Is Design Going Down the Toilet?

A Fascinating Retro-Fit

 When "nature called" at a restaurant, what I found was design literally in the toilet*.

*In Australia toilet = restroom.

 On entering the restroom - the first thing I noticed that the toilet was very close to the door when I opened it.

A troublesome predicament

 I thought, "There's something wrong here!", but couldn't tell what it was at first. The room was dimly lit, so it took me a couple of seconds to work out what I was seeing, but the shots were pretty good from my mobile camera and really makes it evident what I’m talking about.

  I noticed something between where the toilet is, and the door:  Primarily that the door looked really close. But then I looked at the edge of the door. Did you see it in the image above?

Is it Damage or "Design"?

 Initially I thought the toilet door had some sort of damage. But no, it was deliberately cut out. And cut with what looks like a hack saw. You can even see how the first cut above was a little too high or so the tradie thought. You can imagine – the designer going “They’ll notice that cut, I should make it a little lower” ha ha.

Damage or design?

 Even more amazingly, with the toilet lid down, you can't open the door to get access to the toilet. So that first retrofit cut on the door, the mistake was actually the right one. With that cut, the door could at least fully-open with the toilet lid down. The “designer” didn’t double check…

Why the Big Fuss?

To me it looked like the door was put on after the cubicle was installed, which would be the sensible thing to do. And it had to close inward due to the entry into the bathroom itself.

  It led me to ponder...I guess design consideration was only made for the clearance to the toilet after the install. Once the door was mounted there was nothing else to do but make a modification. And boy, is that modification a piece of work.

 Why am I making such a big deal out of this? Let’s ask these questions: 

• How long did it take to cut out that clearance recess? 
• Were any other trades delayed (painter, tiler etc)? 

 It looks like the painting happened before the install as the recess was not painted. To me it seems that the owner missed this or may care too much about what their customer's think. As a customer, seeing things like that, gives the impression of tardiness. What's going on tin the kitchen if this is how they look after the bathroom?

Herein lies the problem

  Perhaps measurements weren't taken accurately for the toilet install, or the room was retrofitted on the fly by trades’ people (or tradies). The main thing for me was that modifications onsite were needed and delays were caused. The result was a poor functioning door and the idea of a door for privacy was rendered useless without the modification.

  So what does an engineer do when faced with this issue? It can be catastrophic from an engineering and manufacturing perspective, especially when we are dealing with machinery or equipment that needs to be installed and commissioned in a cost and time-effective manner.

The Right tools

  Using the right tools designed to work with manufacturing in mind is paramount. What are the right tools?

 When I went to technical college, we got a glimpse of CAD, but the tools were mostly pencil/pens and tracing paper - believe it or not (for those that were born in the late 80's and onward). We had exercises to create either the relative 2D views or sketch out the 3D isometric based on partially complete 2D technical drawings in our texts that were drawn in 1st angle or 3rd angle projection like in the image below:

Source: Engineering Drawing 3rd Ed. A.W.Boundy

 Those days were fun of course, you really had to work your brain to work out projection lines, and show hidden lines, break out views etc. but the amount of time it took was long. At the time, you accept this as the most efficient/affordable tool. Of course we want to get things done faster, easier and better; minimise or remove errors.

2D Computer Aided Design (CAD)

 So then 2D CAD came along. Now on a computer screen we can delete lines, scale them, move and copy. I use both 2D a.k.a. CAD (describing two dimensional Computer Aided Design) and 3D Solid Modelling Design to get work done. 

2D CAD can assist you in being able to accurately represent at full-scale, the components and machines you are building. Depending on the complexity of the job, or my clients', I might choose either, or a combination of a 2D and 3D CAD package.

 Sometimes I am supplied DWG files (2D format); depending on the job, I’ll be expected to use portions of or the whole file to create or update a product. To edit, copy or modify the original drawing it is handy to have more than a DWG viewer to read the drawing.

2D detailing in Draftsight

 If I am using a 2D CAD package, then being able to view and edit is great. But even more-so when I want to create a 3D part - I can copy and paste directly from the 2D CAD directly into the 3D package.

