ZW3D 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?

I am not sure if it is due to these exercises but I have replaced a few Fusion 360 with ZW3D. Listen to what these two fellows said.


"We spoke a year and a half or so ago about ZW3D. I took the Autodesk Fusion 360 but am becoming increasingly unhappy with it… It’s not very productive for me, just too slow and cumbersome to get things done quickly. On on the strength of your recommendations I am ready to give ZW3D Standard a shot, probably as a rental for the first year.

Bottom line is, Fusion 360 is “free” but not really free… I am finding that the slow, clumsy pace of design with it is counterproductive… time is money."

Thanks much,



The initial hull design was done in Rhino, which for some reason is a standard in the boat industry.

The surface already had a few problems!

It was imported into Fusion 360 and I did some of the early concept design work, but when it came to surfacing I hit road blocks every way I tried it.

At this time Phil was not part of the project, but I suggested to my client that we needed Phil's help. Phil also hit road blocks in Fusion 360 even using some of his unique re-topologizing workflows and T-Splines.

The rest is history, as they say. 

Thanks to ZW3D paired with Phil’s surfacing skills we now have tooling for the hull created.

You should see the images.

Perfectly smooth reflections! 


I saw the following video challenges on LinkedIn and thought I would give them a try on IronCAD. I got a great response and decided to do it in ZW3D. I was very familiar with the parts and did it a bit easier. It shows more the difference in the level of the 3D CAD experience than the CAD system itself. You can Download ZW3D and give it a try.

Fusion 360 Monthly Challenge: September 2019

Look at the this drawing. Who details like this? It is obviously dimensioned only to be able to easily create a sheet metal model with the sheet metal tools. No where in the world would they detail a drawing like this. How do you inspect it? We are going to get it back to reality.

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 wireframe sheet metal part. 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.

ZW3D vs Fusion 360

ZW3D is very similar to Fusion 360 and the Pro/e clones with differences that make it much more streamlined. It is very easy for those users to get up and running with ZW3D. The unique benefits over the other systems is the multi-object environment, for easy top down design and the the integrated drawing. You can do complete projects (parts, assemblies and drawings) in one file. Imagine how much this would simplify PDM? 

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 ZW3D support to create one. They are very good.

These have actually turned these into exercises in modeling techniques as compared to showing a more productive CAD systems. Again, I say there are many different ways to model a part. I see with my exposure to direct edit modelers like CADKEY, I rarely sketch like you see the Fusion 360 fellow doing. I have always created my basic sketches by mostly creating offsets and extending and trimming. It seems to be much easier. I never put in a fillet that can be created later. What do you think? Of course, this take a good understanding of descriptive geometry.

Creating this model without using a sheet metal module would be a snap if someone understood you just don't dimension parts for the sheet metal module. So lets get started.

We select new file and select Part/Assembly since this is a single file. ZW3D offers a Multi-Object environment to do top down or in context design

We will name this Lesson 17

Here is ZW3D. My default is inches, so we will set the units to mm. Let's get started.

We create a sketch on the YZ plane

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 to develop this part. Look at the 42 dimension it goes to the bottom OML and 32 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 just sketch the bent feature. Showing the geometry necessary to develop the cross section from the drawing.

The dimensions are only shown for clarity. I do not use constraints in my sketching.

Here is the complete sketch I will put the fillets in later. Using standard sketching tools like mirroring and offsets.

We exit the sketch and extrude the profile.

Create the fillets. You shouldn't sketch fillet unless absolutely necessary

We shell the shape. This is how I have designed sheet metal since the introduction to solids in 1995!

We insert a primitive cylinder locate, size it and set it to add.

We now will pattern the tabs.

We insert a hole in one of the tabs

We pattern them

We create the sketch for the cutout.

Exit the sketch and extrude remove.

We just mirror the cutout and we are ready for the hard part.

Now for the fillets! I turned in to wireframe to make the selection easier.

There you go. Go back and watch the poor Fusion 360 jump through so many hoops. Sometime I just don't know why he makes it so hard.

ZW3D is one of the few 3D CAD systems that has integrated AID (drawings) you just select 2D sheet and create your documentation. With its multi-object environment you can do complete projects in one file.

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.

All You Wanted to Know About Drawing to 3D Conversions

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.

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