Looking for someone to finish two parts for my 1910 Mitchell

[99Panhard]

I'm a long time participant in the Antique Machinery sub forum and I've had very good luck doing business with forum members. Here's the issue...
I have made two pieces for the rear hubs of the car I'm restoring...they are cross shaped and have a 1-1/8 square hole in the center with 1/2" radius corners. The material is 4140 and the thickness is slightly more than an inch. I could mill these but, frankly, making them was such az long process that I'm hesitant to ruin them on the last, and most demanding step when it seems (at least as I understand it) that EDM is nearly a foolproof way to do it and not particularly difficult if you have the equipment and expertise. I can furnish one of the original pieces as a guide (I only have one) as well as photos of the pieces as they are now. The tolerances are not demanding...an accuracy of +/- .005 would probably be fine but if you came close to the hole in the original I know they would fit.

I confess to knowing next to nothing about EDM beyond the basic theory and I realize that not many shops are interested in a small one-off job like this but I've had no luck finding anyone local to do it and would prefer that it be done by a professional. If you have any questions I can be reached via a PM and if you are interested in what I'm doing search on my forum name, 99Panhard.

Thanks,

Joe Puleo

 

[Dan from Oakland]

Joe- with a 1/2" radius in the corners I don't see a need to EDM these as they would be easily CNC milled with that large a radius. Only reason I can see to EDM them is if they were heat treated 1st and you wanted to avoid any heat treat distortion. Just a thought for you to consider.

 

[99Panhard]

The truth is I care how it's done. I don't have CNC. I did mill a trial lhole but I did that with a dial indicator on the table of the mill. It was a very tedious process and one slip or inattention and the part would be ruined. I do my milling on a Brown & Sharpe 2H horizontal with a vertical head. It's the second newest machine in my shop at about 1935! I will gladly defer to anyone who knows more about this than I do but I know as little about CNC as I do about EDM.

 

[99Panhard]

I don't have a drawing...though perhaps I could make one. I'll gather up the material and post some pictures.

 

[99Panhard]

Some photos...

The part in its current state mounted on a fixture I made to mill it. I stopped on this about 3 months ago to work on my house...

Also, the part mounted in the hub. The axles have square ends and this is what dr4ives the rear wheels. It's all held together by the hub caps (which I also made). The 1" hole with a kewyay was there for the fixture I used to tun them. The keyway is placed to correspond to one of the corners of the square. These were milled out of slugs of round 4140...I think they started out at about 13 Lbs and finished up at about 4.

One of the parts I made with the intact original...as you can see, the original holes were not that precise. I wouldn't mind getting them better than the original but with a 1.125 square axle shaft there isn't a huge amount of stress here.

 

[bob]

Ideal job for wire, surprised nobody has offered to do it. If I were local would do it no problem and not much money ,I am not so won't.
Bob