# Zenith CH750 build...

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#### Taiser

##### Well-Known Member
Once the skeleton is final drilled and riveted together then the bottom skin and nose skin gets fitted...

Skins clecoed together...

Then the nose skin gets pulled back with the straps and once you verify everything is snug you drill through the holes in the skin into the spar. This part is an absolute NIGHTMARE to do!!

Top skin is on, now everything gets final drilled to their proper size...then it all comes apart!

#### Taiser

##### Well-Known Member
Priming...

Skeleton mating surfaces are all primed with zinc chromate...

...and so are the skins. The middle of the skins have "L"s installed to stiffen the skin and stop the "oil canning" sound. Once it's assembled I will spray the entire interior of the wing with zinc oxide.

#### Taiser

##### Well-Known Member
Bottom skin is riveted on...

With the bottom skin riveted on I start planning on installing the fuel tanks, wiring for the strobes/nav lights and fuel lines...

Another view...

A shot showing the edge length of the wing. When you rivet the wing you have to make sure the main spar is at the same level across the span or you will introduce a twist in the wing. If you use saw horses the wing won't be 90 degrees but even if it's set at 70 just make sure it's 70 across the entire span. I used a digital level (indispensable for this) and my span was within .3 degrees across length. Was pretty happy about that.

#### Taiser

##### Well-Known Member
Flaperon brackets are installed. They are attached inside to the ribs. They are pretty beefy chunks of aluminum.

The bottom trailing skin is attached and riveted to the bottom rear spar. Once the flaperon arms are attached you measure the gap between the edge of the trailing skin and the top of the flaperon arm. Then secure the skin with tape and drill into the rear spar through the pre-drilled holes in the trailing skin.

#### Taiser

##### Well-Known Member
Installed the LED nav light into the wing tip.

#### Taiser

##### Well-Known Member
A few things done today....

I had a few hours to spare to day so I was able to get a few things done. First off I was able to get the stupid hummingbird out of my garage, but not before he crapped all over my wing!!! :uzi: I don't know how such a small bird can make such a mess! Anyways I was able to spray the wing with zinc chromate...

Lots of builders are worried about the weight added by spraying the interior of the plane completly! I don't get that. A gallon of my primer is about 10 lbs and most of that will evaporate! I've so far sprayed the fuselage, rudder, stab, and elevator and still have over 1/2 gallon left! Even if I used it all and it did not lose any from evaporation it's only 10 lbs to make sure you don't have corrosion in the plane!

Shot from the other side. You don't need a ton of this stuff, just a light coating.

#### Taiser

##### Well-Known Member
Then I was able to wire in and solder the wing tip light. I drilled holes in the nose ribs and installed grommets to run the wire to the wing root area.

I'm using 3wire shielded cable for the lights, which is what the instructions recommend. I grounded both the light and the shielding on the cable to the same point on the spar. All the connections are soldered (even the crimps) then I added heat shrinked tubes to protect the wire.

#### Taiser

##### Well-Known Member
And the last job of the day...

I started rough fitting the fuel lines in the wing. I'm installing a fuel shut off in wing with disconnects at the fuselage. I want to be able to take the wings off in winter for storage and to make maintenance easier!

#### Taiser

##### Well-Known Member
Alright y....just came back from a week long reunion with old high school buddies. We go to one of the buddies cabin every year to fish and drink (mostly drink) and reminisce but now I'm back! Didn't get much done this week-end (still in boozing recovery mode) but my new toy was waiting when I got back and I wanted to try it out...

Ordered this soldering gun on Amazon. Was wayyyy less on line than local but still cost over $200 bucks!!! I have a cheaper one but I wanted a lot more control on the heat, especially when I start working on the avionics behind the panel. Started by soldering the connection at the wing root. Here's the wing root area. I want a quick disconnect here because I want to be able to remove the wings in the winter for storage and trailering. The strobes come with a quick disconnect but it's the flimsiest, crapiest thing I have ever seen. I looked around for a better system but couldn't find it so I went to the local automotive store and bought a 4 prong trailer plug. Wires are a little bigger but it worked out fine. Heavy duty AND weather proof so I don't have to worry about the elements! The one that came with the$800.00 strobes would not have lasted a week!

