Facing cuts air, no matter what

[SlaveCam]

How on earth do you make facing so that the last pass won't cut air (zigzag or unidirectional)? I can't use dynamic because there's not enough memory for the toolpath. I try changing the parameters but each time a. the first pass takes too much or b. the last pass cuts air.

 

Thank you!

[Guest]

Either draw your lines and control the cut or you can trim the toolpath

[SlaveCam]

Aye

[guitar]

pocket

T.mcx-9

[AMCNitro]

Its usually better to just draw the lines and use countour with comp off.  You have more control.

[mkd]

to save memory bump up the filter tolerance on Dynamic face??

[Eric@HorsepowerInc.]

How on earth do you make facing so that the last pass won't cut air (zigzag or unidirectional)? I can't use dynamic because there's not enough memory for the toolpath. I try changing the parameters but each time a. the first pass takes too much or b. the last pass cuts air.

 

Thank you!

Not enough memory? What size tool? For an excellent facing pass, set the tol. Way high, .005/.01. 70/30% filters, big min t-path rad.

[mikenaturalice]

Its usually better to just draw the lines and use countour with comp off.  You have more control.

I've never understood this logic personally ^. The facing toolpath always works fine for me... How much time are we talking here (wasted cutting air)? I guess if you are routinely facing 4 foot lengths or so, sure you don't want to cut air for that much, but in "regular" size blocks (3,4,6,10" etc) whats the big deal? I know someone will chime in about production and how much time you save by eliminating that one extra pass, sure I get that, but glad that isn't an issue for me! 

You said you don't have enough memory, holy crap that must stink! 

[guitar]

I've never understood this logic personally ^. The facing toolpath always works fine for me... How much time are we talking here (wasted cutting air)? I guess if you are routinely facing 4 foot lengths or so, sure you don't want to cut air for that much, but in "regular" size blocks (3,4,6,10" etc) whats the big deal? I know someone will chime in about production and how much time you save by eliminating that one extra pass, sure I get that, but glad that isn't an issue for me! 

You said you don't have enough memory, holy crap that must stink! 

 

 

Keep in mind that facemills are generally large diameters and clearing the part of the radius of a facemill can take alot of extra time for each pass. Yeah, if your are doing 5 aluminum parts it may be no big deal. If you are doing 1000 steel parts, that can be a huge cost.

[AMCNitro]

I've never understood this logic personally ^. The facing toolpath always works fine for me... How much time are we talking here (wasted cutting air)? I guess if you are routinely facing 4 foot lengths or so, sure you don't want to cut air for that much, but in "regular" size blocks (3,4,6,10" etc) whats the big deal? I know someone will chime in about production and how much time you save by eliminating that one extra pass, sure I get that, but glad that isn't an issue for me! 

You said you don't have enough memory, holy crap that must stink! 

You're lucky you didnt have to deal with my last boss, if you took one extra pass he'd have something to say about it, and depending on his mood he'd either tell you "Hey, com on, get rid of that pass" or  just "GET RID OF THAT F......G PASS IDIOT!!".  In truth he does have a point, if you have hundreds of parts air cutting can add up.

[AMCNitro]

I've never understood this logic personally ^. The facing toolpath always works fine for me... How much time are we talking here (wasted cutting air)? I guess if you are routinely facing 4 foot lengths or so, sure you don't want to cut air for that much, but in "regular" size blocks (3,4,6,10" etc) whats the big deal? I know someone will chime in about production and how much time you save by eliminating that one extra pass, sure I get that, but glad that isn't an issue for me! 

You said you don't have enough memory, holy crap that must stink! 

The facing on the 1st pic is going to be a lot faster than the one on the second ic

[Rstewart]

You just need to set the parameters in the facing options.

 

Maybe X5 didn't have enough options, I can't remember

 

 

[guitar]

You just need to set the parameters in the facing options.

 

Maybe X5 didn't have enough options, I can't remember

 

 

FACING.JPG

 

 

That is cutting air. The idea is not to leave the part.

[mikenaturalice]

The facing on the 1st pic is going to be a lot faster than the one on the second ic

You are right, but if you play with the options in facing you can make it pretty much act the same way as the first one. I get what people are saying about it adding up over hundreds or thousands of parts, but I think you can get the face to perform very well if you just play with options.

I use to let it 'default' to leaving the part completely at the end of stroke, but unless you are trying to achieve something special with the finish there is no need. As long as the radius of the cutter machines the very far corners it does not have to completely leave the part if you use the high speed loops option. I don't think there is anything wrong with drawing your own lines and programming a contour to face with, I just don't see it as necessary for the most part. A very long time ago (maybe X2 or X3) a guy said this same thing "the facing doesn't work right so i draw my own lines", I just called BS on that. It will do what you want if you play with options. Yes, if you are trying to shave 1-2-3 seconds off each part, ya maybe with your own lines and using contour you can do that. Fortunately for me I am not in that position! 

[mikenaturalice]

You're lucky you didnt have to deal with my last boss, if you took one extra pass he'd have something to say about it, and depending on his mood he'd either tell you "Hey, com on, get rid of that pass" or  just "GET RID OF THAT F......G PASS IDIOT!!".  In truth he does have a point, if you have hundreds of parts air cutting can add up.

