You might look at the Dave Brown Vibradamp sport rail mount system. http://www.dbproducts.com/
It looks like it would help when mounting the big 4-strokes on profile planes.

That might be the ultimate way of a home-made soft mount, certainly easier to install the engine. I've seen engines held down by just metal strips on top of the flanges, the bolt holes are in front and back of the flanges. Just lay a silicon strip under the metal strip & under the flange, the guide pins might be needed to be sure the engine wont move. I like it, thats what so good about this forum, take an OK idea & make it better!

That DuBro system looks interesting too, but looks like it might put the engine way above the rails. If the soft mount is too soft, specially with the 4-strokers, the engine travel will make things worse. I know from experience,made one for my .46 UCD & Saito 100, I had to go back to an aluminum mount, even the FG filled nylon mounts allowed too much engine motion,the plane literally moved around on the ground!!! Really!!! Of course the 100 was way too much engine, but I liked it!!!

I have a virgin FusionX3D ARF with a YS-63 already mounted. As soon as I get the fuselage of the 10-300 off of my desk, I'm going to bring the FusionX3D in from the garage and change its mount as we have discussed here. It's good to have a test bed! I'll build a mount as described by MixMaster, etc., and I'll also get the LHS to order in a DaveBrown VibraDamp Sport Rail to try.

Fly safe, Glover

Why not just sandwitch the front of the fuse with 1/2" plywood?

I guess 200 flights might not be all that much, but 200 consecutive perfect flights? 200 consecutive perfect landings?

I am proud that I only smack the ground 2 or 3 times per flight!

Its a little bit a a job mounting the engine the way I make the soft mount, the bolts tend to thread into the fuel tubing, making it easy to pull out of the bolt hole, but it will go together & mine lasted for years/hundreds of flights, just had to tighten a turn or so every now & then, there is some wear & compression after a while. Good luck!!

That's a very interesting suggestion. Maybe I'll try that if MixMaster's soft mount technique results in a need for fuselage repair.

Fly safe, Glover


PS While waiting for the glue to dry on the last part of the fuselage cap striping, I was cruising around and "stumbled upon" a comparison of a YS-110 and an OS 120AX over on the QQ Support Forum. The YS's mid-range power was better, but the OS's vibration was much less. So the odds are that I'll have ordered an OS 120AX and an escomposites pipe before the weekend. I get lots of help from these forums.

Absolutely, 4 strokes vibrate more than 2, at least thats been my experience. I have 2 1.20AX, one in a Velox and one NIB for the Fusion. The engine in the Velox was in X100 for a while, great combo there, at 8.25 lbs, the 1.20 could hover all day. In the 9 lb. Velox, it still hovers & enough pull out to get out of trouble, not rocket thrust, but just enough. If the Fusion comes out @ 7.anything, it will be just awesome!