Byron Cap 21 80" E-build

Revy

K, letsgo!!
I did this build last winter and had a build thread elsewhere, but I thought I would contribute it here.

At the last event our club hosted for the year in '09, a local had brought out a Byron Cap 21 kit NIP to sell. It grasped my attention immediately as I wanted to get into gas and giant scale. The price was right and after a bit of hummin' and hawin', I bit. It's a giant foamy!! It was packaged 22 yrs before and all of it was still the way it was from the factory.

Searching for a power plant, I was mortified at what can happen if any gas was to get on the foam. I saw a beautiful Christen Eagle that ended up as a pile of goo as a result of a burst tank. Gas was out, an e-build was the way to go for this kit.

I chose the E-flight Power 1.60 and a Castle Creations 110HV ESC on 10S. I know the ESC was a bit overkill as the 85 would have sufficed, but I like a bit of headroom when it comes to ESCs as I've experienced brownouts and they aren't fun.

The 10S batteries I saw were outrageously priced, but then HK came to be and I scored 2 x Zippy Flightmax 5S 5000mAh 40C for $150 shipped.
 

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Revy

K, letsgo!!
The construction had a couple modern touches implemented such as carbon spars instead of the wooden ones in the wings and the aluminum ones in the H-stab, variation on servo placement and most important was the new motor box. I also had to figure out power distribution.
 

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Revy

K, letsgo!!
My intent was to run the Rx off the main packs to keep the weight down, but I got a bad CC BEC Pro and it went "Pop!" after a bunch of systems tests frying 2 of my HS5625MGs. That forced me to go a separate battery for the Rx. CC was good about about it. As a matter of fact they not only replaced the BEC Pro, but gave me another 110HV in lieu of the servo loss. Very cool.

The main packs were placed where the tank would normally go and can slide back and forth to adjust CG. Those packs alone weigh 3lbs. Wedged in with foam up front and 3M Dura-Lock to secure. I used EC 5's for connectors to help with the 40V bolt of lightening that will hurt if allowed to contact skin, lol. There is a good spark when I plug in the arming plug. It is on the positive circuit in between the main packs and ESC.
 

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Revy

K, letsgo!!
I covered the Cap with 3/4 oz fiberglass cloth and West Systems epoxy with the intent to paint rather than cover as I was afraid of the heat melting the foam. The long cure time helped here big time.

I also tested out the paint on the cowl. I chose the Murdy scheme as it was turning out to be my scale entry. I went with a latex paint for base and a water based Varetane top coat.
 

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Revy

K, letsgo!!
Well after all of the painting was done I realized I was a bit impatient with the process. I should have left it dry completely between coats as some wrinkling was evident after I shot the Varethane, pmo. A misinterpreted instruction, argh. But I wasn't too upset with it cuz if you stood back 5 feet, it looked awesome!

When I had my final assembly all done and time to CG it it was way tail heavy. I tried everything I could not to add too much weight to it but I needed a lot of nose weight. The closer you put it to the CG the more you need so I tried to put it as far forward as I could. I ended up with a pair of hockey pucks slung out next to the motor itself! Least amount of weight added to balance and they are a conversation piece too, lol!
 

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Revy

K, letsgo!!
I had a couple of tests to make sure everything was in order. This video has the BEC Pro before it blew. The prop was a 20x6, not a 20x8.

[ame="http://www.youtube.com/watch?v=x4a7EoPQSAw"]http://www.youtube.com/watch?v=x4a7EoPQSAw[/ame]
 

Revy

K, letsgo!!
Not the maiden flight, but the second.

[ame]http://www.youtube.com/watch?v=UUPuUBWiaXQ[/ame]
 

Revy

K, letsgo!!
I now have an APC 20x11 E prop and boy does it pull! I cruise around 1/2-3/4 throttle for 10-12 minutes with scale aerobatics. More than enough grunt to haul this 16 lb AUW foamy around. Might do a re-coat this winter to see if I can clean up the looks a bit! ;)
 

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Chad H

Passin` Gas
Hey thanks for sharing that build and vids.

Man Byron Origonals. What a empire that was. You done a fantastic job there. looks sweet, sounds cool, and flies scale.

I have a NIB Byron Corsair with retracts I had given to me from a guy getting out of the hobby about 8 years ago. Its such a tempting build sitting there. Maybe some day.

The CAP 21 brings back memories I tell yah. Heres a pic of me and my Great Planes wood one like over 25 years ago...lol.

That is about the most beautifulist flying field I have ever seen. Just gorgeous. I hope more from down south view that video ans see how nice it can be up here.

Nice job Revy.
 

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BRUTUS

Plank Junky
Lifetime Supporter
Great thread- I've never seen a kit like that one. Love the hockey pucks you crazy Canuck!

I love your flying field beautiful!- I bet it's about under snow now too!?
 

Revy

K, letsgo!!
Thanks for the compliments, guys. It was my first kit build completed. I started one prior, CG Ultimate 10-300, but quickly realized I didn't have the skill set to build it properly. This was my initiation sort of speak.:)

Nice Cap, Chad!

The field is still all grass!!;) We won't get snow till the end of this month usually. Snow up on the peaks and creeping down, but nothing in the valley floor yet!
 
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