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Non Sketcher users
2

Non Sketcher users

Non Sketcher users

(OP)
Are there many of you who don't use sketcher?
Most models in our company don't use and we seem to model just fine using basic curves.
Just wondering

John D

RE: Non Sketcher users

I never used sketcher until about 6 months ago, when I finally took a UGX class and learned how to use it.  I use sketcher almost exclusively now for making the basic parts, and find using curves a much slower way to model.  I would recommend at least giving sketcher a shot, it is addicting!

Reidh

RE: Non Sketcher users

(OP)
Thanks, I hope this thread gets a lot of replies.
I intend on getting good at Sketcher for no other reason than to make myself more marketable.
Whether or not there is really any value added is another story I think. Every Company's needs are different.

RE: Non Sketcher users


Has anyone ever shown what sketcher can do? Have you ever done a side by side comparison?

2d curves vs Sketcher.

Disadvantages of modelling using 2d curves (Basic curves)

1. If end points do not lie coincident (on top of each other) there is no way of knowing until your extrusion fails. (sketcher will display a symbol)

2. Changing a profile involves calculations and triming of curves. (Sketcher will keep lines trimed based on geometric constraints- coincident, midpoint, tangent)

3. Curves could snap to a surface off of the X-Y Plane. (Sketches will stay only to the sketch plane)

4. Curves will not update when associated to other curves of a model. (Sketch curves can keep midpoint relationships for example making edits quick and models symmetrical.

5. Curves cannot be mirrored associatively and dimensioned  as a diameter. This forces a user to find the radius of every diameter. (Sketch is mirrored over center line, mirrored geometry is made reference and dimensions are applied as a diameter.

6. Curves have to be grouped to be selected as one. (Sketches can be selected as one feature and moved to a layer.)

7. Curves can sometimes be left unrounded (34.53234493) causing model edits when drafting. (When sketches are dimensioned, dimensions that are not rounded are clearly visible and can also be fully inherited into a drawing view reducing drafting hours in some cases)

8. Trimming functions for curves are slow and involve multiple selections. (Sketcher trims can be quickly "drawn over" using quick trim saving time)

9. Curves cannot be made equal to any other curve. (sketches can have multiple circles all equal the same diameter easily. Equal radius geometric constraint).

10. Curves have to be transformed to be moved. (Sketch curves can be dragged and the model updated quickly. This has great advantages when modeling in the context of a large assembly)

11. Curves could be drawn at a angle. (Sketch curves can be visually set to horizontal or vertical to the horizontal reference)

And lastly, using curves can be faster then sketching if your staff does not understand how to use sketcher properly.

Every sketch you fully constrain makes you a better sketcher and you will find in industry that anyone who dislikes sketcher typically does not know how to use it very well.  This is the main reason for it not being adopted into designers every day modelling practice. Not using sketcher is like driving a new ferrari around and only using the first two gears.  Your missing out on alot of NX's functionality.

Peter
 

RE: Non Sketcher users

I think sketcher is great to make parametric models. I've used them quite a bit to automate design time down by 80% or more. It wasn't only sketcher but it had a lot to do with it.

I do use basic curves to do R&D then once the design is solidified I'll convert them to sketch if planning on making more iterations.

Lately I've been using knowledge fusion to even further my design time reduction and help with my rapid application development. But KF is a different beast and sketch isn't the best way to go for a generative based model. Essentially I build a parametric sketch in KF without using sketcher.

Unfortunately a lot of companies rely on their "experts" who  don't know sketcher so they snub it. If they only knew they could reduce design time by at least 60% with simply using sketcher, and additional savings by using WAVE and interpart expressions, this industry would be a different place.

-Dave
http://plmwiki.com
http://groups.google.com/group/NX_CAX/

RE: Non Sketcher users

I use sketcher majority of the time also.  Also trying to get the other NX designers here at my place of employment to utilize sketcher more.

Initially it may take longer to build and create, but down the road any updates are quick.

Just like Dave said, any prelim. stuff I will use basic curves and then move it to sketch after it's ok'd.

I have also started using associative curves more.  Those seem to be interesting.

Justin Ackley
Designer
jackley@gmail.com

RE: Non Sketcher users

Many times I've heard "we don't have time to use sketcher" or "it's a preliminary design, no need for sketcher".  Obviously they have not used sketcher.  Using sketcher has advantages over basic curves, but basic curves have no advantage over sketcher, in my opinion.  In both you draw lines and curves, but in sketcher you can control these lines and curves.

Even in prelminary design, which is when I hear the "we don't have time for sketcher" the most, it's very advantagous.  Ask yourself, when do you make the most changes?  on a mature part, or one that you really don't know what it looks like yet?  I can make changes on a new design very quickly using sketcher, and I can create concepts very quickly, since I don't need to know every dimension when I do it, but I can add them as I figure out what they need to be.

