I haven’t talked too much about Inventors Digest lately, but a recent article really hit the spot.  Inventors Digest is a pretty good magazine focused on invention stories, patent law and other invention developments.  In the new issue there is a new article on holiday gifts for inventors which was interesting.   After reading I remembered that I had just gotten myself a great inventor gift that was not mentioned, a digital caliper.  Basically it is a very precise ruler that is great for small items with a digital readout in inches and millimeters.  Here it is measuring the diameter of my pen cap.

Why do I need such a fancy ruler?  Well we do a lot of modeling around existing items.  For example if you want to incorporate a bottle cap into your design you need to know the exact dimensions.  Sometimes you can get lucky and find a spec sheet on the bottle cap and work off that, but not always.  I managed to get by because everyone else had one of these.  All designers, engineers and manufacturers have this tool to help them precisely measure the bottle cap, (remember bottle cap is just an example).

Unfortunately purchasing this item was not as easy as it should have been and if you are interested I thought I would just share.  I found it on the Home Depot website and it said that the calipers were in stock at my local store, but they weren’t.  So I bought it online for about $45 and you should do the same instead of walking around Home Depot in circles.