Dyne's LD-F1 (D-O concept) build

[kresty]

Punting sounds like a good plan

Though it is probably a bit annoying that the battery is probably where the servo'd need to go.

Browsing I found this picture...

Looking at the upper hydraulic ram that lifts the top arm of the crane, there's a short lever arm. When the arm's about 1/2 way extended, that lever arm would be perpendicular to the ram. It also doesn't get very far from that.

Of course a hydraulic ram can apply a lot of effort. A similar position for your model might be if the middle section were your lid, and the top hinge was your pivot point, then a lever arm forward of that pivot point might work. But unless it's really far from the pivot point, it's going to have poor leverage.

Another picture I stumbled upon.


Note how the piston is kind of far along the arm. That helps the leverage. Since it's hand pumped unlike the crane, that's important (though it'll require more pumping). Also notice that when the engine hoist is in the working position (parallel to the ground), the ram is nearly 90 degrees to the arm. That's actually kind of what I was thinking when first considering your problem - you really need it mounted vertically (but there's not enough room I'm pretty sure).

Anyway, you're build's looking good! Impressive pace you're setting.