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Ian Pullar · Dec 13, 2008, 05:26 AM

For those considering purchasing a Multiplex Blizzard, the following may be valuable food for thought, and may also assist with building.

As well as my own observations, it includes something of a summary of lessons learned from the experiences from contributors to this thread.

The Blizzard is a well designed Multiplex model, made of Elapor, which is similar to EPP, The Elapor in this model is a lot harder and stiffer than Multiplex’s other models.

Span is 1380mm span, which is sufficient to give it stability, yet small enough to facilitate a fast roll rate and make it easily transportable, even if the wing is left attached.

The strength of the Blizzard is seen as a big plus for those who slope soar and who lack a soft landing space.

POWER TRAINS

Multiplex suggests two

Himax HC3510-1100. 250 watt Electric RC Brushless Motor:
KV: 1100, Weight: 89g (3.18 oz)
or
Higher specification motor - Himax 3516-1350 350 watt
KV 1350, Weight: 134g, (4.7oz).

The model is marketed as being for 3 cell lipos, around the 2100 to 2500mah size, however some contributors to this thread are using much hotter combinations and some also 4 cell packs.

HOTLINER OR WARMLINER?

This thread contains a lot of discussion about whether it should be described as a hotliner – or perhaps instead a warmliner.

To some, the distinction seems to be important, to others it is an academic question of semantics, or it really depends on what your definition of hotliner was in the first place.

There has been suggestions of false advertising etc, however in the manual it does state that the plane has limits.

Another view was that advertising this as a hotliner is not important and is little different than batteries being advertised as 30c constant, when experienced users will tell you that many batteries will not last long if used at that rate, so don’t worry about it, let’s just learn what it can and can’t do and get on with the flying. I agree with that view.

The good thing to come out of all this discussion is that it has been established that this model will NOT fly to extremes without modification and while it fills a gap in the market it is not the be-all and end-all of small fast gliders. Potential purchasers need to be aware of the potential for wing flutter if they intend to fly it very hard, and that some other models have better speed retention.

The flutter in high speed dives has been reported particularly by those flying the more powerful and heavier power-trains, and those flying 4 cell packs. However I don’t believe there have been reports in this thread to date of resultant damage. (Please correct me if I’m wrong and I’ll edit this post.)

At our club there are two and neither of us has had flutter despite dives. (Perhaps we’re not trying hard enough!)

A comparable fibreglass model mentioned several times in this thread is the Bandit (see http://www.fvk.de/Englisch/Bandit.html) and also the X-Models Mini Blade Electric (see
http://www.south-coast-sailplanes.co...deelectric.asp
However contributors have acknowledged the Blizzard is less fragile.

HARDWARE

The hardware supplied is excellent and nothing needs to be replaced. In fact, apart from the simple job of adding tape to the wings and having to bend the plug pins, I don’t recall any other suggested modifications (apart from my flaps) or complaints about the quality of the engineering.

BUILDING

Building the model is quite straight forward, simply read the plans 2-3 times, with the bits in front of you, then start building, ticking off each step as you do it.

The instructions suggest the purchase of a Multiplex 6 pin plug-set to fit into wing and fuselage. In fact this is not essential and it is possible to get away with using normal extension lead ends, with the extraction of a little Elapor from the top of the fuselage above the plastic section that’s mounted in the fuselage. If you are not constantly removing the wing then there are no issues with this.

Some who used the Multiplex 6 pin plugs found the need to bend the pins at the bottom, to allow more room for the battery. (I bent them but because I used a light battery, I didn’t need the battery back that far anyway!). Using the extension lead method above would allow more room for the battery and even more could be available if one was to cut back the plug-holder sticking down into the battery cavity, before gluing it in.

Another contributor needed to leave out or cut out the canopy holders from the fuselage to allow him to insert his bigger battery. He held the cover down with tape instead.

My co-flyer broke his canopy hold-downs and instead uses Velcro at the place where it meets the wing, and this was easy and works well.

There are 3 steel ball bearings provided to use a tail weight to correct for centre of gravity. These can be put in after building, by removing a hatch in the tail. (or is it two you can fit in, I can’t remember.)

SERVOS

Various servos have been used successfully.

Hitec HS55s fit perfectly but some of us are not happy with their strength and reliability for this sort of application. For a little extra money you can get the HS56s or, even better (same weight and similar money) the HS65bbs. These are my preference because they are robust, fit into the plane and if I break one I can simply get another from my local hobby shop.

