Nauman Sinus Punch

I came across these tools which haven’t been called for in quite a while, but when the opportunity arises they are really handy.  I learned this technique from Dan Nauman at a BAM meeting several years ago.  When I got home I made my own tools.  Three were made from coil spring and one was an Allen wrench as I recall.

The pattern I tested came from Dan’s demonstration.  The printed copy is glued to the sheet metal with rubber cement.  I had an ash log just the right height for working - about vise top height.  As soon as the tools were made I tried them out.

I have forgotten the gauge of sheet I experimented with but I think it was 16 gauge and the holes punched easily and cleanly with the slugs sinking into the end-grain surface.  I thought it was a lot faster and more fun than drilling if there were a lot of holes to make.  

The shape of the cutting edge of the punches is important as well as their sharpness.  I don’t know the upper limit of metal thickness for this technique but I’g going to guess that above 14 gauge it would be better to go to a mechanical punch or to drill.

See Dan’s work here:

http://bighornforge.wordpress.com

That’s a Swell Hole

For the past couple of weeks, besides trying to get the lawn to recover after the terrible hot and dry summer, I’ve been finishing a chandelier. I’ve never made one of this style before and have found it to be interesting and challenging. At this point the frame and pendant elements have been constructed and I’m just working on finishing details.

This detail, if not trivial, is at least a very small one. In my opinion I still think it is worth considering and in other cases can create a much more striking visual detail.

In this design the power cord traverses most of the distance between the ceiling canopy and the candelabra pendant inside a tube with rings at each end instead of winding through the more common vernacular chain. After making the rings from 5/16” round and flattening 1” of the tube ends with the hydraulic press, I sunk a center punch mark and then drilled a pilot hole. Working over a narrow vise opening I heated the hole perimeter with the torch and used a handled opening punch to enlarge the hole so that the 5/16” ring could pass through and swing easily. That process necessarily creates the slight bulges along the edges of the flattened area.

It may take a blacksmith to notice a change this subtle but an accumulation of such little details in the design can eventually add up to interesting.

http://www.persimmonforge.com/