BOLT

Great forum!!!!!!

I've been building my SD since Febreuary of this year. I'm almost finish but need help in two items.
1. I read that the landing gear is weak. I have seen some pictures that show some sort of wire+wheel collars used for reinforcement but the details on how is done is
absent. Can some tell me exactly how it's done? (some pictures would be great).
2. I'm using a G-38 in mine which means that I have to remove practically all of the bottom cowl. Is the Fibreglass specialties a better option? I mean, do I have to do the
same amount of removal of material? I think I read somewhere that this cowl is a better fit for this engine.

Your response is very appreciated.

Bolt

nh4clo4

My Feedback: (33)

I have aG38 in mine with the stock cowl, It wasn't too bad, I can get more pictures if you want.

as far as the landing gear, You bend a 5/32" music wire to the shape of the landing gear, then use wheel collars and 6/32 screws, that go through the aluminum, into the wheel collar, and tighten on the music wire, it takes some filing to get the screws the right length, where they tighten to the music wire and the aluminum at the same time.
ED

WILDCRASHWILLY

Bolt,

Glad your coming along on you Decath. Look at post number 1433 and 1434 on I think it was page 58. I took a few pictures of what I did. Hope that helps.

On another note, I did some calculations and it looks like I need 9 oz of lead up front to balance. [:@] I don't have any so I going to run to a tire store this afternoon and get some lead strips that they use to balance mag wheels.

BOLT

Thanks a lot you guys!

I plan to incluse some pictures of mine soon.

dabrown

Bolt,

I'm in the process of replacing my Saito 180 with a G-38. As you did, I cut out most of the bottom to clear the spark plug, wire and cylinder head. Some was already missing from the Saito install so I could possibly fill back in a part behind the lower scoop. On the side I had to cut out about a 1 inch by 1 1/2 inch hole to clear the carb.

I don't think any cowl could enclose it all. The Fiberglass Specialties version looks like it might be a bit wider (?) so it may enclose the carb.

Overall I'm not worried about the open bottom and the carb is accessible too. (My G-38 is the B&B Specialties/Bennett version so yours could possibly have a different carb mount). I was actually amazed that the flywheel and magneto parts fit inside as well as they do.

Dave

Zor

Hello dand,

Those "terribly heavy" wing tips have a very short "moment arm".
Hollowing them would reduce overall weight but would have a small effect on the CG location.

Zor

Zor

Hi WILDCRASHWILLY,

The CG range is not always available from designers or manufacturers.
In your case you are quoting it as being 1/2" from 3 3/8" so the range is from 2 7/8" to 3 7/8" and you found your CG at 4".

If you know how these limits are established and what to expect as the CG approaches the limit either forward or rear limit then you will I imagine do the necessary correction.

If needed I can explain how the limits are established.

Zor

BOLT

Dave:

My G-38 is using the same muffler as yours. I changed the magneto to an electronic ignition, it gives me better idle and reduce a little bit of weight from the nose. I'll be using the stock cowl but plan to get the fiberglass one ( plus wheel pants) this Xmas. Let's see what happens now.

Bolt

[email protected]

Thanks for the clarification Zor, yes hollowing out the wing tips is intended to reduce the overall weight, knowing it will not affect the CG much. If I could hollow them out and remove the 8 oz in the nose by moving the servos forward, I could remove almost a pound of the overall weight. My plane as it is now has too high of a stall speed and removing weight would improve it.

flyathome

My Feedback: (7)

This is my Dynaflite Super Decathlon I just finished last month. It is powered by a DLA 32 and guided by an Airtronics
SD 10G. I am very pleased with the way it flies. The kit was very easy to build with no real problems encountered.

Steve

Kolbboer

Hi,
I have a G38 in mine, and i did not remove any material of the bottom of cowlat all.

(see pictures of original cowl)

Maiden flight:
http://www.youtube.com/watch?v=QvqYuCDdWhg


RGS
Jan

WILDCRASHWILLY

Wow,

30 to 40 MPH winds here today[X(]. Very unusual for this area. Needless to say, I'm not brave enough to maiden in this. Hope everyone is doing well. Lets see some pictures red_jeepster and Drube.

