Insane Stryker B

[simonh]

I'm starting this thread now tho wont be coming back to it for a good few weeks as the necessary parts will take a while to arrive. Pretty much all Stryker B parts are on special order from the US.

I know, I know - 'hes got 2 strykers why does he need a third??'

The reasons for this project are to see how far the Stryker B platform can be taken with a 3S setup(I have something like 15 3S packs so want to use what I have) and to put into practice some of the stuff I have learned over the last year. I'll be choosing the the parts and doing the setup, assembly, testing and first flight myself. I'll be consulting with Gareth on some issues around the power setup and strengthening the fuselage but the aim will be to do as much as possible myself.

I'll be using a HET 480 size motor. This is a 3300kV motor and has a max power of 700W on 4S. On 3S I estimate it will draw around 40Amps for around 400 - 450W at nominal 10V. This is about a 1000kV more than the Mega motor on my existing Stryker B and the new F27Q. I'll be using a 4.7 x 4.7 prop. It should be easily faster and have more vertical than my current Strykers. It should also be able to take on a Funjet Ultra - but be much nicer to fly.

The assembly of these planes is very simple - so the main issues will be with the power setup I want to use not ripping the wings off or the motor tearing itself from it's mount at full throttle...

This project will be fully costed and all parts used listed in case anyone else wants something mad and fun that they can just chuck in the boot of their car and go fly....

Stryker parts ordered from Wheelspin Models....
F27B Bare Fuselage - unpainted £18.04
F27-C motor mount £6.41. This mount is much wider than the 'B' motor mount - spreading the torque from the motor over a wider area. However, even with this mount, on advice from Gareth,  I'll probably glass the area around the motor mount for added strength
Vertical Fins with tape - £6.89. The fins will be CA'd onto the Fuz
Fin retainer and landing skid £1.89
F27-B complete hatch set - £8.07
F27-B elevons with control horns £3.56

Total for Stryker parts - £44.86

Pushrods and clevises £4.99
The standard Stryker B pushrods and Clevises wont be up to the job - so on Gareth's recommendation I'm going for Irvine carbon fibre pushrods and metal clevises. I got these from Slough models - though here's a link to see what they look like....
http://www.channel4models.com/pushrods-snakes/irvine-carbon-pushrod-set-m2-x-250mm-.html

Motor. 480 size. The can is the same diameter as the mega motor on my Stryker B but it's longer. Will have both more torque and much higher rpm
HET Typhoon 2W-20 3300Kv (700W) Brushless Inrunner Motor.  £59
http://www.brchobbies.co.uk/?page=shop&action=additem&item=387

Speed controller.... I need something small but able to handle 50A to give a good safety margin. Will probably go for a Hacker 55A speed controller. The cheap Hobbyking ones are too bulky for the StrykerB eletronics bay and I dont want to start dremelling out a load of foam - need to keep as much strength in the wing as possible. Price - TBA

Carbon Rods. These will be used to strengthen the wing to stop it snapping in two when pulling max vertical at full throttle.
Size - price  - TBA

That's it for now. First job when the parts arrive will be to give the fuselage a couple of coats of Delux materials EZY-KOTE. This will make the surface of the foam more ding-proof and prepare it for painting.

[Gareth]

having just done the calculations on that motor on 4cells on a 4.7 prop it will have a pitch speed of 217mph
It will also have 162MPH on 3 cells .
the HET motor is going to be about 10% faster than the one going in the pushycat. so it should be good fun and FAST.

Let me know if you want help with any part of this as its going to be mad and sounds like great fun.

Gareth

[andyb]

I was going to stongly suggest that you consider glassing everything when you Eazy-kote it, but mainly the flying surfaces - something like 0.75 oz/sq yard cloth will probably do it - because you don't want flutter at 200+ mph... 

[simonh]

I was going to stongly suggest that you consider glassing everything when you Eazy-kote it, but mainly the flying surfaces - something like 0.75 oz/sq yard cloth will probably do it - because you don't want flutter at 200+ mph... 

Thanks Andy - will do. Gareth was thinking along similar lines. I know nothing about glassing and had no idea what thickness I'd need. I'll pick some up next time I'm in Slough models :D Going to need some help with the glassing tho - or the thing will prob look like the underside of one of those cheap B&Q baths.... 

[andyb]

I know nothing about glassing and had no idea what thickness I'd need. I'll pick some up next time I'm in Slough models :D Going to need some help with the glassing tho - or the thing will prob look like the underside of one of those cheap B&Q baths.... 

No problem, I can show you how its done if you like - it doesn't take long. It'll cost you a cup of real coffee though (i.e. not instant)...

A.

[Mike S]

Mad just Mad Simon.

I like it though it and with the speeds Gareth suggested it should be something to see.

[simonh]

Mad just Mad Simon.

I like it though it and with the speeds Gareth suggested it should be something to see.

It should be fun  Tim's to blame really - he started it all when he sold me the Stryker B wing at the AGM in December last year. There are now actually 5 Strykers in the club and with this new one - 6! Gorber has an F27Q, Tim has a B and...... Gareth enjoyed flying both of mine so much he now has an F27Q as well  We have something in mind for the Tri-Club day on the 17th July - subject to the weather allowing sufficient practice time. I need to check with Chris who will be the competition and flight director for the day but if I get his OK, I'll post something on the Tri Club comp thread.......

