Double Spring Open Drawer Prototype

After what seems like too much time was spent out of the shop, I'm finally back in and working.  A combination of illness, business trip and work on the new lumber shed took up most of my free time and energy.

Following on from my earlier posts about refining the drawer catch mechanism, I came up with the idea to make two of them which would sit to either side of a center divider.  This will allow a pair of drawer to spring out (when activated) from either side of the box.  I shrank down the drawer catches a bit and put them into the floor of the box.  As you can see in the photo, the catch still has a hinged portion with a screw holding it in place.  At the rear of the catch a small pen spring sits underneath so that the catch is always engaged.  I designed these drawer (more like trays) to be much smaller than my earlier version so that springs would be pushing much less weight.  These are meant to store small, light item, not lead weights.

The springs are made from an old bandsaw blade.  I only had a 1/2" blade handy, so that's what I used.  I cut some pieces to size, then ground off the teeth on a grinder (it's really fast and easy, just use some pliers to hold the blade steady and don't grind for more than a few seconds).  Then I put the two bends in and drilled some holes for the mounting screws.  These will flatten out a bit when closed, but the still retain a good deal of springiness.

The chunk of dowel is what activates the spring catches.  A simple press pushes the two catches down, at which point the lip of the catch is below the surface of the floor and the drawers will pop out.  It's a simple thing, but yet neat to watch.

I haven't tried heating the metal before bending yet, but I hear that can help the spring always retain it's shape.  I think (but don't quote me) that many bandsaw blades are made from a variety of spring steel.  In reading a bit I learned that to get a spring to hold it's shape you should heat to red hot, bend, then quench.  Then heat again (not sure what color) and let cool naturally.  The issue with these is that they will heat fast, cool fast and be prone to breaking.  But I plan to give this a try later.

This box will likely have a second layer on it, slightly smaller.  It's a tiered design I've seen on antiques that I really like.  The drawer will activate via a button in the floor of the second tier.  I'm even thinking of adding a puzzle to be able to open the lid of the second.  But, one thing at a time!

Posted on August 30, 2015 .