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Old 08-04-2011 | 11:21 AM
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Swift427
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From: Minneapolis, MN
Default SuperCup B/less Conversion ... WHY ?

With respect to another members previous SC b/less conversion and any discussion about any significant change in thrust angle relative to CW vs CCW motor rotation relative to using a left-handed vs right-handed prop ... it probably isn’t all that big of a deal … EVEN if the stock 480 brushed motor (w/gear driven prop) on the DSM & LP is wired for CCW rotation so the prop spins CW. Being it’s a brushed motor we’d assume it’s wired for CW rotation in which case the gear driven prop is spinning CCW and the stock prop is actually a left-handed prop or pusher prop that’s been adapted for tractor/puller application. However, the motor torque to the airframe is still CW being that the brushed motor is rotating CW.

IF the gear driven prop is spinning CW it means the motor/torque is rotating CCW. If this were indeed the case then there might be some justification for using a left-hand pusher prop (converted for tractor/puller application) on his direct drive b/less outrunner wired for CCW rotation. However, the SuperCub is considered an inexpensive 3-channel beginner plane not a pylon racer or aerobatic plane that requires precision handling by the pilot … in which case(assuming the SC were a precision aircraft) when changing the motor's torque/thrust angle from CCW to CW rotation, then it may make some sense to use a CCW rotating 480 inrunner with pinion and gear drive setup … ASSUMING THE STOCK 480 BRUSHED SC IS ACTUALLY WIRED FOR CCW ROTATION..

The REAL bottomline question here is: Is the difference in flying enjoyment (3-channel) worth the extra time and expense to convert/modify to b/less even if you can buy most of the items via HK and rob some of the parts from another crashed plane.


E-flite EFLM1505 Park 480 Outrunner 1020Kv $49.99
http://secure.hobbyzone.com/EFLM1505.html

Custom RC Parts CRCA1021 (A100021) Motor Mount $15.99
http://secure.hobbyzone.com/CRCA1021.html

E-flite EFLA1030 30-Amp Pro Switch-Mode ESC $44.99
http://secure.hobbyzone.com/EFLA1030.html

ParkZone PKZ1090 Servo $13.29
http://secure.hobbyzone.com/PKZ1090.html

Lipo manufacturers have up to three different ways of referencing the three dimensions. ParkZone references the 15C 1300mAh according to its position in the SuperCub LP with relation to the plane’s dimensions of length, width and height as the lipo is positioned in the battery compartment. However, we sometimes think of the width of a lipo as being its narrowest dimension as apparently does E-flite; whereas many lipos are positioned in a plane laying down so the lesser dimension is sometimes referred to as its height as does Thunder Power’s method of referencing the lipo's dimensions. Other pilots/planes position the lipo on its side when the battery compartment is in a narrower cockpit location as apparently does E-flite’s method of referencing their lipos width & height dimension.

In order to get at least as much flying time with a b/less mod as with the stock setup a 2100mAh lipo is suggested. However, as you can see below the SC LP battery compartment will not accept a 4 inch lipo laying down. A modification opening has to be cut out of the battery compartment to allow it to extend upward into the plane. So, when referencing the relative dimensions of the Thunder Power 25C 2100mAh lipo shown below as positioned in a modified SuperCub LP b/less outrunner could be …

Height:4.06 in (103 mm)
Width:0.83 in (21.1 mm)
Length:1.38 in (35.1 mm)


ParkZone PKZ1033 15C 1300mAh LiPo $23.99
http://secure.hobbyzone.com/search/PKZ1033.html

Length:2.76 in (70.1 mm) (length of battery compartment to length SuperCub)
Width:1.46 in (37.1 mm) (width of battery compartment to wingspan width of SuperCub)
Height:0.83 in (21.1 mm) (height/depth of battery compartment to SuperCub height orientation)
Weight: 4 oz (113 g)


E-flite EFLB21003S 20C 2100mAh LiPo $ 34.99
http://secure.hobbyzone.com/eflite/e...FLB21003S.html

Length: 4.05 in (103 mm) (height/depth of modified battery compartment to SuperCub height orientation)
Width: 1.05 in (26.7 mm) (width of battery compartment to SuperCub wingspan orientation)
Height: 1.35 in (34.3 mm) (length of battery compartment to SuperCub length orientation)
Weight: 6.6 oz (187 g)

Thunder Power Pro-Lite THP21003SPL25 25C 2100mAh LiPo $39.99
http://secure.hobbyzone.com/THP21003SPL25.html

Length: 4.06 in (103 mm) (height/depth of modified battery compartment to SuperCub height orientation)
Width: 1.38 in (35.1 mm) (length of battery compartment to SuperCub length orientation)
Height: 0.83 in (21.1 mm) (width of battery compartment to SuperCub wingspan orientation)
Weight: 5.19 oz (147 g)