i am not sure what you mean by the mounting plate design but as far as i know the mounting plate design is for the Spade and ZII come with the single mount glued into the foam. I don't think EPP is strong enough to hold the mount so you need a base plate to mount it. Secondly the height of the mount is limited so it would be the same thing as mounting it on the top as you have to carve out all the the foam from the top to have some space for the motor if you are mounting the motor belly forward.
ZII (1.3 GHZ) (40.1 km), Hercules Pusher (1.3 GHZ) (23.8 km), Sky Hunter (1.3 GHZ) (19.9 km), Deep Reaper (1.2 GHZ) (13.4 km), Penguin (1.2 GHZ) (10.5 km), ZIII (1.3 GHZ), Titan (1.3 GHZ) (LOS low altitude), BobCat pusher (5.8 GHZ) (LOS), Assassin 5.8 Ghz)
DJI Flamewheel 450 (1.3 GHZ), DART 400 1.3 GHZ, DART 250 5.8 GHZ
I suppose without having both the center section and the mounting supplies in front of me I can't accurately mock it up. I see the same thing as you on the Ritewing designs, but I think while the metal flat plate portion of their mount is embedded in the foam, the vertical section is shorter than way CTH provides. But yeah I don't have it here so not much more I can say.
Ok here we go, our own guy Ruben did a build video for his wings and demonstrates how to remove some foam from in front of the mount to put the motor bell forward. His motor mount is wider than the metal part of the CTH but imagine the laminate tile and metal L-shaped mount are one piece. I assume Lee is still providing the white hard square tile with his kits.
About 26min in
http://youtu.be/T-swA5thx8U
Viper: Since this is my first CTH plane I think I'm going to lay everything out beforehand and follow Lee's recommendations. If the CG is way off or I get adventurous I can always revisit the motor mount issue later. There's a time and a place for experiments but I don't think this is it.
I'm taking my time on the DRXL/Gladiator. I'm going to start laminating tonight but I've been getting things ready for my motor mount as well. Lee's build video only briefly mentions it. He says that in his builds only one screw goes all the way through to the other formica plate. To me that doesn't seem very sturdy, especially if using machine screws with small threads to grip the formica and foam... But, he's the expert... So, I'm curious, how have you guys done it and how did it work out for you?
I installed four screws all the way through both the plates, with lock nuts on the upper side. The lock nuts allow you to lock it without pressing the foam too much.
I did the same as Avi... got some small bolts and locking nuts at the hardware store... nuts on top so you have a smooth bottom. (starting to sound vulgar.) Be careful to get it tight but don't compress the foam too much, as it's easy to do. I ended up putting a little glue on the nut/bolt as I couldn't get a really tight fit at first. It's been good ever since...
Progress! Here she is with the gear (and a few substitute weights) laid out. On my not-very-accurate scale I get a hair over 2lbs and balance point right on the spar at 10" back from the nose. I split the difference on the mounting plate. 4 short screws for grip, and two longer ones all the way through with locking washers. If I hit something hard enough to tear that stuff loose, I suspect I'll have bigger problems to worry about.
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Last edited by GawainReif; 20th October 2014 at 11:08 PM.
2 lbs? Sound to good to be true...