Tractor backhoe - homemade

[4570Man]

Yours is the best one man fab job I’ve ever seen. I see excellent work at the metal fab shop all the time, but they had a welder, a machinist a parts cutter, and working from someone else drawings. To do it all yourself is more impressive.

 

[BFreaky]

Working...

Done

 

[Rustyiron]

You are my hero
Looking forward to following your project.

 

[Kyle_in_Tex]

What kind of steel is that? I see the chips coming off are blue.

The bluer the chips, typifies the harder the steel.

How did you measure to keep the center bore in the same datum of the 2 end pins?

I'm making some parts at work made from Hastelloy X. This is the material the Germans wish they had in WWII for their jet engines on the ME 262. It takes really high heat loads. Along with Inconel.

 

[BFreaky]

It's st52.3 J2+N construction steel. 2-nd picture shows the solution. First I finished the big hole for the cylinder and then aligned the surfaces to get a perfect square 50x50 mm. Then i just had to make an X on both of them and drilled a hole.

 

[Renze]

It's st52.3 J2+N construction steel.

You dont win when using a higher grade of steel. Once welded, the fatigue life of all steels is more or less the same, only the Charpy impact energy will determin how fast a microcrack will grow.

High strength steel is only beneficial when the amount of load cycles in use, are low. Telescopic crane booms are bent into two U shapes that are welded together, so the weld is in the neutral axis. With diggers the amount of load cycles per hour is much more, so theres no benefit in S690 or higher.

 

[BFreaky]

The machine will have hardened pins, replaceable bushings and every important part will have hardened steel such as Hardox cutting edges etc. General construction parts will be st 52.3 because it's just fine for this purpose. I was thinking about using Domex or Strenx on the boom sections but havent decided yet...

 

[sixdogs]

The quality, design and engineering of all this boggles the mind. What perfection.

 

[dragoneggs]

The quality, design and engineering of all this boggles the mind. What perfection.

Yeah I find myself doing projects like this late in the evening... then I wake up and realize I need to clean off my workbench in the morning and figure out what projects have been stalled and covered up with others. :laughing:

 

[BFreaky]

Made some cylinder rod ends...

 

[Kyle_in_Tex]

Can't imagine the amount of work, time and money......

Were you able to find some heavy wall tubing to make those, or from solid round bar stock?

 

[BFreaky]

It's made from round tube...got no problems with materials, everything is available you just have to determine optimal size..

 

[Kyle_in_Tex]

Your English is better than mine.

Glad you were able to design for tubing. I used to have to help set up a 10 meter long trepanning machine and another honing machine for tubing. We would typically bore about 4-8mm out of the internal diameter ID on the trepanner and then hone for finish size and smoothness. Usually in the 175mm zone, +/- about 40mm depending on size of oil field operation.

pokračovať !

(I honestly don't remember your native language)....

 

[BFreaky]

My native is Croatian. What you wrote is a Slovakian word. I only take 2 mm off inside and 1 mm on the outer diameter to get it right

 

[Kyle_in_Tex]

My native is Croatian. What you wrote is a Slovakian word. I only take 2 mm off inside and 1 mm on the outer diameter to get it right

Sorry about that.

My friend at work is a young man who's parents were missionaries in Croatia. He grew up over there and speaks the language "OK" he says. He's going back to Croatia soon to visit old school friends he made when he was young. He is now an aeronautical engineer working as a mechanical engineer.

 

[BFreaky]

Finally got two small cylinders for the rotation...

 

[texasranger556]

Finally got two small cylinders for the rotation...

You built your own cylinders!?

 

[BFreaky]

On the rk 525 yes. This time I got all the new cylinders, factory made. It saves me alot of time. None of them have rod ends so I'm gonna make and weld those in place

 

[texasranger556]

Ahh, that makes more sense. I thought you may have built your own cylinders on a lathe given your skill and desire.

Looking forward to the rest of the build!

 

[BFreaky]

I made a few cylinders...but you can't save much money compared to the new ones because of the time it takes to build one. If I had a cnc lathe it would be a different story.