Power Kite Forum

Mistral - A new composite buggy is born

Sand-Yeti - 13-9-2009 at 12:12 AM

The mistral is a cold, dry & violent, northerly wind that blows through Northern Europe.

Giorgio introduced his Mistral in a freaky wind wind last Friday reminiscent of the European Mistral despite being in an Asian Arabian desert.

With the launch ceremony out of the way which, meant imbibing Italian Champagne and the winds settling down a bit, I got to check out how this new animal performed.


The Mistral weighs in at 31 kgs. Considering the wheel & BF's weigh 21 kgs, this is a remarkable weight reduction over anything else I have ever run through the dunes.



Colour scheme was a bit Italianish but Giorgio assures me that it is more in keeping with the UAE colours, which are red, white black & green. You have to admit that it does look very smart. It has a superb, highly polished paint job that rivals the paintwork on a Mercedes.
The seat is from Buggybags, UK & has all the trademarks of BB's high quality work.

The rear axle is 1.6m long held to the side rails with a couple of stainless steel bolts that are easy to remove for fast disassembly. The BF's are held on by 20 mm stainless stub axles stuck into the rear axle.



The rake angle looks to be about 60º, which is much too shallow for my liking.
I prefer a rake angle of around 70º. The buggy is a bit too low as well for running the dunes as I was later to find out.
However, the white swan neck is about the closest thing I have ever seen to a real swan's neck. It is a beautiful piece of work.



The front fork is a work of art and looks superb


Launching my 6.5m Blade IV sat in the Mistral had me rapidly accerating forward.
Running over the sabkah, I noticed a slight twisting of the down tube. I made a mental note that this should be stiffer. A few gentle turns just to get the feel of it & then I started throwing it about like I would my clanking UDB or DB-I that are around 50 kgs. The Mistral would spin so fast that I was going in reverse before I new what had happened.

The buggy was uncanningly stable but not stable enough to stop the empty champers bottle from falling off the rear axle.


Into the dunes and what a delight to race up steep dunes in fairly poor wind. It was effortless. This is where this buggy really comes into its own. Winding over & around the dunes was sheer magic. However, the low nature of the buggy had me ploughing the tops off of the sharp dune ridges so that very soon I had a seat full of sand.



Sadly, the wind got tired & my Mistral buggying afternoon was over. I can't wait to give it a real longer test on a decent wind day.

I just bought a new house and offered Giorgio to swap it for his Mistral but the Mrs. was behind me & I was slapped harshly behind the ear.

Giorgio has already chopped the swan neck. He is increasing the rake angle & giving the Mistral a bit more ground clearance plus improved down tube rigidity.

I thought the Shamal was a superb buggy but the Mistral is very elegant and a new generation of composite buggy has been born.

Congrats to Giorgio on building a fantastic buggy.

furbowski - 13-9-2009 at 03:37 AM

wow... 10 kg minus the rolling gear sounds seriously cutting edge... I can see how that would fly up hill! Sound like a wonderful 3D wind playland you live in, I've long admired your flying area...

Yes the colors are smart but a bit odd... I can't help but wonder what it would look like with all the green bits red and all the while bit black...

Will lifting up the seat require a new swan neck? Or can it be done otherwise?

thanks for sharing...

krumly - 13-9-2009 at 07:36 AM

Pretty cool.

Might I ask what the construction method is? Is it a proto wet layup layup over foam cores, pre-preg into female moulds, or somewhere in between?

Any provisions for adjusting for leg length in the swan neck? Are caster, camber all fixed?

What's your take on damping and shock absorption of the composite vs steel? Maybe running it on hardpack or in fields with ruts and rocks would be a better test of that?

krumly

Sand-Yeti - 13-9-2009 at 08:23 AM

Quote:
Originally posted by furbowski

Will lifting up the seat require a new swan neck? Or can it be done otherwise?


As I mentioned in my post furbowski, Giorgio has already cut the downtube as part of the modification to change the rake angle and lift the buggy as well as stiffen the modified down tube. The swan neck isn't actually a tube but have gotten used to saying down tube because of the steel buggies that I have built.
The swan neck by the way is an integral part of the siderails. i.e. it is not bolted to the siderails.

Sand-Yeti - 13-9-2009 at 08:37 AM

Quote:
Originally posted by krumly
Pretty cool.

Might I ask what the construction method is? Is it a proto wet layup layup over foam cores, pre-preg into female moulds, or somewhere in between?

Any provisions for adjusting for leg length in the swan neck? Are caster, camber all fixed?

What's your take on damping and shock absorption of the composite vs steel? Maybe running it on hardpack or in fields with ruts and rocks would be a better test of that?

krumly


Giorgio built the buggy and is a specialist using such materials that are used in Class I Power boats. That's what he does for a living.

It is customised for his body size. He's a bit taller than me (an inch or two max.) so he doesn't need to make it adjustable.

I will ask him to respond directly with construction details.

furbowski - 13-9-2009 at 08:54 AM

:lol:

missed that line... the pictures were too sweet!

Sand-Yeti - 13-9-2009 at 10:05 AM

Quote:
Originally posted by furbowski
:lol:

missed that line... the pictures were too sweet!


No problem but believe you me when I tell you that the buggying in the Mistral was sweeter.
Cheers S-Y

furbowski - 13-9-2009 at 10:14 AM

Quote:
Originally posted by Sand-Yeti

No problem but believe you me when I tell you that the buggying in the Mistral was sweeter.
Cheers S-Y


I believe it, climbing up those dunes and over the crests with a superlight buggy and a lifty kite must be magic!

:o

giorgio - 13-9-2009 at 10:34 AM

The whole buggy is wet lay up carbon epoxy vacuum bagged over foam core. Unfortunately the swan neck requires surgery to modify rake angle and ride height. Ewasy to do, just a pain though...having done it before on the Shamal it's not a big deal. The one reason why the frame and axle are a lot smaller in section than the Shamal is that i wanted some form of shock absorbtion without having to go to all the trouble of fitting proper dampers. Our terrain can get pretty nasty when you are trucking along in the flat at 60 + km/h and suddently you cross the tracks of a 4WD ..the ride is definetly softer than the Shamal and i will probably experiment with an even softr axle in the future. The only steel buggy i have tried before was my PL comp and occasionaly Sand Yeti's Death Buggy, which is definetly a different ride than the Mistral, not so much stiffer but feels heavy...

jantie - 24-9-2009 at 12:04 PM

i wonder how it will hold in strong winds..
there is the probability that in a upwind-turn everything goes up. :tumble:

but it looks great!!

popeyethewelder - 26-9-2009 at 12:00 AM

Quote:
Originally posted by jantie
i wonder how it will hold in strong winds..
there is the probability that in a upwind-turn everything goes up. :tumble:

but it looks great!!


You must remember Jantie, this beauty is built for the desert and the huge dunes....its a whole different ball game from the flat beaches we use where weight is a big factor...

The Mistral, I know will be THE BUGGY to have in the desert, SY made the comment once that riding Giorgio's previous buggy (The Shamal)was like riding on air, and that was a very accurate description, I had about 20 minutes in the buggy, and after being used to the heavier buggies we all use, it felt like I was just gliding across the sabka in a buggy with no wheels....just floating, the difference it felt in weight was amazing, I never went into the dunes with it....but think about it, a kite dragging a 50+kg buggy up a powder soft dune twice the height of a house......or a kite dragging a 10kg buggy.....theres no argument, plus it has all the other dimensions of a big buggy, so has the stability and strength also.....Desert/dunes = Mistral...the perfect combination

rocfighter - 15-3-2011 at 05:47 AM

Weifeng was reported.