Blizzard from Corvidae.net
 

I've chosen the Blizzard .15 as a new project because I'd had a hot MVVS .15 GFR around, waiting for a model as this. I was looking for something quick and with a sleek fiberglass fuse. Now it's really gotten time to begin with building because I had it laying around for over a year. I promised to make a nice building report, and here it is I believe. ;)

The package arrives
http://www.rc-cropduster.com/users/j...lizzard_01.jpg

http://www.rc-cropduster.com/users/j...lizzard_02.jpg

http://www.rc-cropduster.com/users/j...lizzard_03.jpg

All the components on display. Included is the CNC-pack. Very nice.
http://www.rc-cropduster.com/users/j...lizzard_04.jpg

The MVVS .15 GFR with venturi. M+R engine was also an option, especially as you've seen the price. A .15 M+R engine does cost €90,- (about $100,-) in Germany. The M+R is a modified .15 Rossi Fire, which is very hot! But the MVVS was lying around, so there it is. ;) Note the outstanding quality, great value for money. I also like the blue anodized material.
http://www.rc-cropduster.com/users/j...lizzard_05.jpg


The leading edge and wingtips glued to the wing with D3 glue (for wood, also works well with styropor/foam)
http://www.rc-cropduster.com/users/j...lizzard_06.jpg

http://www.rc-cropduster.com/users/j...lizzard_07.jpg


The wingtips are also attached.
http://www.rc-cropduster.com/users/j...lizzard_08.jpg

http://www.rc-cropduster.com/users/j...lizzard_09.jpg

http://www.rc-cropduster.com/users/j...lizzard_10.jpg

http://www.rc-cropduster.com/users/j...lizzard_11.jpg


Sanding the wings with a 3° angle for joining together.
http://www.rc-cropduster.com/users/j...lizzard_12.jpg

12mm spacing under each wingtip.
http://www.rc-cropduster.com/users/j...lizzard_13.jpg

http://www.rc-cropduster.com/users/j...lizzard_14.jpg

Now waiting until the glue is cured.
http://www.rc-cropduster.com/users/j...lizzard_15.jpg


3x Hitec HS-85MG for the Blizzard.
http://www.rc-cropduster.com/users/j...lizzard_16.jpg

Made a small gap for the servo cables. There's a slot prepared in the foam to make it very easy.
http://www.rc-cropduster.com/users/j...lizzard_17.jpg

I did cut a gap for the servos. Mounting brackets sawed off to reduce the mounting space.
http://www.rc-cropduster.com/users/j...lizzard_18.jpg

Both gaps are finished.
http://www.rc-cropduster.com/users/j...lizzard_19.jpg

Cut a slot to fit the wing spar.
http://www.rc-cropduster.com/users/j...lizzard_20.jpg

Removing styropor / foam.
http://www.rc-cropduster.com/users/j...lizzard_21.jpg

Glued the wing spar into place.
http://www.rc-cropduster.com/users/j...lizzard_22.jpg

Detail photo.
http://www.rc-cropduster.com/users/j...lizzard_23.jpg

Cut out the ailerons.
http://www.rc-cropduster.com/users/j...lizzard_24.jpg

Peace of heavy glass for reinforcement.
http://www.rc-cropduster.com/users/j...lizzard_25.jpg

Entirely covered the wing with 25 gram glass. Waiting for the G4 to set in and dry.
http://www.rc-cropduster.com/users/j...lizzard_26.jpg

Removing unnecessary glass with a peace of sanding paper.
http://www.rc-cropduster.com/users/j...lizzard_27.jpg

Finish all the edges to give a smooth result.
http://www.rc-cropduster.com/users/j...lizzard_28.jpg

Reinforcing the upper side of the wing.
http://www.rc-cropduster.com/users/j...lizzard_29.jpg

Wing reinforcement together with a peace of plywood for the wing-bolt.
http://www.rc-cropduster.com/users/j...lizzard_30.jpg

Smooth!
http://www.rc-cropduster.com/users/j...lizzard_31.jpg

http://www.rc-cropduster.com/users/j...lizzard_32.jpg

Sanded the stabilizer in shape and covered with glass.
http://www.rc-cropduster.com/users/j...lizzard_33.jpg

http://www.rc-cropduster.com/users/j...lizzard_34.jpg

http://www.rc-cropduster.com/users/j...lizzard_35.jpg

http://www.rc-cropduster.com/users/j...lizzard_36.jpg

http://www.rc-cropduster.com/users/j...lizzard_37.jpg

Measured the place for the hole and drilled.
http://www.rc-cropduster.com/users/j...lizzard_38.jpg

5mm carbon wing dowel glued with epoxy.
http://www.rc-cropduster.com/users/j...lizzard_39.jpg

Plate to accommodate the blind nut.
http://www.rc-cropduster.com/users/j...lizzard_40.jpg

http://www.rc-cropduster.com/users/j...lizzard_41.jpg

http://www.rc-cropduster.com/users/j...lizzard_42.jpg

http://www.rc-cropduster.com/users/j...lizzard_43.jpg

Used a pipe wrench to force the blind nut into the plywood.
http://www.rc-cropduster.com/users/j...lizzard_44.jpg

