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Things I found in storage - Trainer Foam conversion and Build

#1
Many many moons ago (1984 to be exact) my father bought an RC plane to build later on whilst traipsing through Europe. He moved on to full scale aircraft and the RC plane never got built. It was one of those things that as a child I was always dreaming about, expecially how much potential fun there was and it was constantly fuelled by seeing this box with sleek graphics all over it sitting on the top of the book case. Roll on 28 years and I've finally managed to find the time and spare cash to get into the hobby.

I've been hugely influenced by all the really cool builds using Foam Board as a medium and have had a go with pretty good success but they've all been 'bull in a china shop' builds all done by following concepts than chucking them together. My desire to see this wondrous thing sitting on the book case was so deeply ingrained that I reminded my dad about it and low and behold he said - "Yeah still got that, it's in storage downstairs!".

You can imagine my haste in barrelling downstairs to see if I could find it. I did find it but with an added bonus! He had two planes tucked away!

Here they are!
How cool are the transmitters!


Check it out - it still has a really old school inrunner and the battery pack




She's a fairly substantial trainer - 38 inches long and 49 inches wingspan


So I figured before ploughing into these beauties with my utter lack of experience I should take the time to learn the techniques involved in Balsa wood and film construction and do them justice. But they have given me a base with which to try building a similar aircraft from the plans out of foam. So with the little experience I have I've gotten started. My father and I are going to build the wing from hotwired blue foam and I've decided to not bother with the cockpit on the plans. We've changed the airfoil to a semi-symmetrical profile and so as not to run the risk of damaging the kits landing gear we're just going to make a skid and belly land it. Either that or I'll make some gear and make it a tail dragger.



We hope to get the wings hot wired out this weekend and there is a pretty hefty order on the way from HK with the rest of the bits that should get this up and going. I'm anticipating it looking a bit like a full fuse Slo Stick.
 
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pgerts

Old age member
Mentor
#4
You have some fine pieces there.
I would recommend you to build it as the kit says BUT - with modern electric motor and battery.
You might want to be careful and keep the tail as light as possible not to need to much lead in the nose.
One alternative - but not beautiful is to mount the new motor in front of the front "firewall" instead of behind.

Keep the landing gear as suggested if you do not want to alter to much - it is designed to be fine as is.
 
#5
Oh yeah - when I actually build the Kit I will follow the instructions exactly but for now I'm just borrowing the concept to make a good flying model. It's all fun :D
 
#6
It begins!

This weekend was pretty productive. As I wanted to do I managed to get the wing cores hot wired out but in a fit of productivity I ended up going a bit further.

First the wing cores taken care of. We're gunning for a 1400mm span wing but being conservative we cut across the foam which is 600mm wide. We've cut 3 sections so that I can cut the third and form some wing tip extensions from it.

This is my father by the way - turns out hot wiring is much easier with two people!








Having got that done and now having to wait for a bunch of stuff from HK, I got a little carried away and got to thinking. I wanted to make a revisit on the motor glider theme after a moderate success with my Ugly Franken Motor Glider.

http://forum.flitetest.com/showthre...KFM2-franken-motor-glider-(57-quot-or-1450mm)

I tend to spend a bit of time looking at aircraft and picking and choosing what design aspects appeal to me and after a bit of a browse and sketch session I came up with this.

 
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#7
I got to hunting for a good airfoil to use and settled on the Clarke Y, printed out some end plates and set to cutting them out!

Here they are next to the Trainer and original Franken Glider wing


The next trick was the fuselage. I decided to go with a carved foam core - first time I've tried this so bear with me.

Rough Cut


Profile sketch ready for band sawing. The fus is in 2 parts hot glued together.


Started forming


Sanding the sucker down - very carefully


Almost finished - still figuring out the nose - I'm thinking that a blended spinner with side vents for cooling would suit the design


With the wing


Mocked up with the tail from the trainer


Now it's a waiting game for the stuff that I've ordered to arrive. Next weekend will hopefully be the first approach to glassing the wings. I'm hoping to be able to utilise the Vacuum Bagging technique.
 
#9
Thanks :D
The Hanger is one of my Fathers - it's a pretty cool place to hang out and get inspiration for designs.

I'm going for a bit of a scale look rather than the classic RC glider style. I'm taking my design queues from these two planes:

Phoenix Motor Glider


Nemesis NXT Reno Racer


In fairness it's a bit more the Phoenix than the Nemesis but I want to get that really nice sleek profile especially on the nose as I think the Phoenix one is a little soft. Still - we'll see where it goes :D
 

colorex

Rotor Riot!
Mentor
#10
But is your glider going to be high wing? or low wing as the pictures?

It would be great to check that hangar out. Maybe you can show it off to flitetest for the full-scale aviation project they're working on.
 
#11
No, I'm going to go high wing like my drawing with nice blended landing gear. It's a tail dragger with a recessed tail wheel. Haha - dunno about showing off the hanger - the a few of the planes in there are owned by other people and I'm not too sure how keen they'd be to have people nosing around them. As for my dads planes, I'm sure I can get a few photos up of what's going on with them. I suspect that Australia is a little far off the map for the FT guys anyway! I need to have a look into the full scale project though - that peaks my curiosity!
 

colorex

Rotor Riot!
Mentor
#12
No, I'm going to go high wing like my drawing with nice blended landing gear. It's a tail dragger with a recessed tail wheel. Haha - dunno about showing off the hanger - the a few of the planes in there are owned by other people and I'm not too sure how keen they'd be to have people nosing around them. As for my dads planes, I'm sure I can get a few photos up of what's going on with them. I suspect that Australia is a little far off the map for the FT guys anyway! I need to have a look into the full scale project though - that peaks my curiosity!
Oh, Australia! That's really far away. It would be cool to see some info on real planes!
 
#14
We have a spinner! Not exactly what I was going for but the best that the shop had going. I really want to put a 3 bladed prop on it but 2 will do for now. I've got some slowfly props on order that should fit - the 8x7 is probably a bit much for a motor glider!

 
#15
Unfortunately I haven't had the chance to get back into working on these models - it's weekend only stuff and then only when I can get out to the hangers. I decided to work up a render of what I hope to get the plane looking like. Most of my bits arrived from HK but now I need to get the bits and pieces for glassing and vacuum bagging as well as building an oven for curing.

 

colorex

Rotor Riot!
Mentor
#20
Heh - I know what you mean - I'm not so awesome at it either. It's hard to keep geometry clean - I have a huge amount to still learn.
I would do that with top and side views extruded and intersected - then apply a fillet on the edges. Then I'm stuck. I'll have to learn someday.