JimTrainor

Fuse width at F2: 3.5 inches

These fit perfectly IMO:
http://www2.towerhobbies.com/cgi-bin...&I=LXJ924&P=ML

bojangle

Thanks Jim. I guess one could rebend the gear to gain some needed height. One more question...on the GP L4 gear, can you give me the dimension front to back of the large 60 gear? I understand the width across is 3-5/8", I am talking about the other "width" of the mounting area, or would you call that the "mounting depth". Hope I'm explaining this correctly.

The LT-25 with 3 inch wheels has a total height to the fuse, plane sitting level, of almost 6 inches.

I think most of the dural gear was designed back before the popularity of 4 strokes. Excuse the many questions, it will sure help when I can see the plans.

Bob

JimTrainor

The other dimension is 2.5 inches.

4.25 inches high to the axle
14 inch spread.

They pretty much match the gear height and wheeling spacing of the stock wire gear.
I find they look "about right". I have a set of GP 40 size dural gear and they look too small.

bojangle

I ordered one of the L4 today. 2.5 inches seems wider than I had visualized, just have to look at it. I used to use a lot of durals from "Halco", can't seem to find them anymore. They were very narrow, but very sturdy. Seems that everytime I get used to something, it gets discontinued.

Did you get your LT together? Anxious to see some pics if your computer will talk to you lol.

Bob

bojangle

The LT-40 kit arrived this morning. After a thorough check of the parts, I have to say it is by far the best kit I have ever bought. Every piece is of perfect quality, pre-shaped, sawn, die-cut, laser-cut, routed, (as promised) and I would add..milled, beveled, notched and smoothed. I've always had a policy of never buying/building the same kit twice, but I will make an exception and order another one for my collection.

The wing probably needs no mods except to make it a bolt-on and dual servos (in anticipation of a future computer radio). The fuse is 100% plywood which makes a strong and true skeleton, however I am contemplating adding a 1/16" balsa skin over the ply. I have heard that this plane tends to come out tail-heavy, so lengthening the nose may be an option.

For now, the kit must stay on the shelf until the ranch work is caught up. Also I want to spend a lot of time studying the plans and manual to avoid "painting myself into a corner" at some point. Once construction commences, I hope to post notes and pics of significant changes if any.

Bob

Ugo Ferrari

My Feedback: (1)

Hey Bob, Whew, that sure is a lot of replyst to got thru before I got my chance to add my two cents...
Looks like most of my mods were included. Such as flatten the wing, two aileron servos, bolt on wings, and forget the flaps ! That was a bad Idea ! But, did anyone clip one bay off the wing tips to reduce, or eliminate the "Float on By" tendency of this bird ? I also had to add two popcycle sticks under the trailing edge of the wing (As suggested by RC Report's Ed Moorman) to get this thing to come down. That really helped ! Now the landings are under MY control not the planes.

For what it's worth..., My Color Scheme !
Ugo

bojangle

Hi Ugo
Sorry you had to wade through so much to get here As you have noticed, I am sorta long winded lol.

Normally I wouldn't do this much research, but it is my "100th" plane, hope I made the right choice.

My only concern is the all plywood fuse, I'm used to all balsa. Did you have any problems covering the plywood? I'm considering skinning the whole thing with balsa. I like the yellow, one of my favorite colors and it shows up well. Thanks for the tips.

Bob

Ugo Ferrari

My Feedback: (1)

Bob, Don't waste you time ( And Balsa) sheeting the fuse ! The ply covers over very nicely. The fuse is long as you know so, do it in sections,starting from the rear. Don't attempt it in one piece, It's a mess ! LOL !
I think the vertical stab problem was covered...Anyway, I added a couple of two inch "Keys" to the bottom of the vertical and cut matching slots in the horizontal stab to accomodate the keys. Very secure !!

Ugo

mab0852

I love my LT-40. I agree 100% with the above mods. No dihedral, dragger, bolt on wing, dual aileron servos are a must if you plan on doing anything but a lazy pattern or loops. With a computer radio the flaperon option really helps take some of the float out of the landings. For the vertical attachment, I used two small hardwood dowels. I just broke off two pieces of pencil lead and pushed them into the stab. Then you dry fit the vertical and the lead will mark your drill points. Remove the vertical, drill on the pencil marks, insert the dowels and epoxy in place. This has worked very well on mine. An additional in flight benefit of the tail dragger configuration is the ability to move the CG back. When mine was a trike the CG was directly above the center of the wheels which made ground handling interesting. I wanted the CG a little further back so my only option was to convert. I would also recommend the Sullivan tail wheel given that you are using a pasture. I frequently fly from pastures and I prefer free wheel to tiller. Its easier to rig, lighter and easier on the servo given rough terrain. Another point on the terrain, 1/4-20 nylon bolts are a must for the landing gear. Ask me how I know?

