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I do build rotary engine mounts as many of you already know. It started out a couple of years ago with the Motor Mount Plate concept. That was abandoned when Bill Schertz invented the beam mount which is much better in every way. Lighter, stronger, cheaper. In response to an inquiry yesterday, I sent the following info, that I would like to share with every one. The question was could I supply an engine mount for the RV6 tri gear.
The short answer is Yes. The engine mount I build is called an S-beam (Schertz Beam) mount. The concept was first developed by Bill Schertz and was modified by Paul Lamar and others until it evolved into the present configuration. The S-beam mount only supports the front of the engine. The rear engine support is provided by a adjustable strut that runs from "someplace" on the back of the engine to "someplace" on the firewall. The "someplace" varies from plane to plane. For some aircraft, such as the Kiss Cruiser that have a plywood firewall, it is no problem at all. For others such as the RV, the sheet metal firewall may have to be reinforced where the strut attaches. I say "may" because it might be possible, in your case, to tie into the nose gear assembly instead of the fire wall. I do not provide the rear strut as part of the engine mount package. It is easy to build.
Another complication is that the starter has to be relocated from 6 o'clock (on Tracy's drive adaptor plate) to some other position such as 3 o'clock. The reason for this is that the S beam blocks the 6 o'clock position. If you are planning to put the radiator underneath, then you probably would want to relocate the starter anyway. If you are thinking of using cheek radiators, then moving the starter to either side may not be a good idea. Each Installation has to be evaluated individually.
A third issue is that the S Beam replaces the lower spacers that Tracy supplies with the drive. I have not asked for nor received permission to do this from Tracy and he may well void the warranty on the drive. If our positions were reversed that is what I would do. The steel spacers I use with s-beam are precision ground to .5 thousands of an inch tolerance. Relocating the starter requires welding an extension on the drive adaptor plate which I can also do. Once again this has not been authorized by Tracy.
If you decide to have me build the engine mount, I will need a physical template of the engine mount attach points on firewall and I will need to know the distance from the firewall to the face of the prop flange on Tracy's drive.
The S-beam engine mount was developed to make it easier to put the radiator under the engine and to fit the exhaust system including turbos.
The cost, including starter relocation, is $850.00. A fifty per cent deposit is required. The balance can be sent when the engine mount is ready to ship.
Normally it takes about one month to build an engine mount. Jerry
P.S. I do not build engine mounts Jan and Feb as the shop is too cold.
S-beam with engine.jpg
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