I don’t like having my planes fall from the sky because of an unreliable or under-strength servo failing.

IN THE TAIL – ONE SERVO OR TWO?

One decision you will need to make before you build is whether to have one servo or two in the tail. Two servos will allow you to use rudder (using v-tail in your transmitter or, if your transmitter does not have that facility, requiring a separate v-tail mixer in the model ). At least one contributor chose two servos as even if you felt rudder was not essential, if you had a servo failure the other was likely to allow you to land safely – and there was no extra weight as without the servo you would need one of the ball bearings in the tail anyway. Using a second servo in the tail requires a second lead to come up the tail, which requires a little digging out of the route for the leads, but this can be done easily.

It is possible to add the second servo post-build, provided it does not interfere with the wire of the first servo you put in, and you don’t mind cutting a slit along the fuselage for the wire of the second servo.

Whilst some prefer rudders, many (including myself) find a rudder is not essential as it is not a floater (which would thermal better if the wings were kept close to level). It is a fast flyer and putting it into a bank and pulling elevator is just fine, and quite fun.

SOLDERING

Some soldering of servo extension leads is suggested as being required, however you can get away without it if you simply have the right length extension leads and you dig holes in the Elapor for the plug/socket joins. I did this in the wing and it allows post-build servo replacement to be done without having to re-solder.

Unless you are happy to have your receiver not be accessible after building, have the servo leads that go in the fuselage long enough so they can reach the receiver at the canopy hatch. Then push the receiver all the way back behind the wing.

GLUING IN THE FIBREGLASS RODS

Some contributors say the gluing in of the short fibreglass reinforcement rods onto the wing was difficult. I found it to be the easiest part of the process. The trick I found was thick CA is too thick and thin CA is too runny. Medium CA was fine. I had the leading edge of the wing towards me; I put the medium CA in the groove, I put the cut piece of fibreglass in the groove and pressed down it down at the LEADING EDGE with an implement such as a screwdriver or the back of a knife. (NOT my fingers or I would get glue all over the place). I then used an EYE-DROPPER to drip one drop of accelerator onto the fibreglass at the LEADING EDGE ONLY end. When that hardened a little I held the other end down with a screwdriver and applied a second drop of accelerator, at the far end.

Using this method I completed the job very quickly and with minimum fuss.

It is VERY important that you do this work with PLENTY of ventilation.

ERADICATING FLUTTER

It is important to note that some flyers (myself included) have not had problems with wing flutter. You may choose to do nothing until after a test flight. I suggest you test fly BEFORE you paint, so that any tape you put on can go onto an unpainted surface. (However put some coloured tape on the wings tips before first test flight to ensure you don't lose the plane in the sky. When it's white, it's VERY easy to lose.)

There have been suggested methods of minimising or eradicating flutter by using cross-weave fibreglass packing tape on the wingtips and there is now an additional sheet produced by Multiplex and put into their kits showing how this can be done.

See http://www.rcgroups.com/forums/showt...9#post11035499

A problem with this suggestion is the fibreglass will very quickly go off in the sun and the tape will need to be removed, the wing cleaned and the tape replaced. Covering the fibreglass tape with heat-shrink covering film is likely to be a good solution but as yet there has only been a very small amount if discussion about this suggestion.

However Reflex1 (see his succinct post http://www.rcgroups.com/forums/showt...814980&page=52
post number 766) says he’s solved the problem of wing flutter with NON-reinforced tape.

COLOURING / COVERING / TO BE SEEN AND MAKING IT SLIPPERY

The model can be easily painted. I simply used domestic spray paint cans from my hardware store, allowing thin applications to dry before applying another, to ensure the paint does not run.

I strongly recommend painting or covering using strong colours as it can be VERY easily lost in the sky. I also recommend making the top and bottom different shapes, to help with instant recognition of orientation.

One contributor advised he covered it with heat-shrink film.

I strongly suspect much of the noise it makes when flying fast is from the lumps and bumps of the herringbone fibreglass reinforcement and other spars. I suspect that heat-shrink film may make it more slippery, quieter in the fast fly-by and possibly allow greater energy/speed retention because of less drag at high speed.

If you have any experience in this regard, please share it on this thread.

CENTRE OF GRAVITY

The diagrams show CG 70mm back, which is about half the chord (!). I fly 50mm back.

LANDINGS – SLOWING IT DOWN

Flapperons (ie both ailerons switched up) can be deployed to slow the model down, and this is sufficient speed reduction for some flyers.

