IRONCAD vs Fusion 360 Lesson 17
3D Modeling Techniques Defined
Alternate Sheet Metal Modeling
Streamlined Sketching/Feature Based Modeling

The modeling technique is hugely responsible for the level of productivity. Those of you that are only trained in the sketch, sketch, constrain, constrain world are truly limited by not using the freedom of Streamlined Sketching and Feature Based Design, that is available in even the most Pro/e-ish of CAD systems. If your designers are designing in these very unproductive and time consuming processes it might be time to review your standard design processes. Don't have any do you?

When I introduce IronCAD's very flexible design paradigm I have a hard time to get the Pro/e clone users, like Solidworks and other programs to understand the drag and drop design paradigm.

Download IronCAD/Inovate and take the one day and 17 lesson course. I get rave reviews from my new customers. Give it a try, this is a fully functional 30 day evaluation with all of the native translators so you have access to your legacy engineering information.

IronCAD Self-Pace Training Course

I saw the following video challenge on linkedin and thought I would give it a try. I actually did it before I watched the video, so I did it a bit differently. This will give you an idea how different and flexible IronCAD is compared to the conventional Pro/e clone and to the not so conventional Fusion 360.

Fusion 360 Monthly Challenge: September 2019


Alternative Sheet Metal Design

I was introduced to 3D CAD in 1982 with Computervision CADDS 4, Found PC base 3D CADKEY at Boeing in 1986, Started using and selling it in 1987. This was 3D wireframe, no fancy sheet metal modules. We even had unfolding programs for the wire frame design.

Here is an image of a this part in wireframe. With CADDS 4 we started with one color! Green on Black! They added Color for $35,000 per seat with CADDS 4X. I sold PC Based 3D CADKEY in 1987 with full color with 90% of the functionality of CADDS 4 and Catia 2 for $9000.00 with CADKEY, a 386 computer and 19in CRT. CADDS 4 and Catia were well over $100,000.00 per seat.

The 1980's - 3D CAD - The Beginning

Are you looking up or down? This used to drive the engineers crazy. Yes, in those days 3D CAD was only in the realm of draftsmen!


Enter solid modeling in 1995. We started modeling our sheet metal like we do all of our models.  I am afraid the many of the new millennial engineers really don't know you can probably do your sheet metal design faster and easier than with the sheet metal modules. Now, I suppose if I only designed sheet metal parts it might be advantageous. But most of us design projects where a variety of mechanical design is used. Machining, sheet metal and other fabrication. So you may design just a few sheet metal parts.

Being a Boeing trained draftsman, I have extensive sheet metal design experience. We would do flat pattern development on undimensioned drawings to .005 tolerance. They would photograph them on to the tool.

Today, I just use the basic solid modeling tools. In IronCAD I may grab a feature from the sheet metal module, but that is it.

Here is just one of my many jobs.

IronCAD vs Fusion 360

While creating 3D models from drawing is the very best way to learn 3D CAD and maybe some design techniques is does not expose the designer to the design flexibility necessary in product design. IronCAD is all top down due to the single model environment. Creating mating parts is a cruise. But modeling is just one aspect of a well designed productive 3D CAD system.

I would do a video, but I really am not good at it. So I will show you step by step. I will try and get IronCAD support to create one. They are very good.

I always create the part before I watch the Fusion 360 Video, so as to not taint my process. Of course, there are a multitude of ways to create a model. There is no right way, just more productive ways. From what I have seen from these very complicated processes done by the Fusion 360 fellow, it is not just limited by the 3D CAD system.

Here is IronCAD. My default is inches, so we will set the units to mm. Let's get started.

I drag and drop a block into the scene. I size it 100x50x32

Note: Why does IronCAD call it a scene instead of a workspace? IronCAD was first released as a graphic design program called Trispectives. It still has much of the graphic design functionality. It truly is a wonderful mixture of professional 3D CAD and graphic design, which puts it in a much more flexible category as compared to the Pro/e (Creo) clones.

Look at the small arrow in the corner. All of the Intellishapes are based on sketches. The arrow indicates the extrusion direction. I am going to rotate the block into a different orientation I want to work.

We rotate the block 90 degrees with the Triball. We want to rotate the part, which is shown with a blue outline.

IronCAD has 4 different levels of operation.

Yellow - Assembly
Blue - Part
Yellow - Feature (as shown above)
Green - Face or Surfacee

We will resize it for the new orientation.


we will "Edit Cross-Section" and modify the sketch. I have to tell you this beyond clever!! IronCAD offers flexible functionality beyond any 3D CAD system!

The Fusion 360 fellow made a mistake. Notice the dimension in the Iso drawing are from OML to OML. You have to dimension to the OML to be able to inspect the part. This was a problem in the old day when creating the part drawing. I will show you how to avoid these problems.

