Friday, May 18, 2007

SDM Piper Cub Motor Upgrade



My buddy, Dave, wanted an inexpensive 3-channel plane so he bought the SDM Piper Cub from Harbor Freight Tools for $79. The plane did not fly stock so he decided to upgrade the motor and prop size per suggestions from "Shun Da Piper Cub" forum from rcuniverse.com. The guys on the forum are very nice and helpful -- plus they are quite innovative.

UPGRADE COSTS:
$30 -- 9.6 v 1000 mah batt (Parkzone)
$30 -- charger
$2 -- firewall for motor (from the Parkzone Piper Cub set up)
$25 -- motor/gear drive/prop (from the Parkzone Piper Cub set up)




The photo above shows the Cub assembled with the geared motor with the motor cowl off.






The angle of the prop shaft may scare you because it is so off center. Don't worry about it -- you're good.









Using a Dremel we grinded/sanded down the stock firewall until it was perfectly flat. We then used 5-minute Epoxy to glue on the Parkzone Piper Cub firewall. Then we held the gear assembly up to the firewall and marked where the four screws will enter and drilled accordingly. We also drilled a large hole to pass the wires through into the fuselage. We wired the motor to the ESC (electronic speed control) and screwed the gear box & motor to the firewall.










Here you see the angle of the prop shaft with the cowl on.












Here, again, you see the angle of the prop shaft with the cowl on.










In order to adjust the CG (center of gravity) we placed the receiver near the servos and using double stick tape we taped the back of the ESC to the back of the receiver.

I recommend buying some one or two inch shrink tubing (it's clear and shrinks by 50%) from your local rc aircraft store and remove the casing around the ESC and receiver and sealing it in shrink wrap. They will cut a lot of weight and help the plane's performance.



In order to power the geared the motor Dave bought an eight cell 9.6 volt 1000 mah nimh battery. We soldered on the correct connections so the esc and batt could talk. This battery is heavier because it has one more cell than the stock battery, which should help with windier flights. The down side is we had to carve away the batt compartment and fill the nose with foam and slide the battery inside of it. We marked the battery with a sharpie to remind us where the CG would be with the battery. We then packed foam behind the battery in the batt compartment so the battery could not move at all.

For the record, with all that Dave has spent and time we have both invested in this plane I believe spending $159 on a Hobbyzone "Super Cub" is a much better choice. The plane is complete and very well built and perfect for a beginner. Spending less than $160 on a 3-channel plane is not a good idea unless you enjoy working on your plane, which I do, but the owner Dave does not.

Sunday, May 06, 2007

Decorating your styro plane


Here's a sneak peek of my Graupner Mini Piper, that I am converting to a Piper Grasshopper.Using olive drab (color) styro safe spray paint that I got from my local hobby store (lhs) I painted my plane with the LIGHTEST coat that I could that fully covered the plane. I taped off the areas that I wanted to paint my stripes and then sprayed it. I also taped off the tires and spray painted the rims. With a brush, tape, and black and white styro safe paint I paint, I painted my army stripes. Next, I will add Army decals after I use some alcohol to clean the surface. I still need to touch it it with olive drab and a brush, especially around the nose. I made a mistake by rubber banding the nose pieces together and the glue stuck to the rubber bands. It's better to use pins only. This plane will look great when it is complete and I am so close. I bought my Graupner Mini Piper from Hobby-Lobby and it is a good first or second plane.

Flight Report: Copperhead Aviation Extra Stiffy

A great 3rd park flyer is the "Extra Stiffy" made by Copperhead Aviation. Beside my plane you will see my original radio, HiTec Flash 5 and my new lipo charger/balancer -- FMA Cellpro4. If you think that this hobby will be a long-term investment for you I recommend thinking ahead. I am very happy that I bought a radio that I could grow into, because I did not need to upgrade my radio.

This plane's performance is outstanding. It will fly vert. Imagine driving a sports car and then driving a standard car. The sports car accelerates better and corners very well, because of stiffer suspension. The same can be said about the Extra Stiffy, because the plane overflows with power and is very stiff; therefore it is very responsive in the air.

Take-off took less than 8 feet and before I knew it (in seconds) the plane was 65 feet in the air. I flew at about 1/3 throttle. The plane tracked very well. Rolls resulted in no loss of altitude. Loops and inverted loops were easy pulled off. The plane required a little speed to be landed and could be flown to the ground with throttle and no elevator.

The plane is expensive for a foamy at $89, but the reviews I have read seem to justify the costs.

www.copperheadaviation.com