Author Topic: 1/4 scale Opel Rak (Read 99192 times)

joe · « **Reply #75 on:** February 23, 2009, 19:47:02 PM »

Here's the Rak movie from YouTube

[youtube]http://www.youtube.com/v/Z8w19WYxC7Q[/youtube]

mat2verre · « **Reply #76 on:** October 24, 2011, 09:44:32 AM »

Hi Fred,

I would like to know if you finally managed to use powder rockets on your Opel Rak, and how you calculated their power regarding the weight and drag of your model... I am looking forward another project quite similar...

A+

Mat

Fred · « **Reply #77 on:** October 25, 2011, 20:39:06 PM »

Howdy Mat'

Nope, only did a test of the pod with 4 rockets, but on static, not in the glider (just in case!) and never went to test in flight! (even if I finally managed to find a system to fire the rockets remotely

)
For the weight ratio etc, no ideas! I go with the noise and smoke, like the real one (that ended up in flame after a 15 seconds flight...)
Sound like a fun project for next April!!

Fred - Crash and burn... Litteraly!

mat2verre · « **Reply #78 on:** October 25, 2011, 22:40:52 PM »

Ok, so maybe you could tell me which rocket you choose to make noise & smoke??? :lol: And where did you find it??? I am really a beginner in this kind of motor/engine...

A+

Mat

Fred · « **Reply #79 on:** October 28, 2011, 19:33:24 PM »

Hey Mat,

Does that mean you have a project that involve flames, noise, smoke, and hopefully a big bang?

mat2verre · « **Reply #80 on:** October 29, 2011, 10:51:55 AM »

You're right, Fred... A model coming from east, very far east... In fact it will be a little bit the same problem as you: build a glider, and then try to motorize it with a rocket motor...

I just hope I won't verify the big bang theory!

So... what was your solution on the Rak???

@+

Mat

Fred · « **Reply #81 on:** October 31, 2011, 18:14:21 PM »

I see!

So what are you preparing??

For the Rak, the solution was so simple!
I used an old ESC for brushed motor!
Job done! You can light the fuses remotely. Basic, cheap, but wayyyy cheaper than the solutions I found on the net! (youcan buy modules that are programmable, to light all the fuses at the same time, or 2 by 2, etc etc, but cost of such module is about 100 euros or so (at the time)...

andrew wallace · « **Reply #82 on:** October 20, 2012, 19:56:47 PM »

hey fred
was reading through this thread and was looking at the lay out of the model
did it take a lot of lead to get it to balance with such a small fuselage and two long aluminium booms and twin rudders, how many servo's do you have on the tail is it one elevator and two rudder ?

rogallo · « **Reply #83 on:** October 20, 2012, 20:26:05 PM »

not a lot of lead and 3 servos

Fred · « **Reply #84 on:** October 20, 2012, 20:49:08 PM »

Yeah, same as Ralph

I can't remember yhe amount of lead I put, but not a lot.
3 servos. 1 for the elevator, and 1 for each rudders

andrew wallace · « **Reply #85 on:** October 20, 2012, 21:34:57 PM »

:shock: that's amazing :shock:
how does the model fly

Fred · « **Reply #86 on:** October 24, 2013, 11:00:00 AM »

Have to bring that one back!
I received earlier, a video from Italy, showing the Opel Rak.. Fitted with rockets

:clap:

[youtube]http://www.youtube.com/v/C297OQCzWPU[/youtube]

Me like it!

Well done to the builder! First example I see fitted with them :clap:

andrew wallace · « **Reply #87 on:** December 04, 2014, 08:58:58 AM »

The Opel Rak and island models get a wee mention on scalesoaring.co.uk website

:clap:

Fred · « **Reply #88 on:** December 04, 2014, 20:14:31 PM »

Thanks Andrew.
Ka3 in a US mag also this month someone told me.

News:

Author Topic: 1/4 scale Opel Rak (Read 99192 times)