I'm building my first ARF- a 4*60 and am at the point where I mount the engine. How do I determine the exact location of the engine in terms of front to back? I know the propeller and spinner have to clear the front of the fuselage, but is there a way to be more exact? Won't this location really affect the final balancing of the plane? The needle adjustment on my Thunder Tiger .61 does not come out from the carburetor at a 90 degree angle, so the precut notch in the fuselage doesn't line up. I guess I just cut a new notch or hole?

Thanks.

I used the location to achieve the proper cg. Used a magnum 80 four stroke and actually had to put a one inch block between the firewall and motor mount to get balance. This was a kit and was pretty tail heavy to start. Could have added weight instead but didn't want to make it heavier. You will enjoy the 4*60. It is a great plane.

Cap'n Bob

Thanks for the reply. So I guess it's a matter of using the adjustable engine mount and deciding on the location of the engine based on how it balances later on in the building process? Thanks

I spaced mine so the prop was about a 1/4 to a 1/2" clearance in front of the fuse. If you plan to use the engine location to balance your plane, be sure your radio is installed FIRST! It is best to mount the engine first, as close as possible to the firewall, then balance with the radio parts. You really only need a minimum (1/8") of clearance for the prop. I had both a .91FS and Saito 100 in it (at different times of course) and it flew great!

Hello,

I have a 4*60 ARF with a Saito 100. This is only my second plane, so I am not an expert, but here's what I did. I installed the adjustable engine mount that came with the ARF. I then installed a prop and spinner on the engine and test fit it on the engine mount in a location that provided both the necessary clearance and a decent CG. I also stuffed the radio gear in the fuselage in the approximate location and tested the CG right side up, instead of upside down like you will ultimately do, so that the engine could just sit on the mount and I could test it in different locations.

Travis

I too have a 4*60 that was VERY tail heavy. I placed the engine on the mounts so that I left room behind for the fuel tank lines, and in front of the fuse front for the prop to clear. I think the instructions have the distance indicated. I used and OS91 Surpass for the engine, put the battery in the nose just in front of the bulkhead behind the fuel tank, moved the radio as far forward in the servo well as possible. I still had to add 2 oz's in engine well, a 2 oz spinner weight, and a packet of large washers in between the fuel tank and the battery. Yes the plane is heavy, but it is fun to fly, and I have other aircraft that I can have just as much fun with and are more manueverable. It really boiled down to the addition of Super Mario as my pilot. That added a lot of weight since it started its life as a Bobble Head doll. You probably won't have the same problem.