 In this video by the team at SOLIDWORKS you can see how to take a 2D DWG file, edit it, then bring it directly into a 3D mechanical design system that shows how can utilise both 2D and 3D tools in harmony. 

Coverting 2D to 3D in SOLIDWORKS

Where does 3D CAD come in?

 So why is it important to be able to visualise your models in 3D? In the image below you can see the finished product (as mentioned in the video above). 

 Not only can we visualise, but we can take several components and assemble them like you would on the shop floor. There are videos by SolidWorks on Youtube to see how it’s done. 

A 3D Solid Model Generated from a 2D DWG

 Finally once assembled, you can test whether the parts will interfere - you can tell right away whether parts will collide! Here’s another video showing interference detection.

 In the first example I made the assumption that a digital tool was not used, but there are many factors that attribute to these types of errors: Sometimes the drawings are not clear, the parts lists are incomplete or maybe the specifications were wrong. Other times the drawing is clear but the floor plan is incorrect or incorrectly measured up.

Closing Note

 Having quality work reflects on you and your establishment, let alone the danger if we put this into an engineering perspective.

 Those factors aside - I think this article demonstrates that you're better with CAD, than without. And Computer Aided Design is certainly not going down the toilet, far from it. We’ve heard all about 3D printing and additive manufacturing, CAD on mobile, CAD in the cloud. Technology is continuously improving and new ideas are being forged.

 With CAD, we are able to visualise designs, test our parts and assemblies and make informed decisions about the design process, but rushing into anything will probably get you into trouble.

 If you have a project or an idea and you’re wondering how to get started or get it to the market, contact me.

Happy Designing!

Unfold Your Design Potential - Part 3

You may have seen Unfold Your Design Potential - Part 1 where I introduced the Fatten Surface feature and in Part 2, how it worked. In this final post, I take a look and see how we can use this information for manufacture. I also discuss a couple of questions and highlight enhancements to come.

Analyse for Manufacture

Once we have got an idea of the size of material needed, we start to think about quoting and manufacture.  It’s important to understand how much and where the material will stretch or compress when it is folded, or formed into the final shape. As we know when some materials deform, they have higher tendency to create stress concentrations in those areas, resulting in potential cracks that lead to material failure. You can see the results of cracks leading to material failure in the image below. 

Glasses case

My CAD model below in the deformation plot below isn’t perfect, but it seems to correlate with reality, showing me where the stressed areas are. Increasing the mesh quality, and some more control points will increase the accuracy of the deformation values, making them more realistic. I could also sped a bit more time modelling for accuracy.

The Deformation Plot

In the CAD model I made I did not spend enough time to get the flexible hinge of the cover perfect, but we can see the stretch/tension in the area of interest.

Prepare the Cutting Profile

Once the flattened shape is created, you end up with an extra single "Surface-Flatten<n>" in the feature tree.

Extra Surface Body in the Feature Tree

 Now you need some sort of 2D profile for quoting or for manufacture. How do we do that? We can make a 2D drawing from our 3D model and that is needed with many company design procedures. Some companies' processes determine the need to see a title block and a checking dimensions to ensure that the person on the other end has something to verify the DWG against. But if you need just the DWG, as with most tools in SOLIDWORKS, the feature is accessible from the Right mouse click or Context Menu> Export to DWG.

Preview of Export to DWG 

You get a clear preview of the shape and also have an option for orienting it prior to saving. This flattened shape can be sent off for nesting and cutting. We design processes don't stop there, but the feature has done it's job at this point. 

What if I Don't Have SOLIDWORKS Premium?

As the title suggests, you need SOLIDWORKS 2015 Premium and later to enable use of the Flatten Surface feature - Some questions follow: 

Q: Can the file be shared with another CAD user that does not have 'Premium? A:  Yes. For those who aren't using SOLIDWORKS Premium, the file shared with others will still contain the feature and the fattened surface, but the feature can't be edited in SOLIDWORKS Professional or Standard versions. However, the surface created can be viewed and manipulated as in a regular SOLIDWORKS part: Put into a drawing, save out as a dwg and saved out as a separate body. 

