Cat 340D Excavator build

[crueby]

Originally Posted by ddmckee54

Chris:

When you going to introduce these guys to the shop elves?

Don

I was hoping they would stay over on the other forum with Zee!

[crueby]

Got a chance to wire up the motor and reassemble them boom, to give it a first motion test. This test was done with a 98 rpm gearmotor, I have faster and slower ones to let me dial in the max movement speed. After testing, I dont think I'd want it any slower (its on a speed control on the radio so it will do slower speeds depending on the joystick movement).


https://youtu.be/_X8LaI4TmHg


The intermittant clunking noise when the stick is coming in is the flex cable just rubbing on the edge of the slot in the boom - need to grind back the slot end just a little more. Also, I checked the force it gives, and that seems reasonable (didnt have enough hands to do that on camera, did not have the tripod handy). Overall, happy with it for a first run! Work will continue on the bucket linkages and that cylinder, also need to rig up some limit switches on the movement to keep from over-running the ends of the leadscrew. A little insulation in the boom should knock down the motor noise some too.

[Originalrob]

That’s absolutely amazing ! Can’t believe the progress your making and now I feel like I’m slacking 😂
Are you going to swap the motors out for faster ones and test ?
Looking really good

[crueby]

Hi Rob,


For the stick I am tempted to leave that motor in place, have been online looking at videos of real excavators at work, and the stick speed is about like that. If I go faster, it wont be by much. The bucket speed may need the faster motor. Guess I'll find out when more is together, and see how it all looks working as a system. I need to open the side of the boom up again anyway (sure it wont be the last time! ) to fix the cable rubbing issue and do the limit switch work. Six screws and the side panel will pop off, so that is easy (glad its not painted yet). There is enough room in the boom that I may go up a level on the gearmotor to a stronger one, I think that I have to stick with this size for the bucket motor, the stronger ones wont fit there.


Chris

[ddmckee54]

Originally Posted by crueby

I was hoping they would stay over on the other forum with Zee!

Not a chance, they're like bacteria - they spread. Or was it that they're like 2 year old's and they get into everything - never can keep that straight.

Don

[crueby]

Originally Posted by ddmckee54

Not a chance, they're like bacteria - they spread. Or was it that they're like 2 year old's and they get into everything - never can keep that straight.

Don

Sounds more like us than the shop elves!

[crueby]

Started in on the mechanisms in the stick, got the motor mounted - tight fit...






the opening for the drive cable from the motor to the cylinder:





and also drilled for the bushings at the bucket end for the linkages:

[crueby]

Some more work done on the excavator - working on the linkages from the cylinder to the bucket. The side links were milled from flat bar stock on the rotary table:





The solid link from there to the bucket is being pieced up from a thicker piece of flat bar and two round bars with slots milled in. They will be silver soldered together and then more shaping done.

[crueby]

Got the bearings and rods for the bucket links made...





and silver soldered up the blank for the end link, ready for further shaping:

[crueby]

End of the link shaped...