topic Re: Cutting 2D arcs with 1 move in PowerMill Forum

Cutting 2D arcs with 1 move

Anonymous — Fri, 23 Mar 2018 19:11:42 GMT

Hi all,

Is there a way (that I'm missing) to get 2D arc paths to output 1 G02 or G03 move? I'm roughing a 1 in. hole in multiple steps to depth and following that with a cutter comp pass. I've changed parameters many times and I still get 2 or 3 moves to do 1 circle. Some of the moves are small enough that the machine control will alarm. I end up editing my code to get the desired results. I'm using "2D Curve Profile" with arcs I imported from PowerShape.

Help,

John

Thanks in advance

Re: Cutting 2D arcs with 1 move

precicam — Sat, 24 Mar 2018 04:33:30 GMT

@Anonymouswrote:
Some of the moves are small enough that the machine control will alarm.

How come? How small are these moves? Anyways, you can try changing the postprocessor setting that says something like "allow complete circles", along with "fit arcs" in point distribution and max out the tolerance factor under it. Haven't tested it though.

Re: Cutting 2D arcs with 1 move

Pradipio — Mon, 26 Mar 2018 10:24:13 GMT

Hey @Anonymous,

Thanks for posting.

Can you please share your project and other details it will make us to understand that issue properly.

Thanks in advance.

#PM

Re: Cutting 2D arcs with 1 move

rafael.sansao — Mon, 26 Mar 2018 10:57:52 GMT

I reported this problem to Autodesk on 03/2016. But Autodesk does not solve customer problems! we suffer with this problem every day!

ID: 12332930

Re: Cutting 2D arcs with 1 move

Pijetro — Mon, 26 Mar 2018 11:33:18 GMT

Is the alarm happening on an Arc in and Arc out move, or mid segment?

Re: Cutting 2D arcs with 1 move

rafael.sansao — Mon, 26 Mar 2018 11:36:54 GMT

Mid segment. Powermill creates points very close and the controller returns error.

Re: Cutting 2D arcs with 1 move

LasseFred — Mon, 26 Mar 2018 12:10:41 GMT

will it work with 2D curve toolpath. with a pattern and arc fit the pattern?

Re: Cutting 2D arcs with 1 move

rafael.sansao — Mon, 26 Mar 2018 12:41:22 GMT

The problem is with 2D curve toolpath.

The sample project is attached.

Re: Cutting 2D arcs with 1 move

LasseFred — Mon, 26 Mar 2018 12:51:04 GMT

Look at this.

Re: Cutting 2D arcs with 1 move

rafael.sansao — Mon, 26 Mar 2018 13:01:03 GMT

Error: Tool radius too large.

Re: Cutting 2D arcs with 1 move

iamcdn79 — Mon, 26 Mar 2018 13:15:29 GMT

Deoes this work? Toolpath 1_1

Re: Cutting 2D arcs with 1 move

Pradipio — Mon, 26 Mar 2018 13:16:23 GMT

Hi @rafael.sansao,

please make sure you are using correct toolwear option.

there are two type of toolwear as below.

Type — Select the type of cutter compensation:

Full radius — The machine tool compensates for the entire tool radius.
The machine tool compensates for the tool radius and PowerMill adds arcs to concave corners to protect against the machine tool rejecting the toolpath. The Minimum Radius field controls the size of the arc in corners after a tool radius offset. This enables most machine tools to accurately represent the contour in concave corners.

This is often called Part Line Programming.
- When using Full Radius, PowerMill can't carry out most collision avoidance checks as the tool diameter isn't known.
Tool wear — PowerMill compensates for the nominal tool radius and the machine tool compensates for the difference from nominal.

Tool wear is similar to Full radius, in that the machine tool compensates for the tool radius. PowerMill adds arcs to concave corners to protect against the machine tool rejecting the toolpath. Tool wear corrects the limitations of the Full radius option as PowerMill can use the nominal tool size to check for collisions. Last-minute correction for the actual tool size is applied on the machine, which is where the actual tool size is known. Provided that the actual tools are always smaller than the nominal (how tool wear normally works), then PowerMill can guarantee that toolpaths will not gouge. However, extreme tool wear may result in material being left unmachined.

Minimum radius — Enter the minimum radius of concave corners after applying tool radius cutter compensation. This avoids small arcs which some machine tools have difficulties processing. This option is available only when you have a Type of Full radius.

Re: Cutting 2D arcs with 1 move

rafael.sansao — Mon, 26 Mar 2018 13:52:11 GMT

Worked up to 5.24mm radius.

It was to work up to 8.5mm radius

Re: Cutting 2D arcs with 1 move

rafael.sansao — Mon, 26 Mar 2018 13:53:46 GMT

Of course I've checked those options.

Write the program and try running on some machine. It will never work!

Re: Cutting 2D arcs with 1 move

Anonymous — Mon, 26 Mar 2018 15:05:34 GMT

Hi all, thanks for responding. I agree with rafael.sansao. I have tried using "Pattern Finishing" and "2D Curve Profile" and in both whether I used a D value or not the code will come back with several moves (some as small as a several tenths or a few thousandths) that will generate an interference alarm on the control.

If my screenshot works, I'll follow it with the code.

Thanks John

Re: Cutting 2D arcs with 1 move

Anonymous — Mon, 26 Mar 2018 15:10:47 GMT

This is what the code looks like. This is a roughing pass and the moves are small, but not as small as some.

Re: Cutting 2D arcs with 1 move

Pijetro — Mon, 26 Mar 2018 15:20:51 GMT

Ok.

Can we please backup, and make sure that the original ops issues are not the same as Rafaels?

Perhaps the original op might want to post up a project, and how he wants to approach the machining?

Re: Cutting 2D arcs with 1 move

Anonymous — Fri, 06 Apr 2018 16:59:58 GMT

Hi Pijetro, Is the screenshot and code I posted enough or are you meaning the actual project?

Thanks,

John

Re: Cutting 2D arcs with 1 move

Pijetro — Fri, 06 Apr 2018 17:26:10 GMT

Actual project..

I'm suggesting the your issues might not be the same as the ones posted above me.