Instancing an edge blend in NX8.5

[bb1982]

Good afternoon to all users,

I'm trying to instance an edge blend using an existing feature pattern as a reference in NX8.5: I've tried all sort of settings but I couldn't get my blend properly patterned! Furthermore, I get a warning message ("Edge blend cannot be patterned without its body patterns") immediately after the selection of the feature to be instanced.
As a final note, the blend is applied on a patterned boolean feature (subtract).
Thanks everybody in advance and...I really miss my "blend all instances" feature!

 

[Xwheelguy]

Without seeing your model, it might be a bit difficult to offer suggestions. Off the top of my head, I'd have to ask if you can apply the Blend immediately after the Subtract and include the Blend in the Pattern with the Subtract?

I tested the above on a very simple model in NX8 and got an error message saying that I needed to change the Pattern Method to Variational in order to include the Blend. Once I did that, the Pattern worked fine for me. As I stated, though, someone will probably need to have a better idea of the model and workflow being used to offer a working suggestion.

Tim Flater
NX Designer
NX 8.0.3.4
Win7 Pro x64 SP1
Intel Xeon 2.53 GHz 6GB RAM
NVIDIA Quadro 4000 2GB

 

[bb1982]

Hello users,

I've uploaded a simple test file which explains the problem I'm currently having with instancing of edge blends.

Thanks for your kind hints

 

[SvenBom]

I have made some changes to your part. First of all, the subtract option was selected in revolve command. Because of that, I could delete subtract feature from part navigator. Then removed your patterns and create new one.
Remember, that Blend is now created with Pattern command. It is not as in previous versions, where you have placed a blend on already created instanced feature (with using 'blend all instances').

I have uploaded my model, so that you can see, what I have done.

 

[bb1982]

Thank you very much for your suggestion.
Nevertheless, my goal was not to simply have slots and blends, rather to find the correct way to link a new instance (blend) to an existing one (subtract).

 

[SvenBom]

I have just placed Blend after the subtract and before pattern. Then, I have edited your pattern so, that I have include also edge blend and revolve(2) features.
The error message in pattern command also describes, that if you select just edge blend, it is not enough. You have to select also the parent feature.

And your fixed model is attached.

 

[bb1982]

Again thank you

Is there any way to get same result with two instances, where the second refers to the first one?(I'd like to understand how the layout option "Refernce" under "Pattern definition" works)

 

[carlharr]

I've just been having a go with this, as we are just about to move to 8.5.

I changed the "slots" to "wings" for easier viewing.
Then added two blends...
pink applies to the instanced "wing" only
blue applies to both the instanced "wing" and the original revolved.

Although both patterns initially complained that parent objects were required, once I'd selected reference pattern, and the correct instance handle for first feature, they've both worked fine.

Yes I could have moved the blends before the original pattern and included them, but I think reference is working ok.

I'll try again on the OP model.

http://www.jcb.com

NX 8.5 with TC 8.3

 

[bb1982]

So it looks like the boolean is the problem...I'm really never in the lucky condition of being able to embed the boolean directly in a revolve/extrude or whatsoever.

I do have generally a "complex" body to unite/subtract plus some additional feature (like blends) to add later on

 

[carlharr]

Yes it does seem to be a problem with the boolean.

Reference pattern does't work at all if the original boolean is a separate feature - I've tested both with your version and with mine.

http://www.jcb.com

NX 8.5 with TC 8.3

 

[bb1982]

Thanks carlharr

it's a real pity in my opinion that instanced boolean is no longer available as well as the "blend all instances feature"...

 

[carlharr]

Well to be fair, blend all instances is almost defunkt, because the blends can now be included in the original pattern.

That said, there are times when you can't include the blend till afterwards, and blend all instances was pretty straightforward!

http://www.jcb.com

NX 8.5 with TC 8.3

 

[Xwheelguy]

I'm on NX8 and can't open any files (pics are worth a 1000 words sometimes). Can you not model this part in a wedge (like a slice of a pie) then pattern or instance (i.e. Instance Geometry) the resulting solid around and unite them all together? Sometimes getting the workflow you want for a few areas will result in changing the whole approach slightly.

Something that might still be around is Group Feature (just checked and it's Format -> Group -> Feature Group). The workflow is something like this:

1. create the features you want to be patterned first (booleans can be included or excluded with features I THINK).
2. create the feature group and add the features you wish to be in the named group (add Booleans if they are separate from their parent features)
3. instance the feature group.

