Aeromarine Scorpian for
Q & S Offshore
By Ken Joye
FE racing has seen a growing interest in the
larger boats and Q & S Offshore is no exception. The following article is
on how I set-up my boat for the upcoming season.
One of the
boats in my arsenal that surely gets my heart thumping is my Aeromarine
Scorpian. I’ve been testing a motor in with the support of Andrew
Gilchrist of fastelectrics.com and think I have a competitive set-up for
the upcoming season.
Recipe for Excitement!
32”Aeromarine Scorpian low profile f/g mono
Neo 12v from FASTELECTRICS.com
Airtronics 2ch pistol grip and std. servo
x442 Offshore (enduro), x645 Mono (sprint)
.130 flex cable to 3/16-stub shaft
Octura .130 flex hex modified for 6mm shaft
3/16 (fin removed)
5 Racing w/FULLERS wedge rudder
The 32”Aeromarine Scorpian is a first class,
high quality fiberglass nitro hull that is light enough for FE use. (
approx. 2lbs w/o hatch) Its streamlined low profile and ability to handle
rough water are just some of the reasons for purchasing the hull.
I choose not to use the fiberglass cowl in
favor of saving a little weight. Instead, I constructed a lid made from
sheet styrene with a couple of model airplane WWII fuel tank ˝ sections
and made a nice twin canopy cover. The hull also came with nitro engine
stringers that were removed with a dremel in areas not needed, to save
weight. After being primed and sanded for proper preparation the hull was
painted with hardware store spray enamel. Gunmetal gray was chosen to
follow along with the ‘Thunder’ theme of my offshore boats.
The motor used is the powerful LM800BBX Neo
This motor, another exclusive to Andrew
Gilchrist's arsenal of Lightning Man Neo powerplants is rated at 12v.
Andrew claims with proper cooling and prop set-up it can handle 18 cells
and I’m a believer. The motor has replaceable brushes with unique brush
retainer caps that make it easy to inspect or change brushes. The motor
came with brass cooling tubes soldered to the motor contacts for brush
cooling and Deans wire for power. A spare set of brushes is supplied with
each motor. I fabricated a cooling coil made from 3/16-dia. aluminum
tubing to handle unwanted heat.
A mount was cut from 1/16 aluminum plate.
(Acts as a heat sink) The LM800BBX has (3) mounting holes for positive
location with 4mm self tapping sheet metal screws. An Octura 5mm hex flex
was machined to 6mm to fit the motor shaft and handle the power transfer.
I like to position my mono motors as far aft as possible. This allows the
direct drive flex cable to be shortest length possible for less
resistance. The C/G can be adjusted by moving the nicads fore and aft to
balance the boat.
The Out-drive assembly is made from aluminum
Beam Compass stock. It was notched out and drilled to accept an Octura
3/16-strut assembly (minus the fin) and a FULLERS wet wedge rudder. The
aluminum channel is fastened to a piece of hardwood, epoxied vertical to
the transom from inside the boat to give the transom a clean look. (This
method also eliminates the need for heavy transom doublers)
Cooling lines scavenging from prop-wash are
plumbed to the motor while the rudder pick-up handles the ESC cooling
needs. I prefer to mount my rudders on center for Offshore enduro because
the boat must turn right and left. The .130 flex cable spins through a
Teflon tube shielded in brass tubing that exits at the very bottom of the
transom. The prop shaft is set parallel or neutral for maximum efficiency.
Dual turn fins and trim tabs were added to
generate more stability in the corners. The tabs were fabricated from 1/16
gage aluminum sheet stock and have a ride pad area of 2”wide by 1”deep.
The fins are leftovers from a Graupner hardware kit.
I found the x442 prop gives maximum run time
at competitive speed for offshore competition while the x645 prop can be
used for impressive speeds in mono sprint classes.
The electronics were the last thing to be
added. A standard servo for rudder control was mounted on the right side
hardwood stringer just aft of the motor. The Tekin 432m ESC and
Airtronics receiver were mounted on the left side floor rear using Velcro
tape. The (18) 2400 nicads as were positioned on center about 3” in front
of the motor and secured with Velcro tape. The antenna tube exits out the
right rear corner of the deck. Deans 12 ga. wire was used with Sermos
Performance and Enhancements
The Scorpian is a constant head turner at the
pond. Combined with the LM800BBX Neo, the Scorpian can be setup for fun or
competitive racing. The motor has an excellent power band and really makes
the Scorpian fly.
Because the hull was designed for nitro
applications it has only one set of lifting strakes. In calm water
conditions it has a tendency to run slightly wet. I recently added an
additional set of strakes. They are centered between the existing ones and
the keel; in hope the boat will air out and increase overall performance.
I’m convinced more test time with these changes should yield positive
In closing I’d like to thank Andrew
Gilchrist from fastelectrics.com for all his advice. Fastelectrics.com
carries high quality LM Neo motors, hulls and FE racing supplies. Also
Aeromarine, for creating a great quality contender for fast electric
applications. Aeromarine hulls are available from www.finedesignrc.com.
Fine Design has a wide selection of hulls, Cordite motors and FE racing
supplies. Also my wife Nancy for letting me have the ‘shop time’ to do FE