Creating a new "start part" 1

[walkersea]

I'm very new to NX3, and need to know if what I am about to propose is a good method or not.

If I create a "start part" for our usual components - e.g. a model that contains the correct datum planes, attributes, etc and then also have the drafting sheet set up with the company border, and populated with the attributes from the model. I'll store this in a read only area and then whenever a new part is created, the "start part" file is opened and saved as the correct part number.

There will only be three users initially, so no PDM system. There is a standardised system for the part numbers, and the model and detail drawing have the same part number. We don't do large assemblies, so I can't see disadvantages of doing it this way.

Anyone out there got any comments? I've seen a few threads relating to GRIP - no idea if this means I'll have to learn to program or not.

Regards.

 

[Shadowspawn]

Abeschneider,
Tis one of those things that sounds more complicated than it really is and is kinda tuff to explain, but here goes...
In your assembly, the piece part is 'out in space' someplace, positioned where you want it. It is a certain distance and orientation away from the absolute csys of the assembly (say for example, x=30,y=23.3245,z=126.4293847474 or whatever). In your piece part, place a csys at the negative values (x=-30,y=-23.3245,z=-126.429387474) and save it as the 'Eng CSYS' or whatever. Add this saved csys to the reference set that you use to place the piece part in the assembly.
Now, when you add your piece part to the assembly, you can use this csys to easily place the part (especially when your not mating...). Unfortunately, this little method doesn't work for parasolids. The work around for this that I usually use is to create 3 really skinny cylinders to represent the csys and export this out with the parasolid. Once the parasolid is brought back into UG, you have a fairly easy method to reposition the parasolid where you want.
Clear as mud? Make any sense?

SS

 

[abeschneider]

SS
Yeah it makes sense. Just curious - what precision would you need to specify the location? ("z=-126.429387474 ... )

 

[Shadowspawn]

Abe,
Realistically the precision doesn't need to be that exact obviously, but we do (as a rule) use whatever coordinates are given to us by our customers (engine manufactures and airframers). Just a case of using what our customers give us for the most part...

SS

 

[HellBent]

I've gone as far away from drawings as possible. Several of my former employers call out the drawing as the "master"....that's so 80's! The problem with this is...when a change needs to be made....lazy designers go in and edit a dimension or tolerance on the drawing rather than tweak the 3d. This leads to countless issues when the tools are built from the data. Contrary to popular belief....tool shops do NOT verify the 3d to the drawing. In some cases critical features will be tweaked but we (the tool shop) don't get paid or get time to re-design your parts. Regardless of what the PO's say...that's the real world.

On a lot of product work I do now I create a simple drawing with nothing more than reference views and maybe a few critical dimensions or tolerances. Then the almighty note: "3D MODEL IS MASTER, REFERENCE 3D MODEL FOR UNSPECIFIED DIMENSIONS". I then supply my customer with native data, a parasolid file, and an IGES file. All of the cheap viewers have translators for all of the major packages and I've found it very easy to talk my customers who don't have CAD to purchase a viewer such as Spinfire or Autovue in which they can section, dimension, analyze volumes, etc. As embedded GD&T evolves the drawings will eventually go bye-bye. The 2d drawing that people may currently reference will simply be replaced by a 3d model. Right now .jt is the only neutral format that has 3d GD&T support...but that standard is still pretty new.

Take care...

 

[MSPBenson]

One down side to a CSYS.
Sometimes the datum axis in a csys is not recognized.
An input that requires a datum axis will often not let you pick a csys so I tend not to use them anymore.
I ended up having to create seperate Datum axis for positioning dims and reference directions.

Mark Benson
CAD Support Engineer

 

[Shadowspawn]

Mark,
I've experienced what your describing on a few occassions while dimensioning a sketch. The simple fix for me was to change my dimensional constraint type from an explicite 'horizontal' or 'verticle' type dimension to an the 'inferred' dimension, and pick the axis first.
If you've experienced this outside of sketcher, I'd like to hear more...

SS

 

[MSPBenson]

SS,

I've just been trying to use it and break it.
No success so far.
I think the las time I used it was in NX and it treated it as 1 object when you seected it.
I've noticed in NX3 as you select it it actually recognizes each part of the csys as a seperate axis or plane. The problem used to be something would want a datum axis and when you selected the csys it selected the whole thing not just the axis and wouldn't accept this as an input.
I'll start using it again now and see if I can find any cases where it doesn't act the same as seperate features.



Mark Benson
CAD Support Engineer

 

[abeschneider]

I routinely use the separate components of the CSYS feature as reference planes or axes in NX3.