Peace of scrap ply to ensure it isn't damaging the fuse.
http://www.rc-cropduster.com/users/j...lizzard_45.jpg

Complete view of the project.
http://www.rc-cropduster.com/users/j...lizzard_46.jpg

http://www.rc-cropduster.com/users/j...lizzard_47.jpg

http://www.rc-cropduster.com/users/j...lizzard_48.jpg

http://www.rc-cropduster.com/users/j...lizzard_49.jpg

http://www.rc-cropduster.com/users/j...lizzard_50.jpg

http://www.rc-cropduster.com/users/j...lizzard_51.jpg

http://www.rc-cropduster.com/users/j...lizzard_52.jpg

http://www.rc-cropduster.com/users/j...lizzard_53.jpg

Together with the Stiletto.
http://www.rc-cropduster.com/users/j...lizzard_54.jpg

Engine and firewall fixed. Needed to modify the firewall and engine bracket to clear the rear exhaust.
http://www.rc-cropduster.com/users/j...lizzard_55.jpg

http://www.rc-cropduster.com/users/j...lizzard_56.jpg

Still quite a lot of space between the wing and exhaust.
http://www.rc-cropduster.com/users/j...lizzard_57.jpg

Joins nice.
http://www.rc-cropduster.com/users/j...lizzard_58.jpg

Cutting a gap with the Dremel. Should be all covered up eventually.
http://www.rc-cropduster.com/users/j...lizzard_59.jpg

Glas gesopt met 30 minuten epoxy. Heeft ongeveer al de juiste vorm, eventueel later met verfstripper bijwerken.
Soaked glass with 30 minutes epoxy resin. Has almost the right shape, maybe needs to be modified with heat gun.
http://www.rc-cropduster.com/users/j...lizzard_60.jpg

Added balsa to accommodate the hinges. The PU glue is foaming great as you can see.
http://www.rc-cropduster.com/users/j...lizzard_61.jpg



I could modify the epoxy plate that I soaked with my bare hands because it was still soft enough. Forced it into place and glued it with 30 minutes epoxy and micro balloons. Satisfied with the result but needs to be sanded afterwards. I'll paint it with some metalic blue paint.
http://www.rc-cropduster.com/users/j...lizzard_62.jpg

Peace of hard balsa glued on the aileron to add more strength for the rudderhorn.
http://www.rc-cropduster.com/users/j...lizzard_63.jpg

Only the control surfaces need to be covered with glass, but the model is almost finished!
http://www.rc-cropduster.com/users/j...lizzard_64.jpg

Viewed from the top.
http://www.rc-cropduster.com/users/j...lizzard_65.jpg


The color scheme I'd had in mind is inspired by a Shockflyer color scheme. I believe it's quite nice because it is very simple and shouldn't be a hard job to paint. I wanted to keep the color scheme simple since I don't have much experience with paint brushing effects. I want to maintain the clear wood instead of the white depron. Should look nice.
http://www.rc-cropduster.com/users/j...olorscheme.jpg


Added some glass to the ailerons.
http://www.rc-cropduster.com/users/j...lizzard_66.jpg

http://www.rc-cropduster.com/users/j...lizzard_67.jpg

To be continued! ;)

RE: Blizzard from Corvidae.net
 

Just one question...: why the hell did you pick the MVVS over the Russian Rossi copy? I mean, the little MVVS is great value if you make a cost/power balance... But if you're going for all out speed, you're better off with an engine like the M+R in the long run, because the MVVS simply lacks brute power/rpm capabilities in stock form...

RE: Blizzard from Corvidae.net
 

Yes I know. ;) But it was lying around here, so I chose the MVVS. Maybe I'll order the M+R later on but first the Blizzard has got to go airborne! All the control surfaces are covered with glass. Only thing resting is spraying paint on the wing and stab.

RE: Blizzard from Corvidae.net
 

Rudeboy,
Do you have a website, contact point for that engine your talking about..

Smitty

RE: Blizzard from Corvidae.net
 

Modellmotorentechnik.de

RE: Blizzard from Corvidae.net
 

Hello,

Very nice plane !

Why did you removed Cylinder head ?
Did you liked this 2.5 ccm MVVS, is it any god and is it really more poverfull
than standard OS / Magnum 2.5 ccm engines ?

How they made this shiny metallic fuselage, is it gelcoat or paint ?

You should make video of first flight :)

Kristijan

RE: Blizzard from Corvidae.net
 

Thanks! ;) I already had the MVVS and I believe it is a good match. Die MVVS has a higher RPM output compared with the OS (I also have the OS .15 CV-A) and Magnum engines, which are more for high torque applications. But beside the higher RPM, I do like the rear exhaust also. Gives a very sleek airframe and reduces drag of course. While building I'd completely stripped the engine to make it easy to fit inside the fuse. It also makes it easier to modify the gap made for the engine and reduces any chance of damaging the blue anodized cylinder head.

The fuse is quite a piece of art. Underneath you can see how the Stiletto fuse is made, for the Blizzard was the same construction method used. The moulds are sprayed with paint and glitter flocks before adding any epoxy resin and glass. It gives a very nice result as you can see.