So I dug out my spiffy "helping hand" and hooked it all up. ALL the connections are soldered, then shrink tube is placed on top of each connection, then a larger shrink tube over the entire area. Finally it's all wrapped in tape. Moisture should not be an issue!

All the wires individually shrink wrapped...

Then a BIG-ASS shrink tube to hold it all in...

...and the final product. It's not pretty but it's hidden in the wing, solid as hell and won't disconnect by itself like the flimsy one that came with the kit would probably do!!

#### Taiser

##### Well-Known Member
Just placed an order for a bunch of parts today. Ordered the adjustable seats, cowling and exhaust system for my motor that matches the airframe and cowl. Also coming is the Dynon D100 EFIS. All that stuff should be in by the middle of next week so I'll be busy again shortly. In the meantime I've been running fuel lines and trying to fit my forward top skin which is giving me problems... photos to come.

#### Taiser

##### Well-Known Member
So there is a wicked cold spell comming! Today was the last day of a warm stretch and I had only one wing left to cover with Zinc Oxide! I'm stuck working from last Saturday until next Friday so I stayed up late last night deburing the top skin and ribs on the wing. Today I sprayed the entire wing with Zinc Oxide! The worst is done, now the only parts I have left to build are the flaperons! Can't wait to get it inspected so I can start closing things up!

Here's a shot of the wing assembly before putting on the Zinc Oxide.

An action shot of me applying the Zinc Oxide...

and another one...

Finished just in time. The temp dropped about 5c when I was out there and the wind picked up big time. Good thing this stuff dries fast!

#### Taiser

##### Well-Known Member
Still tied up at work for another couple of days so nothing getting done. I did come home today and found a new present in the garage. Nice big box of parts...

Not a huge box but a good size one in any case.

A peek inside. Was well packed!

The first part that was dug out. Part of the cowl.

Parts laid out and inventoried. Exhaust, exhaust shield (for carb heat and cabin heat), sliding seats and assorted hardware.

Shot of the exhaust...

Sliding seats!

Hopefully I'll be able to tackle some of these parts on the week-end!

#### Taiser

##### Well-Known Member
Still haven't gotten much work done on the plane this week. Decided to put in a quick connect at the wing tips as well as the ones at the root...just in case I want to take off the wing tips for whatever reason. Will do that this week-end maybe. That also means I will have to install screws or something similar on the wingtips instead of easy to do rivets! It will add to the work load but worth it in the long run. Figure it will be way easier to paint the wing as well since I will be able to use a rotisserie to spin the wing while painting...something I couldn't do if I left the wing tip on!

