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New US 40 pre-assembly advice?

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Old 10-29-2002 | 03:06 PM
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Default New US 40 pre-assembly advice?

I have a brand new Ultra Stick 40 and Saito 72 combo. I am wanting to know what are some of the preassembly things to do. I have heard that the gear is a week spot. Mine has some tri stock there. Is more needed and how. Also I have heard that the motor mount is weak...
Old 10-29-2002 | 06:48 PM
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Default New US 40 pre-assembly advice?

It won't hurt to reinforce the firewall - put some triangle stock on the back side and epoxy it in.

Also make sure your on/off switch is opposite the breather nipple (on the engine). I mounted mine engine 90 degrees from upright and the left side of the fuse had more fuel residue than the right side! And guess where the switch was

Also, test the tank for splitting - I didn't and should of!

Jerry
Old 10-29-2002 | 08:03 PM
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Default tips

I would replace the tank. I had many tank problems (thought it was engine problems) including a split tank. It dumped fuel in the wing saddle area. I picked the plane up by the gear one day and it pulled loose. I don't know if it was the fuel (probably) so I would reinforce that area with a little glass cloth. The decals will delaminate after a few flights and start to peel, so I would leave them off. Go over all the Ultrcoat seams with a hot iron. I've had some come loose and allow exhaust gunk to get underneath. These are great flying fun aircraft. I know you will enjoy it with the Saito 72.
jpflyer
Old 10-29-2002 | 08:03 PM
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Default New US 40 pre-assembly advice?

Let me think.
  • Pin your firewall with dowels (toothpicks) and epoxy.
  • Reinforce the landing gear plate using tri-stock and epoxy. You want to tie the plate to the sides of the fuselage.
  • Use 8-32 nylon bolts and matching blind nuts to hold the gear on instead of the supplied metal bolts. Its much easier to replace broken plastic bolts than to repair the fuse/gear mount plate.
  • Use 3"-3.5" Sullivan skylite wheels instead of the supplied 2.5" rubber ones. Extra ground clearance for the 13" prop you'll be swinging.
  • Use a 13x6 APC prop. With that motor you should get into the mid-9000 RPM range - plenty fast and lotsa thrust.
  • Check the supplied motor mount carefully. Many have had problems with their mounts cracking. Better yet, replace the metal H9 mount with a GP adjustable one - less weight in the nose.
  • Tailwheel - on my first one I used a Dubro tailwheel mount. On Sticks #2 and #3 I used the supplied one. Both worked. as there isn't a lot of stress on the tailwheel of this bird.
  • Run a bit of tubing to redirect the oil from the crankcase vent. My .72 slobbered quite a bit, and doing this made cleanup a little less time-consuming.
  • If you're using the quad-flap option use servos that center properly! Having 4 wing surfaces that don't line up consistently is a PITA.
  • You'll need weight in the tail for balancing - put your battery back there. Cut a hatch in the top-rear fuse and velcro the battery in place. Cover the hole with tape. Fly the plane and shift the battery as needed to achieve your preferred balance point. Once you get the CG where you want it CA in a couple of balsa sticks to keep the battery from shifting fore and aft, then cover the hole with Ultracote.
That's everything I can remember.
Old 10-29-2002 | 08:15 PM
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Default New US 40 pre-assembly advice?

Another thing. Flap and Crow settings both need to have a little down elevator mixed in. Use the supplied guide in the manual as a baseline and adjust to suit.

With an aft CG the plane will perform as described in the ads... you can shoot landing approaches from 75-100 feet up... crow ON, dive for the runway threshold with throttle at idle, pull level and she slows to a crawl, touchdown at well below walking speed. Such a fun plane.

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