timo944

Lesson:Make sure your exhaust is pointed far enuogh away from the elastics holding the wing on. Bad mistake. The wing came off at altitude and the fuselage did a nosedive into a field. The horses were mighty surprised!

Damage is pretty severe - the motor received the brunt of it. Cracked the case, bent the shaft. Nose cone was totally shattered.

So, here is a question:Iwould like to rebuild this plane. It is a PT-40 (not Mk II)that Ibought in about 1992. The wing, stab, and elevator are fine. Ihave a new motor, and the servos and receiver are OK.

Plan is to:
-flatten the wing out some to get a little more sporty
- lock the wng down with bolts instead of elastics
- install a 4-stroke 0.56
- possibly convert to tail dragger (we have pretty tall grass on our runway)

All I need is a fuselage. Here are my options:
- Great Planes sells individual parts for the PT-40 fuse. not sure whether this is for the MK II or not (They have not answered my email yet). Cost about $55.
- Great Planes also sells an ARF fuselage. Do not know the price yet.
- There is also the SIG LT-40 ARFfuse for $30. I am not sure how easy/difficult it woudl be to make this work??

Can anybody comment on the above?Does anybody know how compatible PT-40 MK I and MKII assemblies are?

cfircav8r

My Feedback: (1)

If you have the craftsmanship to flatten the wing you should be able to repair the fuse easily enough. Just straighten it out, throw on some ply doublers, new bulkheads and a firewall. It'll be almost as good as new, just a little heavier.

Scirocco14

Hey Timo!

You forgot to say how long it took the wing to come back to earth!!



Mark

timo944

After looking at a number of other posts about trainers and the likeIdetermined the same thing. Ithink that seeing the speed with which the fuse nose dived into the ground, itlead me to believe that a rebuild is not possible. After some re-thinking Ibelieve it can be done with relative ease. Iplan a trip to the LHS this afternoon for supplies!

timo944

Hah!That was quite something. And totally undamaged. It's like it was nightfall before the eagle finally landed! While walking back to the paddock after picking up the pieces, the other gentleman who had walked out with me (Ican't remember his name) said "Watch out for snakes!" Gulp!

Mark are you going out this weekend?

Scirocco14

Yikes (on the snakes!). Good to know!

If you want a Low-wing fuselage to mess with, I have a Sukhoi fuselage (low-wing) that I'm not using that might be an interesting "bash" for your wing. You can have it if you want to try it and see if it'll work.

Maybe I'll head over to the field on Sunday if the weather is OK. I was there today and had the joint to myself this afternoon. Got lots of practice in with the trainer and finally started to tame the Goldberg Piper Cub. Once it's off the ground, it's a *****cat but takeoffs are nerve-racking!!

bastige56

Good thing I checked this thread out. Thinking about bolting the wings down now. Just started builing this plane last weekend.

Here is the thread I started.

www.rcuniverse.com/forum/m_9997147/tm.htm

timo944

Nice work - it looks great.

I have started working on the bolt down. I will pn the wing up front and bolt it at teh rear. Ihave seen an LT-40 done this way and it looks good. Also check the manuals for the PT-40 MKII on Great Planes website (it's free). There is an option in the MK II for bolt down wings..... unless you already have a MK II??

I'll post some pics here whan Iget the bolt down built.

timo

ozspit

A bit off topic but snakes are a real issue here in Oz when you're out looking for aircraft remains or in my case Al spinners which have vibrated loose. I think I read somewhere that we have 15 of the top 20 most poisonous snakes right here. Most common are Tigers and Browns (both in the top 10) which can be quite aggressive when disturbed.[X(]

Anyway, fixing an ARF trainer fuse is how I started into building. I still have my first plane, a Seagull Boomerang 40. It's probably only 50% ARF now! It's a lot heavier and the LA46 struggles a bit now. Sometimes a repair looks more daunting than it actually is and it is quite satisfying to get an apparently lost cause back into the air.

Good luck.

timo944

OK, so I've been busy: First, I separated the wing and reduced the dihedral. It was about 12 degrees and I changed it to 5 degress (total). I beefed up the front of the wing where it meets the fuse and installed two 5/16" dowels. On the rear I will use screws to hold the wing down.

