Looking for a specialized wrench

The draw bar on my "new" Pratt & Whitney 3C mill has a big nut on the end for tightening. It is big....1+11/16ths and I am looking for a wrench to use on it. What I envision is not a big old heavy wrench but one made of flat steel with a round head and the 6 point openning....something relatively light-weight. Something like the one in this pic but hopefully just one-ended, but I am having trouble finding what I am looking for. Ot looking fir a socket. Anyone have any suggestions?

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Chrome sockets get the abrasive chop saw. Even the impact socket might be best abrasive cut, or parted on the lathe. I wouldn't use my
bandsaw blade on one.
When thinking cheap I was thinking harbor freight. I've machined some of those and there are definite hard spots mixed in them.
 
You have several choices. Do not forget to include a generous clearance across the flats, a minimum of .01"

If you have a NC mill program the hex including some corner reliefs for the milling tool radius.

If a manual machine use a rotary table or indexer and mill the hex including some corner reliefs for the tool radius.

Have a shop with a NC abrasive waterjet cut the hex for you including some corner reliefs for the tool radius. This will be a small radius however.

If cost is no object a WEDM shop will knock this out with less then a .015" radius in the corners.

This is as simple as machine work gets.

If all of the above are too expensive or you are not capable of performing the operations yourself buy a 1 11/16" wrench for $25.00 and cut one end off. https://www.jegs.com/i/Sunex/344/95...MIoMrM47fr3QIVhp-zCh06Iwf0EAQYAiABEgKQ2fD_BwE
 
Discodan,
Went thru this when I got my first horizontal mill. Big wrenches required. I found very good quality US made wrenches at a local steam engine show. There were literally thousands to pick from. Seems every table in the swap meet/vendor area had tables and buckets loaded with them.
I'd google thresher, steam engine, and swap meets within driving distance of you. Bring the drawbar with you to verify fit! You can easily mill the flats for a custom fit. I wound up doing that with one of the wrenches I found. A beautiful Williams brand wrench but it was just a hair too tight. Great fit and size overall. Quick milling set up and it fit perfect. Not bad for about $4 if I remember right.

I would stay away from sockets. Repeated loosening and tightening of the drawbar will eventually round off the corners.
 
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gi_984, that is a good idea. I am headed to fall Carlisle tomorrow so I will be taking a tape measure with me. If I don't find something there I will keep my eyes open for a steam show. I also started the process of making one but haven't had much time so far.
 
Drawing the outline on a piece of cardboard makes a very quick go/no go gauge to quickly weed out possible wrenches. When I found one that was close I'd pull out the actual arbor out of my backpack to check fit.

I always carry a small backpack to carry purchases when attend the swap meets at the tractor/steam engine shows. Always seem to find machining & shop related goodies. Some dirt cheap.
 
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Why can't you mill down the flats on the nut to a common wrench size? That's what I did on a AXA tool post for my SB 9A so the tail stock wrench would also fit the TP.
 
This machine has survived for 75 years without being hacked on and I want to keep it that way. Finding a solution isn't that difficult, I just had a vision of what I wanted in my head. I may end up with something else.
 
"Why can't you mill down the flats on the nut to a common wrench size?"
Because of the necessary torque required to secure BIG end mill holders and other tooling. Lot of force. The drawbars on the average horizontal mill are big for a reason.
 
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