I'm not going for the M+R on the short term by the way. The OS 50 SX-H from my Raptor 50 needs to be replaced. It did run to hot, so I'm going to buy the 50 Hyper. And since I need to spread my costs I'll stick with the MVVS.

RE: Blizzard from Corvidae.net
 

Hello j0rrit,

throw that stinkin' Master Airscrew into the bin and get you a black Graupner Speed Prop 6.5x6.5 ;) To be then shortened to 5.5" in
diameter.

That makes this little MVVS 2.5 really come alive - if you use a full length tuned pipe (MACS 1110 for instance). The stock black magic muffler is too restrictive. The MACS Pipe length between glow plug and biggest part of the pipe should be set about 21 to 23 cm.

You need to widen the MVVS speed venturi carb up to 6 mm of inner diameter.

Presupposition is that you MUST increase engine exhaust timing up to 170 degrees. Then 25 thousand rpm in flight will be no problem. That makes approx 140 mph with your Blizzard airframe...

Regards

slomo

P.S. The conrod of the UCTKAM .15 = MDS .15 Speed Pylon (or M+R .15 engine rpectively) does not feature a bronze bushing on both ends - just to remember that. :eek:

RE: Blizzard from Corvidae.net
 

Oh, I forgot to mention that any plastic spinner can be very dangerous at rpms exceeding 18 thousand. Highly recommended are precision CNC machined aluminum spinners by Truturn.com (can be ordered through braeckman.de for instance)

RE: Blizzard from Corvidae.net
 

The Master Airscrew was only mounted for display purposes. I had an APC prop in mind, but I'll consider using the Graupner speed prop. Thanks for the tip! I've good experiences with the plastic click-on spinners from Carl Goldberg, unless we're exceeding the rpm-limit. I know. Maybe I'll mount an aluminum spinner eventually, but with the stock engine it's no problem. I've ordered two TruTurn 1-3/4" spinners for the Stiletto's though.

I spoke a Line-Control speed race enthusiast last time and he's using the same MVVS as I do. He'd manage to tune it with a easy solution in my opinion. Using a shimmy of 0,5mm under the edge of the cylinder, the timing is adjusted to 162°. The new timing should already be a big improvement. To keep the compression the same you need to remove the 0,5mm from the top of the cylinder head. That's a job I could do with ease at school. In combination with a APC 6,5x6,5 and 6mm venturi (like you advised also) it was quite an improvement. I'll check the internet for a MACS 1110, I'm curious about the possibilities. ;)

RE: Blizzard from Corvidae.net
 

Good choice, the APC 6.5x6.5 is too thick to keep up with the Graupner Speed Prop.


Yes, that’s good way to avoid remachining the exhaust liner port. To guarantee a well balanced setting of the liner timings, don’t exceed 125 degrees for the booster and the transfer ports. The engine does like 10% nitro fuel at a head clearance of 0.35 mm.

There are many more measures to successfully fine tune the peak rpm of a two stroke engine. But the by far most important one is a matching exhaust ( + liner timing) adjustment. So a correctly set non-muffled full length pipe is a must…

RE: Blizzard from Corvidae.net
 

I messed around a little with an MVVS .15 last year... here are the stock timings I measured on mine:
exhaust 160°
transfers 116°
boost 110°
induction 180° starting 50° ABDC

The head was almost at a whopping 0.5mm [X(]
Slowmo, 0.35mm still seems rather a big gap to me... I was going to go to about 0.20-0.25mm, maybe even less and increase the head volume a little to allow more nitro (don't know about that part yet without more testing). Why do you suggest such a wide squish clearance?

There's definitely room for improvement on this thing.

RE: Blizzard from Corvidae.net
 

Hello Rudeboy,

Yes, I do run considerable smaller head clearance on other 2.5 cc speed engines without problems - using FAI fuel.

I recommend 0.35 mm head clearance for the MVVS 2.5 because staying on the conservative side is better using these MVVS engines (two piece crankcase). Though the gap is quite large for this size of engine there won’t occur problems with overheating. They run reliably and last long with a moderate set compression ratio. More than 26 thousand rpm in flight would not be appreciated anyway. Unfortunately the MVVS 2.5 intake timings are weird, so here are limitations.

Compared to their price these small MVVS engines (2.5 and 3.5 cc) offer great value for the buck. With only little effort you can make them scream - nice for reasonably priced speed planes.

With a fully cowled engine+pipe the Blizzard will be a lot faster!

Regards

slomo

P.S For very satisfying performance of 2.5 to 3.5 cc speed engines, meaning above 35 thousand rpm in-flight, you must use conical glow plugs.

RE: Blizzard from Corvidae.net
 

Well, the building continues. :)

I used a sort of bondo for priming which can be brushed or rolled on. That doesn't give a smooth result, therefore I added some paint thinner and sprayed it on with a spray-canister which can be pressurized.

http://www.rc-cropduster.com/users/j...lizzard_70.jpg

http://www.rc-cropduster.com/users/j...lizzard_71.jpg