Adjustable Wrench Collar Jig

This is the description of Carl Davidson’s “Monkey Wrench Collar Tool.”  My source was the Northeast Blacksmiths Association newsletter, Spring 2012.  The following text is from the article.

“Open the jaws to the thickness of what you want to collar plus 2 times the thickness of the collar material.  With the registration stop set so your collar material is centered over the jaw opening, put the heated collar stock in place.  The squared punch must be the same width as your pieces to be collared.  Work fast, “Strike while the iron s hot.””

The page with photographs is followed by a drawn illustration page with the following text.  “Cut a piece of 1/2” sq. by 1 1/2” long and drill through the center to the size of rod* you will use for the registration rod. *5/32” used.

Cut the piece in half, drill and tap a hole for a socking screw. *6-32 used.

With a piece of scrap rod through both blocks to keep them lined up, braze them in place on the wrench jaws.  Be sure to place the front of the blocks about 1/16” in front of the bar connecting the top and bottom wrench jaw.”

In his case, he added a tang by removing part of the handle and attaching a piece of hard hole sized stock.

I haven’t had the need to collar anything since I came across the article so I haven’t actually tried this tool.  It looks like a good idea and I’ll likely try it when the opportunity arrises.  Note that the collar length must be determined to know where to set the stop so the collar is centered over the jaw opening.

Collar centered over the vise jaw opening.

Collar formed by driving down the mandrel.

Creased Hot Collars

This illustrates another version of forming hot collars.  If the project calls for a number of nearly identical collars, test collars can be made and when the precise measurements are known, a “witness” collar can be formed.

From that template, many copies can be made.  To facilitate identical bending the bend points are creased with a fuller die.  This can be done by hand with hammer on anvil, treadle hammer, fly press, etc.  Presumably, a jig could be set up to make the process even more precise.

Metal bends where it is thinnest or hottest.  This is an example of exploiting both tendencies through selective torch heating at the crease.

I first saw an example of these collars lying on a platen table at Flicker Forge alongside the die which made the crease.

Fuller creases at bend points.

Forging Hot Collars

I did a web search for the Francis Whitaker hot collar formula.  It is illustrated in his “Blacksmith’s Cookbook” and I’me heard many people recite it.  It wasn’t so easy to find on the web so I decided to do some SketchUp illustrations and post them the the 3D Warehouse.  When I tried this morning I got the message that “The service is not available.  Try again later.”  So, I plan to do that.

In the meantime I’ll post images of some illustrations I drew.  The show the Whitaker formula and the sequence of steps in the forming process.

Bill Fugate published the formula in the Pittsburgh Area Artist-Blacksmith Association newsletter in July 2010.

http://paaba.net/Projects/BFCollar.pdf 

Carl Davidson published a nice article in the Northeast Blacksmith’s Association Spring 2012 newsletter showing how to modify and Engineer’s wrench into a neat adjustable collar making tool.  I couldn’t find a link to it just now.

Next time I’ll illustrate another way to make collars which I learned on a visit to Flicker Forge.

The Francis Whitaker Collar Formula 

Starting the collar forming after calculating the collar length and beveling the ends.  Francis suggested finding the CL then moving over one half the width of the waterfall to be collared to start the first bend.  This should get the lap pretty well centered.

A mockup of the workpiece can serve as a mandrel to be used with the vise. 

The collar can be finished on the mandrel and opened to fit or the final two bends closed over on the workpiece.

Sometimes is most efficient to form a batch of collars on a mandrel and open them up so they can later be fitted and closed on the workpiece with torch heat.