OH and my Dynon D100 shipped today...can't wait to get it, but now I'm gonna have to do more work to the wings = $because now I have to install a remote compass, OAT probe and a Dynon Pitot so I can use the AOA feature. The Dynon will also limit my GPS choices if I want to use the GPS features of the EFIS since they don't all work with the Dynon. I got the Dynon for a great price though so I can't really complain! #### Taiser ##### Well-Known Member ****...was cold out yesterday. Next day in the shop I think the heater is going on... I started packing things up (motorcycles, riding mower, etc) for winter and getting the winter gear ready (snow-blower, tractor) but I did manage to fix up something that was bugging me. This was the original wiring I did for the wing tip strobe and nav light. Problem is that even though I left a lot of wire in so I could pop off the wing tip, there was no way to actually remove it. This was going to cause problems, especially when it came to painting the wing because I would not be able to put it on the rotissery, which makes painting MUCH easier, not to mention gives a better finish. Sooooo.. I decided to put in another plug at the wing tip. Un-soldered all the wires, put in another trailer plug. Wiring was a bit tricky since all the wire colors are off. Thank god I kept good track of all the color codes in my notebook. So I re-soldered everything up, put on the heat shrink tubes. These things are a pretty tight fit, but just to keep things secure I strapped on a heavy zip-lock, just because once the tip is on, it won't be coming off until inspection time or there is a problem! Side shot of the finished product! So now, with storage starting to get tight, even in my decent side garage, It's getting tight so I'm building a wing stand. Project for the day! #### Taiser ##### Well-Known Member Good day today!!! Got lots done.... Got the wing stand completed. GREAT design I found on the web and it was then improved upon by Mark Townsend, of Canadian Can-Zac fame. Took about 2 hours to build, including the scrounging for all the parts. Works great and is solid as hell. Got one wing on it and it's sits rock solid! No feeling that it's going to tip at all! A shot from the other side! The nose just sits on the two straps and the wing leans back on the top of the stand. Made the entire thing from parts of the crates my kit came in. I bought the fattest straps I could find, used for towing, they are about 3 inches wide. It's the only part I had to buy and it cost 40 bucks. Ooooooooo....shinny...... I prepped the second wing for work tomorrow. I have to install the attach points for the struts and jury struts. Once that's done I will flip the wing and do the fuel lines and electrical for the nav/strobe lights. Then I'll now be able to store both wings on the stand which will give me lots of room in the garage again! Tomorrow will also be "Garage Clean Up" day. It's gotten to be a disaster in there! #### Taiser ##### Well-Known Member Had a few hours this week-end on Saturday (thank god) and got a few more things done on the passenger wing... Installed the strut attach points and jury strut attachment brackets. Closer view of the main strut attach bracket. The "L" goes from front to back to distribute the load. Close up view of the attachment point of the front bracket. Shot of the jury strut attachment points. The rear attach point for the jury strut. That was it for the day, just a couple of hours work, but now the bottom wing is done! Last edited: #### Taiser ##### Well-Known Member On Sunday I got the wing flipped over and installed the strobe/nav lights on the wing tip, drilled the holes in the ribs for the grommets and ran the wire! Soldered the plugs and installed the lights in the wing tip! Ran the wire through the grommets and to the wing root. Here's a short video of the lighting test. Tested the strobes and navs using a 9v battery. Video is deceiving, the lights are much more bright in real life than my crappy camera was able to record! Nav and Strobe light testing... - YouTube Last edited: #### Taiser ##### Well-Known Member Hey Hey... Work went nuts again and I was busy as hell for the last few weeks. As of a couple of days ago though I've been off for a week (thank god) and was able to get a few more things done so far...and had a few issues... First off that god-**** humming bird was back! Now he's pissing me off!!! I think he's attracted to the red cord and handles used to open the doors when there is a power failure. I would have thought the **** things were hibernating or buggered off down south or whatever hummingbirds due in the fall...stupid birds! Anyways I got the thing out after an hour of messing around...but next time no more Mr. Nice...the BB's coming out (JK)! :whistle: So I had some issues with Aircraft Spruce. They were insisting the exhaust gaskets I ordered would NOT fit on my engine and sent my last order without them...? WTF? They did leave me a nice phone message to call them back to get the proper part. Hmmmm... Having worked on these engines for years I was pretty sure what gasket was needed. So I phoned them up and they said that there "supplier" advised them it would not fit... After double checking and finding out that it was indeed the right part number they were still hesitant. It wasn't until I got pretty annoyed and told them that every two studded Lycoming uses the same gasket that they finally shipped them to me...AT ADDITIONAL SHIPPING EXPENSE!!!:cry: You would think that after all that and it was there mess up they would send them for free (since I would not have paid more for shipping on the original order) instead of the 12 extra bucks I was dinged for$30 of parts.

So the new gaskets come in. Here's a shot of the old one and the new...look pretty close to me...

#### Taiser

##### Well-Known Member
I wanted to get rid of the exhaust, since it's sitting on my work table taking space...and I don't want to knock the thing off the table and possibly wrecking \$2000.00+ of stainless steel. I went to work on the engine prepping the exhaust stacks when I ran into another problem. Some idiot (or lazy) A&P obviously noted an exhaust leak and instead of popping off the exhaust and replacing the gaskets obviously just dropped the stacks and squeezed in some silicone in there to seal them!! :mad2: Nothing worse than a lazy ass mechanic!

So I had to go every exhaust port and get rid of all the high temp silicone used on the mating surfaces. That took a few hours. Used a dremel tool with a nylon brush wheel on it, some acetone and a nylon pad! Who says building isn't fun. Guess it happens when you buy an used engine!

Got most of it off...by the time I was done it was all gone.

Installed the exhaust stacks. When I took the old exhaust off some of the studs came out with the nuts. Don't want to re-use those so I put in new stainless steel ones in, along with some spark plug anti-seize compound. I have enough studs to replace them all, but last thing I want is to snap a stud...been there, done that...NO fun. So I left a few of the old ones in.

Close up of the stack.

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