ESTES Model #9710
The Pro Series II line just got a new member! Meet the Super Big Bertha, featuring a BT80 (2.6 in/66 mm) diameter body tube for your building enjoyment. Standing over 36 inches tall, the Super Big Bertha comes with the quick release motor retention system just as the other Pro Series kits do. (9750 Pro Series II 29MM Retainer Set – is also sold separately). Construction of this kit is not difficult and the altitudes you will reach are very impressive! Building and finish work can easily be accomplished over a few days. AND did we mention its a bring back from around 1990?
- Length: 36.8″
- Diameter: 2.6″
- Weight: 8.9 oz.
- Fins: Laser Cut Wood
- Decals: Waterslide
- Altitude: 1200′
- Recovery: 24″ Parachute
- Recommended Motors:
- E16-6, F15-8
- 08/22/2018 – Purchased Estes Big Bertha Pro Series II from Estes for $39.99 (Retail $39.99).
- 11/16/2019 – Took pictures of package and components. Scanned decal, fin sheets, centering rings, shock cord mount, and plans.Measurements on page 44 Book #4.
- 12/11/2018 – Cut out centering rings, fin sheet pieces and made copy of fin slot guide. Cut fin slots from guide sheet.
- 12/15/2018 – Glued fin skins to center support structures.
- 12/16/2018 – Sanded fin edges smooth. Cut fin slots into lower body tube. Filleted centering ring joints. Drew launch lug line half way between fin slots and marked the bottom of the aft launch lug line at 12″
- Glued tube coupler into upper end of lower body tube halfway. Glued motor mount assembly inside of lower slotted body tube.
- 12/17/2018 – Glued fins into lower body tube slots.
- 12/18/2018 – Filleted fin joints. Applied Harbor Freight weld to tube coupler and joined body tubes together. Glued launch lug at 1/2″ and 12″ marks. Glued shock cord to mount and then inside body tube.