Contour with wear

[P_Scott]

Iskander,

 

I also don't want to argue. My point was to share some reasons for why users choose Wear compensation instead of Control. I am an ex-programmer/setup/operator. I was always taught to use Wear comp except in situations where comp is not practical, such as engraving with single line entities (text and part numbers). I am not trying to force my opinion on anyone here. My original reply was to show that there are some excellent reasons for using Wear comp. Just as in your original reply to Harry's question you supplied excellent reasons for using Control comp.

 

The point is everyone's different and my thoughts were to allow Harry to make up his own mind about CC in Mastercam from having all the available information. Iskander, one statement you made doesn't make any sense to me.

quote:

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If you mill a very accurate spline built from a huge ammount of points and you can not filter it due to CC wear it also doesn`t matters noone ?!?

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Why can't you filter the linear moves in the toolpath? Filtering a large toolpath, especially one that was generated from spline or surface data, seems to be a necessity to me. Filtering replaces thousands of tiny linear (G1) moves with much fewer arc moves (G2 or G3).

 

I did a test in Mastercam. I created an Ellipse. It is a spline entity. I contoured this ellipse and posted the code first with control comp and no filter. The result was 104 lines of code. I then posted the same contour after turning Filter on. I got 96 lines of code. Then I tried Wear on the exact same toolpath. With Filter off I got 102 lines of code. With Filter on I got 51 lines of code. If what you say is true, why then is filter working with Wear CC? I think there seems to be a little miscommunication going on here.

 

Filtering works regardless of CC settings. In fact, it seems to filter better WITH wear CC instead of control CC. The results speak for themselves. The majority of the toolpath using Wear CC and Filter is G3. The majority of the toolpath with Control CC and Filter is G1. If your limited by memory in an old control, why wouldn't you use Wear and Filter?

 

I just want Harry to understand that he has a choice to make and I'm trying to make that the best informed choice he can possibly make. That's what we're all here for. To help new users out. If he decides to go with one type of CC instead of another, that's OK. Just as long as he understands the differences between them and makes an informed decision for his situation.

 

I don't mean to argue with you Iskander and Eeyore, or anyone else in this forum. As a lad, Tigger was my favorite "Pooh" character but in truth I liked them all. This is not a personal disagreement. It is simply a difference of professional opinions. I have a lot of respect for you Iskander, even though we've never met. Your posting in this forum shows the character of your personality. All I wanted was to show the differences and allow Harry to make his decision based on the knowledge presented here, from both sides of this "old argument". To ALL. I hope this helped you Harry. Once again I apologize for the long post.

[Eeyore-nonhuman forum member]

Hello Peter and everyone else ,my friends !

 

I made a little test program

ftp://mastercam:[email protected]/Ma...iles/EETEST.ZIP

it`s clearly seen that in inner motion wins wear with filtering but all the results close one to the another yet in outside motion wear looses with result 200%.

Code twice bigger .

Peter I bet U checked the inner contour ?!?

Ready to explain why this happends .

 

I also thank you for your will to understand my and Wol point of view.

We both do prefer control but are ready to work with any type U wish or without any at all .

 

In futuro I `ll try not to be so obstinate

[P_Scott]

Eeyore,

 

I just did the same toolpath operation just reversed the chain direction and changed side so it would be on the outside of the profile. True the Control CC with Filter does actually produce less code on the outside. Untrue is your statement that Wear CC with Filter on the outside actually doubles the code. It doesn't. It produces only 1 more line of code than the toolpath that was Control CC with Filter. At least on my ellipse file. Perhaps the Filter settings, such as tolerance and look ahead, are not the same on your test as in mine. I will try it out on your file. This is a very interesting discussion. Let's continue it in a reasonable manner.

[Fig sign]

Peter !

Let`s discuss . That`s interesting .

We are not arguing we are simply trying to explain facts.

Show me your file ,please !

Have you seen Eeyore`s file ?

[Nominal]

You guys are wearing this one out.

The beauty of this whole thread is that everybody can do this however it works best for them. I'm just glad MC is robust enough to offer more than one way. I doubt any one of us can convince anyone else that one way is better than another. Especially old timers like us.

