To draft or not to draft

This post came to be because of a thread on the SolidWorks forums about whether or not industrial designers should add draft to their parts.

Mark B said they should, and even I said that tooling people don’t have any respect for them if they don’t. In the end, my point is that you need someone in between id and tooling. id people shouldn’t be making tooling decisions, and tooling people shouldn’t have to remodel the id parts.

I’ve run into a handful of id folks who had a “superman complex” and thought that they should be controlling everything from accounting to tool building on their projects. The truth is that many ids do not have the modeling skills to accomplish what needs to be done either from an id point of view or a tooling point of view. It’s a common misconception that id people are somehow automatically born with the 3D complex surfacing gene. Frankly, the tooling people also often lack these skills. An artistic sort dictating the mold is usually as bad an idea as a tooling pro dictating the shape. The reason we have tooling engineers is to reduce the cost of building, running and maintaining the mold.

Tooling engineers often have creative ideas and more often than not are familiar with mold building techniques that id people are not, which is why we hire and defer to tooling engineers in the area of their expertise. Not to mention the fact that there are many different methods of molding. Injection, gas assist, blow mold, roto mold, etc and each type of molding has subdivisions like multi-shot, co-molding, insert molding, foam processes, you name it, and then there are all of the different tooling hardware and process techniques that only people who specialize in that stuff really know. Why in hell would you have the industrial designer pretend that they can maneuver all of this? In reality, regardless of what the id thinks, they do not make these decisions.

If your firm just throws your designs over the wall to the tooling people (to china), then maybe an initial guess is better than nothing, but if you throw your design over the wall, someone else is likely to remodel it to make it manufacturable without your knowledge. I know this because this is where I get a fair amount of my modeling work. I rebuild swoopy translated models to make post-id changes and to align the id work with manufacturing.

I think for complex molded parts you need to have someone who understands the artistic concerns, the tooling concerns, and who is good enough with the modeling tools to bring it all together. I’m not an industrial designer, nor am I a tooling engineer, but I can communicate in both languages. Maybe I support this way of thinking because it pays my bills, but the fact is that it actually does happen enough to pay my bills.