Food for thought for those finding their Gong mast a bit soft with their L or XL wing, here is a way to get a more rigid feel (it is not mine).
Gong mast: 109.5 x 14.7mm
Axis mast: 119.1 x 18.9mm
Pict 3: once your fuse has been milled by 9.5mm in length and 2 x 2.1mm in width, you cannot go back anymore.
[Credit to Dave K]: You have to adjust the new mast position slightly to avoid conflicting overlap with the existing M6 bolt tap locations in the fuselage. I had the machinist line up the forward Axis M8 bolt location to the existing forward M6 bolt tap in the fuselage. It moves the new mast about 1cm forward of the current mast location. No biggie, and it works great.
Gong needs a better connection from their fuselage to mast. That’s where a huge amount of the issues are. I’ve had the same problem with my slingclone setup. I then made some decent adaptors and all the issues disappeared.
The wall thickness (+1mm per wall for Axis) is a part of the explanation, also the choice of screw sections that hold everything in place. On the above example, we can see that Axis has chosen 2x M8 screws, with Gong : some people use only 2 x M6 screws. When you do the screw section ratio, you get 1.78 so you have nearly 80% more material on the Axis solution. Some people use 3 x M6, but it is still 15% material under Axis.
With a good adaptor, the screws just about become negligible as they are just being used for fasteners. Ultimately you want the fuse wedging into the mast and visa versa to just about create a single structure…
