dressup minor issues

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JoshM
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dressup minor issues

Postby JoshM » Tue Apr 03, 2018 5:46 pm

I just ran an aluminum job and used Ramp dress-up on it. One thing that I noticed that surprised me was that the Ramp-Angle is specified relative to the Tool, not the Job, and so if I want to specify a Steep Ramp, I approach 0-Deg, and for a Shallow Ramp, I approach 90-Deg. This seems counter-intuitive to me.

I also mistakenly started to use a LeadInOut instead of a RampEntry dressup, and noticed it has a mispelled parameter: "Mashine CRC"

Best,
Josh
chrisb
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Re: dressup minor issues

Postby chrisb » Tue Apr 03, 2018 8:03 pm

JoshM wrote:
Tue Apr 03, 2018 5:46 pm
One thing that I noticed that surprised me was that the Ramp-Angle is specified relative to the Tool, not the Job, and so if I want to specify a Steep Ramp, I approach 0-Deg, and for a Shallow Ramp, I approach 90-Deg. This seems counter-intuitive to me.
Is there a common way to define the ramp entry angle among different tool suppliers? Then Path should use it in the same way.
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JoshM
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Re: dressup minor issues

Postby JoshM » Wed Apr 04, 2018 3:00 am

I’m not sure. I picked up my bias from previous software, but it seemed counter-intuitive to me that 0-degrees should be the steepest ramp entry angle.
herbk
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Re: dressup minor issues

Postby herbk » Wed Apr 04, 2018 5:29 am

Hi Chris,
chrisb wrote:
Tue Apr 03, 2018 8:03 pm
Is there a common way to define the ramp entry angle among different tool suppliers?
[/quote]

I don't understand the question... What dos have the tool supplier to do with the ramp entry?
Gruß Herbert
chrisb
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Re: dressup minor issues

Postby chrisb » Wed Apr 04, 2018 5:38 am

JoshM wrote:
Wed Apr 04, 2018 3:00 am
I picked up my bias from previous software, but it seemed counter-intuitive to me that 0-degrees should be the steepest ramp entry angle.
I could argue that straight down is what you really want, so 0° is no deviation from the target. Let's see what the experts say.
You need at least FreeCAD 0.19.23300 to edit my current sketches.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
herbk
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Re: dressup minor issues

Postby herbk » Wed Apr 04, 2018 5:56 am

Here a link which show's and explanes it very detailed:
https://www.sandvik.coromant.com/en-gb/ ... Country=gb
Gruß Herbert
chrisb
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Re: dressup minor issues

Postby chrisb » Wed Apr 04, 2018 6:09 am

In an older forum post about ramping I found this link http://shop.lmt-tools.de/media/import/l ... lungen.pdf which supports your view: 0° means no ramping at all, 90° means going straight into the material.
You need at least FreeCAD 0.19.23300 to edit my current sketches.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
chrisb
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Re: dressup minor issues

Postby chrisb » Wed Apr 04, 2018 7:44 am

Same with Coromant tools: https://www.sandvik.coromant.com/_layou ... 7&lt=false page I17, parameter RMPX.
There is another interesting general document from Coromant: Training Handbook - Metal Cutting Technology
You need at least FreeCAD 0.19.23300 to edit my current sketches.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
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bill
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Re: dressup minor issues

Postby bill » Wed Apr 04, 2018 5:37 pm

This is a MAJOR minor issue.
JoshM wrote:
Tue Apr 03, 2018 5:46 pm
to specify a Steep Ramp, I approach 0-Deg, and for a Shallow Ramp, I approach 90-Deg. This seems counter-intuitive to me.
The RAMP, which is defined as an angle (alpha degrees - also commonly called the angle-of-attack) is chosen not to exceed the end-mill (tool) concave/dish/cutting edge profile; or whatever one calls this tool feature. This applies to dead-center tools (not cutting edge on center axis) which are most common.
from Sandvik:
alpha-angleofattack.jpg
alpha-angleofattack.jpg (11.26 KiB) Viewed 636 times
This is why TABs Dress-Up is not as simple as one would believe. The approach to a tab is trivial-path, whereas exitting a tab is a little more complex and should be inversely-similar to the picture above.
polymer
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Re: dressup minor issues

Postby polymer » Wed Apr 04, 2018 7:55 pm

The Tool-Library definitely needs two extra options: ramp angle and min. diameter for helical ramping.

Both depends from the geometry of the tool.