Q-talk 134 - Repairs to N131PS
- Category: Q-Talk Articles
- Published: Wednesday, 23 December 2009 16:24
- Written by Paul Spackman
- Hits: 2940
The repairs to my Q are well underway after the Flat Tire Incidence, resulting in a prop strike, and broken tail spring. I decided to cut the tail cone off to transport the plane home. It took about five minutes with a saber saw cut it off (that was the sawdust that caused the eye irritation) and the repair of making it removable is looking like it will be in the forty hour range with the flox to fit and final touch-up of the paint. There will be a little fairing to do on the outside when I do a new paint job.
I decided to replace the tail wheel with the Aviation Products unit suggested by Bob Farnam and others, at this time. I was surprised to find that the new tail wheel weighed about the same as the original. To get the whole effect I am installing the bell crank at the same time. I will be able to give an objective report about the handling changes having flown 615 hours with the old setup.
The tail spring has caused the most head scratching. I have considered solid steel rod, .063 wall 4130 tubing with internal support ( foam, dowel, nylon rod or nothing), heavy wall 4130 tube and replacing it with a new fiberglass or carbon fiber rod. At this point I am planning on using the fiberglass rod that is being supplied by Dave Dugas. This is a strong rod with the fibers aligned lengthwise used for guys on power lines as reported by Dave in the past. Thanks Dave. Dave has used this for several hundred hours after breaking two of the original springs.
Update?The FG rod that Dave supplied turn out to be too short for my application, so I went with .058 wall 4130 tubing with a M-" nylon rod epoxied inside. This was very springy, so I added a layer of carbon fiber uni and two layers of bid and will now fair the spring in with foam and cover all of that with another layer or two of bid.
Drilling out the old tail spring was an easy process, starting with a long 3/8" bit working my way up to %" wood auger (just what I had in the drawer and the long %" bits a little pricy). The new spring will be installed with flox as per the plans.
The new prop is due from Sensenich 2/27/09. I am sticking with the same prop 54 X 72 as this was a good match for the Jabiru.
The crank dialed in right on the money so I will watch the filter the next 20 hours with a change every 5 hours. The crank in the Jabiru is machined from a billet of 4130 and is reported to be very tough.
Paul Spackman Casper, WY
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