Reflecting on the Past, Focused on the Present, Looking to the Future

Posted on Wednesday, August 9, 2017 in UEA Blog

There have been great improvements and advancements in designing tools over the past 40+ years. From the beginning days of designing using a drafting board to implementing 3-D modeling, it's been very exciting; although along the way sacrificing the human element.

There's nothing wrong with learning how to do things the long way in order to appreciate doing things a quicker, more simplified way. Back in school and starting out in the field of machine and product design the instruments were very basic. The primary tools used were the drafting board, T-square, scale, triangles, templates, protractor, compass, pencils and eraser. Line weight of your drawings was controlled by sharpening the lead tip of the pencil using a sand paper block. A Gum Eraser Bag was used to sprinkle eraser crumbs over the paper to prevent the lead from smearing. An eraser shield was used to remove unwanted construction lines. The mechanical pencil and the electric eraser are a couple minor improvements made along the way

The next improvement was the use of an articulated arm and protractor. The articulated arm allowed freer movement over the drawing board. The protractor contained two scales one, 18" and a 12". This eliminated repositioning the scale to draw horizontal and vertical lines to the desired length. The protractor head provided the ability to draw lines at any angle. Then there were the horizontal and vertical beams, also including the protractor head and scales; which allowed for even greater flexibility. This increased the size of the drafting board and allowed the designs to be created on rolled size drafting paper. However, the scale of the layout had to be predetermined in order for the machine layout to fit on the paper size selected. When the design of a machine or product was complete, individual part drawings were created. That meant completely redrawing the part. The part drawings contained all the information necessary for the shop to make the parts. Blueprint machines were used to make copies of the prints for the fabricators. The raw materials and purchased parts were ordered from the bill of materials on the drawing.

Then along came 2-D computerized design. This provided limitless design space; which meant everything could be designed at full scale. Parts were designed using layers and assigning a color. This allowed anyone to visually see individual piece parts within a design layout. Design layouts and part drawings were still constructed using orthographic projection, normally constructing three views in order to visualize the completed design and parts. Individual part drawings were completed faster by freezing all the other layers. When design of the layout and parts were complete they were scaled up or down to fit on the selected paper size.

The initial start of 3-D was very complex. Commands were in word form and were often found buried in cascading menus. Now commands are both provided in word form and through icons. Assemblies can be created from the top down or from the bottom up. Three main parts of design are assemblies, parts and drawings. Parts are created starting with a sketch defined by dimensions and associated with a plane, then they are either extruded or revolved. Parts are then inserted into the assembly and the planes of the parts are mated to the assembly planes. Parts in the design are termed to be parametric or dimension driven. Once a part is modeled the dimensions can be modified and the part will rebuild to the new constraints. In some software packages both the part model and drawing are parametric. This allows for either one to be modified then both will automatically update. A material designation, along with an appearance, can be assigned to individual parts. This allows for the designer to determine the overall weight of the assembly. Drawings are created from both the assembly and part models. After learning the design process from the ground up I've certainly learned to appreciate all the benefits that designing in 3-D has to offer. This often leaves me wondering how technology will progress even more so in the future to improve the design process to make businesses more efficient.

Thomas Van Veldhuizen