n00bs Gonna Build a Carden

[rc4flying]

	Quote: Originally Posted by gareth.ky
	I guess I'm about 1/3 the way through construction in 4 weekends and I'm single so I have the spare time. I'll keep the pics coming.

You may not be single long if you keep those Home Depot visit up.......

Nice looking work on the plane, by the way.

[Fixed Wing]

	Quote: Originally Posted by gareth.ky
	I also noticed on the rudder that at some points along the edges the panels did not contact the foam. There wasn't enough glue to foam across the gap.

Gareth,

You're doing a great job. I know you'll be pleased with your results and how the plane flies.

Regarding the edges not gluing down properly for the future you may want to use toothpicks to press the sheeting to the foam core as shown in the attached picture.

I use Elmer's Ultimate glue which is very similar to Gorilla glue like you are using. This glue typically penetrates 3 to 5 beads of foam deep. In other words when you try to peel the sheeting away from the foam after the glue has cured you'll see about 3 -5 layers of the foam beads still stuck to the sheeting that broke away.

I also use a small paint roller to spread the glue onto the skins. This method seems to spread a more consistent layer of glue and in a smaller amount than the credit card method. I have been measuring about 1.5 -2 ounces of glue in a small jello shot cup and applying that amount to each skin for a 40% sized wing.

Keep up the good work and keep the pictures coming. We are interested and do appreciate it.

Dean

[gareth.ky]

Thats a good trick Fixed Wing. I found that on the wing panel where I trimmed the skins the edges had good adhesion. On the other panel I got ahead of myself and didn't trim them before I put the glue on. That panel will need some work to get the LE to stick down.

I didn't get much done this week. I just sanded down all the skins on the parts to the shape of the foam. I'm also working on cutting out some H-Stab root caps in light ply. These are for the anti-rotation mod that Walt does. It looks easy enough and thats how 90% of the ARF's work.

What kind of filler do you all use?

Oh and one other topic; Shop Heat. Being a Caymanian I'm new to working in the cold like this. I had to go out and get a Kerosene heater for the garage. It was just too cold in there to work. some of the glues and stuff down work below 40 degreed F. I feel like a hobo every time i go warm my hands over it but it really works well! What do you all do for shop heat?

Shop Heat.jpg

[mark786]

Gareth,
Good job on the build. I originally tried light ply for the stab root ribs but found very quickly that it wouldn't be enough. I made another set out of regular ply and threw away the light ply set.
Mark

[gareth.ky]

	Quote: Originally Posted by mark786
	Gareth, Good job on the build. I originally tried light ply for the stab root ribs but found very quickly that it wouldn't be enough. I made another set out of regular ply and threw away the light ply set. Mark

Sorry, yes what I have is birch ply, 1/8" thick if I remember. Good Catch.

[gareth.ky]

I still haven't decided on the motor for this project. I've narrowed it down to one brand and two choices. The DA 100 or the DA 85. I'm assuming that either setup would run on canister mufflers so the cost and weight of the canisters factors into this.

The case for the 85 goes something like this:

• The 85 is ~$500 cheaper than the 100
• The 85 is 1.8 pounds lighter than the 100
• It makes almost the same power as the 100

If you believe that a stock built 260 with a DA 100 weighs about 28 pounds then it will weight 26.2 pounds with no mods and a DA 85. I'm committed to doing some further lightening of the airframe, mainly in the motor box as others have done and a CF wing tube and routed out landing gear (if I can find someone to do it). I'm going to do A123 batts with a really simple setup, no regs and no power box. I'm going to do Walts mod and put the rudder servo in the base of the tail.

I'm hopeful that I can hit 25.5 pounds.

That said I'm still a little worried that the 85 will be underpowered. Everyone I have talked to says I shouldn't be. The 85 is going to have other down sides:

• Balancing the airplane will probably require cutting holes in the tail surfaces. It may even need weight.
• I'll have to butcher the pretty cowl
• The 85 is noisy and might not be IMAC legal with the optimum prop.

If you have any input on the engine choice please post. I need to make my mind up by the end of the week and place an order.

[Greyhoundman]

This is just my opinion, but if you go with the 85 you will want as much weight out of the tail as possible. You might need to lighten up the tail feathers and will definitely want the rudder on pull pull. I guess having a canister might help the cg a little but not really sure about that.

[gareth.ky]

Your right, I need to get the CG correct and I may have to settle for pull pull. I would rather have tight direct connections. With the push-pull setup 1 5955 is probably enough and the 8711 will certainly do it. I would rather cut up the tail feathers than do pull pull. The servo is about 2oz so I'd need to find 2oz at least to take out.

I could also, maybe, do a push-pull with carbon tubes and the servo up front.

Batteries will probably be mounted on top of the motor box like a 50cc.

[Neil4]

I was in the same sort of boat as you are with engine choice for Carden. I am building a 35% Dalton 260 and I was debating between the DA 100 and DA 85. I went through the pros and cons of each one and went with the DA 100. I choice the 100 because with the more weight of the 100 in the front would allow me to run a direct link to the rudder along with getting the CG right without lightening the tail surfaces which I liked. And yes as you know you will have one more canister over the 85 and that will cost a little more oviously but you will know for a fact that you will have enough power with the 100. AS you said i was worried about 85 being under powered so I went with the 100 just to be safe because you wouldn't want to buy the 85 to find it wouldn't cut it.

Oh, by the way I heard you mention going with 1 5955 for the rudder...don't do that. Go with the 8711, much more holding power. I had i 5955 in my 33% Yak 54 and it would not hold a knife edge half way through the flight. Switched to an 8711 in the rudder and it was like night and day. But go with the 5955 everywhere else, at least that is what I am doing.

Neil(sorry about the long post)

[gareth.ky]

No problem about the long post.

If the airplane was going to come out even just 1 pound lighter, like the Dalton, I wouldn't be worried about using the 85. I have read lots of positive reports of the 85 on airplanes from 22 to 25 pounds. Over that there isn't much info. Someone suggested I could buy it and then swap it out for a 100 if its too little power. The bolt patterns don't match so a swap would not be straight forward.

The rudder may need an 8711 but I'll try the 5955 first. I have seen the new Hanger 9 260 flying on a single 5955 mounted in the tail and it got checked out by a very good pilot. If its found wanting I can always swap servos, much easier than swapping motors.

[gareth.ky]

Trying to get this build back on track. First I had to fix the screwup on the LE of the wing core. I forgot to trim the skins before I put the glue on them and the front didn't adhere. It didn't affect the wing structurally but the airfoil was going to be off so I had to try and fix it. I used a foam brush to apply wood glue and then taped it to apply pressure. I tried using the shucks but they couldn't apply enough force now that the sheeting already has glue dried on it.



I'll spend my nights this week attaching the LE and TE blocks and shaping them. I put in my order for the motor & canister, I'll wait till it shows up to say what I got. Tomorrow its on the the fuse sides.

[gareth.ky]

FYI, Horizon offers their catalog up through Amazon. So this is about the most convenient way to get Mercury CA, which I'm increasingly impressed with. The stuff is just so well mannered. The thin sets so fast it smokes. The Medium gives you more time but it sets and stays put. The time from application to setting is very consistent. And lastly the bottles don't clog up!