Red_Jeepster

Just finishing a project for Christmas. As soon as the shop is cleaned up, I will lay out the SD! No one has any info about going electric on this build, eh?

WILDCRASHWILLY

The only thing I've seen is Glow and Gas. Might check over on the F****gG***ts site and see if any of those guys have tried electric. BTW: saw the weather on the TV a few minutes ago, getting 49 mph wind gust today at the airport in Paducah KY which is about 18 or 20 miles from my location. about 5 miles from our club field.

Red_Jeepster

Getting set for the big winter storm here in PA. I will just stay with my plan for 35cc gas and smoke. Love the sound. Electric... What was I thinking! !!

dabrown

As I mentioned earlier, I've been retrofitting my SD with a G-38. See pics. Hole in top of cowl deck is to access mounting bolts. Fortunately it's covered by the cowling. Now I need to install the tank and plumbing. Been thinking about going with a two battery/two receiver set up. Would appreciate any comments on doing so. My purpose in doing so is to increase reliability through redundancy.

dave

Red_Jeepster

Dabrown, For what it's worth... I have been building and flying for over 30 years and never had seen really good reason for redundant rcvr set-up. Especially now (today) with the quality of receivers being provided by the big mfrs. I've never lost a plane due to receiver failure, only my mistakes and once a servo wire got rubbed thru and shorted, causing a pretty impressive crash. BUT, you are the builder of your own plane, and need to answer that for yourself.

My bench is now clear! I am starting the layout for my SD wings day after tomorrow! WHOOO HOOOO! My wife grabbed up all my bits on my Tower Wish List, and now they are in my hands - everything for the SD build.
Photos will come.

I won't consider monokote because of the plane. (not to mention I have become really disappointed in it over the last few years)
So I am planning on Coverite. Maybe Poly Lite from Stits.

Red_Jeepster

Tail feathers are started! No need to post pics, as nothing out of the ordinary was done so far.

nh4clo4

My Feedback: (33)

Keep at it, and keep us informed.

WILDCRASHWILLY

Hey guys,

With the exception of balancing, which I have'nt been in a big hurry about, due to the weather holding up any flying, I'm finished with my Decath. I am starting a new plans build thread for the Hot Hots, (link is attached) but, I will be monitoring this thread and commenting from time to time with you guys as I have really enjoyed the build once I got into it. In addition, I have enjoyed the friendships we have formed on this thread.

http://www.rcuniverse.com/forum/m_11347209/tm.htm

Thanks,

WILDCRASHWILLY

Hey Drube and Bolt,

Any luck with your Decath builds? Haven't heard from you guys lately.

Red_Jeepster

I've gotten my tail feathers built, sanded to shape and Robart hinge pockets installed. I will be installing flying wires on the tail, so I included the dowel plug in the vert stab.
This next week should see more progress. I just placed an order for more of the bits & pieces I need for this build. Metal gear servos for certain.

Red_Jeepster

All finished with Tail feathers. Now I'm clearing off the bench for the start of the wing panels. This is going to take a bit of extra time, as I am NOT building the 2-piece as per the instructions. Instead, I am building the panels with flat wing root to butt-up against the fuse. The Fuse is to be modified to include the shape of the wing. This solves 2 problems. 1. A Good SOLID mounting of the wing as the wingtube will pass thru the fuse, and not just 2 screws holding it on. 2. it gives me a way to access the interior of the fuse while the wings are mounted. I can load the cargo bay with all those ping-pong balls or skydivers or candy from the top. An access hatch allows this all.

WILDCRASHWILLY

Sounds great Red,

Be sure and take pictures. I like to see how mods are done.

dabrown

Test flew my SD with the G-38 yesterday. Second flight ended as a dead stick. The Tygon fuel line melted against the muffler! I didn't expect that to happen, consequently I didn't take care to route the lines properly.

It was nose heavy and my first takeoff attempt ended up with the prop digging into the runway. Got it airborne and it flew OK, but definitely not great. The CG needs to move back alot so I'll be moving the battery and adding ballast to the tail. The other thing is it needs more prop. The G38 with an 18-8 revs up, but the airplane doesn't accelerate. Needs a 20 inch prop and that will create ground clearance problems...old story with this airplane and the big gassers. I ordered an 18-10 so may give that a try.

Dave