Tips that speed and simplify enclosure modifications: Part 2

Carefully weigh the pros and cons of making enclosure modifications in house. The break-even quantity for saving money by having the manufacturer perform the modifications is around 50500 pieces depending on the manufacturer, but it also varies based on the type of modification you need and the capabilities you have in house. If all you need is a drill press, it’s probably doable in house, but if you also have to pull a worker off the shipping dock to run it, make sure to factor in the cost of not shipping for a few hours or the cost of overtime. Other modifications, such as silk-screening or painting, require equipment you probably don’t own.

Many OEMs who consider handling modifications in house don’t know they shouldn’t use the same drill bit for metal, plastic, and fiberglass, and they’re unaware of the torque speed required to cut a polycarbonate box without cracking it. Therefore, if they absolutely must do modifications in house, they should plan for a certain amount of scrap. On some projects, the cost of modifications at the supplier will be just a fraction of the cost of scrapping an enclosure.

Here’s what’s involved in working with an enclosure supplier to handle the modification process. First, download or request a DXF or STEP file, which may be available on the manufacturer’s website. Then import the file into your CAD software and indicate where the modifications should be located. The supplier will work from your file. The vendor will then use its expertise to verify your design and ensure that it will perform as anticipated.

Having the enclosure manufacturer make the modifications is usually the most economical decision. Order in the largest quantity that makes sense to minimize cost. On an automated milling machine, the run time is only 30 to 60 seconds per enclosure; setting up the machine takes the majority of time. Robotic equipment can modify multiple box sides with only one setup. Although job shops may be more cost competitive on shorter runs with just one setup, OEMs will incur extra freight costs and shipping time, and must deal with multiple suppliers.