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Jul 15, 2016, 03:16 AM
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Build Log

Horizontal Tail, clevis, and control surface centering. Wing Folding


Page 6 shows B screws being inserted from the top down. Don't insert them from bottom up!
This clevis installation is not what came with the Timber. Remove the rudder and elevator servo arms and check for binding of the pushrod wire and plastic tube. RCGroups has reported problems with binding that required sanding/cleaning of the pushrod. The bolt that secures the pushrod at the elevator servo arm is a critical part. If the bolt stops pinching the rod then the elevator is compromised and pitch control will be erratic or lost resulting in a crash. I do not recommend thread locking as this strips the screw when adjustments are needed or when pushrod needs to be pulled out or in. A better solution is to use a 1/16" wheel collar in front and aft of the metal barrel. This will prevent slippage when it occurs.

Control Surface Centering is critical for both SAFE Self Level On or Off. Mechanically center all surfaces after TX has been bound and double check by using a straight edge. On first flight takeoff with SAFE switched off. I recommend takeoff flaps with or without slats installed. Use about half throttle and what ever elevator trim needed to fly level hands off. You can trim ailerons for wings level flight. You can verify SAFE self levels at altitude by moving your selected switch but it's better for the gyros to have zero trim at the TX. So land and measure or mark what your elevator setting is. Zero out your TX trims and mechanically adjust your elevator to what you marked or measured previously.

Some have reported that the gyros have not been programmed properly and that the gyros want to produce a nose down attitude. Matt Andren the designer posted nose down to be true so as to prevent a nose up stall on approach to landing. With takeoff or landing flaps selected I have had to use slight up elevator for approach, flare, and touchdown. I don't mind this and although I could put in a Flight Mode Trim I'm going to keep TX programming simple. Others have experimented with tilting the RX up or down to achieve level flight. I have not had to do this with the 3 Timbers that I've assembled and maidened at our club field. Unlike the Apprentice where power pitches he model up or down the Timber is neutral and elevator is primarily use for pitch changes. This is the same on many full size aircraft designs. It's not wrong but something that you have to learn and remember.

I did completely pull out the RX from the fuse glue joints when disconnecting the stock Y cables from the wing plugs. Of course the RX was not secure and this would have caused problems in flight. So it's a good idea to replace the short/tight Y cables with longer ones that are easier to insert and disconnect. While you are inserting new aileron and flap Y cables using a Harbor Freight Hemostat go ahead and insert a 4-6" aileron extension into the bind slot of the RX. This will make binding and re binding easier.

So there are 6 connections to make from the fuse to wing. I recommend using painters masking tape to label and Mark each of the 12 connections. This will make it easier to check later. The two cables coming out of the front wing hell are the ailerons and lights. The light plugs have the metal pins. The cables coming out of the aft wing holes are the flaps. It makes no difference hooking up the left or right ailerons or flaps. The right aileron can be plugged into the left Y connector.

Now there is a mess of wires floating around inside the fuselage and there is a good chance that you will have wires sticking out at the saddle. This is one reason why I made a harness with shorter wires and only 2 connectors. However If you want to remove the wings but keep the wires connected here is an RC post with the wings folded back and secured with the wing nylon bolts. I tried it and it works but the trailing edges of the flaps get dented when they hit the top fuselage light. A guard could be usedto prevent this as well as a pin or device to keep the wings from unfolding.
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