Shwagulous

I'm not sure if this should be in this forum or the ARF but......

I purchased a Kadet ARF kit last weekend. It's going together really easily, but I do have one concern, and I'm hoping to get some good advice from here.

The wing for the ARF bolts on. That threw me for loop from the get go. I thought the Kadet wing used rubber bands to attach it to the fuse. Anyway, the wing bolts on with two nylon bolts in the back, but it only had a cheesy 1/4 inch thick by 1/2 inch long square dowel thingy in the front (Do you like the technical term "thingy"?). I'm a little worried that this will be a very bad situation waiting to happen. I guess what I'm wondering is, has anyone on here built the LT-40 ARF with this type of wing setup, and had the plane live to tell about it? I have other planes with this style of wing mounting (World models 40 sized P-51, and a PT-19), but the both have a fairly beefy dowel in front.

Thoughts? Opinions?

- Paul

bubbagates

My Feedback: (32)

Paul,

I had that exact same setup and it holds up well. Mine cartwheeled and the wing stayed put. It wasn't a bad cartwheel but the wing tips took a good beating. Once you bolt it on and pick it up y the wing you'll feel how strong it is

Shwagulous

Bubbagates,

Thanks for that info. I'm just a little nervous because I'm sure I'll fly this plane a little harder than it's intended use, and I just don't want to be worried about the wing flying off during a loop, or a spin, etc...

- Paul

M. Michael Meyer

I have a LT-40 ARF and it works great. No problems. I just had the first repairs on the plane. It involved the flare on my landing. I did a perfect flare - 6" after I touched down.Broke out a portion of the firewall and drove the front landing gear support back about 1-1/2" into the fuselage. Repairs were fairly simple and it was back in the air the next Saturday.[sm=sunsmiley.gif]

bruce88123

This is a fairly common attachment method used by many ARF's. It'll be fine.

Lowlevlflyer

My Feedback: (3)

Let me assure you, the wing attach setup is MUCH stronger than it looks. My LT40 is the ARF with the same bolt on wing. I've moved on from the trainer, but I still fly it quite a bit. I fly the living crap out of mine when I fly it, and have never had a problem with the wing. I cant say the same about the one I had before that, which was an earlier version LT40 ARF with the RUBBER BAND wing. That wing came off when all the bands broke in some heavy winds. You wont have any problem with the wing on yours, so dont worry. I've got the throws maxed out on mine, and put it through every maneuver I can get it to do. It's got over 100 flights on it, and it's still going strong. Just put her together and go do your thing, she'll take it, trust me.

Shwagulous

Michael,

Sorry to hear about the uh.... delayed flair It's good to hear that you're back in the air though. I can't wait to get mine in the air and do my first 20 million touch and goes.

- Paul

Rcpilot

My Feedback: (78)

I have the LT-40 ARF with the same bolt on wing.

Power is a Tower Hobbies .75 engine.

I scratch built barndoor ailerons and flaps for it. Flaps are controlled by a single servo in the center of the wing and a rod that works the torque rods that were intended for the strip ailerons.

Ailerons are controlled by servos out in the wing bays. 2 aileron servos.

It's a taildragger with a JR 9011 servo mounted in the tail to control the tailwheel. That servo is mixed into the rudder and programmed for the throw I want on the tailwheel.

Throttle is Hitec 425. Flaps, elevator, ailerons, rudder are Hitec 475HB. 7 servos all together. Hitec 8ch Supreme RX. 1650mah 6V MH battery.

Tank is 14oz.

I fly the SNOT outta this plane. I snap it, do rolling circles, hover it--anything you can imagine. I fly it HARD. No mercy!!

Wing bolts are holding up just fine after about 200 flights.

tsands

My Feedback: (3)

This is the best practice you could ever do, GREAT PLAN you'll have a blast

NM2K

My Feedback: (14)

Just keep in mind that any aircraft, model, full scale, manned, unmanned, etc., can be pushed past its point to endure the G-forces one places upon it.

If you know that you are going to fly it hard, take a little time to find the weak spots and perform the mods before your first flight.

The strength of high quality 1/4x20 nylon bolts is not usually a problem. I know pattern flyers that used #10 nylon bolts for their hot 10cc powered models with nary a problem. I would look at the places where the leading edge tang is captured and strengthen that up a bit (soaking in CA?). Also, the places where the nylon bolts thread is an excellent place to ensure strength. Triangle stock and strengthening the threads with CA (unless the threads are metal T-nuts!!) is also a good move.

To me, one of the most enjoyable things to do in R/C airplane flying is to exploit every aerodynamic aspect of a good trainer. Believe me, it can take years to do everything possible with an almost completely stock trainer.

Models that I enjoy in this fashion are:

Goldberg J-3 Cub (kit and ARF)
Telemasters all sizes (kits and ARF)
Sig Kadets all sizes (kits and ARF)
Das Ugly Stiks, Big Stik, etc. all sizes (kits and ARF)

This is just to name a few.


