Documentation
We expect clear instruction on what to do and what is expected. All of our internal processes are documented and controlled. If we prepare drawings and instructions, we expect the customer to approve them before production commences.
Our preference is that the customer prepares drawings, artworks and instructions.
Our preferred format is either paper or PDF or other files that can be read by Adobe.
As chemical milling is a partly photographic process, manufacturing relies on photographic images, i.e. black on clear polyester film. The preparation of these images is important for they are the production tool. Usually there is no difficulty in preparing a drawing or an artwork for graphic work. Preparing the artwork for chemical milling however needs attention to allow for undercut. Figure 1. shows that as chemicals etch downward metal is removed from the side wall. The illustration shows that a width of resist 10mm wide actually yields a width of 9.5mm on 0.5mm metal. Undercut is usually about half of the metal thickness and by allowing for this great accuracy can be achieved.
Our preference for supplied artwork is that the lines drawn are not less than 0.2mm wide, preferably 0.4mm, drawn such that the inside edge is the part plus the undercut factor. Any, and all fold lines, and side sensitive detail, or secondary detail are in this image. i.e. all sides and all detail is on the one image. We prefer to be supplied with one image only, and that image has scale bars in x & y that have a stated length to allow us to check sizing. A secondary drawing shows what is to be on each side. A mechanical drawing contains final dimensional information. A 'sketch' or isometric drawing is also most useful. This is all required in order for us to get it right.
