n00bs Gonna Build a Carden

[gareth.ky]

What size should the bolts for the anti rotation pins be? Is it different on the elevator vs. the wing?

The manual says to use 8-32 which is what exactly?. This airplane is going to be metric. Any ideas on the stabs?

Ok, turns out the 8 in 8-32 is the size and its rough the same as 4mm. Thats handy because I know thats the smallest size blind nut that I can find in metric.

[gareth.ky]

Here is a diagram showing the dimensions of the standoff block. Here are the pics from Sketchup:

[gareth.ky]

I'm kinda stalled out on the build. There's are a bunch of stuff I need to do that I don't want to do. One of those "get things done" tricks is to write down all the reasons you don't want to do something. I need some of that right now. I find that there are big three reasons I don't want to do something:

• I'll have to fix or work around a mistake I already made.
• I don't have the right tools so ill have to 'improvise' something.
• I don't know the best way to do it.

I'm also going to get some pegboard for my workshop. It was really getting disorganized! Nothing sucks like not being able to find a tool because it buried under a pile of crap on a table. Work goes a lot smoother if the shop is organized.

[buttface]

Hey gareth.ky, Where can I get a cad file of the motor box cutouts for the 40%Carden Edge 540? Help.....

[yakwrecker]

Dude that motor mount is beautiful. I think the 85 is going to be perfect in this plane at 25lbs. Keep up the good work, besides you gotta catch up to me.
Jon

[gareth.ky]

Thanks Jon. Yes sir I need to catch up! I'm working on it.

buttface, I made the cutouts file custom for this motor box. I took careful measurements of the motor box parts and reproduced them in CAD (Google Sketchup). These cutouts probably wont fit your application but I'll post the file if that helps. I wasn't going to do it until after I flew the airplane because, who knows, the motor might just fall off!

[gareth.ky]

I need some input from some experienced builders on this. I need to put these end caps on the elevator. How best should I get that done? Should I just sand the sheeting off flush and glue on the end cap and then shape it match? If I stick it on with poly glue will that hold up in flight? Should I try to and make it fit in there somehow?

This is one of those things I don't have a good answer for so I'm avoiding doing it. I should have put them on before the sheeting but I didn't so here I am.

[mark786]

Gareth,
The most secure method would be to recess into the skins. With a gluing surface of the foam, stab tube socket and the skins it will be very secure. I also use an alignment dowel above the front bolt drilled and inserted in about 3". This adds another glue surface. That will l be plenty secure. I used Tightbond II. Since finishing the plane last month I have had a field box fall on my stab. It fell 4' from the shelf in the trailer. Bent the tube but did not damage the root rib or attachment.
Mark

[mark786]

I keep Walt's 260 and 300 build bookmarked. Here is Walt's, mine is very similar.
Mark
http://www.flyinggiants.com/forums/f...st75245-8.html

[gareth.ky]

Thanks for the reply mark786, nice looking 260!

I agree that inside is better. I don't know if its that much better though. Its 1/8" of skin really holding much of the load? Its a lot more work to do it that way after you put the skins on. I will try it tonight and see how it goes.

[mark786]

It's probably not so much about strength as it makes a better looking joint at the root when covered. Just like a lot of people are doing the same at the wing root. Just pretties it up some. Kinda hard to get the shape sanded without screwing it up when the sheeting is thin balsa and you are sanding the edge of ply.
I thought it was easier to sand the ply root to shape and then insert.
Mark

[buttface]

Great!

[gareth.ky]

I'm still working on getting the truss sides onto the motor box. Here is what I did this weekend:

• Attached F2, F3 & F4 parts to the motor box
• Added the motor box bottom
• Pinned the hardwood blocks with the 1/8" dowel (ran out and had to go to the hardware store!)
• Sanded and fit the truss sides to the motor box
• Cut the holes in the struss sides for the wing and tail tube sockets
• Applied LE & TE stock to the wings and rudder.

So far it looking really straight. The tube socket plates lined up just right and the level reads 0 on the wing tube. I still need to drill the landing gear mount before I can attach the sides to the motor box.

I mocked up the sides and at this phase I'm more worried about them being vertically straight and square to the box than I am about them being straight over the plans. I'm planning to use triangles to keep it straight and only use the aluminum angle when I'm building the truss bottom. One thats done its back to the triangles for the top. Should come out very straight and square.

Dan phoned in the winning solution to the problem with the H-Stab. Easy and simple . I'll post pics of that and should have them done this week.

[Spdstr280Z]

Looking good Gareth, I'm following along looking for inspiration since I'm in the same shape. I picked up an older 35% Carden Extra 300 kit a while back and I don't have much building experience. Right now I am working my way through a few smaller kits to pick up some experience and skills. I can already tell I need to improve my tools and work area. I haven't done anything yet other than sheet a couple of non-critical parts.

Keep it up !

Jason

[gareth.ky]

Yeah, the fuse sides are on! Here are pics from the weekend:

Last pic is me checking the tube socket is level. I bit premature but it all looks good

Tonight I drilled the holes for the gear. This was kind of a . You got this motor box and its wobbly and perched on the drill press and what do you get? Error:

Yup, the big hole was the first attempt. Way off the mark. For the other holes I went back in with a pin vise and drilled a pilot hole about 5mm deep as a marker. Then I went in with a small drill bit on the press and drilled a full depth pilot hole. Then I hit it with the big bit. All those holes were on target. I went for blind nuts and 4mm bolts for the gear. The blind nuts need to be cut off to fit:

Then I mocked up everything for gluing the fuse sides. When it was all done I found a small error where I had sanded too much off of on of the F-4 bulkheads. It actually tapers towards the table. Its not a huge deal, I used epoxy and milled glass for all the joints so the gap was easily filled. The point is that you should be able to find the error in your parts with whatever jig you set up. If your jig isn't helping you locate errors your stuff is perfect or its not a good jig. Everything has error in it. Find it, see if its acceptable, correct it if needed and move on.

(Don't bother cutting any holes in F-5. It only saved 2 grams, not worth the time.)