Coordinate system bafflement

[GeoffKornfeld]

Hi, newbie here.

I've been trying to create the object in the attached image and also keep it as parametric as possible, but I can't seem to figure out how to create construction lines in multiple coordinate spaces. Is it doable?

A little background: 30 years ago I was a young AutoCAD wiz (before becoming a mediocre animator/3D generalist), and this image came from one of the drafting textbooks that I learned from. I also taught an AutoCAD solids-modelling class at the time, and this was one of the more challenging problems I would have my students tackle. This is totally doable in AutoCAD since you can quickly align the coordinate system however you need as you work, but I can't figure out how to do this in Fusion.

Thank you!

[TheCADWhisperer]

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@GeoffKornfeld wrote:

Hi, newbie here.

I've been trying to create the object in the attached image

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@GeoffKornfeld 

Can you File>Export your *.f3d file of your initial attempt to your local drive and then Attach it here to a Reply?

Is this a Giesecke textbook exercise?  If yes, what chapter?

[TheCADWhisperer]

@GeoffKornfeld 

Step 1.

Start a new sketch on the XY plane and sketch a line in space and dimension as shown.

Now add a Midpoint constraint between the line and the Origin...

[GeoffKornfeld]

I don't see how to switch from creating lines on the x/z plane, then switch to creating them on y/z plane, then switch to creating them on x/y -15° plane. Again, I'm a total newbie with Fusion. I've been looking all over for tutorials that do things similar to this and I'm coming up with nothing. At one point I had somehow switched my WCS, and was able to continue drawing on another plane (dunno how), but for some reason that caused my previous sketch to get deleted.

I haven't really created much work to show. I'm really just trying to create lines on multiple planes.

Oh, and the textbook this comes from is ancient. "Engineering Drawing and Graphic Technology" 75th Anniversary Edition, from 1986.

[TheCADWhisperer]

Is the editor Giesecke?

If yes, what is the name of the chapter?  (I taught using this book for 30 years.)

I will create video on the steps. 

I am almost done with the initial attempt...

[GeoffKornfeld]

Oh fantastic! Thank you. I look forward to the video! I don't see the name Giesecke anywhere, but it says it was edited by Kiran Verma, and J.W. Maisel.

[TheCADWhisperer]

I just have to add the small fillets and I'll have it done.

It will take me a while to create video(s) on the steps.

[GeoffKornfeld]

Great work! I was able to crank it out in 3DS Max a couple weeks ago, but wasn't able to retain much of the parametric stuff there.

[TheCADWhisperer]

@GeoffKornfeld 

Is there a note for the size of the small fillets?

I might be missing it, but I don't see the radius specified.

[GeoffKornfeld]

I'm afraid there isn't any info on fillet size for any of the problems in that section of the book.

[Drewpan]

Hi,

I would strongly recommend that you do the embedded tutorials in the Fusion Documentation and also some of the

Self-Paced Learning to help you to learn fusion faster and better. They can be found here:

It is also much easier for the forum to help you if you attach your file AND a screenshot of what you want to achieve

and what the problem is. You can create a file to export like this:

Time spent on the tutorials and self paced learning will not be wasted. Also check out the three RULES that are

pinned to the forum for further guidance.

I feel your pain. I transferred over to fusion from AutoCAD also and struggled until I realised that even though

both Apps are CAD, there is a BIG difference between DRAFTING and MODELLING. Sure there are many cross overs

and common techniques but they are NOT really the same. I got started hitting the Docs and the Self Paced

Learning and it really helped a lot.

I also struggled with turning a 3 view 2D shape into a 3D model at first. Then I learned about Projections. The easiest

way to model this shape is similar to how it is done in Drafting. Model the Top view on the XY plane. Create a new

sketch on the YZ plane and Project the Base line onto the new sketch. This is the same as drawing vertical lines from

the Top view so that you can then draw the Side View in exactly the right place. Then draw the rest of the side view

on your sketch. Finally start a new sketch on the XZ plane and project the Height line from the Side View sketch. Now

you have the correct height from the Side view, draw the rest of the Front view.

When you are done you should have three sketches perpendicular to each other and with the dimensions of the 3D

object. You now simply extrude these shapes where you want them to get the basic 3D model. After you have the

basic model you can do things like apply Chamfers, Fillets and Holes with the tools. You even get a leg up because

you can Offset Extrude Symmetrically some of the shapes.

@TheCADWhispereris great. He helped me a great deal as I was getting started. I am sure he has the patience of a Saint

to put up with some people who are slow learners - like me (a slow learner). He has corrected me many times and I am

grateful he did. I have learned many things with his help.

Cheers

Andrew

[TheCADWhisperer]

@GeoffKornfeld 

I am in the process of recording a video on my steps to complete the model, but in the meantime I sent you down the wrong path in my initial response.

Start Sketch1 on the Right Side plane.  They kind of gave a hint for this in the image.

@Drewpan 

Before I attach my video - give this one a shot and post your result.  It is challenging at first, but I will make it quite simple to solve in my video.

[user015M86Y]

@GeoffKornfeld @TheCADWhisperer 

Here is my proposal

On my side the most difficult is the junction of the inclined plane with the trunnions
On the outside the inclined plane is flush with the outside face of the trunnion

[TheCADWhisperer]

@user015M86Y 

Hint:

[user015M86Y]

@TheCADWhisperer 

I started with a rectangular base plate
I didn't see that the base plate was trapezoidal
Indeed the design is much simpler than I imagined
Thanks for the correction

[user015M86Y]

@TheCADWhisperer 

I was wondering if we can do the dimensioning of the model on the isometric view like the model attached by @GeoffKornfeld

[GeoffKornfeld]

In AutoCAD, back in the day, I would create a framework of many of the dimension lines in 3D space, as seen in the drawing, and build off of those, while flipping and aligning the UCS as needed. I really just want to learn how manipulate the coordinate system in Fusion (or whatever Fusion's method is), and this object is simply a means to get to that understanding. The object itself I understand very well. I'm just having trouble finding tutorials that get to the knowledge nuggets I seek.

I've been pretty busy with some other things the past couple days, hence my lack of responsiveness here. But thank you so much for the efforts!

[TrippyLighting]

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@GeoffKornfeld wrote:

In AutoCAD, back in the day...

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Forget AutoCAD. It's not a parametric CAD modeling software, and that allows users to do things that aren't possible in parametric CAD software. This isn't particular to Fusion but applies to most parametric CAD software e.g. SolidWorks.

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@GeoffKornfeld wrote:

... I really just want to learn how manipulate the coordinate system in Fusion ...

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Right at the beginning of the first sketch, you decide how the component's origin is oriented and located in reference to the geometry you are creating.

In other CAD software, you can specify additional origins/coordinates systems/frames. In Fusion, that isn't possible (yet).

You can re-orient the geometry within a component using the move tool, but usually, for people new to Fusion and parametric CAD modeling, we strongly advise against it!

[TheCADWhisperer]

@GeoffKornfeld 

I am working on a video of the steps.

Takes me about ten times as long to edit the video than it did to record the video.

[TheCADWhisperer · Accepted solution]

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@GeoffKornfeld wrote:

In AutoCAD, back in the day, ...

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@GeoffKornfeld 

Except for the Delete Face step - I would model exactly the same in AutoCAD.

Let me know if you have any trouble and be sure to Attach your model here.