RobT

My Feedback: (17)

As long as you coach me to take down Albert! From your build Paul it looks like there are going to be a few Extra 300's in NE Unlimited next year.

What is Chris going to be using as his ride?

RobT

My Feedback: (17)

I use the foam Dennis uses to protect the kit during shipping to make templates to find the aileron servo bays.

Drawing out the ailerons is straight forward. I use an angle finder to make sure the root of the aileron is parallel to the tip.

In the last picture you can see two pencil lines. The outer line is the stock aileron size. I cut at the inner line...

wgeffon

My Feedback: (4)

Rob,

Sorry to mutter up your thread with the stab stuff. This will be the last thing I say about it here.

All I was trying to say, and the reason we changed the mounting method on mine was because of the 3 planes that I saw go in last year each had the brackett broke in half. The plates holding the bracketts were not ripped out in any of these planes.
One plane had an anti rotation pin. The other two did not.
No stripped servos on any of the planes.
In all cases, half of the brackett was left on the broken fuse side and the other half was on the busted stab.
Can anyone ever say with 100% certanty what happened? No.
But, you can use some deductive reasoning and see what is comon to all three incidents.

If your comfortable using them do it.

CAPtain232

My Feedback: (40)

I would definitely agree that the broken L bracket will cause a complete failure. The screw through the stab tube would be located on the pivot point and would not be able to hold up against the torque created from the air blowing the stab up to a verticle position.


.......

I couldn't disagree more. While the design is good (airfoils, fuse shape, top hatch, etc.), they are OVER ENGINEERED as well. Carden kits are simply TOO BEEFY when built stock. All of the improvements that I make, or maybe better stated some of the pro builders, are GREAT improvements. We are, to some extent, redesigning what Dennis has done. Again, the basic design is good, but Dennis could (although I am sure he won't) implement them into his kits at his location.

RobT

My Feedback: (17)

Cap...that is one of the many things that is great about Dennis's designs. They can be built very strong or lightened a bit. Most people do not realize that a 40 lbs. Carden 330 has the same wing loading as a 36 lbs. aeroworks 300L (~35 oz per sq foot). Yet most people THINK the aeroworks is light and the Carden is heavy.

Back to the build...
A few days ago I laminated the 3/8 rudder L.E. and the Stab T.E. together by clamping them together with a coat of wood glue between them. These were then glued to their respective parts (again with wood glue) and this morning they were planed and sanded to shape.

jmiracle

My Feedback: (9)

I don't think anyone is saying the L bracket WON'T cause failure if it's the ONLY anti-rotation method used.

I think what others have tried to convey is if a simple wood dowel is added to the root of the stab, the L bracket is no longer the only point holding the stab in place.

The screw through the stab tube is just to keep the stab from sliding off the tube. The dowel prevents the stab from rotating around the tube....same function as the L bracket.m

It's a simple modification that adds very little weight....IMO, it should be added to the plans as at least an optional method of locating the stab on the fuse.

RobT

My Feedback: (17)

Here is another tip. I wasn't going to mention it because I thought it was just me being fussy, however after talking to Dennis today he thought it was worth mentioning, especially during the L bracket conversation. I mark each piece of the aircraft as left or right while I am building. This includes ailerons, elevators, and even the L brackets. I use a silver marker to mark on the fuse side of each bracket which is which. These L brackets are custom parts, and if they were switched, every time you tightened them down you would create a slight twisting force on them...this could lead to their failure.

RobT

My Feedback: (17)

After I cut the stab and elevators free I hold both stabs (and elevators) together as in the picture and sand them down. This gives me a good glue joint and ensures the elevators and stabs are exactly the same.

Dennis gives sheets of wood for things like LEs and TEs instead of pieces to ensure your right and left sides are equal weight. Note the layout. The stabs use the same sheet and the elevators use the same sheet. Do this on all surfaces.

zzw26n

My Feedback: (45)

Did not know that, thanks a million.

RobT

My Feedback: (17)

Which one?

zzw26n

My Feedback: (45)

The two stabs , the two elevators together, to sand so there exeactly the same, that was a good lesson for me.

Ward

RobT

My Feedback: (17)

This morning I drilled the hinge holes for the elevators and ailerons. Didn't take pictures, but I can do a mock up if anyone requests.

The method of installing Robart Hinge Points is very easy.

Lay out the locations of the hinges. For the elevators I just copied the locations Dennis gives on the plans. For the Ailerons I started one inch out from the root and put a hinge every five inches. The last hinge at the tip was 4" .

Using the Robart hinge jig drill the holes in the first surface. I then dip scrap hinges into some paint and install them into the first side. Align the mating surface and push them together. You have now transfered the hinge locations onto the second side. Now just use the hinge guide to drill the second side.

RobT

My Feedback: (17)

Did some foam cutting this saturday. Made a "Bow" by drilling two 5/16" holes at an angle at the ends of a 1'x2'. Inserted dowels into the holes. The dowels had 1/16" holes drilled in the ends to accept the hot wire. The hot wire was then strung between the two dowels and pulled tight. A 10 amp battery charger was then attached to both ends of the wire.

Then we used the setup to remove some material from the hatch and the cheeks. While we were doing this we lightened both the 300 and a 35% 260. Pictures are of the 260.

Rob

RickP

My Feedback: (2)

Rob,
I don't hold with the "Eyeballing" it trick to line up the vertical stab. Seems to me there could be a better way? Fixture of some sort perhaps? How do you line up the fuse and then keep it from shifting while you work on it?
Regards,
Rick

RobT

My Feedback: (17)

Rick,

Any suggestions on how to set the fin for the future?

All,

I have fallen behind on the posts, and the progress, but it is time to choose a scheme.

What are your votes / comments. Feel free to add others...

zzw26n

My Feedback: (45)

I like this one .............
picture no. 4, white top, red bottom.

Bobt2

My Feedback: (4)

but, what do the wings look like? #1 too much red #2 too much blue.

OnTheEdge

Take a look at these for some ideas:

http://www.airliners.net/search/phot...ords=Extra+300


There are pages of 300's. Click on the photo and then click on the photo again to make it huge.


Here's the one that caught my eye:

OnTheEdge

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RobT

My Feedback: (17)

Thanks Mark.

That is the site the pictures I posted came from!

RobT

My Feedback: (17)

Top of the wings for number 3....anyone have a better view?

Thanks

RickP

My Feedback: (2)

Rob,
I would think that some kind of fixture could be helpfull, but I really don't know how you would get the fixture perfect.
Rick

as722

My Feedback: (1)

I'll post a picture of a jig I made.

Albert

DMichael

My Feedback: (5)

Rob,

Some more considerations. Tim Webber has some nice schemes on his Extra. My wife's best friend used to date him and they remain friends. He had an Extra 300 and recently upgraded to an Extra 300s so there are a couple of schemes to choose from. Here's the 300.

Dave

DMichael

My Feedback: (5)

Here's some of his new Extra 300s.