5th axis toolpath

[bet338]

Hi everybody,

I need help with a 5 axis toolpath I am

trying to make around the inside of the part

shown (at least I hope it is). I want to use a 3/4" x 45 deg. dovetail cutter coming in from the top of the part to make the undercut following the contour of the window. This will be cut on a Haas VF-5 trunnion. I spent most of

yesterday afternoon trying to make this work

and I'm just as lost as when I started.

Thanks

 

[MACHINEMASTERG]

no picture here ???

[bet338]

Ok,read the instructions,must have done it wrong.

[crazy^millman]

Ok let me see if I can help you out here. You need to separate the surface you want to cut. Since you are planning on using a dovetail cutter. I would probably use a curve 5 axis toolpath to do this. Will require a little work on your part, but should give you the best results.

 

Step 1: Copy the surfaces you want the dovetail cutter to be cutting do a separate level say 100.

 

Step 2: On Level 101 create curves from the surfaces.

 

Step 3: Take the chains that are what will be your vectors to control the tool alignment or in this case they will control your trunnion table. Vectors in the simplest terms are lines that you want to represent the center line of the tool as the contact point of the tool adjacent to the surface it is cutting. The more of these you have the cleaner the cut will be and the better the part will look. My rule of thumb is minimum of 5 on arcs smaller than 1" 9 on arcs 1" to 3" and the bigger I just use my best judgment. On lines it really depends of what I want to do with the tool. If I want to keep the tool normal to the cutting surface most time 3 will do on a straight line. If I want to start at one angle and end at another angles then again I just use my best judgment.

 

Step 4: Create the chain to drive the operation. The cool thing about curve 5 axis is you can have a lead in and lead out all in the same chain and it will go through the motions just as you want. Now I put this chain on a different level and make it a different color. Now that you have this chain you need to decide how you are going to drive the cuter. If you make the chain and offsets of the contact distance you are pretty much done. This way is a lot more work, but IMHO the most accurate. If you are using the edge of the part or something on the surface as chain that is constant then you made life very easy. In the operation you just change the offset and the vector depth and now you have a toolpath to drive a tool that is not supported too well in Mastercam IMHO.

 

If you want to send me a file zipped I will be glad to help you out.

 

HTH

[bet338]

Ron Teh Crazy Millman,

thanks for the reply. Would I use the zip2go utility to send it?

[crazy^millman]

Yes that will be fine.

[bet338]

Ron,

You got mail.

[crazy^millman]

Ok what a surface to tru to cut with a dovetail cutter. I am going to run some errons and get some lunch be back in about an hour and will give you something to work with then.

[bet338]

Ok,thanks

I'll be gone by then. 5:30pm EST. is my quitting time. I'm still trying and starting to almost look like what I want. As to the dovetail,thats

the only way I see I can get to the cut. I'm open to suggestions.

[crazy^millman]

After looking at this file yes the dovetail cutter is your only option. Need to get one with a .01 radius on in. I would probably have a custom one made so it could cut the flat wall 90 deg to the surface you are trying to cut. You are going to have to use Vectors to control this tool the correct way. Problem is you have to create them all. I tired about 10 different multiaxis toolpaths and the only one that will work is Curve 5 axis and it just requires some work when using a tool like this. I tired creating a few surfaces to use to help make the lines. I will mess around with it maybe tonight or tomorrow, but if you could create a surface 45 degress normal to the surface you are cutting you could then make 100's of points along the top and bottom of that surface. Then draw your lines between those points and your vectors are done. I will let you know what I come up with. I emailed you back the file with a start of what I am talking about.

 

HTH