Search results

I will take a look at the controllers on eBay. My preference would be for a control with four single axis proportional controls with spring return to center, just like the original manual controls. One or two more proportional controls might also come in handy... If I'm going to the trouble, I...

Those are lead-screw actuators. They don't satisfy my primary safety requirement of releasing the valves when power is disconnected. A lead screw actuator will hold position when power is removed, even at loads much stronger than what would stall the motor.

Environmentally sealed stepper motors may be another option, and they're a lot cheaper in the size that my first guesstimate suggests (around 280 oz-in of torque needed, I think): IP65 Rated Sealed Step Motors

Yeah, it'd cost almost as much as the whole truck. Doghead's reins idea is looking better and better...

Hmm, this looks interesting: linear voice coil motor by MotiCont I don't know about the cost or how well they're environmentally sealed, but they appear to be available at around the force and stroke length that I think is needed, they're mechanically a lot like double acting pneumatic...

If y'all have hands on experience with those large servos, can you tell me how environmentally robust they are? I'm talking about tolerance to moisture, dust, oil, vibration and sunlight, not about tree-huggy stuff. :)

Thanks, I'll look into that! I haven't measured the force needed at the likely connection point on the valve levers yet, but my seat of the pants guess is "about 5 pounds". A rotary actuator with a lever arm on the shaft might be able to do the trick. Even a plain DC motor (possibly with gear...

Is the word you were looking for "potentiometer"? Because I know all about those! I'm still hesitant to take apart the original hydraulics, but I'll keep that in mind as one of my options. It may end up being the easiest one. Well, I kind of already do that. I sit up in the gondola to operate...

Oh, by the way: I got the impression that most (all?) of the electrically-operated hydraulic directional control valves that I've seen so far just turn on or off with a solenoid valve, as opposed to the proportional control that's possible when manually operating valves like the ones on my...

Understood, but I'd prefer to leave the original hydraulic system alone. I'll look into the electromechanical valves some more to see if that changes my mind, though.

It sounds like we're thinking on the same page. My mental picture has a bank of four actuators mounted on top of the panel over the valve body, with linkages going back to the vertical levers that actuate the poppet valves. I'd want to use some sort of actuators that move freely when unpowered...

I've often thought that it would be nice to add a remote control capability to the crane controls on my M543A2 wrecker, or on the M936A1 that will replace it soon. I usually use it by myself, so it can be challenging to not be down there on the ground to maneuver the load. I've had to resort to...

Wow! That's a heck of a way to join the hobby! :beer:

Congrats on your new truck, Jeff! Is that your first M939-series?

That picture brings back fond memories of the first time I operated the crane on my M543A2. I think I was giggling, too!

Exactly! I was mad at myself for buying the useless dollies, until I realized that my total cost including transport was about what the tires on them would have cost, and the tires and wheels were direct swaps for my M543A2. There are also other components on them like the rams, pumps, air bags...

My three ordinary sea containers are all about 6" taller than the M1022 is made to work with. I don't have a link to the specifics, but I recall reading when I learned about this stuff that sea containers were originally about 6" shorter than the ones which are commonly used now. I'll try to...

Ah, I remembered something else: Other pieces missing from my units are the second drawbar that's used for moving the rear half into place by itself, and the pair of casters that's needed for doing that. I can't quite tell if they're present in the pictured one(s) above. I might be able to tell...

Those are M1022 mobilizers, not the later M1022A1 ones that have the engine-driven pumps and height adjustment. I made the mistake of buying three of them from a GL auction several years ago without previewing them and without paying enough attention to the pictures. My intention was to use them...

I noticed a few deuces listed recently. I thought they were out of the inventory, but I guess a few stragglers are still finding their way to the GL yards.