60 Second Rule

One two three four five six seven eight nine ten eleven… all the way to the 60 second rule. Coworkers think I am crazy when they hear me counting out loud to sixty. This is a success habit. I am impatient. Counting out loud keeps me from turning the power back on too soon. It is also a good training tool because people ask what I am doing.

In our electronic age many of the controls are computer operated. I installed the pictured 200 amp motor soft start on my 3500 ton die cast machine because I wanted to free enough power to run oil heaters. Lightning strikes. About 12 times per year it hits the power grid within 5 miles of the die casting plant. Usually trips out this motor soft start computer with a fault code. Enter the 60 second rule. The soft start error happily resets if you leave it off for the 60 second rule. Also applies to the crane drives, the CNC machining centers, Gun drills, Just about every piece of equipment with an embedded computer. The residual power must drain to force a reboot. Count to 60 out loud before you call the service technician.

Counter Bore

The old addage “If the only tool you have is a hammer, every problem is a nail” Eliminating sharp edges fit into the same category “if the only tool you have is a chamfer ever corner is at a 45 angle” Imposing a one size fits all solution to a problem creates sub optimum results. This discussion is about adding counter bores to your design arsenal.

Machined 45 degree chamfers work very well when both adjacent surfaces are machined. In the picture you see a yellow 45 chamfer on the corner from the mounting surface to the bore. This was machined into the plates. On the opposite end of the bore a counter bore replaced the chamfer. This counter bore is on the corner between a unmachined face and the bore. The counter bore was created by interpolating the bore roughing cutter. This resulted in a uninterrupted cut by the fragile finish bore cutter which solved a cutter chipping problem,

Cast counter bore are used when a machined surface connect to a cast chamfer. The counter bore solve the tolerance issue and insures that the chamfer diameter is never oversize.