First one of these I have come across too.

Mine doesn't have the spoke dog.

http://www.datamp.org/patents/displayPatent.php?pn=476629&id=24941

Over the years, about half the Gendron wrenches I've seen don't have the spoke grip.

I've managed to find one of each.

Mike

What is the spoke dog?  Is it the groove in the top jaw?  What's it for? 

Thanks.
Al

Bicycle spokes.
I have several and none with the dog.

Al, this is a Gendron bicycle wrench.  Gendron was a bicycle manufacturer.  Some of these wrenches had a little serrated piece on the back side of the wrench that was used to tighten the wheel spokes.

This was on the side that is usually used as a hammer.

Maybe someone can post a picture.  I'm not home or I would.

Mike

for pictures of both types, go to the DATAMP link that HeelSpur put on.

and above the picture of the patent, you will see  1-2  click on 2 and a picture of both
will be shown.

Thanks for the explanation.  I think I see - it's the back side, hammer side that is the spoke turner.  I'll check the DATAMP picture - right now the server is down.
I didn't realize that was a bicycle wrench and never heard of Gendron before.  I'll have to look that up later , too.

Thanks.
Al.

This is a fairly tough repair.
  I have done it before though.
The damage happened when someone tried to crack loose a frozen bolt that was too big for the tool. The main bean has been bent not too far under the head.

  The trick will be using a very large bench vise, with padded jaws (I use aluminum roadsign material)
  Clamp it just under the bend. Face the narrow end of the jaw toward the back of the vise. That means the hammer part will be facing front.
Use the very middle of the vise jaws.

  Really reel down on the vise, it will want to slip.

  Now take at least a 2 pound hand sledge and clobber the hammer head part of the jaw. Center blow, center of the hammer head, straight toward the back of the vise.
It will take several huge blows.

But in the end, the beam will straighten back out, and you will be able to fully close the wrench again.
    yours Scott