2021 CAM Challenge - Continuous machining around a contour using X,Z and Rotary axis

[Anonymous]

Hello Fusion 360 community,

Ready for a hard one?

I come across this in the field occasionally and I've never been able to figure out an elegant way to program it using CAM software.

The part needs to be machined around the whole entire contour in one continuous motion utilizing the X, Z and Rotary axis moving independently or simultaneously depending on the area of the part it is machining.

Think of the machining operation as a shallow scribe around the whole part using a 1/16 ball end mill.

Normally I would use the trace operation for the flats and contours, but I need the part to index the rotary while it is machining, not just rotary step, machine, rotary step machine.

COORDINATE SYSTEM

For the flat runs of the part, the table can move X linearly but when it comes to the round portions of the part, the rotary must move along with the X and Z to keep the end mill normal to the surface at every point along the path.

I've created some rudimentary models to help with the explanation. See photos below:

If I've left any details out, please let me know.

I can't wait to see how the experts handle this!

Thank you,

Brayden.

[daniel_lyall]

Have a look at the rotary toolpath.

Example attached.

[Anonymous]

Hi Daniel,

Thanks for the response..

The example seems to be something different? (Cardbox)

Maybe attached the wrong thing? 🙂

[daniel_lyall]

here you go

[engineguy]

@Anonymous 

Well, @daniel_lyall  has shown you the Rotary toolpath using a 4th axis as you put forward for one solution.

Always up for a Challenge 🙂

My answer is there is no need to use a 4th axis at all, I have done this sort of machining many times over the years, long before I had any 4th axis or fancy expensive CAM, it is just a simple 3 axis job done using whatever you like for the holding, can be a vise or a Lathe chuck on the machine bed and then simple 2D contour using a 6mm Flat End Mill to run around the shape for all the flat stuff and then just use a small Slotting cutter as shown in the attached file, again a simple contour selecting the bottom edge of the slot and setting a Stock to leave of a -0.397mm to move over into the material.

This could even be done on an old 1942 vintage manual "Copy Mill", no CNC required !!(Yes, I ran one of those for a while) !!

Basically about as simple as it gets IMHO, no "Challenge" with that one, couple of 2D contours and no exotic "pay extra for" toolpaths required 🙂 🙂 🙂

You have anything that is actually a "Challenge" for the Community  ? 🙂 ? 🙂 ? 🙂

Only joking 🙂 🙂 🙂 Oh, and no, I am not an expert, just old 🙂

BTW, as for the Box top if it is the Fillet around the top edge you want to do then just go buy a Rounding tool and run round it using a 2D Contour, no 3D stuff required 🙂

Don`t know if you were ever taught the old Nemonic (This is before the Rock Band used it) of KISS that was drummed into us as Apprentices

Keep

It

Simple

Stupid

Stay Safe

Regards

Rob

[Anonymous]

Hi @daniel_lyall ,

Still not seeing the rotary example.. Can you please attach it?

@engineguyThis method you've outlined looks great and is totally an even simpler way to do this! I appreciate the time you spent on making this program, and it definitely showed me something to keep in the machining arsenal..

However,

I was not completely transparent with what I'm trying to do with this part to try and avoid some confusion.

This style of tool path I'm trying to generate is actually for Laser Welding, and not Milling. Its been my experience when I tell a machinist programmer I'm trying to generate a tool path for laser welding, they quickly shut it down 😉

Anyways, the laser head has a standoff distance of ~3.0" from the part, and the head is stationary (much like a vertical machining center) It would make more sense to think of this as running the job with the tool offset 3" from the surface of the part.

I'm thinking the Rotary tool-path @daniel_lyall is trying to show me might be the correct solution... just haven't got a chance to see it.

Does it really cost an extra $1600 to do these types of tool-paths? What in the world.. 😉

I wonder if I will even be able to view the file without having the machining extension on my account.

I appreciate the help from you guys.

[engineguy]

@Anonymous 

Aha, OK, now I see the challenge alright 🙂

Your problem will be that I am assuming the Laser Head is fixed, by that I mean it can not move up and down in the Z axis like a 3 axis Mill would, if that is the case then the Rotary that Daniel @daniel_lyall  has done relies on the head moving up and down as the part rotates in the 4th axis so that wouldn`t work as it is.

So, unless you are able to move the Laser head up and down as in a VMC then I think it is a doomed project 😞 😞

Yes, that is the sort of price they are asking for the Extensions, don`t bother looking at what they want for 5 axis continous, would really upset you some more, somewhere around another $2500 !!

As for being able to open and view the Rotary file from Daniel that will work fine, you should also be able to run the simulation although the simulation shows the tool/cutter rotating around the part whereas in real life the Part rotates and the tool/cutter remains static, onlly moving up and down in the Z as in a VMC.

What you will not be able to do is Edit the file to perhaps change something !!

Stay Safe

Regards

Rob

[Anonymous]

@engineguyWhat a world we live in! They even charge for plastic bags now! 😉

The Laser head does have a Z-axis just like a Milling machine does, so I think it will work as @daniel_lyall is proposing.

On another note,

Have you tried posting to Tormachs pilot hub?? Its free to create an account.

I just figured this out yesterday. It will actually show a tool path with a rotating axis for the rotary..

I was really impressed!

https://hub.pathpilot.com/

Check out the attached video.

[jedQB94J]

Hi @Anonymous ,

Is it a toolpath like this you want?

Thanks,

Jacob

[engineguy]

@Anonymous 

If the Head will move up and down in the Z then, yes, the Rotary from Daniel @daniel_lyall and or @jedQB94J should work fine 🙂

Why oh why do we have to prise information from you, you started off with a 1/16 Ball nose end mill, then it becomes a Laser that is fixed at 3.0" offset, now it goes up and down like the Z axis on a VMC ???

What next ? Does it have to done in Zero Gravity ?

Complete time waster, new or not no excuse for your behaviour here, I for one will not be looking to answer any future Posts of yours, the other guys are welcome to you !!!!!

Meantime

Stay Safe

Regards

Rob

[Anonymous]

Hi @jedQB94J

Thanks for your response.

I believe this is what I'm looking for.. could you share the example?

Thank you much!

[Anonymous]

@engineguy 

Thank you for all your help.

I learned something valuable from your example about side contours and about rotary toolpaths so I thank you again for that.

One day I hope to be a better teacher than you. One that does not forgot what it's like to be new and learning.

Have a nice day.

Brayden.

[daniel_lyall · Accepted solution]

@Anonymous The forum is being a F____ at the moment.

On this forum, you will get help even if it is for a laser or a chicken, it is Gcode after all and if you know how to lie to a machine there is no issue.

You basically just need to use a sketch or a surface to get a single toolpath.

[Anonymous]

@daniel_lyall

This was amazing and exactly what I was looking for!

Thanks for the help.

Very much appreciated.

Guess I must buy the machining extension now ¯\_(ツ)_/¯