[MACHINEMASTERG]

15 years ago were i used to work they had cc in the machine but insted that we trig that tool around the part and comp the tool ourselfs in our mind because that cutter comp DOSNT DO IT RIGHT (said in a loud german accented voice) it sucked when the tool broke and the new one wasnt the same size ...any way its all good now matter how you doit in mastercam good parts is all that matters remember its friday not to much thinking aloud

[P_Scott]

Iskander and Eeyore,

 

I tried out Eeyore's file and it does seem to double the output with Wear CC. Here's the really interesting part. It doesn't reduce the amount of code whether Filter is on or not. It'll do it for Control CC. I tried adjusting some of the Filter settings to reflect more of what I would normally do. I doubled the Filter tolerance from the Linearization tolerance and increased the look ahead to 10X more entities. I also shut off the "one-way filter" switch because I wanted to see if that had any effect. I usually filter both ways and create as many arcs as possible. Whatever I tried didn't seem to have any affect. The result was a larger toolpath than with Control comp. That was on the outside. On the inside it made a huge difference. I'm not sure why it didn't give me the same result on my ellipse. It might have something to do with the units of measure. Eeyore's ellipse is metric while my original test ellipse is in inch units. This one stumps me. It still doesn't mean that the filter isn't working with Wear CC, just that it works much better with inner contours than outer. Go figure. I'll have to look into this in more depth later on. Good puzzle Eeyore.

[Eeyore-nonhuman forum member]

Peter !

I can explain properly everything but only later !It is time to sleep now for children and donkeys

If you want a guess just draw a rectangle and create /xform/offset contour and make some inner and outer offsets and think

You `ll catch it quick yourself

 

The world is full of xxxx things

[P_Scott]

Eeyore and Iskander and All,

 

I figured out why Wear CC with Filter wasn't working as well on the outside of the contour instead of inside. It's due to the "Roll cutter around corners" switch again. When the contour is done to the outside on a spline, Mastercam automatically breaks the spline into tiny linear (G1) moves. It then proceeds to roll the cutter around all the "corners" between the lines. This produces an arc (G2 or G3) between the lines and then the code is attempted to be filtered. Because the filter is only designed to replace linear moves, not a combination of line, arc, line, arc, it interprets the code to be filtered already. If "roll cutter" is not turned on (None position), the resulting code is broken down into linear moves without small arcs between the lines. This then can be filtered correctly and reduces the code for an outside contour with Wear comp. The amount of lines (blocks of code) is the same as a toolpath with Control CC and Filter turned on. So if you want to use Wear CC on the outside contour of a spline and you want to reduce the size of your NC file, make sure "roll cutter" switch is selected to "None". Oh, and the Filter tolerance should be about double the Linearization tolerance. Now that we've completely beat this horse to death and hijacked Harry's thread. Sorry about that Harry. Are you still there? Harry?

 

[ 01-23-2004, 04:20 PM: Message edited by: Peter Scott ]

[Nominal]

quote:

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we've completely beat this horse to death

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Ya think?

[Eeyore-nonhuman forum member]

To Peter And All !

 

Setting roll over corners to sharp and none is dangerous and can lead to scrapping and leads to burrs !

And to set it with CC wear or computer (that basically is the same )to sharp and none also is unfair comparessment ,don`t forget that the goal is not only to get good filtering results ,but also good parts .

 

Peter !

Can you explain why it is so?!?

Can you give some examples ?

 

Bravo Peter !

 

quote:

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Because the filter is only designed to replace linear moves, not a combination of line, arc, line, arc, it interprets the code to be filtered already.

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That`s close to truth ,IMHO!

You are getting consistent tangental toolpath

And Mastercam is checking toolpath for tangency.

That`s was covered here

IOW if the toolpath will consist of arcs,splines and lines nontangent it will be filtered !

dirty tricks

 

Peter !

If you want not to offend people start the new thread and we `ll discuss this interesting matters there

 

EEyOOre spammer and hijaker

 

[ 01-23-2004, 10:16 PM: Message edited by: Eeyore ]

[Guest CNC Apps Guy 1]

I ALWAYS have my contours set to roll cutter around ALL corners. It leaves those corners sharp enough to slice you good if you're not careful and that's plenty sharp in my book. So what if it's more code. I don't want folks editing my code.

 

JM2C

[crazy^millman]

I have not had a problem yet and I find the machine runs smoother when it is doing this verse when it is not. I understand what is neing said but I think it really depends on the machine, material, part geomentry, and other things and apply what works best for each application.

 

Crazy Millman

[Eeyore-nonhuman forum member]

Hi,folks !

I am running to the Iskander`s daugter bat-mitzva

so can drop only a couple of words

 

Draw a V-shaped lines and build xformoffset contour left 10 mm all corners

Now make toolpath contour with em10 CCwear or computer and Roll over none and enjoy HUUUGGGE

scrapping overcut.

the same for sharp for angles greater then 135 degrees (overcut will be less anyway)

I will supply a bunch of examples when i will be back if I`ll be sobber enough !

 

 

Eeyore (in a drank voice ):Gibb me tThHisStTlLes ...