Radian Pro Wing Modification

This is by far the best modification I've done to my Radian Pro. The idea came about after suffering the frustrations encountered while assembling the wings of the Pro. You have to fish servo wires through the wing openings, then take a pair of pliers and grab the wire ends and pull them up into the radio compartment. You have to do this for both the flap wires and aileron wires. Anyone who has ever done this knows how much a pain in the ass this task is.

After doing this chore a few times, I vowed to find an easier way. First I tried making a a wire lasso that I could put down through the radio compartment and out through the wing slot. I then could lasso the aileron and flap wires and pull them up for attachment to the receiver. This works better, but still not a perfect solution and had me worried I would wear out the pins on my receiver as they are not designed for this kind of abuse.

After questioning others on how they dealt with this issue, I decided the best solution would be to take two servo extensions, Plug one into the receiver for the left aileron, the other to the left flap and then remove the connectors on the other end of the extensions and incorporate both wires into one plug, a deans four pin connector.

I would also have to remove the connectors from the wing servos and shorten those wires, adding a matching four pin connector to those wires as well. Once done, I was able to slide the wings on the spar up to the point they enter the fuselage, plug in only one connector, finish sliding the wing and bolt it up. Do this for both sides and I'm done.


 Here is a photo taken during the process of soldering both servo extensions to the four pin deans. I purchased the connectors from Horizon Hobby and they come with the shrink tubing shown.

Notice how both red(positive) wires are added to one pin of the connector and both black wires are soldered together and ready to be attached to a single pin of the connector. The other two pins will have a signal(yellow or white) wire attached to them, one from the flap channel and one from the aileron channel. In order to strip the wires back for soldering I take a #11 exacto blade and just lightly nick the wire insulation about 3/16" back from the end and then take my finger nails and pull the rest of the insulation off. If you plan on doing a lot of servo work you could invest in a set of wire strippers that will do 22-30 gage wire. I believe the wires on the Radian Pro are 22 gage. For the soldering I used this 30 watt iron from from Radio Shack. I would have liked to have something with a smaller tip and a little less heat, but I was able to accomplish the job with the Radio Shack iron. If I run across any other servo wiring job in the future I will more than likely buy this soldering iron.

You will do the same thing for the the connector that you add to the servo wires in the wing. Start by peeling back the tape that covers the wing wires by a couple of inches. Then lay the connector on the wing so that the pins extend past the end of the wing. Now cut your servo wires so they are the right length for your connector in this position. Then you will need to take an exacto blade and cut out a small area of foam so that the connector lays flush with the surface of the wing. Once this is done, strip back your wires, twist both reds together, both black wires together and then tin all four wires with solder. Before you solder the wires to your connector, be sure to slide a piece of shrink tubing over the wires prior to soldering them to the pins.

While this modification involves working with and soldering small servo wires which can be a bit tricky, in the long run I found the time invested to be well worth the effort. It's much easier to assembly and disassemble my Radian at the field.

P.S.
Here is a wiring diagram of the deans 4 pin connectors used in this mod. The colors reflect those found on the RP wing servo wires. The servo wires I used in the demo are Hitec extensions that are coded: Red(Positive), Black(Negative) and White(Signal)

Click Image for Larger View

Adding a External BEC to the Radian Pro

The Radian Pro comes with a Eflite 30A ESC that incorporates a 5.5V switch-mode BEC(battery elimination circuit). Rated at 700mA continuous service, many seem to think is not adequate to handle the servo system requirements. Even Eflite's own engineers state in their instruction manual that it "Drives up to 5 analog or 4 digital sub-micro-sized servos." The Pro has 6 servos, two ailerons, two flaps and of course the rudder and elevator. Also, I have seen where pilots with on board telemetry have reported current levels in excess of the .7 amp rating.

Reading the online forums it seemed to me that too many pilot's are reporting brownouts and lose of control of their RP's. If a new RP owner had received his plane with control rod linkage as binding as mine originally were, and he chose to fly it that way, he could have problems. The excess load caused by this binding as well as powering to many servos could overload the BEC and the next thing you know, they no longer have control of their sailplane.

Taking all this into consideration, I decided to replace the internal .7 amp BEC with a Castle Creations 10amp external BEC. The following video shows how I did this.



While this modification may not be absolutely necessary, it sure makes me more comfortable knowing I'm not going to lose my aircraft to a overload situation of the BEC.

Radian Pro E3B Connectors changed to XT60's

One of the first changes I made to the stock Radian Pro RC sailplane was to cut off the blue E3B connectors on the speed controller and solder on a new XT60. I found that while trying to disconnect the E3B that I nearly pulled the ESC out of the plane because it was so hard to pull apart.

I've switched all my RC toys over to these type connectors as I've found them to be much more reliable and of better quality  than both Dean's  and  the E3B connectors found on the stock Radian Pro.

Made from nylon and gold plated spring connectors that are installed during the injection molding process, the XT60 gives you a solid high amp connection that is perfect for applications up to 65 amp. 

I get mine off of Ebay from backbaycomputerguy. The connectors Chris sells are not cheap spin offs , but of the highest quality available and he will sell you just one or as many as you might want.

If you know how to solder, I highly recommend you try them, you won't be disappointed.

Radian Pro RC Sailplane Motor Problems

You may have read that the new Radian Pro is seriously under powered and that it has a motor problem. The Pro was advertised as having the same motor as the original Radian, just by exterior looks, this is not so. When the new motor has been run along side the old Radian motor hooked up to a watts meter, the new motor pulls 12-13 amps where the original Radian motor would pull up to 19amps. Horizon Hobby did some testing and came to the conclusion that the difference in amperage was not due to the motor but due to a manufacturing defect in the prop.

If you have a new radian and are not satisfied with the climb performance of your ship, call HH and request a new prop. In most cases this has fixed the power problem.

Horizon Hobby
1-800-338-4639