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Looking for a specialized wrench

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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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#3
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?
Pretty easy to make on a milling machine. First, drill a small hole (~1/8") at each corner of the hex for clearance, and then mill out the hex shape. Shape the outside dimensions any way you want.
 
#4
Or you could have somebody wire EDM the hex, or even water jet cut the whole shape out of plate. All they need is a dimensioned drawing to program it.
 
#5
Pretty easy to make on a milling machine. First, drill a small hole (~1/8") at each corner of the hex for clearance, and then mill out the hex shape. Shape the outside dimensions any way you want.
I had not thought of that but I guess I could put my new mill to use!! Thanks for the idea.
 
#6
The wrench could easily be made on a mill with an RT. Cut a disk to the O.D. Set the center of the wrench opening at the center of the RT. Move the table over to cut one flat and rotate 60º to cut the next. The start and end points of the cuts could be marked with layout fluid or you can calculate where they will be and cut by the dial or DRO. You could also pre-drill the corners. Clean up the corners or mill a relief pocket to finish Weld a handle on to complete.

No RT? Drill the center hole for as large a bolt and nut as you can. Tighten the bolt & nut. Place the nut in your milling vise a stop to locate it and clamp the woerk to prevent rotation. Cut two opposite flats. Rotate 60º and cut two more. Another rotation and cut the final two. Clean up as described before and weld a handle on to complete.
 
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#7
Why not just make it an open end wrench?
 
#8
Hi Guys,

Drill holes in each of the sides and use a bar !
 
#9
Building one is great. I did that for my quick change tool post wrench. Nice and short for it's wrench size. Hangs on a hook above my lathe
within easy reach.
Other thing you could do is buy a cheap impact socket and cut the end off and weld a handle on.
 
#10
Other thing you could do is buy a cheap impact socket and cut the end off and weld a handle on.[/QUOTE said:
I worked nights as a diesel mechanic for a few years before moving to days. Snap-On sold a specialty wrench for removing the bolts on the fan hub or the water pump (can't remember which) on a Cummins engine. Well... rather than pay the high dollar for the wrench, I would make one. Bought a 3/4" Snap-On socket and one night took it to the machine shop (machinists all gone home by this time) and proceeded to cut it off in the horizontal band saw. I have to say, Snap-On has good chrome... oh it eventually cut it off, along with taking all the teeth off the band saw blade. Went back to the truck shop, fashioned the handle, welded it to the cut off socket and had me a clone Snap-On Cummins tool.

Point is...... don't cut off chrome sockets on a band saw.
Next day... I was told... the machine shop foreman was over at the truck shop lookin' for whoever it was that left all the chrome shavings in the bandsaw. Nobody knew anything.
 
#11
Dan , I'll check my drawers .
 
#12
I've got a perfect piece of scrap steel that I will use to make my own and hone my fab skills. By the way, I made my first chips with it yesterday on a test piece of aluminum. This 76 (?) year old machine is tight and smooth and quiet. Here is the link. Click on Watch on Facebook.

 
#13
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.
 
#14
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
 
#15
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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#16
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.
 
#17
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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#18
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.
 
#19
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.
 
#20
"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.
 
#21
It doesn't take any more torque to secure a big end mill holder than it does for a small one. Besides that, the size of the flats has nothing to do with the torque. It would be easier to find a commercial made 1-1/2" box end wrench instead of 1-11/16".
 
#22
I think Keith Fenner did a video on making just they sort of spanner you want. I'd bribe a high school kid with some free burgers to make a CAD file for me and send out to get waterjet cut or make one using whatever tools you have to hand. At a minimum you'd need a drill, a hacksaw and a file but might take a while.
 
#23
Went to fall Carlisle today and found my 1-11/16ths wrench in the second stall I visited. $3.50. Saw another I liked better later but he wanted too much. I really wanted a box end wrench but I will live with this one while I convert to R8 collets and a new drawbar.
 

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#24
Looks good. Love going to the swap meets at these shows. Going to a local one tomorrow to see what I can find.
 
#25
Looks good. Love going to the swap meets at these shows. Going to a local one tomorrow to see what I can find.
I blew it on a set of R8 collets. Saw them early and didnt want to carry them around and the whole box was gone when I went back. Didn't think machine tools were a hit commodity at a car flea market. But it when you see it!!
 
#26
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?
I would try getting a deep 1 11/16" impact socket and weld a flat bar handle to the od of the non drive end and then cut off as much of the socket that you would like. Using a deep socket leaves you with a usable socket after you have cut off the amount you want for your wrench. Impact sockets are easier to weld onto the chrome plated standard sockets.
 
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