I fly at a small field, with trees all around and a relatively small landing area compared to other local radio control flying clubs. I also like slower landings and crow (or butterfly) braking, ie central flaps down and ailerons both up. I achieved this by taping on some 0.5mm aluminium sheet flaps, without having to cut flaps into the wings and potentially weaken the wing structure. This was extremely successful. See http://www.rcgroups.com/forums/showt...7#post11054457

POST BUILD MODIFICATIONS

Almost anything in this plane (possibly excluding the servos) can be easily changed post build. This includes the whole power train, adding or removing tail ballast, strengthening the wing and even and adding flaps.

SO SHOULD YOU BUY ONE?

For me, this plane fills a gap in my range of models, it flies like a rocket and (with flaps) lands like an Easy Star.

RECOMMENDATION

Consider what it is you are seeking.

If you are after a plane that will fly gently and catch light thermals, this isn’t it.
If you are after the fastest hotliner about, this isn’t it.

It lies between the two, but much closer to the hotter end. It is robust, relatively easy to build and flies well if your reactions are good and you keep your wits about you.

If I was going to join in the naming game, I’d call it a pretty hot warmliner, or maybe a slightly cool hotliner.

It will be more forgiving (and a little less hot) if you use a light power-train, and the good news is you can easily upgrade this later.

If you do upgrade it to hot performance it may be necessary to beef up the wings with fibreglass tape as described. However make sure you cover the fibreglass tape, preferably with iron on film. Alternatively, simply try Reflex1’s suggestion of using coloured packaging tape. If it isn’t sufficient for you, simply take it off and try the stronger tape.

If you are a capable flyer and are looking for a speedy but robust model that can grow with your abilities and won’t break the bank then I’d happily recommend it. You won’t be disappointed.

If you are looking for the very best / ultimate performance in a hotliner, and have the skills (and environment and luck) to keep a fibreglass model unscathed, and possibly don’t mind spending a bit more money, then go for a fibreglass model.

Sorry about the length of this article but I hope you find it a helpful summary of the thread so far.

