ORIGINAL: marc s
OK back on the project following some time on pressing 'other' jobs.
Now the retracts from Electron have arrived and the legs from Jet-1A, who I have to say are very helpful indeed and offer a great service.
Having heard from a few the nose gear and mains mounting plates are a little weak I added and beefed up the nose gear mounting with some extra ply formers glues to the existing and Aeropxied in place, I also added some extra ply to the rails to add some thickness to them to help achieve a stronger frame.
The Electron nose retract has the built in steering coupling, its a nicely made unit but I was struggling to work out how to hook up a servo to it without having to use wire connections which I personally hate. The Gryphon has a servo plate already fitted just forward of the tank but I decided to try a more direct linked system. I cut a piece of FR4 to fit round the main retract body and use the mounting holes as a fixing point, the FR4 plate then extended away from the main unit to allow for a servo to be mounted on it a few inches away from the steering tiller. I connected the servo to the tiller with clevis links and made sure the hole positions for the servo arm matches those of the tiller arm to avoid issues. The unit seems strong and fits nicely inside the nose section, gives positive steering, no slop and no wires to get hung up.
The wing wheel well cut-outs were not centralised on one wing, I suspect the template used to cut these moved during the routing process. Looking at the tyre options from Jet-1A I wanted to use as large a wheel as was possible, three reasons, one its better for grass to have a bigger wheel, second the ones I have seen fitted to some Gryphon's just seem a little too small, and third as I want to try to fit our new e-brakes I needed to give myself as much room as possible in the wheel hub area. I chose 75mm diameter wheels and 147mm long legs which seemed about right.
I had a friend cut me a couple of ply jigs to re-cut the wheel cut-outs, these included an 85mm diameter wheel hole to allow for the new bigger 75mm unit. A Proxxon drill, small flanged bearing and cutter through its centre was used to run round the template and re-cut the new opening.
Nose wheel is now in, mains are awaiting some 8mm dowels to connect them to the retracts. I still need to strengthen the main retract plates before final gear fitment but should have this done during the next few days.