Q: Can the flatten feature have different amounts of stretch applied in different areas? A: At this time there is only mesh quality control.

The Final Piece - Determine if Fatigue is a Factor

We've covered several of the main points here - but I left one out. To use the tools that complete the full development cycle of a virtual lab environment, analysis on the glasses case for fatigue would be appropriate. We already saw from the previous posts that the glasses case was breaking and as I write this, the only thing holding the back and front together are the threads that have sewn them together - the formed material has now completely failed. But the sewing thread is still intact!!!

The case of the missing flexibility :-)

I would love to see how the repetitive load on the cover - the motion from opening and closing the case - would result in failure and how long I should expect it to last.

I would like to have used Fatigue Analysis but I don't have the software or projects to justify the outlay. If you have the software and would like to publish results or share with me, you've got the model here. The material might be PVC, but I can't be sure. However, it would be an interesting exercise...

Further Information

There are limitations as you'd expect for the first release of a new feature - it won't flatten if the surfaces are not joined or there's a hole in the middle. As I saw in in Michael Lord's blog, that limitation should be resolved in SOLIDWORKS 2016 - his photo journal from SOLIDWORKS World (SWW) 2015 - you'll find the reference about half-way down. :

Showing Flatten surface with holes in SW 2016 - M.Lord's photo from SOLIDWORKS World 2015

Normally what they show at SWW is only a hint of the enhancements that you get to see when the software  is officially released. I'm looking forward to new tools and the ways I can use them.

That's all for now. Catch you next time!

Unfold Your Design Potential - Part 2

At the end of my last post, Unfold Your Design Potential - Part 1, I told you where to find the Flatten Surface feature. Now we'll take a look at what happens and what options we have to play with.

Flatten Surface!

Unless your part has a matching surface, there is one step to do prior to flattening. You need only surface bodies, and one of the quickest ways to get one or more surfaces is to use the Offset Surface command with a zero distance like in the image below. You're essentially creating a copy of the surface and it's what you need to generate the flatten profile.

In the part I made, I created a solid after trimming away surfaces - that's my way of determining whether the surface is without gaps. It doesn't guarantee that everything is perfect but you can tell if your surfaces are touching: A solid won't work if there are gaps in the geometry. Then we add the Offset Surface so it can be flattened.

This Flatten Surface tool will allow you to flatten surfaces that are in contact with each other, but you won’t need to "knit" all the surfaces together to use this feature. Multiple surfaces are part and parcel of creating complex shapes and SOLIDWORKS seems to have made it part of the thinking process to get to the end result needed.

A Mesh Quality Preview

Developing the flattened material shape is almost instant depending on your surface and mesh quality settings. The folks at Javelin show you how it works in another scenario in this video.

Determine the Surface Elements

You can review the flattened surface when the command is active to see the mesh quality. It has created a triangular mesh of all of the surfaces and then a as a colleague of mine suggested, an algorithm is applied to flatten out those triangles. The greater the number of triangular elements, the longer the flattened surface will take to generate.

Preview of the mesh and flattened shape 

During the flatten process there are also a couple of other options relating to the flattened shape. You can add a control point or edge to determine from where you want the start point of the unfolding or flattening to be. And further control can be added to the flattened shape by selecting edges to be maintained after the surface is flattened. In my case I used a point at the centre of the part and a few edges to control the flattened shape.

Further options to define my Flattened surface 

So that's the end of Part 2 - In the final segment, part 3, we take a look at how we can manufacture this flattened surface and also touch on some other sources and developments of this feature.

Unfold Your Design Potential - Part 1

Software Looks Good.

In software demonstrations (demos), things look really nice, quick and seamless – demos are designed to be smooth, interesting and memorable. If you had the opportunity, you might have seen the SOLIDWORKS 2015 presentations, "Innovation Days", at a re-seller near you. As a CAD user, being able to see new features and understand the benefit, gives you the idea that you have better tools to help you and you’ll be able to do more work in less time…

The CAD software company invests a lot of money and time to prove these things to you, but often it’s not until you’re working with the software or in a training class that you find how effective it is. Coming from a Product Design background, I had a keen interest in how this tool would work, so I did my own research and this post is about that process.

