Advice for Toolpath, Please

[Bill H 8]

I'm working on a part that's approximately twelve inches square.  The vast majority of the area is flat, but there are about twenty small bosses (about 0.5" square) that protrude from it.  I'm trying to find a toolpath to finish the flat area.  I've tried a number of the pocketing toolpaths, but don't like the results.  Specifically, the toolpaths end up looking like a drunken sailor wandering all over the part with no rhyme or reason.   Except to avoid the bosses, I want the tool to always travel in the same direction.  Also, instead of picking up the tool to avoid the bosses, I want to 'steer' around them.  Any suggestions?

[crazy^millman 5,738]

Leave stock on the bosses with Pocket and then finish them with Contour the way you want it. I will normally finish the floor and then I will ramp into the bosses and ramp out of the bosses to prevent the tool from dragging the floor.

Sorry read that too fast. Same direction will have to try Leon's suggestion, but any toolpath will have to avoid the bosses so not sure what to tell you.

[Leon82 387]

I using use a highspeed path than finish with a pocket path. You can use zigzag in old pocket for straight lines

[So not a Guru 447]

Opti-rough, in Model Geometry leave stock on the walls and none on the floors.

[#Rekd™ 1,388]

Yes use Pocket to finish and offset the outside chain to allow for the tool to fully cut. 

[neurosis 1,992]

11 hours ago, Bill H said:

I've tried a number of the pocketing toolpaths, but don't like the results.  Specifically, the toolpaths end up looking like a drunken sailor wandering all over the part with no rhyme or reason.

That has to be the best explanation of mastercam pocketing tool paths that I've ever seen.   

[Bill H 8]

Thanks for the replies, but none have addressed my core concern, namely, how to get a toolpath that moves in only one direction and doesn't move all over the part in odd ways leaving ugly snail trails in its wake.

[AHarrison1 26]

9 minutes ago, Bill H said:

Thanks for the replies, but none have addressed my core concern, namely, how to get a toolpath that moves in only one direction and doesn't move all over the part in odd ways leaving ugly snail trails in its wake.

I used pocket with rough motion set to zigzag. 5 options down there is one way.

[Bill H 8]

AHarrison1:  What do the various colors in your graphic represent?

[AHarrison1 26]

Just now, Bill H said:

AHarrison1:  What do the various colors in your graphic represent?

The green is lead-in motion, red is lead out, blue is cut motion and the purple is transition from rough to finish pass.

This is part of the advanced Toolpath Display which became an option in 2020, I cant remember if this was in 2019 or not.

 

[Thee Byte™ 779]

4 minutes ago, Bill H said:

AHarrison1:  What do the various colors in your graphic represent?

Red and dark green are lead in /lead out/entry motion, blue is toolpath, yellow is rapid,light green is geometry

[Leon82 387]

You can always draw your own pocket path geometry

[crazy^millman 5,738]

1 hour ago, Bill H said:

Thanks for the replies, but none have addressed my core concern, namely, how to get a toolpath that moves in only one direction and doesn't move all over the part in odd ways leaving ugly snail trails in its wake.

Not going to happen. The algorithm is written to do shortest most efficient paths. What you consider drunken sailor has a purpose and reason. I drew your describe shape and put 20 random .5 round bosses it in. I use a 3/8 endmill one way and still got snail movement. Nature of the beast. The tool has to get into and out of the cuts and your trying to not allow that to happen. Why is that? What does this do to hurt the manufacturing of the part? I think your chasing ghosts for no reason just to chase something. Why? How would you get the tool in and out of the pocket? What is the exact purpose of this exercise?

[DUM1 79]

when im after a pleasing look i go with true spiral from inside to out , start at center , there is a lot of "air time " but it comes out uniform, and aesthetically pleasing .

[crazy^millman 5,738]

1 minute ago, DUM1 said:

when im after a pleasing look i go with true spiral from inside to out , start at center , there is a lot of "air time " but it comes out uniform, and aesthetically pleasing .

Great suggestion, but unless the tool is lifting you still have snail trails in the inside shape in the Triangle section.

[DUM1 79]

there were a few "snail trails , as you can see the ones that aren't uniform but there were only a few and they too were kind of uniform and by playing around with it a bit i could have got it closer to complete uniform , but yes there are almost always some kind of darn its, that you just run out of time on and have to move on

[crazy^millman 5,738]

2 hours ago, DUM1 said:

there were a few "snail trails , as you can see the ones that aren't uniform but there were only a few and they too were kind of uniform and by playing around with it a bit i could have got it closer to complete uniform , but yes there are almost always some kind of darn its, that you just run out of time on and have to move on

That was kind of my point to Bill.

[Leon82 387]

Morph is good for making symmetrical patterns

[Bill H 8]

crazy^millman:  You're absolutely right - snail trails and drunken sailor motion in no way affect the function of the part nor the ability to machine it.  My goal is strictly to improve the aesthetics of the part.  If we look at your example with the round bosses, what I would like to see is a toolpath parallel to X.  When one of the bosses is encountered the tool would follow the boss's perimeter until continuing along its original course.  

DUM1: I like this!  The few snail trails are fairly symmetrical and don't bother me.  Are there any secrets to getting the toolpath to come out like this?

[crazy^millman 5,738]

3 hours ago, Bill H said:

crazy^millman:  You're absolutely right - snail trails and drunken sailor motion in no way affect the function of the part nor the ability to machine it.  My goal is strictly to improve the aesthetics of the part.  If we look at your example with the round bosses, what I would like to see is a toolpath parallel to X.  When one of the bosses is encountered the tool would follow the boss's perimeter until continuing along its original course.  

DUM1: I like this!  The few snail trails are fairly symmetrical and don't bother me.  Are there any secrets to getting the toolpath to come out like this?

Excellent answer and trial and error is what it takes sometimes to dial it in. All else fails I draw the motion I want for a pocket then drive a contour toolpath no comp. Oldscool, but like we use to do it when I learned to program in the late 80’s. Make the shape then offset the radius of the tool and then make offsets of that shape from there. Once you have the base pattern figured out you can write a program by hand in 15-20 minutes. 

[heavychevy2155 132]

You could do a surface finish parallel to finish the floors and use the island faces as check surface.  You could do a zig zag or one way and even change the angle for a unique look.  You would still need to use a seperate contour toolpath to finish the islands though.

T.mcam

[kccadcam 261]

As Leon82 said, Highspeed pocket works well.

 

[metalmansteve 209]

Not sure I'm buying the 'algorithm does the most efficient path' stuff.  

Maybe there was a better way but I saved a lot of cycle time creating my own toolpath geometry on this shape.

 

[Joe777 4]

Surface High speed(Horizontal Area)

I like to use for flat area's. Very efficient. Recently I cheated by using  "2d dynamic mill" for finishing purposes. You need to filter it to get nice arcs. (Is there any other finishing tool path like that?)

Pocket has too many (lead in/lead out) leaves marks.

 

 

[JB7280 61]

On 1/18/2021 at 10:36 PM, Joe777 said:

Surface High speed(Horizontal Area)

I like to use for flat area's. Very efficient. Recently I cheated by using  "2d dynamic mill" for finishing purposes. You need to filter it to get nice arcs. (Is there any other finishing tool path like that?)

Pocket has too many (lead in/lead out) leaves marks.

 

 

I applied this to a part I'm working on right now, and I really like it.  Although I don't love the entry/exits, but i imagine I can get those how I like them with some tweaking. 

 

I always forget about the possibility of using 3D toolpaths on 2D surfaces.  What other 3D toolpaths have this type of functionality?