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#1 Gary Binnie Mar 16, 2011 09:53 PM

Graupner Mini Nimbus (another really old one!)
 
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Hello folks,

I went after this kit and ended up with an unbuilt Graupner Cirrus as well.:cool: This is the early built-up wing and tail version, circa 1977.

The Mini Nimbus is a very special glider type to me as I owned and flew a full-size one for 20 years.

I have wanted to build one of these for ages and it will be my next project, hope to start building in a month or so.

The kit is fantastic quality, I have one small gripe with it though; the outline is not very scale. The forward fuselage is much thinner than it should be and the tail system rocker mount is a bit of an eyesore but model designers have to make compromises. Won't even mention the lack of trailing edge airbrakes!! Shall not be entering any scale competitions with it so who cares?!

The plan is to build it exactly as designed, the 'Variopop' linear servos might be difficult to get hold of though!

Some photos.

GB

#2 Gary Binnie Mar 17, 2011 06:26 AM

The big one
 
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Forgot to add some photos of the big one!

Mine was the same version as the model with the all-flying tail, known as the Mini Nimbus HS-7 (HS for the designer, Klaus Holighaus). This tail arrangement caused problems with British certification and the authorities insisted that an anti-balance tab was fitted.

It made little difference to the stick forces in reality, it did have some strange pitch stability behaviour but was not dangerous (technically known as phugoid oscillations!!).

The Mini Nimbus B had a conventional tailplane and elevator and the Mini Nimbus C had a carbon wing spar (could carry more water ballast I think).

If any modeller/full-size pilots get the chance to fly one I would highly recommend it, the airbrake/landing flap performance is eye watering if you use all of it!!

Cheers

GB

#3 John Cole Mar 17, 2011 09:31 AM

Gary, this is cool!!!

John

#4 Sailhigh Mar 17, 2011 12:43 PM

Wow, you got a hold of a couple of classic Graupner birds. Though not exactly scale, the mini Nimbus is a real looker in the skies. Did you fly your DG-600 yet?

Sean

#5 yyz Mar 17, 2011 12:48 PM

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Quote:

Originally Posted by John Cole (Post 17707210)
Gary, this is cool!!!

John

Very cool indeed! Nice find on this kit.

Are you going to attempt to recreate the crazy "flaps mit dive brakes" as on your full-sized ship?

Subscribed,

Mike

#6 Gary Binnie Mar 17, 2011 01:40 PM

That's the ones! Could hold them fully open and descend from wave so steeply that the loose ends of my shoulder straps floated up!! They froze up once, only needed a small piece of ice at the front to lock them, just flew about at low level in the warmer air until they unstuck.

Would be nice to replicate them but I'm going to use the designed Graupner blades.

Yes, I flew the DG600 last week, there is some blurb in the thread on it. Very nice.

Hope to make a start on this beastie soon, the building board is clear.

GB

#7 Sutton Bank Mar 17, 2011 04:40 PM

Yikes! Major nostalgia flashback! In the 80's there was one of these on the very top shelf of my local model shop and I used to loiter furtively by it every night on my way home from school, hoping that the owner would take pity and sell it to me for pocket money. It lay there unsold for years until it had an inch of dust on the top. I came back from university to find the shop gone and sadder still the MiniNim.

It should have been mine.

This life has no justice.

#8 Gary Binnie Mar 17, 2011 04:55 PM

How much was it, can you remember?

I saw one in a model shop in Innsbruck, Austria about 1990. I was flying the big one in the mountains. I wanted it quite badly but couldn't afford it. I wasn't building models at the time so couldn't justify it.

I might have some Graupner price lists in old magazines, will have a look.

#9 Gary Binnie Mar 17, 2011 05:41 PM

Found some info from 'Aeromodeller' April 1981.

Ripmax give a price of 105.50 for this one, 149.50 for the larger span, foam wing version and 55.95 for the Cirrus. The Cirrus 75 was listed at 103. There's a photo of Graupner people laying up fuselages, must scan it.

Inflation calculators say the kit I have would cost around 320 today.

#10 Sutton Bank Mar 17, 2011 06:12 PM

Quote:

Originally Posted by Gary Binnie (Post 17710850)
How much was it, can you remember?

Way more than my pocket money. :(

It was 141.50. It's like I'm standing back in that shop again staring up at the top shelf. Seeing your photo of the box has brought it all flooding back!

By the way I'm a big fan of trailing edge brakes. I have a PT Vega too and fitted simple TE brakes as detailed on the plan. They stopped the plane dead, like an anchor had been thrown overboard, and then it just parachuted slowly downwards. I'd like to build another Vega someday, maybe @1/3 scale. Actually I'd like to build lots of things someday, but the Vega is definitely in the top 250. :D

Rog

#11 Gary Binnie Mar 17, 2011 06:22 PM

Sounds like it was the foam wing version.

The PT Vega is quite a lump, I think this is supposed to be about five pounds, it would stop dead and go backwards!

I flew the full-size Sport Vega, that has trailing edge brakes but no flaps, never flew a standard Vega.

Must scan that photo.

#12 Gary Binnie Mar 17, 2011 06:48 PM

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Here's the photo, must be 30 fuselages there.

Worse jobs I suppose!!

I think the glider must be a Cirrus 75, maybe the fuselages are as well. (Thinking about it they must be Mini Nimbus fuselages as that was the only glass one according to the advert)

Sehr interessant.

#13 tuootal Mar 18, 2011 12:44 AM

2 Attachment(s)
Quote:

Originally Posted by yyz (Post 17708802)
Very cool indeed! Nice find on this kit.

Are you going to attempt to recreate the crazy "flaps mit dive brakes" as on your full-sized ship?

Subscribed,

Mike

Agree that the scale working flaps & brakes would be challenging... but there is one way of doing it, see first pic below. It has been shamelessly ripped from old classic Radio Control Soaring by Dave Hughes from circa 1977. I have read this great book almost to shreds... 'my first rc book'..

That (fig. 99) implementation is rather easy. Just do not use it in planes which are fast... Only slow floaters.

Tuomas

#14 Sutton Bank Mar 18, 2011 05:54 AM

I bought that book too in 1981 and still have the tattered copy! I agree it's a simplified way to get both flaps and brakes, but the brake below the wing is very vulnerable on landing. Full-size Salto has this arrangement, with two short sections on each wing I think.

If I had Gary's kit though I'd just build it per plan - it will fly better light I reckon.

Rog

#15 Gary Binnie Mar 18, 2011 06:52 AM

I go to sleep reading that book most nights, the theory section at the back works best! :D

It would be a nice feature to have but my philosophy with these old kits or plans is to build them as they were intended, even keeping features that we know now could be better designed. I know it appears a strange way of doing things to some people.

I'm pretty stubborn about it. If I can make hidden internal improvements (like using carbon pushrods) then I will though. I used Multiplex 'Uni-Lock' wing retainers on the 'Hi-Phase' instead of rubber bands for instance. I do the same when I'm restoring old motorbikes (fit electronic ignition over contact breaker points).

No problem adding thoughts and ideas to the thread though, that's what the forum is for, someone else might like to build one with modifications. That's if you can get hold of a kit, the seller of this one thought it was probably the last unbuilt kit in England.

So, I better not mess it up!!! :eek:

Cheers

Gary


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