Mounting Your Engine

Mounting an engine can be an exercise in futile frustration. Many of us struggle model to model with this issue. Is there a way to standardize a method and make things simpler?

The answer is yes..... If you click on the link at the title bar. you will be taken to the ZRCGF web site, in our articles section.

The article was written by Pat Roy, and it takes into account years of experience in mounting engines. The exercise in mounting an engines does not need to be difficult OR expensive.

The engine mount does need to be sturdy, well thought out, and be adaptable to whatever engine we want to mount on the airframe. This article hits all the marks.

Follow the directions and you will have a mount that will serve you and your airframe well! The big plus is that this method can be used on most any airframe and any size plane.

Ignition Systems and Interference

The biggest challenge that all of us gas guys face is ensuring that our planes fly interference free.
The First, Foremost and BIGGEST reason is Safety. The far distant second reason is the cost of replacing that beautiful bird. Oh, did I say mention SAFETY!!

RFI - Radio Frequency Interference - will be evident immediately if using a PPM receiver. Do not fly until you obtain excellent engine running range checks with a PPM receiver. Using a PCM receiver for initial range checks frequently masks some RF issues which can later push through the ability of a PCM receiver to filter them out. A crash comes almost immediately after that happens.

So the key is using a PPM receiver for those first critical system checks, not a PCM receiver. Engine off to establish a baseline, then engine running. You want no worse than a 10% difference between engine off and engine running range checks. Over 90 to 100' for a minimum distance, engine running. If you do everything right and have problems do not fly until EVERYTHING is working properly.

What about the 2.4 GHz frequencies that are quickly overtaking the 72 MHz market? You have probably heard that using the 2.4 GHz radios will eliminate you concerns. Right? In fact, it is absolutely incorrect to assume that is the case.

You keep believing that and you're sure to lose a plane. You won't be alone. Others have already gone before you with the same belief. Where the receiver is mounted is not nearly as critical as assuring that you don't have RF issues at all. I've been mounting radio components in close proximity to ignition systems for many years but what has permitted that to work every time is using good components in great condition and making all the checks to assure that any issues were eliminated prior to flight.

Using 2.4 GHz radio does not eliminate RFI, and the 2.4 GHz systems are still subject to various forms of jamming. If one has failed to achieve adequate range checks with the engine off and the engine running the loss of an aircraft is only a matter of time. Using 2.4 will not eliminate that problem, nor will PCM. Both only reduce the chance of a crash from ignition RFI, with 2.4 being better than 72 MHz PCM.

Never rule out anything when it comes to airplanes.

Click here - The ZRCGF website contains further information and checklists to use in finding these potentially unsafe RFI problems.

Best Propellers to Use for RCGF Engines

by Pat Roy

So what is the best propeller to use - wood, carbon fiber, ? This is one of the more popular questions we get!

For any given plane and engine combination, there will be a propeller that will work best for the type of flying desired. 3d, IMAC, and scale flying each require a different type of propeller response, while each airframe engine combination exert their own influences. Rarely will you find two propellers exactly the same, and blade lengths, pitches, widths, tip shapes, and flexibility vary widely between brands and composition types. "Size" covers a lot of territory with propellers.

The word "typically" will be used quite a bit here because the descriptions that follow are not hard and fast rules, but a generalization.

Wood blades typically "spool" up faster because they are generally lighter than other types. The downside is they can be more flexible and therefore less efficient. A laminated wood prop diverges from the lighter, more flexible description though. They generally are more rigid and are heavier than a comparable propeller cut from one piece of wood.

Carbon composite props are typically more rigid and have more consistent design and mold accuracy while frequently generating more rpm than a wood prop due to blade design and rigidity. Propeller weight increases when carbon composites are used.

Fiberglass composite propellers are typically very "mold accurate", but are slightly more flexible than carbon composite propellers. Propeller weight can be quite light for the size. Generally they are not as desirable for larger displacement engines. Fiberglass propellers are limited in available sizes because of safety concerns when used with large gas engines. Drilling fiberglass propeller hubs for multi bolt engine hubs can create safety issues for larger gassers.

Unfortunately there is no "best" propeller type. Nor is there a "best" propeller that someone could ask for to provide the perfect performance for "their" particular plane. There will always be some variance due to fators induced by the person that assembled the plane. Final weights, engine choice, and desired flying style can make the prop you want or need differ from what works best for a person flying the same plane right next to you.

News from the Front

Wow...
It has been a couple of weeks, and it only seems like hours!! Lots of things happening on the RCGF Engines front lines.

First off... Thanks to all the guys who are writing me about their RCGF engines, and the posititive experiences you are having. PLUS...the "things you would like to see" stuff in future engines is absolutely the best. Your ideas have all been heard - loud and clear... and the factory is examining ALL of them.

In fact let's talk about the current batch of improvements that are coming NOW.

1. Carburator orientation - When you get the engine, the carb is mounted with the low and high speed needles facing up - in the same direction as the cylinder. Many of our models require that the engines be installed inverted. Now the needles face downwards.

What modelers did not realize - and that is our fault for not promoting this - is the carby can be upbolted and a moved 180 degrees, so that it is facing up again. This is also great if you plan on using a Pitts style muffer.

Now here is the other part. The carburator can also be rotated 90 degrees in any direction. That means that now you can move the carby in 90 degree rotations to suit YOUR needs. Right now you will have drill and tap the holes if you wish to use the 90 degree rotation option. The factory will be drilling and tapping these holes now. The good thing is that the factory also makes the adapters.

2. Spark plugs - All engines can be retrofitted to use the CM-6 spark plug. These are 10mm
plugs. Our standard plugs are 14mm. Starting in December, we will be outfitting all the twins - 50cc Twin, 100cc and 150cc engines with the CM-6 plugs.

The biggest advantage is the size of the plug. It is about 1/2 the size of the standard plug. This plug provide modelers with a smaller footprint. This will allow more "in the cowl" installations for models with narrower dimensions.

Upgrade kits are available, so any RCGF engine can take advantage of the smaller footprint size. Though not confirmed yet, we may be putting the CM-6 plugs into our 20cc engine as a standard . Stay tuned for lots more information on this.

The factory has really been working with us on getting these great updates out into your hands.