Cheers – Ian P

Dec 13, 2008, 05:26 AM	#775
Ian Pullar Registered User Join Date: Jun 2002 Location: Melbourne Posts: 271	MULTIPLEX BLIZZARD – SHOULD YOU BUY ONE? Thread summary and build tips. For those considering purchasing a Multiplex Blizzard, the following may be valuable food for thought, and may also assist with building. As well as my own observations, it includes something of a summary of lessons learned from the experiences from contributors to this thread. The Blizzard is a well designed Multiplex model, made of Elapor, which is similar to EPP, The Elapor in this model is a lot harder and stiffer than Multiplex’s other models. Span is 1380mm span, which is sufficient to give it stability, yet small enough to facilitate a fast roll rate and make it easily transportable, even if the wing is left attached. The strength of the Blizzard is seen as a big plus for those who slope soar and who lack a soft landing space. POWER TRAINS Multiplex suggests two Himax HC3510-1100. 250 watt Electric RC Brushless Motor: KV: 1100, Weight: 89g (3.18 oz) or Higher specification motor - Himax 3516-1350 350 watt KV 1350, Weight: 134g, (4.7oz). The model is marketed as being for 3 cell lipos, around the 2100 to 2500mah size, however some contributors to this thread are using much hotter combinations and some also 4 cell packs. HOTLINER OR WARMLINER? This thread contains a lot of discussion about whether it should be described as a hotliner – or perhaps instead a warmliner. To some, the distinction seems to be important, to others it is an academic question of semantics, or it really depends on what your definition of hotliner was in the first place. There has been suggestions of false advertising etc, however in the manual it does state that the plane has limits. Another view was that advertising this as a hotliner is not important and is little different than batteries being advertised as 30c constant, when experienced users will tell you that many batteries will not last long if used at that rate, so don’t worry about it, let’s just learn what it can and can’t do and get on with the flying. I agree with that view. The good thing to come out of all this discussion is that it has been established that this model will NOT fly to extremes without modification and while it fills a gap in the market it is not the be-all and end-all of small fast gliders. Potential purchasers need to be aware of the potential for wing flutter if they intend to fly it very hard, and that some other models have better speed retention. The flutter in high speed dives has been reported particularly by those flying the more powerful and heavier power-trains, and those flying 4 cell packs. However I don’t believe there have been reports in this thread to date of resultant damage. (Please correct me if I’m wrong and I’ll edit this post.) At our club there are two and neither of us has had flutter despite dives. (Perhaps we’re not trying hard enough!) A comparable fibreglass model mentioned several times in this thread is the Bandit (see http://www.fvk.de/Englisch/Bandit.html) and also the X-Models Mini Blade Electric (see http://www.south-coast-sailplanes.co...deelectric.asp However contributors have acknowledged the Blizzard is less fragile. HARDWARE The hardware supplied is excellent and nothing needs to be replaced. In fact, apart from the simple job of adding tape to the wings and having to bend the plug pins, I don’t recall any other suggested modifications (apart from my flaps) or complaints about the quality of the engineering. BUILDING Building the model is quite straight forward, simply read the plans 2-3 times, with the bits in front of you, then start building, ticking off each step as you do it. The instructions suggest the purchase of a Multiplex 6 pin plug-set to fit into wing and fuselage. In fact this is not essential and it is possible to get away with using normal extension lead ends, with the extraction of a little Elapor from the top of the fuselage above the plastic section that’s mounted in the fuselage. If you are not constantly removing the wing then there are no issues with this. Some who used the Multiplex 6 pin plugs found the need to bend the pins at the bottom, to allow more room for the battery. (I bent them but because I used a light battery, I didn’t need the battery back that far anyway!). Using the extension lead method above would allow more room for the battery and even more could be available if one was to cut back the plug-holder sticking down into the battery cavity, before gluing it in. Another contributor needed to leave out or cut out the canopy holders from the fuselage to allow him to insert his bigger battery. He held the cover down with tape instead. My co-flyer broke his canopy hold-downs and instead uses Velcro at the place where it meets the wing, and this was easy and works well. There are 3 steel ball bearings provided to use a tail weight to correct for centre of gravity. These can be put in after building, by removing a hatch in the tail. (or is it two you can fit in, I can’t remember.) SERVOS Various servos have been used successfully. Hitec HS55s fit perfectly but some of us are not happy with their strength and reliability for this sort of application. For a little extra money you can get the HS56s or, even better (same weight and similar money) the HS65bbs. These are my preference because they are robust, fit into the plane and if I break one I can simply get another from my local hobby shop. I don’t like having my planes fall from the sky because of an unreliable or under-strength servo failing. IN THE TAIL – ONE SERVO OR TWO? One decision you will need to make before you build is whether to have one servo or two in the tail. Two servos will allow you to use rudder (using v-tail in your transmitter or, if your transmitter does not have that facility, requiring a separate v-tail mixer in the model ). At least one contributor chose two servos as even if you felt rudder was not essential, if you had a servo failure the other was likely to allow you to land safely – and there was no extra weight as without the servo you would need one of the ball bearings in the tail anyway. Using a second servo in the tail requires a second lead to come up the tail, which requires a little digging out of the route for the leads, but this can be done easily. It is possible to add the second servo post-build, provided it does not interfere with the wire of the first servo you put in, and you don’t mind cutting a slit along the fuselage for the wire of the second servo. Whilst some prefer rudders, many (including myself) find a rudder is not essential as it is not a floater (which would thermal better if the wings were kept close to level). It is a fast flyer and putting it into a bank