Tractor backhoe - homemade

[JDonly]

the pins are in shear, the bushings are loaded in compression. your shear stress is .577 X radial load (lbs) / pin cross sectional area (square inches) you want the yield strength of whatever your pins are made from to be atleast 2 - 5 times greater than this. Because it is subject to repetitive loading (fatigue) it should be 10X or more.

Uh, Wut?

 

[Kyle_in_Tex]

The only pin I've made for my post hole digger pivot pin, was made from 17-4 Stainless, (Type 630 for you international folks). I drilled it and crossdrilled it for grease, then heat treated it to H900 fahrenheit about HRc 44 hardness. It is VERY tough stuff. But it doesn't have the super hard rockwell you guys are mentioning.
175,000 psi yield, 190,000 psi Tensile strength

It doesn't get used much, I can't put down pressure on it. It just pulls it out of the ground and hangs from it.

 

[unclebilly]

17-4 at H900 should be around HRC 50 and about 150ksi yield off the top of my head That will be awesome, provided it s not too brittle. I work with 17-4 all the time for down hole tools.

 

[pickstock]

im going to ignore posts about pins... =)

FIRSTLY WOW!!!

secondly did you do these from plans or design your own?
Any chance i could get a copy? i need one of these and not going to pay the 2500 to hire one

 

[pickstock]

im going to ignore posts about pins... =)

FIRSTLY WOW!!!

secondly did you do these from plans or design your own?
Any chance i could get a copy? i need one of these and not going to pay the 2500 to hire one

 

[BFreaky]

I made the whole thing all by myself, all the planing, parts, drawnings, everything. Are you sure you wan't to get into this?

 

[pickstock]

if your willing to share yes
The biggest problem i would have is cutting the material as i only have accsess to a hand oxy set but **** in the long run this is the way to go.
The world needs more people like you

 

[BFreaky]

Without the CNC cutter this project is almost impossible...it would take you a year to do it..
Today I connected the boom and bucket cylinders, so here's how it looks:

 

[pickstock]

wow, i might look into getting everything laser cut and ill weld it together.

would make a better job than an oxy and a file =P

 

[pickstock]

wow, i might look into getting everything laser cut and ill weld it together.

would make a better job than an oxy and a file =P