Hi guys...

Thought I'd start this thread to describe the process of turning my Trex 450SE (Gen1) into an Apache. This is at my wife's suggestion, who thought it would be "cool". Considering the distain most of our wives/husbands/better halves hold this addiction... I mean hobby in, I though I'd better leap on it!!!

Many thanks to Darthdk, who has provided the opportunity to do this to my poor 'Rex. I recieved the kit yesterday. Holy styrene, Batman!!! Many, many parts. I will post pics when I get my camera back from the dead. Overall, the quality is top notch, lots of scale details, but the styrene has been drawn very thin for light weight. From my own vacum forming experiences, this is the mark of a master!

I am awaiting an elevated tail kit from HubDave, which will allow a scale placement on the Apache.

Hopefully I won't have to modify my 'Rex too much, but already I can see the following issues:

• Tail boom length - much less than the scale kit
• Tail Rotor height - based on picks, I think I'm going to have to modify Dave's tail
• See above... Tail belt length....
• Securing mechanics and body together.
• Sourcing landing gear - main and tail

Hey... Ed does describe it as an 'expert' level kit. I don't think I'm one of those, but I don't see any insurmountable problems... (Of course, if he wants to weight in with his opinion on the build, that would be alright, too...)

ed

I told you it was alot of parts. Just take your time trim carefully and you'll be alright. I like to see it even as you progress. If you have any probs or need something , Im an email away.
As a note you may want to go with a seperate tailmotor for tail control. Brushless 300 size motor sounds about right.

Oh, don't worry... We will be talking... Anyway, here are the pics I promised. I would like to go with a belt driven tail - I don't like seperate tail motors (personal preference, not the starting point for a pro/con debate), and I like the challenge.

Here are the pics I promised.

ed.

I wanna see this thing do 3d lol

lets see someone 3d this one.....http://www.techmodelproducts.com/twinn_rexx.htm

I'm a little bit green with envy here,but glad to see someone doing this,i had a few sleepless nights and some email talk with darth pondering over doing this,in the end i decided not to,the main reason being how painfull it would be to stuff a beautifull perfect scale apache into the ground,as i tend to do now and again still ,its painfull enough when its just a normal trex,so maybe next year for me,but for sure some day.Please keep the pics and progress coming.

Sorry for going off subject here, Darth - Any chance of getting one of those apache fuselages for a rex 600?
ACE

Hey this should be a good thread!

Originally Posted by aces_high

Any chance of getting one of those apache fuselages for a rex 600?

Darth - no responses on this one until I've built the 450 version. I was at the LHS the other day... The bad man was teasing me with a 600. Price is about the same as when I first got an SE.... He is a very, very bad man.

The prototype Apache can do "loops" and high alpha stall turns, why not the model? Oh right, my skill. Or lack thereof.

Having thought about this all night (not really... ) I think I will attaching the hull to the mechanics using a CF doubler plate that attaches the existing landing gear screw points. This will also carry scale gear - possibly Robarts Robostruts. I would like to have the compression action as the ship settles to the ground. I'll post a drawing for constructive criticism a bit later on. Does anyone know of a good source for CF plates/sheets? I don't think my LHS has any...

I have to get some accurate measurements of the tailboom length and rise to figure out what I'll need to make in terms of an elevated system. The TR is on the right in stock form, but I don't forsee a problem fliping it to the left. Once again, does anyone know of a source for long(!) tailrotor belts? I am concerned and aware of the potential for increased drag with longer length and more "bends".

Any thoughts on switching to asymetrical rotor blades? Flight duration is more of a concern here than 3D ability. I'm thinking of a Neu 1105 in combination with Like90 blades. Hmmm... more to think about.

Got to subscribe to this thread ,,,looks like a good one .... good luck with the mods and keep us posted with plenty of pix along the way .


I am going to have to change my signature to .... to many projects and not enough time
Larry

A Lynx Mk9 or Merlin would be very good aswell.

Sorry again Ed

Ed - have you considered using a shaft driven tail instead of the belt drive? it would probably require less work and parts would be easier to find or build. Also you wouldn't need to worry about incorperating a 'belt adjustment system' of some sort, which could be tricky to create without loosing the scale apperence.

ACE

Ive thought about using a shaft system using boat hardware such as turnbuckels and u joints. I dont see why it wouldnt work.

Yes, I have thought about a shaft system. Very hard, in fact. I started designing one. The biggest problem is getting bevels to take power off the main shaft. They need to be very small... I like the idea of model boat hardware - that's how I came into the hobby. I sorta gave up when I realized that I would probably have to machine parts to fit into the back end of 'Rexy. However.... I think I maybe rexamining the issue. Based on cursory measurements, I think shaft maybe the only way to go. I suspect any belt that long is going to run into significant drag and harmonic vibration issues...

ed.

Okay, I am officially re-examining the issue. I will need to find 90 degree, 1:1 mitre gears for 3mm shaft, then I can get power off the tail rotor drive system into a shaft, then...

I will need to make my own tail rotor transmission. !

Does anyone know of any heli's in the T-Rex's size class that use a shaft driven tail? That might be easier....

More pics: (Darth, I didn't hack up the body, just a very rough fit (held together with medical tape....) )

ed

...

The shogun has one version that is shaft drive and uses a bevel gear system on the tail box and I think it uses a gear to pull the tail drive off the the drive end


here is one location to take a look

shogun off the big main gear.

As far as mini beveled gears go try this place SDP/SI

Good luck and keep us posted