Almost done with my mods to this one. As willsonman pointed out... this wasn't really a conversion as there was an electric option available. This project turned into more of a ARF improvement rather than a full conversion. The model as shipped is solid but has several issues with hardware that needed to be addressed.
Landing Gear - Largest area of complaint was the landing gear being very susceptible to damage. To address that:
- Latteral and torsional basswood supports were added to the attachment plate for the mains. The gear is made of two aluminum sections and a common issue was the plate splitting in the middle. The latteral supports should address this, and the torsional supports should make the gear less likely to pull out. I will grab some shots of this tonight as I forgot to take pictures.
- Axels on mains were terrible. Hangar 9 used a threaded bolt as an axel with nothing to protect the wheel from the threads. Multiple people have had the wheel hubs chewed up by the threads after normal usage (see picture). I replaced the axels with REAL 5/32 axels cut to fit the wheel pants.
- As I fly from a grass field I wanted a bit larger wheel. I swapped in some light weight 3 1/4" wheels to replace the 2 3/4" that Hangar 9 used. This required cutting a bit from the wheel pants for clearance. The before and after pictures show the difference. It is subtle but the weight change was minor and the new wheels should play nicer with our field.
- Tailwheel had to go. This tailwheel setup had a tab into the aft fuse and was directly connected to the rudder. Many others reported replacing this tailwheel after only a handful of flights, and some had damage to their rudders. I installed a light ply plate that will fit the CF tailwheel support from the wreckage of the Pitts. I just need to pick up a 1/8" arm and hook up the springs to the new bracket burried in the rudder. Changes the stance on the ground a bit but will hold up a lot better to the grass field.
Power System - I'm going with the system that I pulled from the Pitts, which is just a bit different than the recommended Power 60.
- I was pleased to find the included mount would fit the motor mount for my Scorpion motor. I just needed to add 1/4" standoffs to each end to clear the cowl. I was expecting to have to build a new motor box but got lucky.
- The design for the electric version of this model calls for instaling the ESC on the underside of the battery tray, inside the fuse. This area gets efectively NO airflow and this seemed like a really bad idea to me... Strap the hot ESC to the bottom of a Lipo and give it 0 airflow. I used a sharpie to "paint" the bare wood underside of the motor mount/firewall black and then mounted the ESC on the outside of the firewall. In this location it is exposed to tons of airflow and is right above the exhaust port in the cowl. Should work perfectly.
- Cut a few CF spinner and balanced the Xoar prop. This setup took a fair amount of ballancing but is ready to go now. I know 2 blade is more efficient, but I really like the looks of the 3 blade and I already had them
Hardware - Another common complaint was that the pushrods and linkages were poor for the cost of this kit. I replaced all the included hardware with ball links and more solid wire. There is 0 slop in any of the linkages and they should hold up to anything. The kit also included an Aluminum wing tube. Some have seen this deform over time, and it is a bit heavy. I have a CF replacement tube that I'm going to test out. I'll know tonight how that works out.
Still need to get her on CG scale once the new wing tube and tailwheel arm are installed, but ATM the weight looks like it will be right at 8lbs. I would have liked to be around 7 3/4 but I'm happy with the modifications. With 12 lbs of thrust she'll still have 1.5:1 thrust to weight. Hope to get her in the air next weekend!