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Tuesday, February 12, 2013

Weights and Measures Continued

At this point on the coin balance I have one major thing remaining, the cross arm.  The larger balance needs both the cross arm and a set of hooks to hang the pan from the chains.  I started working on the chain hooks next.  (Anything to postpone the detail work on the cross arm).

I had a rough idea in my head of how I wanted the hooks to look. I wanted squared up wires twisted and shaped a little more decorative to add a little character.  I started mocking up a piece to see how a copper hook would look at the end of the brass chain.  The basic process was something I learned blacksmithing.  Same concept, but smaller scale.  The copper was all simply worked cold though.

  

A few twists and the mock-up is about done.  I like the overall look  of the squared off wire.  Seems to catch the light nicely and adds a little character without too much extra work.


Next step, cut the "real" pieces to length.  I cut them to length and then filed the ends even in an attempt to keep the weight about the same for all the pieces.  On the following image on the right you an see that as I square up the pieces the length of the material is drawn out a bit.  Since I wanted all the hooks to look similar as possible I made sure to perform each step on each piece all at the same time.  I drew them all out and squared them up and compared the pieces.  Added the hooks and compared... etc.

 

Hook ends added to each piece and compared again.

 

The top piece is the mock-up I used as a guide for the other pieces.  What you don't see here is the two pieces I jacked up.  I tried to fix them and decided to toss them and make a couple more to match.  Wanted a symmetrical even look and feel for all hooks.


Finished hooks.


Next step... the arms?  Nope.  The weights.  Don't know why I'm afraid of starting the cross arms, but oh well, I'll keep being a well-practiced procrastinator.

The cut out one circle of the scrap brass I had.  I weighed it on a digital scale to get an approximate weight.  Based on the large circle I had I did some math to figure out the rough diameter I would need to get a 1/10th ounce piece.  I roughed out one and yup, it was about 1/10th ounce.  I then cut 9 more pieces the same size.  I figured if the brass was all the same thickness (roughly) and the size of the circles all matched exactly and they total weight of all 10 circles was one ounce each one would be 1/10th of an ounce.  My scale is not very precise so I had to take this approach to get a decent set of 1/10th ounce pieces.


OK, now I can't put this off any longer... I had to start the cross arms.  I started with the smaller coin balance.  My intent was to make a solid arm for the smaller scale and a folding arm for the larger scale.  I started with copper wire from Home Depot.  I believe it was 8 gauge.  I squared it up and fish tailed each end a bit.  i wanted the fish tail to drift to one side to allow for a cosmetic hook device to hang from.

 

The basic shape above was done on my large anvil with a small German smithing hammer I use for blacksmithing.  Now that I got it to this point the rest of the work was done with metal files.  I used small pin files to shape a decorative end to it and then punched and drilled the holes.


 

Now for the next FAIL in the project.  As I said, I had intended the cross arm to be a single piece.  With that in mind I planned on drilling some holes to mount the brass arrow.  No great surprise that my use of power tools back fired on me.  I tried to drill the piece with a power hand drill and I broke the bit.  I tried to dirll again next to the hole and it came out the side.  UGH!  Can't use the piece.  As a quick remedy I cut out the center section and plan to make the coin balance a folding pieces as well.

 

Newly chopped up piece.  At this point I was so ticked off I simply put it away.  I'll clean up the rest with files and next time I'll either borrow a drill press or hand drill it.