Brief Description: Setting Main Gear Alignment (Part 1)
The instructions were ambiguous and unclear at this point; plus you can’t snap the centerline chalkline as the instructions dictate as the nose wheel is in the way.
First, do not hang the plumb bob off of the prop hub! The engine mount has a slight right offset built into it to compensate for the left turning tendency of the aircraft. If you centerline off of this, you will be at least 2” off!
Here are the steps that I followed:
1. Get the nose wheel at straight as you can and then somehow lock it in place so the aircraft will not move up front. Adjust the main wheels facing straight to start with. They don’t have to be exact, just really close.
2. Hang the plumb bob on the rear lower rudder bracket and find the center line at this location. Mark it with something on the floor. We’ll call this Point A.
3. Hang the plumb bob from the engine mount where the nose gear leg slides into the mount. This is the true center of the front of the aircraft. We’ll call this Point B.
4. Snap a chalk line between Point A & B.
Find the center of each gear leg at the axle by placing a square on the floor, touching each side and transferring a mark on the floor. You will have two marks on the floor that represent the width of the gear leg, (at the axle). This should be about 1 inch. Dimension the center and repeat the procedure for the other side.
5. Snap a chalk line between the two gear leg centerline marks. This line will cross the fuselage centerline, and you should have a cross on the floor. Measure the distance of each mark from the fuselage centerline. Write them down.
6. Measure forward on the fuselage centerline 57.5” from the point where the gear centerline intersects the fuselage centerline. Mark this point on the floor.
7. Measure forward from the main gear centerline 57.5” and mark a point for each side. Use the fuselage centerline and the dimensions found in step 5 to keep everything perfectly square.