Ed Cregger

SeamusG

The Kadet Senior kit has no ailerons and uses rubber bands to hold the wing on. Many builders (like me) have add ailerons and convert it to bolt down wing.
The Kadet Senior ARF has ailerons and uses bolt down wings. I lost mine when the wings folded - the nylon bolts were still attached to the fuse mounting points but the fuse mounting former was torn out of the fuse. Nylon bolts held nicely.
The LT-40 kit has ailerons (single servo) and uses rubber bands. I am in the process of converting my LT from rubber bands to a bolt down approach, dual aileron servos and taildragger (there's a thread in the kit building forum).
The LT-40 ARF has ailerons (single servo) and uses bolt down wings. No personal experience with this plane.

Nuthin' like personal experience - sometimes I just can't remember what my experiences were ...

jpjamie

I've flown a much customized ARF version of the SIG LT-40 for about 4 years now. The fuselage is fiberglassed, I use Dubro landing gear, Fults forked nose gear and spoilers top center of each wing panel. Spoilers are very effective on windy days making finals sinkably predictable. This bird has a huge flat bottom wing and floats too much on windy days. With full spoilers you can use 70% throttle right up to a few feet off the ground then cut throttle for a smooth as silk landing. Loads of fun with high finals on calm days, comes down fast for loads of speed on landing. Also beefed up the rear firewall support for the nose gear and power the thing with a O.S. .61 two stroker. At first I thought the "tooth" in the front of the wing was a bit of a issue, but my version of this ARF is even heavier than the original and so far no problems. I would like a foam wing. As mentioned above, do regular pre-flight checks and fly the SNOT out of this aircraft!

JohnBuckner

My Feedback: (1)

Paul your airplane is fine and you will be fine don,t get carried away making endless mods, just fly it.

If it makes you comfortable just drip a little thin CA on the wing tang suggested by NM2K and go flying.

John

exeter_acres

My Feedback: (2)

the LT 40 kit used the rubber band...

the LT-40 Arf uses the bolts and has for years.....

go fly and have fun.,

Augie11

I had one for several years and used it as a trainer for new pilots. As if that wasn't enough I had her on floats for 3 years with at least 200 flites off the water. No problems with the wing 'thingy'. Finally sucumbed to a mid-air while we were trying to fly 3 of them, with floats, in formation. There's a reason there are no 65 year old pilots in the Blue Angels : ) !!!!!!

captjckirk

LT-40, either wing system works fine. I've built 4 from kits, and currently have an ARF. Just a suggestion on power, the LT-40 needs a little more boost up front than the standard 40 size engine. I have a Magnum 46 XL in my ARF, it does a great job of doing what ever I want it to do. Also with set of Planefun floats there is plenty of power for that too. Have fun with a great fun plane.

SeamusG

Sorry for the "off topic" post

Hey capt'n kirk - My kit LT-40 was powered by an Evo 52 NX. At anything above 1/4 - 1/3 throttle it pointed its nose up at maybe 30 - 45 degrees and proceed to exceed every "high altitude" limitation of our field (just kiddin'). Not a whole lot of fun when trying to demonstrate throttle management while doing basic training maneuvers. I've downsized to an OS 46 FX (just breakin' it in) hoping to reduce the affect.

Suggestions to better manage the "snobby" nose up attitude? Yes, I understand that the throttle is "THE" control to change altitude with a flat wing trainer. I would just like to have "straight-n-level" at something over 1/2 throttle.

TIA

carrellh

Put a popsicle stick (possibly two) under the trailing edge of the wing.

SeamusG

Em - after thinkin' "what the heck" (original post go censored) - it dawned on me that you're talking about changing the wing's incidence by kicking the TE up. I'll give it a go!

thx

carrellh

Right! It worked on a Thunder Tiger trainer my brother had.

captjckirk

Popcicle sticks, should work fine, but I woild suggest a piece of 1/4 inch balsa. Those who have built the LT-40, or the Kadet Senior have found that Sig built a lot of positive incedence in. I've also trimmed in some down elevator, I think you will find this will help.

SeamusG

hehe - I dialed so much down that there was no "down" left! Me thinks that SIG's approach to the wing incidence is how they size it as a .40 plane. Same thing with the Kadet Senior - an 80" wingspan ".40" [:'(] - my 1st plane (may it RIP).

w8ye

My Feedback: (16)

I glued two pieces of 1/4" maple ply back there across the dihefral

Then I sanded them flat across to match the plate in the fuselage

SeamusG

And how did you then seal the fuse & wing bottom? I never done anything but a "finishing resin micro balloon" putty.

w8ye

My Feedback: (16)

The gap was not 1/4" but more like 1/8" just at the very back and the back was sealed by the spacer. The 1/4" plywood piece rested on the the support at the back of the wing opening in the fuselage and it is recessed.

So there was only a small gap partially along the sides. I didn't seal it.