Another RC model side project

[crueby]

Thanks  guys! Am happy with how its coming together and  mov8ng, have had a few past attempts with other drive mechanisms that didnt work well.


 

[cnr6400]

A smart co-worker of mine used to say "the real trick in solving technical problems is to know the 16532 things that won't work, not just the one or two that will work!"    

[crueby]

A smart co-worker of mine used to say "the real trick in solving technical problems is to know the 16532 things that won't work, not just the one or two that will work!"   

Yes!  And when you find one bug, keep looking for the next one hiding behind it!

[wagnmkr]

My vote is for #2 setup as well. I guess the proof will be when it bites into Ye Olde swarf pile.

 

[bent]

I'm impressed with both motors (yes the slower motor looks better, and you might want one even slower/more torque if it's actually digging?), but even more so with the cabling and pulleys - no binding, twisting or weird motions, just smooth motion throughout.  Great job on the rigging so far!

 

[crueby]

I'm impressed with both motors (yes the slower motor looks better, and you might want one even slower/more torque if it's actually digging?), but even more so with the cabling and pulleys - no binding, twisting or weird motions, just smooth motion throughout.  Great job on the rigging so far!

 

Same motor, just two different drum diameters. They are on electronic speed controllers  also, but with the larger drum the bucket was heavy enough to spin the motor and its gearbox when the power was off!  These motors come in a variety of speeds, all same motors but different  gear ratios, very handy. They are GoBilda Yellowjacket motors, up to 12v but with max current draws in a low enough range so they dont suck the batteries down too fast. I'm  using nimh battery packs.

[crueby]

Now that the Kearsarge windlass engine is done (waiting for some replacement chain before posting final pics/videos), its back to this Ruston radio-controlled steam shovel build...

Started with making the brackets and diagonal links to go from the end of the dipper stick to the base of the bucket to hold it in place:


Also, added this square bar to the bottom of the door to give it a little extra weight to help it swing shut and latch:

Next up will be the brackets/pulleys on the dipper stick for the crowd cables...

[cnr6400]

 

[crueby]

Todays parts were the pulleys/guides for the ends of the dipper stick. The sheaves have small ball bearings so they turn easily, and the guides around the outboard ends will prevent the cable (okay, braided kevlar fishing line) from jumping off the sheave. The cables will run back up to another set on the shipper shaft (pivot for the dipper assembly), down to the base of the main boom, and back to the crowd motor in the cab. On the real shovel, they used cables also, with a chain driven winding drum at the base of the main boom. The guides were made by turning/boring a larger piece that was then cut into thirds, so the one piece made three guides.

[cnr6400]

  The pulley, cable , and guide look great Chris! Must have been confusing in the shipping department of shovel makers - "Shipper! ship that shipper assy out to the customer!"   

[crueby]

The pulley, cable , and guide look great Chris! Must have been confusing in the shipping department of shovel makers - "Shipper! ship that shipper assy out to the customer!" 

And the shipper shafts come from a Crowd-ed room... at least they wouldn't  roll away since most had square sections to hold the gears!

[Roger B]

Looking Good     

[bent]

Nice work! 

[crueby]

Thanks guys! A few more bits for the booms, then I'll go back and get the limit switch mechanisms made for the gearmotors. Also, I want to check the speed of movement on the crowd function once the cabling is on, if too fast I can swap the motor out for another one with a larger gear reduction to slow it down. This one has about 33 pounds of force, slower would be even higher, so power is not a problem! Once all the mechanical bits are done and working well, then I'll start drawing up the 3D printed parts for the cab shell.

[crueby]

This morning made up a couple new pulley sheaves for the crowd cables, where they go over the shipper shaft in the middle of the main boom. These include posts out the side to keep the dipper centered in the main boom, and ball bearings in the sheaves. Here they are with the yoke block that holds the dipper - that was made quite a while back.

Dipper and new pulleys reinstalled on the main boom, and cables reaved through. Pulling one while letting out the other the same amount (they will be wound opposite directions on the winch drum, one from each end), moves the dipper in and out nicely, so far so good.

Here are the sheaves at the base of the main boom - I need to make some tube spacers to hold them in position on the shaft

Next will be to set up the pulleys on the upper crossbar above the winch drum, then can connect it all up and try it under radio control!      Should have that done this afternoon or tomorrow. I have another event this weekend, which will interrupt things on this project for a few days.