Building a Sparrow

Wiplash

Todd Noble
Joined
May 7, 2009
Messages
366
Location
Hudson, IN
Aircraft
Air Command 582 LowRider w/stab
Total Flight Time
Gyro - 101 as of 7-10-16
Had a pretty productive first day.

Assembled the wheels.
Mains went together well. Front tire wouldn't hold air. Disassembled it and found a puncture in the tube with a something hard in the hole. Didn't remove it in hopes that the tube would be refunded or replaced. There was also something rattling inside the tube. Neal had a spare so put it back together and it held air.

The holes in the cheek plates were predrilled so that left cutting drilling the tubing.

After deburring the tube ends and drilling and deburring the holes, assembly went pretty quick.

I'm building this as an ultralight so that 254# limit is always on my mind. The Mast and Axle is redundant 1"x2" and the Front and rear keels are 2"x2".


The plan is to get it on wheels next...


:whip:
 

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Good Luck, hope everything goes well, I enjoy these build threads.
 
One of the most enjoyable phases of a build is the fitting of the first few parts and is only rivaled with the first flight! Best of luck with your build and thanks for sharing.
 
I pondered over the extra weight of the redundant mast and axle. But went with strength over weight.

Which brings me to a thought I had a few weeks ago. Why isn't there an extrusion available in 2x2 with a wall down the center?

If a die cost $1500 to $2000 it couldn't take that long to recoup the cost of the die could it?

You'd save weight and it could be priced below 2 pieces of 1x2.

Any thoughts?


:whip:
 
There used to be some tubing with a rib down the middle. It was popular with ultralight builders in the 80's for tail stock, but it didn't sell well enough and only stayed around a little while. I had heard that it came back a little while ago, but it could just have been some old inventory showing up on eBay.

*JC*
 
It would defeat the purpose of the redunant tube as a crack or break would just spread. the single 1"x 2" tube is so if 1 was to crack, the other tube would get you down.

if I remember right at one time aircommand sold a mast that was a 2"x2" box with a rib down the middle.
 
Fair enough.:yo:

:)
 
one thing you have to admit, Neals machine work is top notch. only draw back I found with my Falcon kit is no construction manual. but on the same note, since I installed an EA-82 with redrive and a taller mast with the Body encloser, mine has been alot more drawn out.
keeps us posted on your Build.
 
Yep, alot of CNC machined parts and all cuts and holes get finished and deburred.

For this build I have the advantage being an hour away from his shop. Which is where the gyro is being built. I get to be there to do some of the chopping and hole punching. It slows Neal down but he's ok with that. The proper equipment makes all difference. And who needs a manual when I have a Neal :).


So...
I changed shifts after the 4th of July Holiday. Took a couple weeks to adjust from 2nd to 3rd shift and I'm not really there yet.

Headed to the shop Friday and now this contraption is starting to look something.

Got the wheels mounted, lower struts and the motor mount cheek plates attached. The motor plates aren't in their final resting place yet because I and haven't decided on which engine to go with.

Probably work on the seat braces and instrument pod next.

:whip:
 

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That looks nice,thats a bigger tail wheel then mine had, also the wheels look nicer.

Neal does do some nice machine work for sure. pretty cool that you can go to his shop and work I bet that is alot of fun.

Tell Neal I said Hi.
 
What a bonus living that close to the shop, and having such easy access to the builder and designer. Wow.

Not familiar with the Sparrow but a nice looking frame and going together pretty quickly.

This one looks as though it might be a smooth journey through the build.

Looking forward to watching it go together
 
Great Pictures! Please keep taking and posting them as it is really fantastic to watch how they go together.
 
I sure do like that Airframe...very nice design.
A member of my local PRA Chapter is nearing completion of his right now...it's a nice ride that's coming together.
I like the simple and effective steering set-up...easy to construct and light.
My plan is to implement some of the features seen on these Airframes to my KB2 drop keel conversion (which is really turning into a whole different machine now).

I'd love to have access to some of that shop or one like it... I'm having a heck of a time with the hole drilling even using a drilling Jig. CNC makes life so much easier to allow one to focus on assembly, not stressing on minutia of drilling.

Nice work...please keep posting as many photos as you can...I enjoy "the build".

Thanks..
M-M
 
Yaw Mon, what Mike said...
 
Indeed! Pictures are a good thing!

It looks like you are moving along nicely. It is a good-looking machine.

Which engine do you plane to install?

*JC*
 
Thanks guys.

I upgraded the wheels, wanted something a little taller and cushiony.

Not made the decision on the engine yet. I'm leaning heavily toward the 503 but if a 447 came along for the right price it'd be hard to turn down. Also looking into HKS and Hirth. Considering my limited budget, it'll prolly end up being a Rotax in the end.
 
I know what you mean about the tires...that is a good choice.
I'm headed the same direction as you...I'll be using this new set of AirTrac tires on 6" rims for my KB2 drop keel (this old photo makes them look huge because they're closer to camera).

This frame is now being chopped for an 8" drop keel conversion...those tires with the new active suspension will make for a very soft cushion when landing due to the added weight of the heavy Subaru EA-82 going on the back.

M-M

PS...stick with the 503 (ask Tim Chick about His: http://www.rotaryforum.com/forum/showthread.php?t=21139)
...Hirth..BAD.
 

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Wow!

Now that's what I call cushiony... :D
 
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