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Divide Face & Draft
- Thread starter PHayden
- Start date
JohnRBaker
Mechanical
Can you post the part itself?
John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
- Thread starter
- #3
JohnRBaker
Mechanical
OK, look at this model. I used the Draft function but selected the Type option 'To Parting Edges', which will allow you to select multiple edges and apply multiple Draft angles.
I've attached both a file an AVI showing the way the function is used (note that the AVI shows NX 6, but that's only because NX 6 has a built-in AVI capture, but the Draft feature work-flow is the same as what I did in NX 5).
John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
I've attached both a file an AVI showing the way the function is used (note that the AVI shows NX 6, but that's only because NX 6 has a built-in AVI capture, but the Draft feature work-flow is the same as what I did in NX 5).
John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA
To an Engineer, the glass is twice as big as it needs to be.
- Thread starter
- #5
You have to draft from the edges of a divided continuous face which is appropriate since the split usually defines a parting line in a tool. Sometimes if the angle is over 45 degrees it tends to get the wrong side and there is no way to force it to apply to one face or the other. For those rare occasions the only way I have found in to apply a small draft first and a larger one after the break has been made. You'll get two features where you wanted one, but a better idea has eluded us thus far so we name or group the the pair make it more obvious what has occurred.
Cheers
Hudson
Cheers
Hudson
PHayden:
After you split the face and begin the draft workflow, when you select the face to draft, make sure the selection filter is *not* set to tangent faces, but rather 'single face'. If you do this, the draft will only be created on one side of the split.
I think what may be happening is that the system recognizes both sides of the split as being tangent, so it selects them both.
Ed
After you split the face and begin the draft workflow, when you select the face to draft, make sure the selection filter is *not* set to tangent faces, but rather 'single face'. If you do this, the draft will only be created on one side of the split.
I think what may be happening is that the system recognizes both sides of the split as being tangent, so it selects them both.
Ed
Here's what I was talking about... if you're drafting to a parting plane, the tangent selection picks both sides of the divided face.
While we're on the topic, how do you handle stepped parting lines? I'm interested in a possible better approach to what I've been doing, which is to sketch a stepped curve on the face to be drafted, then creating a parting plane thru one of the edges and drafting to that partign plane.
While we're on the topic, how do you handle stepped parting lines? I'm interested in a possible better approach to what I've been doing, which is to sketch a stepped curve on the face to be drafted, then creating a parting plane thru one of the edges and drafting to that partign plane.
There are two types of draft one is called draft and the other is called draft body.
To use draft body you don't need to divide the faces and for cases that it is suited to it certainly works as advertised. It works by adding material onto the parting line and holding the shape at the top and/or bottom profiles. If you want to learn about it start with a simple block as your example and use the documentation to get an idea about how it works.
When drafting to a parting plane most molded parts that I have dealt with in industry are designed to hold their shape at the parting line and taper material by removing it from the sides of the solid above and below that line. The techniques described for using the other Draft function work with that perfectly well, but it will not divide the faces for you.
The other thing you write about that may occur when you refer to drafting to a parting plane, is that provided you use essentially the same plane to draft to and divide the faces I'm guessing that you simplify the selection process and make things easier. If that guess is similar to the cases you're referring to then by all means I see no harm in continuing to use it, but in terms of describing a method that can be used in all cases I didn't refer to it this as it may just be a common coincidence. The result in cases of stepped parting lines is mismatched unlike anything I'd ever want to use and it doesn't save me any clicks in applying it.
For your stepped parting line again I think that the main problem that I can see right off is that your the steps are too vertical such that the geometry through the stepped section has no shut face for the draft to work with. You may be getting errors. So I attached an image with 10 degrees draft along the Z+ and Z- axis on either side of a stepped parting line. You can see the resulting faces red and green above and below the parting line that used sketch curves on the side of a 100mm square block. The sequence was block, sketch, divide face, draft, draft. You have to apply the two drafts in different directions separately.
Cheers
Hudson
To use draft body you don't need to divide the faces and for cases that it is suited to it certainly works as advertised. It works by adding material onto the parting line and holding the shape at the top and/or bottom profiles. If you want to learn about it start with a simple block as your example and use the documentation to get an idea about how it works.
When drafting to a parting plane most molded parts that I have dealt with in industry are designed to hold their shape at the parting line and taper material by removing it from the sides of the solid above and below that line. The techniques described for using the other Draft function work with that perfectly well, but it will not divide the faces for you.
The other thing you write about that may occur when you refer to drafting to a parting plane, is that provided you use essentially the same plane to draft to and divide the faces I'm guessing that you simplify the selection process and make things easier. If that guess is similar to the cases you're referring to then by all means I see no harm in continuing to use it, but in terms of describing a method that can be used in all cases I didn't refer to it this as it may just be a common coincidence. The result in cases of stepped parting lines is mismatched unlike anything I'd ever want to use and it doesn't save me any clicks in applying it.
For your stepped parting line again I think that the main problem that I can see right off is that your the steps are too vertical such that the geometry through the stepped section has no shut face for the draft to work with. You may be getting errors. So I attached an image with 10 degrees draft along the Z+ and Z- axis on either side of a stepped parting line. You can see the resulting faces red and green above and below the parting line that used sketch curves on the side of a 100mm square block. The sequence was block, sketch, divide face, draft, draft. You have to apply the two drafts in different directions separately.
Cheers
Hudson
- Thread starter
- #11
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