90 ton 1/14 metal excavator scratch build w/embedded PC

[SteinHDan]

Hi Machfab!

> Will the gamepad/pc controller give you proportional control of the gearmotors or just on/off control?

The gamepad gives full proportional control for all the gear motors, including the track motors. I'm using the front analog triggers for the track motors, and I use the two front buttons to reverse the track directions. The swing, boom, stick and bucket controls are on the two joysticks and equal to running a normal excavator (ISO-mode).



This particular gamepad (the Logitech F710) doesn't stand back in sensitivity or accuracy in control from any of my normal RC transmitters. But most cheaper gamepads have less accurate analog control and also a larger deadspace in the middle / neutral position.

I would say the pros and cons VS a normal RC transmitter:
- Pros: Smaller, cheaper, 2 analog joysticks, 2 analog triggers, 1 digital four-directional pad and 10 digital buttons
- Cons: Short range (10m), no telemetry


Machfab, are you by any chance affiliated with http://machfabengineering.co.uk/ ? I just asking, because it would be interesting to get a quote on how much it would cost to get all the aluminum parts cut at a professional shop. I'd buy a set myself if someone could make it (depending on the price of course).


Best regards,
Stein :-)

[Machfab]

Originally Posted by SteinHDan

Hi Machfab!

> Will the gamepad/pc controller give you proportional control of the gearmotors or just on/off control?

The gamepad gives full proportional control for all the gear motors, including the track motors. I'm using the front analog triggers for the track motors, and I use the two front buttons to reverse the track directions. The swing, boom, stick and bucket controls are on the two joysticks and equal to running a normal excavator (ISO-mode).



This particular gamepad (the Logitech F710) doesn't stand back in sensitivity or accuracy in control from any of my normal RC transmitters. But most cheaper gamepads have less accurate analog control and also a larger deadspace in the middle / neutral position.

I would say the pros and cons VS a normal RC transmitter:
- Pros: Smaller, cheaper, 2 analog joysticks, 2 analog triggers, 1 digital four-directional pad and 10 digital buttons
- Cons: Short range (10m), no telemetry


Machfab, are you by any chance affiliated with http://machfabengineering.co.uk/ ? I just asking, because it would be interesting to get a quote on how much it would cost to get all the aluminum parts cut at a professional shop. I'd buy a set myself if someone could make it (depending on the price of course).


Best regards,
Stein :-)

No, not them. Just own a machine shop here in the US.
Also a user of Fusion360
Plan to do this build. Very nice! Thanks

[SteinHDan]

I've added some bronze self-lubricating bearings to the bucket linkage. I don't think they were really required, and it goes against one of the goals of this project, to keep it simple, but it just pains me to know that there is a load-bearing joint without any form of bearing in it. So it had to be done! :-)













The parts:
- Clips: HSP 02053 Body Clip
- Bearings: 8 x 10 x 12 oilless bronze bearing

[SteinHDan]

3D printed the ABS plastic parts that go in between the aluminum sides in the boom and stick sandwiches. I also re-did the boom sides in 3mm aluminum, as by mistake I made them 6mm thick the first time, which made me have to add 3mm spacers in many other places.

The ABS parts are printed with 16% infill, except the mounts for the stick and bucket cylinders, which are printed with 25% infill.

The filament used is this one:
- eSUN ABS 1.75mm Gold

This filament's color isn't really that close to the Caterpillar yellow, but it's the closest that I've found. I know there are companies that do custom colors, like www.plastic2print.com, but those are quite expensive and have order quantity minimums.

So if anyone of you guys know of a yellow ABS filament that is a closer match to the Caterpillar yellow, I'd very much like to hear about that.