I used to design OEM and aftermarket aluminum wheels and while the patterning or instancing of blends was at times a challenge, we were always able to come up with a workflow that would give us what we wanted. Did I always end up modeling a part the way I wanted or anticipated? No, I did have to change my approach at times. I will have to say that Blend All Instances option was nice but it didn't always work, depending on the situation.

Tim Flater
NX Designer
NX 8.0.3.4
Win7 Pro x64 SP1
Intel Xeon 2.53 GHz 6GB RAM
NVIDIA Quadro 4000 2GB

 

[carlharr]

Hi Tim,

Might model the alloys off my car later that would be a good challenge for patterning, thanks for the idea!

Attached an image of the OP's part, which is a solid revolve, followed by a slot which is revolved, subtracted and then patterned.

So, I just created a feature group with the slot revolve and the subtract inside, which I then patterned (by selecting the feature group itself).

I then added the blend, and attempted to reference pattern it, but it still failed.

The reference only seems to work if the original subtraction is inside the revolve feature - unless I've done the feature grouping wrong?

http://www.jcb.com

NX 8.5 with TC 8.3

 

[Xwheelguy]

Hello carl,

If I recall correctly, Booleans outside their parents must be included in the Feature Group (else they won't be Instanced/Patterned). Blends may or may not work using that workflow, it was hit and miss and I was never able to figure out why that was such.

However, once Instance Geometry hit the toolbars, I was set - I'd just model a "slice" and then when completed Instance the solid body and Unite all the pieces into one solid. Didn't need to worry about the pattern of anything changing, as those things were decided long before I got my hands on the math.

Tim Flater
NX Designer
NX 8.0.3.4
Win7 Pro x64 SP1
Intel Xeon 2.53 GHz 6GB RAM
NVIDIA Quadro 4000 2GB

 

[carlharr]

Hi Tim, the attachment didn't work I will try again (as you say, a picture speaks a thousand words).

In the part I created a feature group which contained the revolved slot, and the following subtract boolean.
I then patterned the feature group.
Finally I tried to reference that pattern for the blend, which failed.

So it looks like feature group might not work this time.

http://www.jcb.com

NX 8.5 with TC 8.3

 

[carlharr]

Here's the other one I'd struggled with.

A "slice" type model with a blend required between the slices, and again reference pattern doesn't work.
Possibly because of the unite, but there's no way to change that here.

Someone suggested including half the blend each side in the sketch, which did work although not "elegant".

Interestingly, in NX7.5 "array" does the unite as part of the command, which I didn't realise.
And then "blend all instances" worked just fine.

Still, there's always a way - maybe I should have just used pattern in my sketch!

http://www.jcb.com

NX 8.5 with TC 8.3

 

[Xwheelguy]

Carl,

I still prefer Instance Geometry to the Pattern Feature command as I'm messing around with Pattern Feature a little more. Definitely doesn't care for some Booleans. Even had it give me an error message, I went in and changed some settings (before hitting OK or Apply), then changed them back and the error message disappeared and it did everything it originally said it couldn't (see the movie).

I feel that the Pattern Feature may behave better with the Booleans embedded with the parent features (Revolve, Extrude, Sweep, etc.) when possible. The reason I say this is because other than when performing Booleans between associative bodies (like after a Mirror then Unite), the Booleans can now be changed within the parent, so there isn't a really good reason to keep them external from their parents anymore (in my opinion).

Hopefully all attachments will work.

Pattern_NX8.zip

pattern_movie_NX8.zip

Tim Flater
NX Designer
NX 8.0.3.4
Win7 Pro x64 SP1
Intel Xeon 2.53 GHz 6GB RAM
NVIDIA Quadro 4000 2GB

 

[JohnRBaker]

In the cases where you can't use Pattern Feature, have you looked at using Pattern Face? Note that while Pattern Face is currently included with the Synchronous Modeling set of functions, it's being updated with NX 9.0 and at that point, between Pattern Feature and this New updated Pattern Face function, we think we've covered most all possible situations.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[Xwheelguy]

John,

Did you see the .avi and the behavior of which I was speaking regarding the warning/error message appearing then disappearing after settings are changed then changed back to default? Does it still do this in newer versions of NX?

Tim Flater
NX Designer
NX 8.0.3.4
Win7 Pro x64 SP1
Intel Xeon 2.53 GHz 6GB RAM
NVIDIA Quadro 4000 2GB