Once you go sketcher, you'll never go back.

-Dave
Everything should be designed as simple as possible, but not simpler.

RE: Non Sketcher users

Gunman,

I agree, simple is better. Or more specifically loosely coupled. I'm not sure what your meant by your response, I guess your assuming I don't make things simple.

Basic curves do have a benefit in initial speed. I can delete a curve, let the solid die, reconstruct, and re-associate the curves to the boolean operation by the time you initialize sketch. It is all based on your individual toolbox

-Dave
http://plmwiki.com
http://groups.google.com/group/NX_CAX/

RE: Non Sketcher users

plmexchange:  My response was just general observations I've made, not meant as a reply to your response, or to offend.  Sorry.  I should have made that clearer.  I've just heard so many times, by the inexperience sketcher user, that basic curves are faster, and I'm sure in some cases they are, ie your example, but from my experience, the sketcher has been faster the majority of the time.  

Another benefit to the sketcher, is when you're looking for the defining curves for a feature.  I can hilite the boolean, look in the creation tree, and see what sketch I need to edit.  Basic curves could be blanked, on various layers, etc.  I've spent alot of time hunting them down, to make simple changes.

-Dave
Everything should be designed as simple as possible, but not simpler.

RE: Non Sketcher users

No offense taken, just looking for clarification. You don't have to sell me on Sketcher, It has a lot of benefits. I also spend a lot of time organizing my file by putting a solid specific object on one layer and labeling if it is a large part. So each feature has all the curves, sketches, datums that it needs. No hunting around.

-Dave
http://plmwiki.com
http://groups.google.com/group/NX_CAX/

RE: Non Sketcher users

I use sketcher a great deal.  I can barely function without it.  At the same time, though, I see it used too much at times. For instance, modeling a shaft with a round head on it is much easier done with "cylinder" plus "boss".  The same goes for putting blend radii in the sketch.  Yes it helps in the layout at times, but it is harder to change from a radius to chamfer if the radius is built into the sketch.  It is indeed a powerful tool, but only when it is called for.

RE: Non Sketcher users

I also feel that it is a very powerful tool, used in a logical manner.  Some companies do take it too far though by requiring EVERY part to be built from a fully constrained sketch.  As mmauldin posts, sometimes it doesn't but you anything.

RE: Non Sketcher users

If you are already using curves for extrusions, why not take the next logical step and use smart curves?
Besides using sketcher to model individual parts, it is also very useful in other ways. For instance, I use sketches to hang datums on, then mate components to the datums. Voila, you have the ability to move your components by manipulating the sketch. Works well when when trying to determine the optimum locations of components in an assembly layout.

RE: Non Sketcher users

Hello FXjohn,

In my opinion it is the core capability what makes UG, CATIA etc. softwares high end.

It is the basic way to "mathematically define" your model to understand,  use or modify at all times not for you but also for the other UG people.

I also think sketches must be fully constrained.

PS: Thank you cyberpete for the detailed long list. Sketcher definetely worth it.

Candas Urunga
Design Engineer

RE: Non Sketcher users

What's to understand about a 1" dia primative cylinder 2" long?  It is easily editable and can still be controlled with expressions and is much simpler and quicker to create than by doing it through sketcher.
Next some people will be clamoring to do away with everything that doesn't need to be created via sketcher!

RE: Non Sketcher users

(OP)
It would be nice to see some perfect of examples of where sketcher is needed, and not needed

RE: Non Sketcher users

I model up suspension bushings and engine mounts.  Inner metal, rubber and typically an outer metal.  

I think sketcher is perfect for this because if the inner metal ever changes, I can wave link the sketches to the rubber  part file (through assemblies) and the rubber will update accordingly (assuming no drastic changes happen).

Or if the outer metal changes diameter.

And through expressions, my update time is cut tremendously.

Material savers is good, you can maintain the thickness of your walls.

There are more uses for sketcher than not, in my honest opinion.

Justin Ackley
Designer
jackley@gmail.com

RE: Non Sketcher users

I feel it all depends on the shape of the part you're modeling.  If you're making very aesthetic, freeform surfaces, then you're probably going to have a tougher time managing sketches than you would tugging and dragging spline poles outside of Sketcher, not to mention sketcher doesn't allow for any continuity beyond G1 (without some point and spline pole trickery involved in the sketch).  The continuity limit was discovered the last time I attempted using it for complex freeform surfacing, which was probably back in NX1 or NX2.  When I refer to complex freeform, I am referring to mesh surfaces, not Through Curves, Sweeps, Ruled or any type of general lofts.

