My original Graupner Terry from Hobby Lobby had served me well for several years but it had indeed seen better days. I had sprayed clear enamel paint on the wing which melted the foam, broken the wing after several high speed dives, and literally lost it in a pond for several hours before pulling it out all covered with black muck. After several years of abuse, it still was a great flyer but it was time to build another one.
Although my 2 year old Terry was abused and ugly, it still flew great!
I decided to cover my new Terry wing with orange Oracover. It surprised me just how much harder the covered wing became! It was rock hard and looked fantastic! Oracover is great for covering curves because it shrinks very well with reduced heat settings.
The new wing is strengthened with Oracover and the power system upgraded to a long can motor
Initially, I was going to use a Mega 16/15/x series brushless motor in my new Terry but I decided to save some money (for once) and use an existing power system from my ProJeti racing wing. Since my ProJeti had been upgraded to a Mega 16/15/3 brushless motor, my black long can Speed 400 motor and ESC were available to use. The (FK5202) Long Can 400 Motor is more powerful than a stock Speed 400 motor yet is the same 27.5mm diameter. The shaft size of 2.3mm is the same as a Speed 400 motor but the length is a longer 50mm. The motor weighs 3.6 oz. compared to the stock 2.6oz Speed 400 motor. but it can be run direct drive on 10 cells with a 5.5x4.5 Cam prop or similar. This was very close to my stock Terry prop; a Graupner 6.3x3 CAM folding propeller.
A Lithium Polymer pack keeps things light and the fuselage is strengthened with additional foam
The stock Terry pushrods are a bit thin for my taste so I replaced them with a set of Kavan HLFK0623 Electric Flight Complete Pushrods. Although the pushrods are nicely held by the Terry fuselage design, the wires extending to the servo arms and control horns would sometimes warp under high speed flight.
I eliminated the antenna wire by soldering a short lead from my receiver to one of the control rods. This technique has worked great for me in the past.
I also reinforced the fuselage bay under the wing with some foam from a GWS R4-P receiver. This foam is a tough, high impact density that adds almost no weight. The wing trailing edge has a reinforced cutout that is held by a balsa post sticking up from the aft end of the servo bay area. This locks the wing securely in place and eliminates any side-to-side movement.
The finished "Super" Terry weighs 15oz without battery
The tail was glued into place with epoxy since I had no plans to ever remove it.
My new Terry weighed less than my old one and had much more power!
To properly power my black long can motor, I needed a peak 15amp delivery at 10-12 volts. My high powered 3s6p Lithium Polymer pack could provide the current needed and only weighed 2.8oz. This would help offset the heavier motor weight.
Component Weight Comparison:
The ThunderPower 3-cell, 2100mAh pack provides a perfect fit in my Super Terry
The TP21003 ThunderPower 3-cell, 2100mAh pack is a perfect fit for my Super Terry in form and function. The 15amp delivery mates very well with the black long-can Speed 400 motor. The 3-cell Lithium voltage is equal to a 10-cell NiCd pack but the TP 2100 pack weighs only 4.6oz.