 When I was working at Dassault Systemes, I presented some of this content to customers and reseller alike. For the Flatten Surface Demo there was a complete shoe body shown. From that shoe, the result was the a surface that represented a part of the toe cap as below. 

The toe cap with spline on surface for intended split

 From the toe cap, another feature was inserted to define it even further. The Spline on Surface tool allows you to create a 3D spline which attaches itself to non linear surfaces and you're able use that same spline to trim away the unwanted elements. Pretty handy stuff.

The flattened toe cap

Finally from the trimmed portion, a new tool was used that has not been seen before. “Flatten Surface” was introduced. Magically, the organic shape was flattened. For me that was exciting enough (yes: CAD Geek) Then other elements were shown like how to improve the surface quality through the mesh style, the deformation of the product in different areas and ways to take it to manufacture. What good is a product if you can’t manufacture it?

Use a Real-World design

I'm part-way through a project and then realise I need to flatten the surface. Before this tool there would be a LOT of guesswork. In fact, I wouldn't even consider it. Generally for a one-off it's not worth it to have this functionality. So what do I do? It’s CRUNCH time! The boss is waiting on the design you’ve been tasked with and you don't have many options available.

I thought about that scenario and how I could demonstrate this new tool effectively in a so called "real-world" job. My trusty glasses case came to mind - they've been deteriorating for some time but held their shape and seem to have been made from a flat shape and formed into what they are. It's a thin flexible plastic case with a velvety finish on the inside to protect the glasses. There’s a button clip to close the case and it’s quite tough.

Trust Glasses Case - Front

In the images following you can see the case in the closed and open position. There is also a stress crack along the top of the case (below: red arrow) which developed over constant opening and closing: necessary to remove and replace the glasses as needed. Seeing this case and the crack in it, I wondered if when designed, the case was considered to be a throw away item and how long it would last. Firstly I wanted to understand how large the piece of material would have to be to create that shape and then I realised where the flatten surface function could be put to the test...

Glasses case rear showing the cracking surface

Glasses case in the open position

Analyse the Design

So how do we go about designing this case in the first place? There are many ways to create this part, or parts. Using SOLIDWORKS 2014 and earlier, the process would not differ greatly. I used several of the Product Design tools in this case: sweep, loft, and surfacing. And in SOLIDWORKS 2015 you won't find many differences to the approach and the techniques I used. I started out with basic overall shapes and trimmed them back - you can take a look at what I modelled here. 

The rough CAD model

I used surfaces mainly for the flexibility, then thickened the whole surface into a solid. It's a bit easier to work with solids in an assembly and drawing. You’ll notice the 3D model has only one part when it should actually be an assembly of 4 or 5 components, including: The outer cover which acts as a flexible hinge to open, the inside portion that supports the glasses, a lining to protect the glass from scratching, a “nose” support piece (not visible) and a button clip to hold the glasses in. The model is not completely accurate, but for the purpose of the exercise it’s all that’s needed.

Building Complex Shapes

If you have not used SOLIDWORKS to design complex or “organic” shapes then you can use the online help in the form of tutorials, the SOLIDWORKS online Help found under the option HELP and finally there is always new content on My.SolidWorks (I wrote a short post on that here). Whether it’s a SOLIDWORKS blog post, videos, forum posts, you'll most likely find it there.


With a part, working out the area is fine – I can use the Evaluate tools to do that – Area, Mass, Centroid, Distance, Thickness analysis etc. are all easy to discover. I can select several surfaces to get an approximate area. Except when I want to get the part made, how can I determine how much material to use? Estimating the size of the material is always going to be tricky. In SOLIDWORKS Premium 2015 with the new Flatten Surface feature, I can select a surface and just click “Surface Flatten”.

The Surface Flatten tool is available from the Insert Menu> Surface> Flatten

This is the end of Part 1 - In Part 2 we'll see to how to unfold it...