Installing wire bearings and rear hooks

A recent discussion on the Yahoo Indoor_Construction forum revealed the need for more tutorials on installing wire bearings and hooks in rolled tube fuselages, particularly for beginning F1D fliers.

What follows is my personal method. Some will find it too heavy, others too difficult. This is the reason why there are many different methods for installing your hardware on an F1D. The model used below is actually an F1M. I use the same technique for both, but F1M’s are much easier to photograph.

Let’s get started…

I begin with a motor tube trimmed to length but without any taper cut into the front. My bearings are formed to allow proper clearance on the prop shaft, both for length and spacing from the motorstick. Usually my webbing material is the same thickness as the motorstick wood. In this case, the motorstick is .017 C grain and so is the webbing. The bearing and hook are .025″ wire because I had the weight budget for it and didn’t want any flexure in these parts. Notice the slight notch in the webbing sheet. This is created by sliding the sheet against the front of the motorstick and pressing it in slightly to crush the wood there. This does crush the top of the motorstick slightly as well, but that part will be cut off later anyway. Use the notch to get the exact width of the webbing.

DSC05822             DSC05823


Cut the webbing to length and size as shown using the notch as a guide.


I cut three pieces of webbing. One for the bearing, one for the hook, and one for facing on those webs.


Use a small amount of CA glue to secure the bearing and hook to the webbing. This is not a place to try to save a lot of weight. These parts will be under extreme loads at launch torque.


Cut the extra webbing piece in half to get your facing parts and use Duco to secure each half onto its respective piece of webbing. I actually hold the part in my fingers, crushing the facing slightly into the wire to get a firm mounting. The duco will set fairly quickly and result in a permanent entrapment of the wire.


Cut a slot in the bottom of the motorstick the length and width of the bearing so that it can be slid into place. Hopefully the only bow in your stick is along the seam, and the stick should bow toward the seam. You can then cut along the seam and make that part the bottom of the stick. The bracing wire’s tension will pull the stick straight. You will also need to cut a corresponding slot in the top of the stick if your bearing protrudes out the top as mine does to form the mounting eyelet for your bracing wire.


Smear a liberal coat of duco on the top and bottom of the webbing. Do not delay here…


Quickly slide the web/bearing assembly in place with one smooth motion. Do not stop until it is all the way in or it will stick quite permanently! I’m sure you could put a thin coat of Duco on and reactivate it with acetone, but this method has worked well for me for the past 4 years of contest flying and doesn’t add enough weight to be a problem, even on F1R models where weight is critical.


Now you can cut the from of the motorstick to a slope right back to the bearing wire (meaning you need to cut through the webbing, too). Use a sharp, new razor blade to do this without tearing the wood!


Cap the stick off with some more webbing. This cap is critical to keep the stick from collapsing under load in this area. It also prevents your fingers from crushing the stick while loading motors.


Once the glue is dried, trim the webbing with a sharp razor and your front end is finished.


Now on to the rear hook. Mark the motorstick for hook placement, including the dimensions of the facing.


Cut a slot in the motorstick using these guide lines and a sharp razor. The slot needs to be wider in the region of the facing.


Liberally coat the edges of the webbing with Duco just like you did with the bearing, and slide the assembly into the slot, pushing the eyelet of the hook straight through the other side of the motorstick so that the webbing is fully in place. I press a finger against the stick where the hook’s eyelet will punch through so that the wood only tears in the exact point where the eyelet protrudes.


Now seal the slot with a little more Duco, add your hook’s gusset, and the motorstick is ready for wing posts and bracing.


Red Shift B/C Rocket Glider

In preparation for HHAEFI 2015, Joshua wanted to have a new rocket glider to demo for the attendees. Using the parts from an old Hugulet B handlaunched glider from the 1930’s, he produced this 18″ span fixed wing glider.


The new Red Shift B/C did not disappoint, flying right off the board with no adjustments other than a couple clicks of right aileron trim.

The Red Shift is a two channel glider, featuring aileron and elevator control in keeping with a pylon racing type flight profile. It is fully aerobatic with excellent pitch and roll authority and boosts completely hands off on the mighty Estes C6 engines. The wings have proven strong enough to easily handle loops at full speed and power.



Joshua is very pleased with the results; the short development time had him nervous about the success of this project, but the model has performed great for the crowds at HHAEFI and at the recent Mercer Robotics Club outing.

Speaking of that outing, here’s a video of the Red Shift in flight:



Mercer University Flight Demos

The Mercer Robotics Club visited SuperSod’s farm in Warner Robins, and J&H Aerospace was invited to demo a few aircraft. The club recently purchased two kits for the experimental Switchblade A/B, a higher powered version of the XP intended to allow rocket powered FPV flying.

Joshua Finn’s Smoothie made an appearance, putting up two very nice flights.

Jake Kutrufis, one of Joshua’s coworkers and an engineering student at Mercer, piloted the Switchblade XP for the first time. He is the first person other than the designer to fly this aircraft and had a lot of fun goofing around with it. Congratulations, Jake!

J&H Aerospace wishes to thank the Mercer Robotics Club for this fantastic opportunity and looks forward to our next outing with the club (hopefully in two weeks!).

Joshua Finn qualifies for 2016 F1D Team

Joshua and Hope attended the US F1D Team Selection Finals held at the historic Hangar 1 at Joint Base McGuire-Dix-Lakehurst. The senior team contenders entered into a stiff competition, and when the dust settled, John Kagan, Brett Sanborn, and Joshua Finn emerged as the top three, qualifying to attend the 2016 World Championship in Slanic Prahova, Romania.

Hope flew several models and performed excellently, drawing high compliments from the participants, but she chose not to make a bid for the team this year.

MERC carried this news article announcing Joshua’s achievement:

MERC Engineer To Represent U.S. In 2016 Indoor Free Flight World Championship

Reigning world champion Kang Lee caught this footage of the models — look closely for Joshua’s model bumping against the rafters more than 165 feet up!

Model Airplane Design & Components