3D Modeling-Flat Pattern Drafting

Best practices

Some of the best practices for the 3D modeling are when a customer draws us the material, parts are in 3D, you need to make sure that if it is going to be a bent part they draw it as a sheet metal part, which is a formed part, you can draw it, you can also draw it as a solid part which is basically making it out of a block of material. If they do it that way we have a lot of problems with trying to unfold these parts to get a flat pattern from them, it really needs to be drawn as a sheet metal part which we will be able to unfold.

Solid Works Software

Ideally we have 2 different softwares we utilize here so if they draw their products in a native format then we can take from their software and put it right into our software, there is less conversion. In all 3D software there are universal file formats like STP files that should talk to each other within the different softwares but we found over a course of a lot of experience and a lot of trials and tribulations that if somebody draws something in Solid Works, which is one of the leading manufacturing softwares out there, we have Solid Works here we bring it in there is no issues. Where if you are trying to convert files from a different software, like Neil mentioned, if it is designed as a solid and the software’s don’t like the format they run into a lot of bugs.

So utilizing that Solid Works or the Inventor file, keeping it native to whatever it was drawn in really helps and aids in that process which reduces price as well. I don’t know all the different software names out there to avoid, I know the ones that we prefer are Solid Work files, AutoCAD Inventor files or if they can make it in native files for us STP or an IGES file, we can use them in our systems.

K Factor

One of the biggest things if they draw a part and it needs to be unfolded and it is a part that we would bend. When you do that in the software make sure that you put your correct K Factor in which determines what your blank is going to be when it is unfolded. It is a percent of the material thickness of where this part will be when it is flat, if they don’t have that correct and you unfold it then you won’t get the correct part at the end.

Like Neil said K factor is a formulation used to develop or as a multiplier to figure out what the flat pattern length needs to be, so when we bend a part if there is one bend or multiple bends, that the end geometry is indeed what the customer is asking.  So if you have a single part and you want to bend a one inch lip on it and it is a one inch leg length the flat could be two inches, one inch on the top one inch on the bottom, that is developed in a K factor.  So the flat bit might end up being 980/1000ths verses that one inch, after it is bent that stretch round to the one inch.  So we use the K factor which is a percentage of the material thickness to figure out how much a material will stretch or give.