Righty

I just have a quick question.

I have an Alpha trainer and i am converting it to a tail drager. I was wondering do you think i will still be able to mauvere it while taxing if i do not connect it to a push rod so it moves freely by itself?

Ugo Ferrari

My Feedback: (1)

If there is any breeze, it will tend to "Weather Vane" and go where ever it pleases. You will never have any ground control until it gets up on the mains, where the rudder takes over.
Take the extra effort and add the tail wheel steering !

Ugo

Righty

but i bought a tail wheel the has to mount to the rudder but i have the alpha which won't alow me to do that

bojangle

A tail wheel assembly that mounts to the rudder will not last long. You should get an assembly that bolts or screws to the bottom of the fuse with a "tiller" arm. Then you can run either pull cables or just a separate light weight push rod hooked directly to the rudder servo.

There are several good assemblies available from Tatone, Sullivan, etc. Go to Tower and enter "tail wheel assemblies" in the search box for a good selection. Everyone has different and unique ways of setting it up, just do it the way that works best for you.
Bob

JimTrainor

bojangle, I post some pictures of my LT-40!

http://www.rcuniverse.com/forum/LT%2...1963113/tm.htm

bojangle

Thanks for posting the pics.

My LT is almost ready to cover, waiting for some hardware from Tower. The plane has been a joy to build, all parts fit perfectly and the wood was excellent quality though a little heavier than I prefer. Total airframe weight is 3 lbs 5 oz. Specs are for 6 lbs max, think this one will be closer to 6-1/2 lbs.

Total conversion to tail dragger. I have an LT-25 on the shelf, borrowed the dural gear. I need as much prop clearance as possible, if the FS48 doesn't work out, I have an FS70 broken in. I'm at 6500 feet, so may need some extra power.

I moved the control point for the rudder to the bottom/side so as to make the tiller connection directly with short rod or springs. Dual aileron servos, have a computer radio on order. Left the dihedral stock, paper tubes in wing to run servo leads to center box.

Added a fairing similar to yours on leading and trailing edge. Bolt on wing, with 3 dowels at leading edge, 1/4-20 bolts into blind nut under beefed up F7.

Decided not to change the turtle deck profile, just added 1/4" triangle stock both sides of fin and front extension.

Interesting the stab had braces but no ribs, fin had ribs but no braces. I used lightweight 1/4" X 5/16" for these instead of the supplied 5/16" square stock which was very hard and heavy.

Windshield also removable for access to a planned 14 oz tank. Nothing special planned for the color scheme, the supplied decals are great and would be a shame not to use them.

My only concern is the weight, I am used to building much lighter than this. Do you have a total weight on your LT ?

Hope to post pictures in a few days.

Bob

JimTrainor

Mine is about 6.5. (That's using a fairly coarse fishing scale.)

It flies fine at that weight - lumbers along slowly just like the few other lt-40's I've tried.

I wasn't too concerned about the weight as I built mine. Each pound only adds 2.5 oz/sqft to the wing loading.

Fuelled, mine will have a wing loading of about 18 oz/sqft ... which is still a low loading.

bojangle

Thanks for the encouragement, and the reminder about the low wing loading. I keep forgetting the LT has more wing area than most 40s. It even exceeds my GP 40 Cub which weighs 7 pounds. (I put a FS70 on the Cub, it hauls).

After this tailwheel conversion, I want to write to some companies such as DuBro, Sig or GP about redesigning their nylon tailwheel brackets. None of the ones available has enough room at the top for a tiller arm, the arm has to go on the bottom and catches on the grass. DuBro is the closest, but had to file a little to clear a Goldberg 1/8" arm.

Bob

doggscube

My Feedback: (1)

If you're trying to get the control arm on the top of the mount, take a look at what I used:

[link=http://www2.towerhobbies.com/cgi-bin/WTI0001P?&I=LXCLK9]GP scale tailwheel assembly[/link]

Here's a pic of it on my LT-40.

NOTE: this plane has only 4 flights on it (yesterday), but it handled well on the grass runway.

-Jeff