The I built two new sides, I figured out where to cut up the fuse to save the most original wood. I staggerd the fuse sides and doublers by about an inch to avoid having a single weak point. I made a new former F-2 and made it a bit taller to accept the dowels. I have also modified the shape of the fuse side so I can sweep the front of the plasne up to the wing top. Nothing on the fuse is glued up yet - still trial fitting.

Lastly, since I will be using a 0.56 Saito power plant, I will move the new fire wall back about an inch... maybe less. I'll need to locate the fuel tank further backward of course.

So far so good. Some trial and error. Worst of all there's no power in the garage so I don't have any power tools - this leads to slightly crooked cuts that require sanding etc.

Next step is to assemble the fuse.

flygilmore

A PT .40 was my first plane. It had less dihedral than the sport wing called for, taildragger, larger rudder/elev. and wing bolted on. It was a very nice plane. In fact, I bought a PT .60 a couple months ago to save for my children to build one day. It will also have the very same mods along with wheel pants. These planes can be made to look very, very nice!

Good luck

timo944

Finshed. I'm confident that this will be better than the original. Modes are:
- converted to tail dragger
- Saito 0.56 4-stroke
- larger (12 oz.) fuel tank
- bolt in wing
- reduce diherdral about 60%

Now all I need is a warm day!!!

Scirocco14

Looks good! Tell me when you're going out to the field, I'll join you!

Mark

timo944

That would be great Mark. I'll be out oftown until Thursday, somaybe Friday or Saturday?It's supposed to be 50 degrees so I'll bring my thumb warmers! Will let you know but let me know if you're going up.

prgonzalez

Looks really GOOD!!!

GOOD JOB!!!

timo944

Well, thank you very much, butshe hasn't flown yet!! I'll post again after her re-maiden.

Avaiojet

Timo,

I've been following your thread. You did a great job with that model. Kudos!

PM me and I'll send you some free graphics or lettering for it.

Does the model have a name?

Father Time

Great job on the rebuild! I am guessing that you have probably already done this, but just as a reminder with the mods you have created, do not forget to double check the center of gravity! I have seen to many new or rebuild projects shoe boxed by this simple oversight. Good luck on the test flight!!!

timo944

One step ahead of you - Ihave balanced and also checked the side to side balance. Igot it to balance perfectly by playing with the location of the battery. Thanks for the advice!

So is it you or Old Man Winter sending this cold weather down here???

Scirocco14

Looked great, I'm digging that Saito you put on it. That's a nice engine, I really liked the beautiful idle. Now get that landing gear moved forward and it won't tip over on its nose so easily! Then you can learn what a "ground loop" is just like I did!

See ya!

Mark

Father Time

Heya! Welcome to Alberta - - and the worst ain't over yet! Flying up here in the winter definitely provides it's own challenges!!!! So ya, if your not used to it, I can really feel your enthusiasm to get out and fly. Thinking about moving to Texas with my son just to beat this cold crap!

Favorite quote - - I keep "planting" them; they just don't grow!!!

timo944

Iused to live in Montreal and spent weeks if not months in Edmonton. I love the snow but the cold....BRRRR!!!

timo944

Update:

Finally got a change to fly. On the first attempt, Idiscoverd that the landding gear was too far aft. Every time I powered up I'd get a nosedive. So back home Imoved the LGforward by about 1.5", using the guideline of 20 degress forward from the leading edge of the wing. The results are good., The new motor is very strong and plane flies really well. She also looks great in the air, thanks to some additional graphics from Charles at CFC Graphics. I chose the pink to match my truck (inside joke).

Take-off is a little challenging (ground loops) but some time at the field to practice shoudl fix that.

Many thanks to Charles of CFC (http://www.cfcgraphics.com/wsnE5A6.html), Mark for the flying support, and Adam for dragging my truck out of the mud!

edmoor

My Feedback: (1)

i couldnt get you last pictures to load up dont know why......anyway...looking down on most any model from the top leading edge of the wing......i like to see the full wheel. if i dont see a full wheel....its going to be a tipsy airplane on takeoff.

timo944

Good to know, You can see a full wheel. It's not too ipsy now, but the good news is I can adjust it since the plate in the aircraft is fairly large.

Thanks