There has been some interest on the forum recently in 'scissor lifts' for river pusher tugs' wheelhouses. I recently completed such a tug. The hull is a vac moulding from MMM, and most of the superstructure I my own design, but I used the Egrete drawings to get the wheelhouse working. It operates reasonably well, although I have just switched the radio from Giant Cod to Spektrum, and I need to adjust the servo arm to give me a full height lift.
I attach some photos of the mechanism and the finished model. This model doubles up as a rescue boat which is why I swopped the radio. My other boats use Giant Cod sets, and I thought the rescue boat needed to have separate radio system.
In the last 18 months or so I have been on river cruises on the Rhine and southern Rhone and didn't see a scissor mechanism at all. They all seemed to be of the type shown in the last photo!
Barrie