[simonh]

After some more thought and discussion with Gareth (who is a thoroughly bad influence    ) during our ironing sessions with the 'CATS it has been decided that it would be a shame not to have the option of using the full 700W from that HET motor......

With that in mind, I'll be fitting a 70A speed controller and will source a couple of compact 4S packs. It will be mainly used on 3S but if I feel the need - the need  for more speed  I'll chuck in  a 4S and spin it up to 50000 rpm. Oh the joy of electric. 700W per pound. mmmmm - even Phil might think thats too much!

The other items to source will be servos. Currently thinking of Metal Geared Hitec's. Dont expect the Stryker B parts to turn up before the end of August.

[phild]

I think that 700w per pound sounds good (in your hands) I certainly don't think I could handle that sort of speed and power.
As a matter of interest I have a couple of 4s batteries for sale, which weigh in at a pound that would slow you down a bit if they would fit.
Phil

[simonh]

I think that 700w per pound sounds good (in your hands) I certainly don't think I could handle that sort of speed and power.
As a matter of interest I have a couple of 4s batteries for sale, which weigh in at a pound that would slow you down a bit if they would fit.
Phil

I think I'll get a bit less than 700W - weighed my existing Stryker B yesterday and it comes in at 1Lb 4oz including the battery. The new one with glass and bigger motor etc will prob be more than 1.5 Lb. Maybe you cld bring the 4S packs to the patch. We can see how they would fit in the battery bay of the one I have. The 4S packs I'm using for the Habu and Fusion are too big.

[simonh]

Have made a start on the mad new Stryker. Most of the time will be taken with painting - assembly is very straightforward.

Decided not to glass it in the end. The foam is pretty tough and I have some special fibre reinforced tape that I'll be using around the motor mount and on the elevon hinge mounts at the wing tips - the foam is thinnest here. This tape will also be used for taping in the servo wires to the bottom of the wing. It can be painted over.

The Stryker wing came with carbon rods preinstalled so that saved me a job.

A coat of EZY-KOTE was painted on the wing to give some extra strength and act as a base for the paint.

I've used Fluorescent red around the leading edge and trailing edge on the top of the wing for orientation. The Fuz area will be painted in high gloss chrome/silver. The tops of the wings will be black. Nose will be black with a chrome silver stripe. All to be painted with Tamiya Acrylics except the fluorescent which is Zuper-paint from Ebay.

The bottom of the wing will have fluorescent blue stripes with black on the Fuz area.

Servos will be HITEC HS-65 with Carbonite gears

I'll need to dremmel out some of the front part of the battery bay for extra room.

I'll be running this on 3S for general flying about  - should be good for around 120MPH. For when I feel the need....., I have found some Rhino 4S 2200 mAh packs that will fit nicely. I used a motor calculator and found that the HET Typhoon 2W-20 will generate around 2Kg of thrust at approx 40000 rpm using a 4.7 x 4.7 prop and will draw 60 amps or so. I think the completed Stryker with a 4S pack will weigh in at 900g or so - plenty of thrust then! It will be running at about 750W at WOT - a bit more than its rated max but as the motor is on the outside, it will get plenty of coolng. That should give me 150MPH+ and should allow Swale and I to have a fun race with his 4S Funjet Ultra 

Parkzone expect you to glue the rear hatch which covers the electronics and the front hatch to the Fuz. I'll be installing dowel in the Fuz and screwing the hatches in for easy removal. Dowel to be glued in with Deluxe Materials Super-Phatic. This makes a stronger and more flexible bond than Cyano. I no longer like using Cyano - too brittle and allows no time for adjustment of a joint.  - will be avoiding it wherever possible from now on. I'll be using foam2foam from Deluxe materials and Superphatic where adhesives are required.

I'll post up again when I've finished the painting.

[phild]

Simon
Just crunching some numbers, at 150 mph will mean that you will cover 100 yards in about 1.4 seconds, convert that to a circuit of probably 700 yards you will certainly need to keep your eyes open, and your fingers moving.
I admire your sense of adventure .
Phil

[Swale]

Simon
Just crunching some numbers, at 150 mph will mean that you will cover 100 yards in about 1.4 seconds, convert that to a circuit of probably 700 yards you will certainly need to keep your eyes open, and your fingers moving.
I admire your sense of adventure .
Phil

Yes lol certainly no time to blink cant wait for this one to come down the patch should be a right laugh.

When do you anticipate the maiden simon?

p.s are you coming down the patch tomorrow/friday afternoon.....I got my bigger prop for the funjet.....hmmm just had a thought I have a spare esc that will take 6s,wonder if the motor will take it

[simonh]

Yes lol certainly no time to blink cant wait for this one to come down the patch should be a right laugh.
When do you anticipate the maiden simon?

p.s are you coming down the patch tomorrow/friday afternoon.....I got my bigger prop for the funjet.....hmmm just had a thought I have a spare esc that will take 6s,wonder if the motor will take it

I think I should have it ready by the end of next week. Had a chat with Gareth about Funjet with the Hacker Motor. Apparently, West London Models hold the speed record for a foam jet using your motor setup and 6S. But - you will burn out the motor after a couple of flights on 6S    A bigger prop will also probably over amp your motor on 4S - be worth it to see how fast it goes tho!

I'll be down tomorrow afternoon with the PushyCat. Andy will be down around 6:30 ish to maiden it with me. See you there......

[Swale]

the funjet came from west london it was the owners

not usre what esc is in it but I have a e flite 60amp laying around I might throw it in.