Toolpath To Geometry Associativity

How important is it to you?

For me it's often very important as some of the parts I program for prototypes get changed very frequently.

OneCNC does not offer toolpath to geometry associativity. Change the geometry in OneCNC and the toolpath is totally ignorant of the change. Everything must be updated manually in OneCNC.


Jon Banquer
Phoenix, Arizona

Lets see some pics of the parts you program...so far, theres not a shred of evidence that you have ever even put drill to steel once in your life, let alone advanced part Associativity... lets see some...

all the SMT (3d) toolpaths are associative, Holes are semi associative.

the stock (2d) are not.

If you use z level roughing for you're pockets and z level finish for your profile cuts, or to finish a pocket, then they are associative. as for how important it is, I would put it high on my priority list.

I've never worked with a system that had associative toolpaths with 2d type processes. I've read that its not all icing on the cake either, so far as editing, undoing, reassociating or regenerating the paths. Apparently there are pitfalls to be overcome in either system.

Take a simple example in OneCNC itself: preselection of a single surface for remachining with planar. Now this is nifty as hell when your focus is on that surface. But when editing, you do have to go back and reselect said surface(s) or else the process will be applied to the whole model as it appears within your selected boundary area, which may not be the same as the shape of only one surface. So because the association is not locked to the original surface, you've got to actually take additional steps to ensure that the proper area is being worked on. This would be one fault of having associativity in my mind.

If the geometry to be associated has to be visible whenever regenerating a process after editing for any reason, I can imagine that being a real bummer.

So while the nebulous concept sounds good, I would have to have hands on experience with such a system to know whether the implementation was as good as it sounds.

HuFlungDung, although I find it highly entertaining to watch you logically and methodically refute JB's constant barrage of insanity, I feel you may be wasting your time. You have to understand the 6 step process that leads to these posts by JB:

#1- Steal new issue of Modern Machine Shop from work.

#2- Flip through to see a new Gibbs or Mastercam X2 advertisement.

#3- Pick apart the ad with a fine tooth comb...."Toolpath associativity?? I wonder if stupid ONECNC has that...."

#4- Read ONECNC ad to compare features to other major CADCAM systems advertisements.

#5- Decide that ONECNC is an inferior product because he doesn't know how to perform the tasks that he sees in advertisements for other CADCAM systems.

And of course the legendary step #6- Visiting every website he's not banned from, and posting ridiculous claims about the software, along with personal insults towards anybody who doesn't agree with him.


There is no step 7. It doesn't matter what you say or how you say it. When you prove his claims to be false, he'll just go into hiding for a week while he repeats steps 3 through 5, then pop up for another entertaining rehash of step 6.

He's been doing this for years, with his negativity aimed at people and products all across the machining world.

Now he'll post a reply calling me a lying scumbag who's "buddies" with Cliffy, though he will never provide any proof of either claim.

In my experience, associativity is a very good thing. Associativity means two things (as far as I understand it, and as I have experienced it in regards to Surfcam and VisualMill/RhinoCAM).

First is the associativity of the geometry to the toolpath - if you modify the geometry within the app, you can easily update the toolpath without starting over. This is not automatic with Surfcam or VM, you do have to hit "regenerate" in either case. In Surfcam, I use this little, as I usally modify any geometry in Rhino and re-send it.

Second is associativity of the toolpath to the geometry... If you don't need to modify the geometry, but you do need to change the toolpath parameters, the geometry remains associated. So, complex surface or curve selection sets do not need to be painstakingly re-selected. This I use all the time.

I have used Surfcam with and without associativity, and the difference is night and day. --ch

all the SMT (3d) toolpaths are associative, Holes are semi associative.

the stock (2d) are not.

Click to expand...

However, the SMT toolpaths have tremendous limitations for use on 2.5D geometry, so you're stuck with using stock toolpaths for most 2.5D cases. (you can't even use cutter comp in SMT toolpaths)

My assesment of OneCNC

1. You get what you pay for. I think OneCNC's price is very fair.

2. It is very easy to learn. No kidding, I was cutting parts after a 2-3 hours and no training.

3. Lifetime updates (not upgrades)

4. OneCNC is probably the fastest CAM software that I have ever used for generating an initial toolpath on 2.5D geometry.

-the tradeoff is less efficient toolpaths and poorly organized offsets that can bite you in the rear. I can't possibly think of a more dangerous way to handle work and tool offsets.

5. I don't like how OneCNC's marketing campaign compares their product to Mastercam. Simply put, it is misleading to the consumer.

-I'm not trying to say anything bad about the software...it is definately a good program for it's price. If you ignore price, OneCNC comes up short compared to the systems in Mastercam's market. But seldom do people ignore price.

Associative toolpaths...I used Pro/Man before I started working for myself , and I really miss associative toolpaths.

BTW, I'm selling my license of OneCNC XR2.