Haas VF4 Rapid Moves vs. CAMWorks Rapid Moves and Post Processor Issues

Hello Everyone,

We have a small machine shop with several CNC machines, and we're having some issues with how the CAMWorks simulation produces a rapid move and how our VF4 or VF2 machines actually move. I'm hoping someone here may know what we need to do to solve the problem.

As a small disclaimer, I'm not a CAMWorks user, I am just trying to see if I can help our engineers solve this issue. I understand what is going on, but if anything needs clarified, please ask.

Now, on to the issue. When we create a tool path in CAMWorks, it will produce rapid moves that first move to the preset Z height (skim height?), and then move diagonally to the next location. What happens when we actually run the program in the Haas machines is that the tool will move up properly on the Z axis, but when it moves on the X and Y axes, it runs both of them at the machine's rapid move speed, and since both of the axes are moving at the same speed, it is not a straight line and ends up crashing. This has caused us to override our rapid speed in production, and slows us down tremendously. Even with slowing the rapid down, we still risk crashing and it has caused a lot of uncertainty with our programs.

I've included a sketch of the issue. You can see the green line shows the path that CAMWorks intends to make, but with the rapid speeds being the same on both the X and Y axes, it does not end up moving in that straight line. I added a "part" to the sketch so you can see how this affects us. CAMWorks sees the move as being clear of the part, but the actual move when running the program ends up causing a crash.

Again, I'm not a programmer or machinist, so if anything needs clarified, please let me know!

Thanks

Attachment 243708

Firstly, I'd ask haas to look at the machine, your axis should move at the same rapid movement speed,

Secondly, you could always get your reseller, or whoever wrote your post processor to output the X &Y on different lines, this way you may avoid going throughout the middle of the Job,

Thirdly, CAMWorks is the second cam company to have truly integrated machine simulation, it may be worth the cost of machine simulation to check your cnc code before it even gets put into the cnc machine....

Thanks for the reply, Jame5m28.

If I were to go with your second recommendation, would I be able to simulate this in CAMWorks, or would it still move diagonally? I would be fine with sequential rapid moves on each axis (move full Z, move full X, then move full Y) if it can be simulated in CAMWorks. I just want to make sure that what our simulation shows is exactly what our machine does.

If we have to in the future, we may purchase the virtual machine simulator, but I'd like to try to work this out in the software. We have never had a crash with normal feeds, we've only had this one rapid moves issue.

It would still move diagonally, the standard simulation only simulates the CL data, (cutter location) so it is trying to tell your machine to move diagonally! It's telling it to move in x&y, it's just your machine. That seems to move incorrectly!

There is one other way, depending on the version of camworks you are running,

If you expand the operation, you can "edit the tool path" this would allow you to split your rapid lines down, this should simulate in camworks.

Rapid on a Haas moves both axi at that same time at the top speed it can. So if its going from X0 Y0 to X10. Y2. it would get to Y2. much faster and stop moving in Y while still moving in X. Feed will move both to get to the location together. That's the way our Haas machines are and it spells that out in the manual (too much typing to quote it, sorry). So the Haas machine is doing it correctly, just not as might be expected.

I have gone over some of the CAMWorks setting to see if there is an easy adjustment to the simulation. No luck. So that suggestion of the full machine simulation might be the only way. I have no experience with that, however.

Camworks don't do that, the best way is to play with the machine parameters to make "linear rapids", you don't lose machine time with this, the x axis will travel at maximum rapid traverse rate to the position and y axis feed will adjust it speed to arrive at the same time, This way it makes exactly the same thing than simulation. On my Fanucs the parameters is called linear rapid and i'm sure Haas machines have an equivalent...

We found that we can change from dogleg rapids to interpolated rapids in our Haas machine, so now we're able to simulate in CAMWorks exactly what we're going to be running in our machine.

But... We have a new problem. The Haas machine seems to just turn all G0 codes into G1 codes. If our operators override the feed rate of the program, it also slows down the rapid moves. Any thoughts on this?

It's probably going at its maximum feed rate (on our Haas VM2 its 500 IPM).

i see this somewhere for haas
Parameter 315:23
This is the one you changed ???

Our engineer and one of our machinists took care of the change so I'm not sure of the exact parameter, but I can find out.

Is there more to this parameter that we're unaware of, assuming we're talking about the same one?