For the past year, I have been working on this MOC, making very slow progress mostly due to a lack of time. About a month ago, I finally reached the point where I considered it finished. It's not perfect and many things can be improved, but I am happy with the current state. Enough to finally make some pictures and a video.
The MOC is based on the Manitou TMT 25S. It is a hydraulic forklift, one that hooks on back of trucks, but uses an unusual design. A picture from the original:
It also combines some interesting hydraulic functions which I tried to carry over to my model.
In the end, this is the list of functions I managed to implement:
Manual steering, control placed at the back, behind the cabin - rear wheel goes 360 degree.
Pneumatic compressor using an M motor and two pumps
Electric switch to control the compressor
Pneumatic functions for:
Boom lateral adjustment
Initially, my intent was to have an auto switch for the compressor. However, after many trials, I could not calibrate it properly so that enough pressure remained in the circuit to control all functions properly. The switch would not always return in position when the pressure was dropping, making some functions such as raising the boom unusable. So I replaced the assembly with a manual switch which can easily be controlled when air is required.
To smooth out the functions, I used an air tank which is hidden below the control valves in the back.
Overall, the functions are working well. The main issue is the control of the fork, which really needs better smoother valves to have finer control. Also, since it is pneumatic, It does not maintain its position when elevating or lowering the boom. I could not find a way to do that while keeping the boom extension which is required.
So here are the video and pictures. I hope you enjoy it.
More pictures are visible on the BrickSafe folder: https://bricksafe.com/pages/Minique85/manitou-tmt-25s