Wednesday, April 4, 2007

Drafting Standards

In theatrical drafting standards are not nearly as developed as for architectural drafting. Furthermore, the advance of CAD drafting, other visualization software and the different uses for the end product all make the development of a standard difficult.

My stance on drafting, whether it be design plates, shop drawings or anything else, is that it is a form of communication. Thus using the perfect line weight is not as important as communicating what you wish with what you have drawn. The other side of the coin is that using correct line types have communication value, so it is important to know what is commonly expected.

Since I teach drafting, many of these thoughts have been swirling around in my head. So these are the things that I think it is important to think about while you are drafting (though I am sure this will be a partial list).

How will the result be used? Will you have the user a series of plotted pages? Will they receive the file? Will they be transferring your drawing into a machine such as a CNC Router? If they are using the file in addition to the plotted pages, what are they using the file for? Are there things on your plate that could be better laid out, or in more detail so that they can see it on the plate. I consider my self in ways to be a "file" drafter, meaning that I want my plates to be nice and clean and complete, but I also want my end file to be clean and complete. Yet, it still makes me a little nervous when people reference a file over a plate. I think there is more of a chance for an error to be made. I would rather someone come and ask me a question about a plate than try to look it up in the drawings. On the other hand, using the file can be an easy reference for dimensions when a dimension was dropped from the plate. Yet, there could be a reason for the dropped dimensions. there are objects in which there are multiple ways to lay them out (a funky platform lid for example). Depending on how the unit is drawn out depends on the measurements: it could be drawn by using arcs, it could be drawn my plotting points, or by using degrees. By controlling the information you can control the way something is constructed. There is a fine line between two much information, and not enough. The second danger that you face is the lack of engagement of the carpenter. I believe in running a shop where the carpenters are engaged and involved in the work, not in button pushers. I want a carpenter to be able to notice when something doesn't seem right. I feel they should know some of the big picture, and be able to participate. While I think TD's should have hand's on experience, a carpenter who spends all day, every day on the floor may have a method of constructing something that is more efficient than the TD's simply cause they do it day in and day out. In this case it is the TD's responsibility to manage the most effect method of construction versus the overall project. Sometimes a cut corner saves alot of time and money, sometimes it does it at a cost to the production values. But if the drafting disengages the carpenters, I think the shop loses all the way around.

The next is also related; how should the plate be laid out? This depends on how it is being used obviously. I think 1 plate should be inclusive as much as possible. I like to reference other plates in the series or the designer plates. I grew up in the camp that technical drafting was done in 1" scale or larger, and design drafting was done in 1/2" scale. I personally don't feel like most objects drafted in 1/2" scale for building conveys enough information unless it is a very simply object (a standard flat for instance). Also, If 1 plate = 1 object or 1 unit then 1 person deals with the plate. if you draft small, and put lots of things to build one 1 plate you either have to plot multiple copies or the plot gets divided between 2 people. I believe that if the shop is tearing your drafting into sections, then you should probably look at the way you layout your plates, or switch to a different sheet size. And as far as that goes, I have worked in shops where 8.5x11 or 11x17 sheets were used very effectively. Bigger isn't always better.

At any rate, the other thing I wanted to mention was a website that has some standards related to CAD (USITT also has a published set of basic standards). The link is:
It provides links to the Canadian division of USITT and an English version, as well as information about drafting within the site posted as well.

No comments:

Post a Comment