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I've been flying my H Model 40% ASH-31 for about 4 years now. At close to 50 lbs the retract takes a lot of force on take-offs and particularly on the landings.
The airframe has a very robust retract unit with a friction brake as well. 2 servos are used for this, one for the retract mechanism and the other for the brake. These are mounted onto the sides of the retract plates using carbon fiber/fiberglass/resin servo mounts. The one for the brake is not put under a great amount of stress, but the retract servo and its mount do take quite a bit of force.
The resin mount for the retract servo gave way while I was in Cumberland, giving me a great opportunity to make a new one. The forward arm of the mount failed where the screws that hold the servo go through. Please note this is not due to any issue with the workmanship of the airframe or the servo frame, but rather my use and wear due to 4 years of take-offs and landings.
Here are a couple pictures of the resin mount (you can see the cracks on the second picture on the arm on the left):
I picked up some right angle aluminum stock from Online Metals:
They sell stock in small to large sizes, making it easy to get pieces that are only 12" in length. The angle stock I purchased is 2" x 2" x 0.1875" thickness:
I was very fortunate a year or so ago to have a friend offer me a Sherline metal lathe and metal mill. This was a perfect time to get them out to create a new mount for the retract servo:
I used an end mill to create the open space for the servo in the frame. I did take out excess aluminum with a bandsaw prior to milling the final frame, making completion take less time. In addition to milling the width and depth of the servo space I also milled the width of each long edge/side. It is amazing how precise the mill is, allowing the creation of parts that have very close tolerances and fit.
After the correct milling for the width and depth of the servo was completed I then used the servo to mark the correct placement of the servo mounting screws. I changed the end mill cutter over to a chuck and drill bit and was able to drill out the initial holes very precisely. These were then tapped for cap head bolts for the servo to be held in by.
Two holes were also drilled into the side plate where it is attached to the retract frame. These are the countersunk for the mounting screws to be flush with the servo frame and not interfere with the servo.
The servo was then mounted and I put it in place with 4 cap head bolts, using nylon insert lock nuts underneath to make sure it won't come loose:
After this was completed I then bolted it to the side frame of the retract and then re-attached the servo arm and link for the retract. A few minor adjustments to the servo throws and it works perfectly:
Tomorrow I'll reinstall the retract unit back into the fuselage and complete the work on putting the gear doors back in place. Waiting on a couple springs that should be here tomorrow or Wednesday and then it will be ready to fly again.
The airframe has a very robust retract unit with a friction brake as well. 2 servos are used for this, one for the retract mechanism and the other for the brake. These are mounted onto the sides of the retract plates using carbon fiber/fiberglass/resin servo mounts. The one for the brake is not put under a great amount of stress, but the retract servo and its mount do take quite a bit of force.
The resin mount for the retract servo gave way while I was in Cumberland, giving me a great opportunity to make a new one. The forward arm of the mount failed where the screws that hold the servo go through. Please note this is not due to any issue with the workmanship of the airframe or the servo frame, but rather my use and wear due to 4 years of take-offs and landings.
Here are a couple pictures of the resin mount (you can see the cracks on the second picture on the arm on the left):
I picked up some right angle aluminum stock from Online Metals:
They sell stock in small to large sizes, making it easy to get pieces that are only 12" in length. The angle stock I purchased is 2" x 2" x 0.1875" thickness:
I was very fortunate a year or so ago to have a friend offer me a Sherline metal lathe and metal mill. This was a perfect time to get them out to create a new mount for the retract servo:
I used an end mill to create the open space for the servo in the frame. I did take out excess aluminum with a bandsaw prior to milling the final frame, making completion take less time. In addition to milling the width and depth of the servo space I also milled the width of each long edge/side. It is amazing how precise the mill is, allowing the creation of parts that have very close tolerances and fit.
After the correct milling for the width and depth of the servo was completed I then used the servo to mark the correct placement of the servo mounting screws. I changed the end mill cutter over to a chuck and drill bit and was able to drill out the initial holes very precisely. These were then tapped for cap head bolts for the servo to be held in by.
Two holes were also drilled into the side plate where it is attached to the retract frame. These are the countersunk for the mounting screws to be flush with the servo frame and not interfere with the servo.
The servo was then mounted and I put it in place with 4 cap head bolts, using nylon insert lock nuts underneath to make sure it won't come loose:
After this was completed I then bolted it to the side frame of the retract and then re-attached the servo arm and link for the retract. A few minor adjustments to the servo throws and it works perfectly:
Tomorrow I'll reinstall the retract unit back into the fuselage and complete the work on putting the gear doors back in place. Waiting on a couple springs that should be here tomorrow or Wednesday and then it will be ready to fly again.
That's funny! Anyway... glad it's fixed. I love watching those big glass slippers fly. Can't wait until my skill set is up to flying one!
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