If you're modeling very basic shapes with general continuity (G0 or G1), then sketcher is great and makes  perfect sense because your shapes can be very well defined in the sketch.

One technique that I've recently used with lots of success is to use Sketcher for reference curves to (more accurately) control the ending angles of Associative Studio Splines (uhhhh...no, I'm not going to use ASS as an acronym for that type of spline).  I create the reference curves, usually lines, in a sketch and assign the appropriate angles that I need, then make sure the reference lines are constrained properly.  I then exit the sketch and create the Associative Studio Spline using the endpoints of the sketch lines as the endpoints of my Studio Spline.  I then adjust the middle poles for a good curvature comb.  Should the Sketch need to change, I go back and readjust the middle poles for a similar comb as the first.

When I first started modeling, I used the sketcher as much as possible....until I found out that you can really get yourself into a mess if you're not very careful about managing the sketches and cross-sketch dimensioning.  After that, I didn't touch it for about 7 years.  Since the advent of the NX series, I've slowly started using it again, but that was mainly due to gaining more experience with modeling in general.

Tim Flater
Senior Designer
Enkei America, Inc.
www.enkei.com

Some people are like slinkies....they don't really have a purpose, but they still bring a smile to your face when you push them down the stairs.

RE: Non Sketcher users

The big advantage I have seen with the sketcher feature is the attached spreadsheet for 'common components'.

Say you have a series of bolts, with the same head but different lengths.  Use the sketcher to make a 'template'file - then use the spreadsheet function to create the rest of the bolts, sorted by length.  All the entries in the spreadsheet will have a part number.

When it is time to access the sketch file for a specific bolt - you can access that single entry via sketch file - and put it into your assembly.

MSawtell

RE: Non Sketcher users

Irrespective of how a 'common component' was modeled, with or without sketches, as long as it's fully parametric and all aspects of the design can be controlled by Expressions, the preferred approach to using such items as Nuts & Bolts in an assembly is to use the Part Family functionality.

And if you're a 'citizen' of the PLM World group, you can download for free fairly complete libraries of either Inch and Metric fasteners which have already been set up as Part Families (I know, because I donated the libraries to the PLM World organization myself).

John R. Baker, P.E.
Product 'Evangelist'
NX Product Line
UGS Corp
Cypress, CA
http://www.ugs.com
http://www.plmworld.org/museum/

RE: Non Sketcher users

I want to thank you for those libraries too.  Such a time saver and wow, nice work on it.

Justin Ackley
Designer
jackley@gmail.com

RE: Non Sketcher users

I never use basic curves, it sucks.

But, sketcher has disadvantage too. Fool UG doesn't allow you to delete geometres in sketcher which is used by a extrusion.

Forever Young

RE: Non Sketcher users

"UG doesn't allow you to delete geometres in sketcher which is used by a extrusion."

That might have been true up through NX 2, but starting in NX 3 you can delete sketch curves even if they are used as part of an extrusion profile.  Granted, the resulting model may not be what you expect, but it will let you do it and it will at least try to perform an update.

John R. Baker, P.E.
Product 'Evangelist'
NX Product Line
UGS Corp
Cypress, CA
http://www.ugs.com
http://www.plmworld.org/museum/

RE: Non Sketcher users

Thanks. That is a good news for me. I am using NX2.

Forever Young

RE: Non Sketcher users

Speaking of sketcher, one feature I really miss from Pro/E is the ability to 'replace' one sketch entity with another.  This can avoid downstream feature failures that you might otherwise get by just deleting a sketch entity and redrawing it.

For example, in Pro I could replace a line segment with an arc segment and all the downstream geometry that referenced the line would now reference the arc.

Any chance that this functionality is present in NX5?

Ed

RE: Non Sketcher users

If you're running either NX 3 or NX 4, try this:

Create a rectangular sketch.

Extrude the sketch into a block.

Add blends around the 'top' of the block (if you want to make this bulletproof, use the 'Selection Intent' option of 'Face Edges' when blending the 'top' of the block).

If you're running NX 3, blank the solid and then edit the Sketch.  If you're running NX 4, just edit the Sketch 'with rollback'.

While in the sketch editor, add a 3 point arc selecting the end points of one side of the rectangle.

Now delete the side of the rectangle that the arc 'replaced'.

Now leave the sketch task.

If you blanked the solid, unblank it.

Now look at your results.  Was this what you expected?

BTW, you can actually do this with NX 2 as well, just that it takes a couple of extra steps, but it does work.

John R. Baker, P.E.
Product 'Evangelist'
NX Product Line
UGS Corp
Cypress, CA
http://www.ugs.com
http://www.plmworld.org/museum/

RE: Non Sketcher users

Yes, that is whta I did. Make it reference first. update, and delete. But, just so boring. NX2.

Forever Young

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