and pulling elevator is just fine, and quite fun. SOLDERING Some soldering of servo extension leads is suggested as being required, however you can get away without it if you simply have the right length extension leads and you dig holes in the Elapor for the plug/socket joins. I did this in the wing and it allows post-build servo replacement to be done without having to re-solder. Unless you are happy to have your receiver not be accessible after building, have the servo leads that go in the fuselage long enough so they can reach the receiver at the canopy hatch. Then push the receiver all the way back behind the wing. GLUING IN THE FIBREGLASS RODS Some contributors say the gluing in of the short fibreglass reinforcement rods onto the wing was difficult. I found it to be the easiest part of the process. The trick I found was thick CA is too thick and thin CA is too runny. Medium CA was fine. I had the leading edge of the wing towards me; I put the medium CA in the groove, I put the cut piece of fibreglass in the groove and pressed down it down at the LEADING EDGE with an implement such as a screwdriver or the back of a knife. (NOT my fingers or I would get glue all over the place). I then used an EYE-DROPPER to drip one drop of accelerator onto the fibreglass at the LEADING EDGE ONLY end. When that hardened a little I held the other end down with a screwdriver and applied a second drop of accelerator, at the far end. Using this method I completed the job very quickly and with minimum fuss. It is VERY important that you do this work with PLENTY of ventilation. ERADICATING FLUTTER It is important to note that some flyers (myself included) have not had problems with wing flutter. You may choose to do nothing until after a test flight. I suggest you test fly BEFORE you paint, so that any tape you put on can go onto an unpainted surface. (However put some coloured tape on the wings tips before first test flight to ensure you don't lose the plane in the sky. When it's white, it's VERY easy to lose.) There have been suggested methods of minimising or eradicating flutter by using cross-weave fibreglass packing tape on the wingtips and there is now an additional sheet produced by Multiplex and put into their kits showing how this can be done. See http://www.rcgroups.com/forums/showt...9#post11035499 A problem with this suggestion is the fibreglass will very quickly go off in the sun and the tape will need to be removed, the wing cleaned and the tape replaced. Covering the fibreglass tape with heat-shrink covering film is likely to be a good solution but as yet there has only been a very small amount if discussion about this suggestion. However Reflex1 (see his succinct post http://www.rcgroups.com/forums/showt...814980&page=52 post number 766) says he’s solved the problem of wing flutter with NON-reinforced tape. COLOURING / COVERING / TO BE SEEN AND MAKING IT SLIPPERY The model can be easily painted. I simply used domestic spray paint cans from my hardware store, allowing thin applications to dry before applying another, to ensure the paint does not run. I strongly recommend painting or covering using strong colours as it can be VERY easily lost in the sky. I also recommend making the top and bottom different shapes, to help with instant recognition of orientation. One contributor advised he covered it with heat-shrink film. I strongly suspect much of the noise it makes when flying fast is from the lumps and bumps of the herringbone fibreglass reinforcement and other spars. I suspect that heat-shrink film may make it more slippery, quieter in the fast fly-by and possibly allow greater energy/speed retention because of less drag at high speed. If you have any experience in this regard, please share it on this thread. CENTRE OF GRAVITY The diagrams show CG 70mm back, which is about half the chord (!). I fly 50mm back. LANDINGS – SLOWING IT DOWN Flapperons (ie both ailerons switched up) can be deployed to slow the model down, and this is sufficient speed reduction for some flyers. I fly at a small field, with trees all around and a relatively small landing area compared to other local radio control flying clubs. I also like slower landings and crow (or butterfly) braking, ie central flaps down and ailerons both up. I achieved this by taping on some 0.5mm aluminium sheet flaps, without having to cut flaps into the wings and potentially weaken the wing structure. This was extremely successful. See http://www.rcgroups.com/forums/showt...7#post11054457 POST BUILD MODIFICATIONS Almost anything in this plane (possibly excluding the servos) can be easily changed post build. This includes the whole power train, adding or removing tail ballast, strengthening the wing and even and adding flaps. SO SHOULD YOU BUY ONE? For me, this plane fills a gap in my range of models, it flies like a rocket and (with flaps) lands like an Easy Star. RECOMMENDATION Consider what it is you are seeking. If you are after a plane that will fly gently and catch light thermals, this isn’t it. If you are after the fastest hotliner about, this isn’t it. It lies between the two, but much closer to the hotter end. It is robust, relatively easy to build and flies well if your reactions are good and you keep your wits about you. If I was going to join in the naming game, I’d call it a pretty hot warmliner, or maybe a slightly cool hotliner. It will be more forgiving (and a little less hot) if you use a light power-train, and the good news is you can easily upgrade this later. If you do upgrade it to hot performance it may be necessary to beef up the wings with fibreglass tape as described. However make sure you cover the fibreglass tape, preferably with iron on film. Alternatively, simply try Reflex1’s suggestion of using coloured packaging tape. If it isn’t sufficient for you, simply take it off and try the stronger tape. If you are a capable flyer and are looking for a speedy but robust model that can grow with your abilities and won’t break the bank then I’d happily recommend it. You won’t be disappointed. If you are looking for the very best / ultimate performance in a hotliner, and have the skills (and environment and luck) to keep a fibreglass model unscathed, and possibly don’t mind spending a bit more money, then go for a fibreglass model. Sorry about the length of this article but I hope you find it a helpful summary of the thread so far. Cheers – Ian P Attached Thumbnails I simply sprayed the wings and tail with spray cans purchased from my local hardware store. 85.6 KB · Views: 434 Underneath I chose a different colour scheme and a different shape. This makes orientation much easier. 113.6 KB · Views: 284 Flaps down, ailerons up, and ready to land. 123.3 KB · Views: 432 Last edited by Ian Pullar; Dec 17, 2008 at 02:36 AM.