# Quicksilver MX Sprint II Project

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#### Chris In Marshfield

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Group photo! Last of the steel parts brushed off and ready for paint.

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#### Chris In Marshfield

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And that’s that. All done painting the steel parts. I’ll continue to clean the trike while waiting for new bolts to arrive.

#### Chris In Marshfield

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Over a few days, I installed the exhaust and flipped the gearbox for best thrust line.

#### Chris In Marshfield

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Mondo parts shipment arrived today. Full fastener kit, 4-points harnesses plus brackets (one harness on backorder), most of my flying wires (not all have been made yet—they’re made on demand), and a new main axle (found damage that can lead to cracks). Now I can make some MVP: Major Visual Progress. Approaching the “90% done, 90% to go” phase.

#### Chris In Marshfield

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Remove, clean, inspect, refinish, replace, torque, mark, repeat a gazillion times. Well, maybe not that many…

Root tube done and dusted. Will start the trike tomorrow. That’s when things start to look like an airplane.

#### Chris In Marshfield

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After a couple of weeks off of my Sprint project, I came back to working on the trike. Remove bolts, clean, inspect, replace with new, and torque to spec. Now that I’m working on the tubes, I have to be careful not to distort them by over tightening. Thanks to a fellow QS flyer for making me think twice during these activities!

#### Chris In Marshfield

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Not long ago, I made a jig to help with drilling the axles for Black Max brakes. The first turned out okay-ish, the second not well at all. There was just too much play with the soft wood and trying to do this with hand tools. There had to be a better way. So I reached out to Keith at Free Bird Innovations for another pair of axles and bushings. And then I called Miss Kim at AirTech and ordered a new axle tube.

With new parts in hand, I pondered my improved approach. Using a vice with my drill press, I set every axis loosely and lowered a 3/16” drill bit into the hole of the axle bushing allowing all surfaces to self-align with the bit. Once everything was aligned, I tightened every axis and triple checked everything was traveling smoothly without binding. The bushing is now the axle drill guide.

Next I inserted the axle, ensuring it was aligned with the key way 90° from the bolt hole so the brake caliper would be on top of the axle when installed. I dropped some cutting oil in the hole and started drilling the axle shaft slowly with a *brand new* drill bit. I think I held my breath the entire time I was drilling. It costs me $100 every time I have to do this! So far I’m out$200.

Once I punched through the other side, I started breathing again and loosened everything up, cleaned up the chips, and held my breath again as I turned it over to see the other side. Be still my heart…. It was perfect!

I cleaned up any burrs, inserted the bushing into the axles, bolted it, and torqued to spec (no threads showing).

I’m now recovering from the stress of this and enjoying a cold Coke in celebration.

#### Chris In Marshfield

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I got the Sprint on its own feet today. Clean parts are happy parts. And they’re even happier with new hardware.

#### Chris In Marshfield

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Worked on the control systems today. The control stick needs some modifications. Since it came with cable-operated band brakes and I installed hydraulic brakes, I need to remove the brackets for that in the stick. So I did the rest of the things.

The elevator trim bungees were a lot of work. Manual said to use 1/4” cord. It barely fits in the doubled-up side. But with some perseverance and four hands it got done. Fun with knots and heat shrink.

#### Chris In Marshfield

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Got the rudder pedals and control stick installed and aligned. Rudder pedals still need mechanical stops so found a surplus tube for that from a friend.

Seats are in as well as shoulder harnesses and have a couple of throttle parts waiting for paint to dry. Starting to run out of things to check off the list for the trike!

I ordered a few engine accessories like throttle and fuel pump brackets along with rudder pedal push rods for steerable nose wheel.

Installed the hydraulic brake handle and got the brake lines preliminarily run.

#### Chris In Marshfield

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Last couple of airframe parts came in yesterday so with the exception of a control system guard, all parts are on, aligned, and the trike is complete! A few engine brackets also arrived for throttle and oil injection pump so time to get moving on the engine completion.

Oh, and need to clean the bird poop off of my seat covers. Hangar robins are a feisty bunch.

#### Chris In Marshfield

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To accommodate the air box/intake silencer I reclocked the starter. It was easier than I expected it to be. I reassembled it with Loctite as suggested and everything fit as it should.

I was trying to put together the throttle cables off plane but it just wasn’t working out. So while I wasn’t sure I wanted to put the engine on at home (instead of the hangar), it kinda forced my hand. So now it’s up and mounted and the throttle/oil pump cables are connected. I admit I uttered an angry phrase or two while assembling this contraption. There are still some alignments to do and it may take a bit of gymnastics. But tomorrow I’ll bust out the Rotax installation manual and see if there is a secret handshake.

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#### Chris In Marshfield

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#### Chris In Marshfield

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Did the rough sync of the carbs today. It’s a tough activity to complete by yourself. Recruited my son to help me for a bit. Two sets of eyes are certainly better than one in this case.

#### Chris In Marshfield

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Got some prep done for the EIS harness on my Sprint project. To save myself a bit of time identifying wires, I labeled them and isolated the unused ones to get them out of the way. I got them into the shell and tied them up just to keep them together and keep the labels from sliding off. The labels are still easy to see even though they’re bunched up in the photo.

If you do a lot of wiring, this little Epson labeler from Amazon is a great tool. You can buy rolls of heat shrink for it just like label tape and print directly on the heat shrink. Well under \$100US and worth every penny!

#### Chris In Marshfield

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Worked on the instrument pod panel today. Got a little more work to do (one more switch and labels), but happy with the results. The plane came with a rotary ignition switch, but LEAF mentioned that they can be unreliable and recommended toggles, which is what I’ve done here. Not the two in the middle are reversed compared to the others. To shut off the Rotax ignition you have to short it out, hence the switches closing in the off position. I also retained the push button start switch.

#### Chris In Marshfield

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Finished wiring the panel after a few days’ wait for some parts. Ready to get the thing in the pod and get the wire pulled to the back of the plane.

#### Chris In Marshfield

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First fit to see if the cable length is right. Bought some braided nylon wire sleeve in blue and black from Amazon to match the color of the Quicksilver tubing. I think it adds a bit of pizazz compared to the usual black plastic loom, and it’s as flexible as the wire. I may change it to a more direct route instead of snaking the tubing. That takes up at least two feet of length. But first round looks pretty snazzy. I need to get some rubber edging to go around the front lip of the pod. It looks a bit unfinished.