Author Topic: Elmer's #29 Mine Engine question  (Read 551 times)

Offline Sky King

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Elmer's #29 Mine Engine question
« on: April 20, 2019, 02:51:31 PM »
What is the best way to make these pieces???
I have not tried making them one piece, I did try soft soldering a boss on and  it pulled loose when I tightened the set screw. Have had no luck with silver soldering one either.  So what would be the process to make them from bar stock???
Clausing 8520
EMCO Maximat V10-P
Craftsman 6"

Offline cnr6400

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Re: Elmer's #29 Mine Engine question
« Reply #1 on: April 20, 2019, 03:14:52 PM »
I'd suggest turning a boss on the end of a faced short steel bar in the lathe, and bore the ID of the boss. The bar needs to have a diameter a little more than twice the distance from centre to the end of the arm of course. 1.125" dia stock or larger would work for the arm in the drawing. Then on the mill, with the rod set vertically, cut most of the disc away leaving the boss and the arm shape, and drill the end hole for the pin. After that you could slice the arm off the end of the rod with a slitting saw. The pin could then be made in the lathe and silver soldered in to the arm, and the setscrew hole drilled and tapped.

For this type of soldered-in pin, I usually make them with a small thin head, to keep the pin in place easier during soldering. After the soldering, the head can be left on if there's room, or filed away if there isn't room.

Hope these ideas help.
« Last Edit: April 20, 2019, 03:18:36 PM by cnr6400 »

Offline kvom

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Re: Elmer's #29 Mine Engine question
« Reply #2 on: April 20, 2019, 03:16:46 PM »
Rotary table for the boss.  The other end can use rotab or filling button.  I have seen where people place the part on a centered rod and rotate it by hand while milling;  somewhat dangerous but if you're careful...

Another option is to layout the part on some round stock with the boss centered, and drill/turn it.  That would require a larger piece of stock.

Offline Sky King

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Re: Elmer's #29 Mine Engine question
« Reply #3 on: April 21, 2019, 03:10:27 PM »
Thanks for the advice,,,
What I ended up doing was,,,since my vice is such a pain to setup I did not want to use the RT. I found a piece of 7/16"x1/2" bar stock that I centered  in the 4 jaw at the location of the boss, I drilled the boss hole and then turned it to the correct diameter. I then parted it off and finished it up on the mill and filing. I think next time I will use a slitting saw instead of parting it off.
Clausing 8520
EMCO Maximat V10-P
Craftsman 6"

Offline kev

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Re: Elmer's #29 Mine Engine question
« Reply #4 on: April 21, 2019, 04:40:26 PM »
thats how I do it skyking, cant be bothered setting up an RT for such a small part, few minutes with some files and buttons and its all done.

Must admit because we all like machining sometimes we forget that just a few minutes with a file saves a lot of unnecessary setting up and milling but each to their own its only a hobby after all.

btw im also currently making a mine engine along with the grasshopper and tall vertical all in parallel  :)