Another problem with this drawing is it comes from a center line that is not tied to a feature, hole or edge. This is a no, no because it creates another level of tolerance. You will see my AID (drawing) below showing the correct way to dimension this part for inspection. Even though drawings in the past defined the part, they also were used for inspection. We used to say "You can make the part anyway you want as long as it matches the drawing."

This is how you have t develop this part. Look at the 42 dimension it goes to the bottom OML and 30 dimension goes to the top OML. These points do not connect. You have to create a circle the thickness of the sheet metal and create a tangent.

I will use that line for my diagonal edge. I will finish up the sketch. That is why the Iso drawing is not viable documentation.

We exit and voila we have our base shape. I show it here at the feature level.

Think this through for a second. We created a block, oriented it and edited a sketch.

We add the bend radii.

We just shell the shape.

As I state above I was modeling sheet metal part before they had the sheet metal modules. Now there are very many unique sheet metal functions, and it may behoove you to use them. But for most sheet metal parts this type of modeling is much more productive.

We now have basic sheet metal part.

We now drag and drop a cylinder on to the flange then we drag and drop a hole cylinder to the center of the flange cylinder. We locate with the Triball.

We select the two features, cylinder and hole cylinder in the scene browser on the left, locate and link them using the Triball

The browser is a bit like a history tree, bud due to the single model environment offers much more, profile (sketches), parts, entities, assemblies, cameras, lighting, features in parts and more.

Again we select all of the affected the features in the scence browser and we mirror the features by moving the Triball (You free the Triball with a push of the space bar) to the mid-point of the front edge. You have many locating options with the Triball!

Now for the two cutouts. I am sorry but I am not going to go the a flat pattern to design this part. Most companies do not supply the flat pattern to the supplier. We want them to inspect to the designed part. So I will create the cut outs in the model.

We drag and drop the first hole block, locate and size it.

We drag and drop another hole block on the diagonal face using the exist cut to locate and size the cut out.

I realized had to have a corner for my cuts. I Just created a sketch and the intersection was available to snap to.

We select the two feature, locate the Triball a the mid-point of the edge as we did with the tabs and holes and mirror link the features.

We Select mirror link and we are done with the easy part of the model.

Now for the tough part - blends I right click in the scene and select rendering in the dialog, we select "Show Hidden Lines" since there are so many edged to select.

We put in the blends.

We are done. If you watch the Fusion 360 presenter it is almost tortuous all of the hoops he has to jump through. Honestly, can you see this is a much better design paradigm?

While ISO AIDs are a bit easier to understand, they leave much to be desired to truly define the part. I expect all engineering professionals to be able to understand a drawing, if you can't you will be out the door.

Now we will detail the part correctly. Of course, we cannot really detail a part by itself. We need to have the assembly so we can define relationships of the features so both or more mating parts align. So I will just defined the part so it can be understood by manufacturing and those that may want to create the model.

When converting drawings to 3D you have to re-detail the part to assure it is the same as the drawing.

Here is the AID. IronCAD has a separate documentation module.

All You Wanted to Know About Drawing to 3D Conversions

Unless you are working in a sheet metal house you should send the AID (drawing) and the 3D model to the sheet metal supplier to create the flat pattern. But IronCAD will unfold any correctly designed model.

We select the base face.

Here is the flat pattern model.

We have to create a configuration call sheet metal to create the AID.

We suppress the original part and now we can create the flat pattern AID.

The unfolded flat pattern

So there you go. That is how we modeled sheet metal parts in the past and I still do.

It is very important that you look into how you or your engineers are creating the parts. Streamline Sketching and Feature Based Modeling is easy to learn and implement. It, alone, will increase productivity 10X. Now, IronCAD with its unique integrated history/direct edit functionality can increase your productivity another 5X or more with changes! Again, time is money in engineering.

More on Streamline Sketching and Feature Based Modeling.

3D Modeling Techniques Defined

To experience this increased level of productivity, please download IronCAD for a 30 day evaluation. Legacy data is no problem, IronCAD can read the native files of all of the popular programs. IronCAD is a great replacement for the subscription only Autodesk and PTC products.

Give me a call if you have any questions. I can set up a skype or gotomeeting to show this part or answer any of your questions on the operation of IronCAD. It truly is the very best conceptual 3D CAD system.

TECH-NET Engineering Services!

We sell and support IronCAD and ZW3D Products and
provide engineering services throughout the USA and Canada!

 Why TECH-NET Sells IronCAD and ZW3D

If you are interested in adding professional hybrid modeling capabilities or looking for a new solution to increase your productivity, take some time to download a fully functional 30 day evaluation and play with these packages. Feel free to give me a call if you have any questions or would like an on-line presentation.