3D HighSpeed Hybrid

[Lord Wukits]

I'm having issues trying to get the Hybrid toolpath to start machining a mold from the top, working it's way to the bottom.[2017 mastercam for solidworks]

With the "preserve Z passes" disabled, the tool path is quite efficient and does exactly what I would like. BUT it starts from the bottom of the walls(with relief angle) which causes issues with rubbing. 

With "preserve z passes" checked, the direction of flow(top to bottom) is what I want, but the tool path seems to run twice on the sides. I'm assuming that this is the "Z pass" and the waterline portion.


So far to get this to run the way I want[maybe not the correct way] is to machine flats, then add waterline, then flats again. I love hybrid as it does almost everything I want quickly especially with a bullnose.

I cannot submit my holder but the part is machined with the square base on the bottom, and the part is layered ply that is about .25" oversized then machined down.

 

The, MOLD - ALT.STL

The, MOLD - ALT.x_t

[Guest]

Your part at this moment is sight unseen...just an observation on my part.

This toolpath(Hybrid) for me, it's always maddening.

I think I have geometry that could benefit from the path, yet I can never quite get the result I want.....this path seems to offer so much promise, yet seems to work on so little of the geometry I throw at it...

I usually end up going a different direction 

 

[Lord Wukits]

I was afraid of that, It's right there almost everything I need.... but then there are really silly inconsistencies causing a lot of "air" time. 

[Reko]

If you can, you should post a file here and let a few people share their opinions.

I have used hybrid quite a bit and had good success with it, albeit, on relatively simple surfaces/solids.

Every time I try to use it on extremely complex models, it falls short.

The other problem I have with it, is that the processing time takes waaaaaayyyyy to long, so again, on big, complex surfaces/solids, I usually go another direction straight away.

[Lord Wukits]

Reko, I've included the basic mold/model part in the first post. I work in solidworks, so I have both STL and X_T files(same part) for those who wish to try it. The flat square base  is obviously on the bottom(and locks into our thermoformer). At the moment tool of choice is a .500" bull endmill [I love that thing]. The "stock" I am working with is the same part oversized by about .25 of an inch on the top and sides.


If you would like, I can post the Solidworks part tomorrow, but thought STL should be sufficient. The part is pretty simple.

If i recall correctly I have the cut properties as "climb"[best with the ply I am working with] and "Zig-Zag". Stepover is set to .0625" on both Z and 3D.  .225" stepover on flats[included]. I would prefer the z passes "off"[but have them "on" to force machining to start at the top and work down] with the dropdown set to automatic(as it just seems to cut the same path twice). Smooth is set and minimal points is checked... minimal distance with  1" clearence from part, and vertical lead in @ .500" everything else at 0 with exception of 10* angle with a .1 height. 

I've even played with approx starting point, which has the endmill start at the top outer edge, then drop to the bottom of the wall and work its way up.



*note, I program in a solidworks assembly with proper orientation and fixtures/table modeled. I am aware that the part is "upside down". 

 

[Reko]

At first, I thought that would be the perfect candidate for Hybrid... if not for the tapered floor in the middle front.

If you have tapered walls and a flat floor, the step down can be set to .012" and step over to .250" which maximizes horizontal surface efficiency... but in the case of this part, the tapered floor needs a small step-over for a good finish too... can't have it both ways.

So again, for me, I'd rule out hybrid straight away because you need to approach this with different toolpaths for each area anyway... so you might as well get the greater control afforded in other toolpaths when you start breaking down each area.

[Lord Wukits]

A good finish isn't necessarily something I am after. I look for a "good enough" finish to sand/lacquer, and the .0625 stepdown  seems to be spot on for me. [we machine the molds out of ply]

The main issue I have is trying to change the flow of the cut. As I start with oversize rough molds I need to have the machine start the walls from the top, and work their way down. I can only seem to get that to work when I have preserve z pass 'on'. The moment i turn it off, it cuts from the bottom of the wall, and works up. THis causes rubbing, and if we have non-attentive operator, a fire.

Thank you for your input. It'll give me a reason to play with the other toolpaths.

[Reko]

4 hours ago, Lord Wukits said:

A good finish isn't necessarily something I am after. 

The main issue I have is trying to change the flow of the cut. As I start with oversize rough molds I need to have the machine start the walls from the top, and work their way down. 

Try this then.

Hybrid.mcam

[Lord Wukits]

It was not until I literally just looked at your part, that I now understand what  Cut Parameters > Step > Limiting angle actually means. You have yours set to 5*, I had it set to 90* thinking it meant something totally different. That prompted me to check out the help file, with your setting made everything click.


I'm a total Nuub. The issue was me and my assumptions of the setting I was fiddling with.

 

[Fred @ Slate Industries]

It works great on electrodes that are a cone shape with  ribs crossing through it

like you see in all kinds of plastic parts.

In this instance the one toolpath that does it all , Hybrid works with minimal tweaking