quite some time now (it's brilliant) and have finally plucked up the nerve (...well had to) to ask a 'probably lame' question in the hope that someone can throw me a lifeline.

I have modeled this item (pic #1) in Rhino V4 and setup the MOP in Rhinocam V2. My problem is can't figure out how to get full (true) 4 axis machining on the piece. My cnc machines the item out using z, x and a axes only but not y. In other words the item is machined on a rotational, incremental basis turning on the x axis as in (pic #2) while the tool transverses along the centre-line (z axis). Unfortunately the result is I have 'dead zones' that can't be accesses by the tool.

I found an article where a guy (a lot smarter than I am ) is using Visualmill to make RC model aircraft undercarriages (pic #3) and uses the sort of toolpaths that I would like to achieve. Assuming that Rhinocam 2 is pretty much the same as the stand-alone Visualmill, I'm thinking that I seem to be missing something in my MOP setup, which can be seen in pic #2.

So...has anyone got the answer I seek?


Thanks
Phil

[michaelthomas]

The only idea that comes to mind for me is to use a 2.5d path to finish those areas up. I don't have a a rotary fourth......so there may be a better way to do it. I know you can combine 2.5, 3, and 4th strategies, though.

[tjd10684]

ya this looks like a multi strategy part to me. what i would do is rough it out (possiblly using roughing mills cant tell if you can because their is nothing to get a sense of scale) using 2.5 and 3 techniques to get it close then do the 4th with the biggest ball end mill you can get away with (better surface finish that way) and then come back in again with a small flat mill to get the hex shapes in there again using 2.5 techniques

[prdp141]

Thanks guys for your input. I think you're both right on the money. That strategy had gone through my mind (very quickly) but looking for a fast fix avoiding extra work I was hoping in a way that I'd missed something in the MOP options.

Damn! Back to the drawing board. It hurts to think sometimes

Cheers
Phil