No, I think we might have had the same boss at one time! HAHA. Seriously though, sometimes it is faster to let the machine/cam/programmer do their thing and get the part cutting instead of tweaking every single feature to save a minute here and there. Yes, you get in production then you start looking for those time savings, but for 1-2-50 parts it often does not offer any payback (unless you really have the programming dorked up!).

[Rstewart]

I didn't quite understand the question.

 

Guitar:   2" facemill that stays in the cut while using the standard Facing without extra geometry

 

[AMCNitro]

facing.PNG

You are right, but if you play with the options in facing you can make it pretty much act the same way as the first one. I get what people are saying about it adding up over hundreds or thousands of parts, but I think you can get the face to perform very well if you just play with options.

I use to let it 'default' to leaving the part completely at the end of stroke, but unless you are trying to achieve something special with the finish there is no need. As long as the radius of the cutter machines the very far corners it does not have to completely leave the part if you use the high speed loops option. I don't think there is anything wrong with drawing your own lines and programming a contour to face with, I just don't see it as necessary for the most part. A very long time ago (maybe X2 or X3) a guy said this same thing "the facing doesn't work right so i draw my own lines", I just called BS on that. It will do what you want if you play with options. Yes, if you are trying to shave 1-2-3 seconds off each part, ya maybe with your own lines and using contour you can do that. Fortunately for me I am not in that position! 

Granted that I probably have never taken the time to really learn the Facing toolpath, perhaps if I gave it a chance I'd make it work like I want, but why waste the time when I can do what I need faster my way.(probably the wrong logic, but if it works for me...The only Facing option I really like is the dynamic, sometimes it gives me a really nice finish, specially when its a large round part.

 

No, I think we might have had the same boss at one time! HAHA. Seriously though, sometimes it is faster to let the machine/cam/programmer do their thing and get the part cutting instead of tweaking every single feature to save a minute here and there. Yes, you get in production then you start looking for those time savings, but for 1-2-50 parts it often does not offer any payback (unless you really have the programming dorked up!).

If you worked in Ventura county, perhaps.  Agreed, but you and I get that, he didnt...

[guitar]

I didn't quite understand the question.

 

Guitar:   2" facemill that stays in the cut while using the standard Facing without extra geometry

 

FACING.JPG

 

 

Yes, that is good. And, we are assuming that he is facing simple geometry in this case. If you get any more complex than a simple rectangle, MC facing always seems to fail. Then you need to start playing around with pocketing because the MC facing paths are severely limited and start demanding 50% tool overhang. One thing that really frustrates me is the inability to specify F/S and stepover over rides for the finish pass. So, your facing almost always ends up being 2 ops.

[Rstewart]

 

Those that see the forest choose NX. That that can only see 1 tree choose MC.

 

 

I wish you would venture into that forest and and Fall Out of this "tree"

 

Never Heard so much dang Complaining

[guitar]

I wish you would venture into that forest and and Fall Out of this "tree"

 

Never Heard so much dang Complaining

 

 

Please elaborate on how perfect the MC facing routine is. Maybe, after 10 years of using it, I am unaware of the proper use.

[Guest]

Here's the difference...

 

In Mastercam, the 2D facing routine is base on a flat 2D boundary...it makes no exception for stock......

 

If you want to program for an accurate to a stock blank, you can use any one of a number of surface paths and use a CAD model of your stock and your path will respect your stock model.

 

It's all in how you use it..but mostly, know HOW to use it

[Newbeeee™]

Yes, that is good. And, we are assuming that he is facing simple geometry in this case. If you get any more complex than a simple rectangle, MC facing always seems to fail. Then you need to start playing around with pocketing because the MC facing paths are severely limited and start demanding 50% tool overhang. One thing that really frustrates me is the inability to specify F/S and stepover over rides for the finish pass. So, your facing almost always ends up being 2 ops.

I agree with you ref the speed and feed override for final cut. We need this implemented and there is an enhancement request in the system. Rough fast, finish slow.

The more that ask for it, the more likely this will hopefully get implemented.

 

As for the rest of the gripe, I've never had a problem. As shown above by RStewart, you can adjust as required to get zero air cut for square/rect stock. Easy peasy lemon squeezy.

For anything else where cycle time is that important, draw the centre line and contour with compensation off. You then get exactly what you want so you only have yourself to blame.

Or install x+ (or is it verisurf) addon, where you can draw your own path by specifying the tool diameter first.

 

BTW  - you obviously haven't got another job or bought your own copy of NX yet then?

[MIL-TFP-41]

.........

[Müřlıń®]

The facing Function is a down and dirty lightning fast tool path for drawing a window around your part and flattening it out...... simple easy cheezy....

 

If you are doing 1000's of parts, you obviously do not want to use the facing tool path as is, its a no brainer to me.

 

But what you CAN do with the facing tool path on parts where you want to shave every sec off,  is to help create the geometry needed for your tool path with very little effort.

 

Just do a tool path, save as geometry, then just make some minor edits and you have what you need, run a contour with CC off....quickly, efficiently....easy peezy....

[guitar]

Realistically, you don't need to create geometry if you use the pocket ops. Just select the solid face (and maybe an entry point) and you are good to go. 

You guys are right. The facing op is simple. I just think it is too simple. Below is a picture of a VERY simple part that MC completely bombs on.