How to build light engine mount ?
 

Hi All,

I am flying 3D planes in the .40 - .50 range. The new ARF's are built lite, and the accessories weight becomes an issue. I am most concerned about the engine mounts that are usually supplied with the model. It is often made of heavy metal. The mount may weight as the whole fuselage airframe !! I also found out that most of the nylon mounts int the market are pretty heavy (Great Planes mount for instance). I found Dave Brown's mounts to be relatively lite, but fragile.

I want to design and build my own engine mount, that will be very light, and cheap (no carbon here...). It has to be easy to mount, and replaceable. Do you guys have any ideas ?

Yaniv.

RE: How to build light engine mount ?
 

By the time you're finished it will weigh as much as a commercial mount. You can make it out of wood, cut your own metal, use beams or whatever. The system has been developed over a long period and already has a good strength to weight ratio. If you aren't willing to shell out for carbon fiber or titanium, you may as well buy a glass/nylon mount.

RE: How to build light engine mount ?
 

I have made many engine mounts in the past - not specifically to save weight - just to mount an engine when a commercial item wasn`t available.

A design that worked well for me was to cut two pieces from a piece of scrap ali angle extrusion and put them bac-to-back to form a 'tee' configuration. One piece had the engine mount holes drilled oversize, and the other was tapped for engine mount screws which held the assembly together. You could go mad and drill lightening holes all over it if you wanted to, but the regular finished article was pretty light in itself.

1/8" thickness would be fine for your engine size.

Alan W
Alan W

RE: How to build light engine mount ?
 

Hi Alan,

I was also thinking about ali angle. I like the idea of putting one on top of the other. If I understand your description correctly, then you are buildeing a 'T' for each side of the engine. What I did not figure out is how to attach the two 'T's to the firewall.

Yaniv.