Fillet issue with wire

[bamavick]

I am having an issue with our wire machine wanting do a full circle when it comes to certain fillets. It is happening when the offset is applied at the machine. On MasterCam its set to (in control).

The only way around this is to have MasterCam set to (in computer) and call out the gcode with the offset already applied. Anybody have a idea or have seen this before. I'm sure there is some sort of filter I can use to prevent this but just not sure what to do??? Oh yeah, it seems to only be on small .008" or .010" fillets and so far its been on shape with a lot of small ridges, like a bleacher section.

 

Thanks!

[Del.]

Do you mean the wire is actually coming out of the burn and back in?

[bamavick]

What its doing is going outside the geometry which is causing a gouge in the steel. As its cutting or dry running it is tracing the offset around the g code from the .iso file and thats when you see it. We are using Robofil Charmilles machines and have never had this problem on similiar shapes before.

[Del.]

Is it possible you have some type of fishtail corners set in your parameters on Mastercam?

[bamavick]

Fish tail is checked in my control setting in the corner tab. This has always been checked as far as I know in all previous versions of MasterCam we have used. One thing I did notice was checked that wasn't in our previous versions was the End point checks in the Arc tab. Would this cause problems like that? I am not familiar with what that does exactly.

 

Another thing that doesn't make since is that it doesn't do it on all the corners, it can be a ridged top with .010" r. connecting the top ridge to the bottom ridge and their could be 50 of those just alike and it will choose to do this on just one fillet out of the whole bunch. Makes you want to pull your hair out!

[Del.]

Fish tail is checked in my control setting in the corner tab. This has always been checked as far as I know in all previous versions of MasterCam we have used. One thing I did notice was checked that wasn't in our previous versions was the End point checks in the Arc tab. Would this cause problems like that? I am not familiar with what that does exactly.

 

I am not sure but in mine it is unchecked on the end point checks.

 

 

In your wirepath parameters what are your corners defaulting to?

[bamavick]

If I am looking in the right place that you are talking about they are all set to Conical.

[Del.]

Is this straight burns or 4 axis. In your control def under arcs are your arcs set to "delta start to center"? Is allow 360 degree arcs unchecked?

[bamavick]

straight burns, control def is set to delta start to center and yes allow 360 deg. arcs is unchecked

[Del.]

Email me the file as an X4 to [email protected]. I am curious if you don't mind.

[bamavick]

I have no problem doing that. I did just get through running test cuts on both of our Charmille machines and the Robofil is the machine that is causing the problem. Our other machine is a Charmilles Cut 20 and it cut the part just fine with no problems.

[Del.]

One thing I saw was the radius in the corners were .001, with a .003 straight line after that. The only way I could cut this was to turn Optimize on so it would ignore the corners or trim the corners together. Are you using .002 dia. wire to do this? There must be a setting on one of your machines that overrides a radius smaller than half your wire diameter.

[bamavick]

Sorry, that was a piece of the shape that I manipulated to cut a test and put the startpoint on the outside. The wire comp is actually on the inside of the shape. We use .010" wire.

[Del.]

In that case I don't really see anything wrong with it. Has to be machine like you said.

[bamavick]

Yeah I think so to... Do you think since its such a repititious movement that if it starts out a small problem and then just compounds till it has a bad movement on one of the serrations and then resets itself and starts all over again. Thats the only since I can make of it since it only happens on these type of shapes.

[Colin Gilchrist]

Are you 100% sure your geometry is correct? I've had issues with Wire when there were very small gaps between the endpoints of entities (.00001-.00004). The gap was less than the chaining tolerance, but it would cause problems when interpolating arcs. This might not be the problem at all, but I thought I would mention it.

 

Try using 'Analyze > Distance' and set your precision to 8 decimal places. If there is a small gap between your arc and line endpoints, delete the arcs and use the fillet command to create new ones...