Brushless set up for a Great Planes Slinger

[Alex(biggles) Wilkins]

Since having a few go's on a fellow club members Great Planes Slinger, Im hooked and Ive gotto have one!!!  Can anyone recommend a Brushless motor for this Flying Wing, including the Kv rating I was thinkin of putting an Elflite 400 in it.

[scott cuppello]

They are brilliant, but I doubt this motor is a good choice, E-Flight stuff tends to be very middle of the road, and the KV rating is almost certainly too low [probably designed for 8" ish prop], you need speed......you need a high [around 2000kv] motor, 400 size, with a 4-5" prop, around 30A ESC, 2100mAh Lipo 3s......it will be soooooooo quick....but! [Can you tell Iv'e been here!].....good servo's are a must.....killed my last one with a high speed outside loop.....ailerons went into terminal flutter at the bottom of the loop......and couldn't pull out of the loop.......oh dear.

 A 2212/6 400 class out-runner would be spot on [which is 2200kv] or similar, you need to decide on the mount, I used a stick mount [using the brushed motor hollow to get the thrust line spot on], basically a GWS style brushless mount & stick, some epoxy and self tappers.....you are there.

[Alex(biggles) Wilkins]

Thanks for the advice, an eflite 400 has a 4200Kv rating, thats what it says in the specs anyway, but if u recommend a 2200kv ill go for that, im clueless about this, being used to ic flight.  Also i thought ude need to use an inrunner type motor but an outrunner would suit me better being more available on ebay.

P.S. what do you think of this motor http://cgi.ebay.co.uk/Xpower-MP2212-06-Outrunner-Brushless-Motor-2200KV-1-4A_W0QQitemZ270193167745QQihZ017QQcategoryZ34056QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

[Tim Mackey]

I use an inrunner in mine, and found it a little easier to mount -unitl I broke the original ( well actually wifey did but I forgive her ).

I made a new wooden mount, and basically rebuilt the whole thing after that smash which was pretty violent! It is around 5 years old now, and looking its age but still flies great

Scott is right on the mark with his recommendation of about 2000kv - the 4200 KV motor you mention will be really only suitable for very fast EDF units and so on.

[scott cuppello]

Well, hard to say, personally, I give e-bay a wide berth, but each to their own....put it this way, it isn't cheap.

[Tim Mackey]

With so many online retailers of good repute offering suitable motors - why risk fleabay?

[Alex(biggles) Wilkins]

True True, i wouldnt buy a plane off ebay too much chinese rubbish, but u can get the odd bargain here and there.  What motor do u have there? think it says Tornado,

[Tim Mackey]

It is a Tornado 2815-2000 ( 2000 K/V )

[Alex(biggles) Wilkins]

Well Ive ordered the Slinger. Hopefully Santa(postman) will deliver it for christmas, ill post some pics of as i set it up, and i imagine ill have more questions to ask!!

[Bruce Richards]

There is a big parcel sitting under my Christmas tree with my name on it. My guess is that its a Slinger since my son has seen me pondering over it in the LMS. Let us know what you choose for motor ESC battery and servos and how well it works. Bruce

[Alex(biggles) Wilkins]

Has anyone used normal sized servo's on a slinger or could anyone reccomend a brand of micro servo's to use?

[scott cuppello]

You need high-torque sub-micro's, something like the HS55's minimum, maybe even HS65's or equivalent. Don't stick big 'uns in, weight is the enemy of E-Flight! Decent sub-micro's are between 3-5kg pull, the same as decent standard servo's anyway.

[Alex(biggles) Wilkins]

Sorry for the endless questions, ive found a  Feigao Brushless 280L 2550KV from robotbirds.com is that kv ratin a bit high? ive found another which is a bit lower  Feigao Brushless 280S 2100KV 

[Tim Mackey]

2100 better.

[G]

My brushless Slinger flies very well and here's my recommendations:

I used Hitec HS 85-BB servos which work very well.  Hitec HS 65-BBs would probably also be good, but a bit weaker and smaller than the holes for no less cost.  Personally I wouldn't use Hitec HS-55s, I think you're starting to get too weak there.

I use a 2500kV Hacker A20-6XL outrunner.  It works well but mounting it is awkward given that it's an outrunner that mustn't touch the sides.  I reckon the ideal would be an inrunner of the same size as the original motor so you can just strap it in just like the original.  A kV of 2000 would be perfect although 2500 is fine.  3000 or more would be too much, you'd have to fit a very tiny prop to not burn out the motor.  The ideal is t have the biggest prop that fits in between the elevons, and a kV of 2000 or so is right for that.  I'm using a Graupner Speed Cam prop, 5.5 x 4.3, it's a good choice.

I'm using a Hacker 40A ESC but it's a bit big, a smaller 40A ESC would be better (eg Castle Creations or a cheaper brand).  A 30A ESC might be a bit borderline in terms of the setup I'm describing above, which can draw about 30-32A at full throttle. 

The more I fly the Slinger the more impressed I am with it.  It's a bit hard to launch, you need to throw it hard and it needs to be set to have some up elevons.  But it flies really well (and really fast!) and glides well.  And it handles windy days well - now than I'm confident with it I'm enjoying flying it in winds I wouldn't dare launch anything else in.

[Alex(biggles) Wilkins]

Thanks for the advice still waitin for it turn up in the post might not be till after christmas now  ive just bought a couple of HS 65-BBs unfortunatly.

[scott cuppello]

Nowt wrong with the HS65's!

[Alex(biggles) Wilkins]

 t

[G]

From memory the Slinger comes with a 400 size motor which is 28mm diameter I think?  If so, the motor given in the second link would fit better, you could just strap it into the semi-circular space in place of the original without modification.  But it's surprisingly heavy and weak, and not so cheap!  How about this one? -

 http://www.brchobbies.co.uk/?page=shop&action=additem&item=799

It's from BRC Hobbies (who I've bought from before, they seem good), its an HXT 2835, 400 size so I think a perfect fit, it's only £25, it's 2200 kV, it can do up to 32W, ie it sounds perfect.

But I don't have personal experience of this motor, it's just a suggestion, if I were making my Slinger now it's what I would buy.

You'll also need BRC's "3.17mm dome prop adaptor (brc119)" at £2.50 - that's the bit to attach the prop.   

[G]

PS yes the Hitec HS-65 servos will be good.  They're a little bit smaller than the holes in the wings, but that's fine, just stick them in and perhaps add a bit of balsa or foam to hold them securely.

[G]

Three points about assembling the Slinger:

1 - The hardest bit is threading the aerial down the tiny tube!

2 - The Slinger comes with a 'keel' - a wooden bit that sticks down under the plane in the middle - which is an addition to the kit added after the instruction booklet was printed (original Slingers didn't have it).  You definitely need to fit it.  There's nothing to hold on to when you throw it if you don't. 

3 - They say to have the centre of gravity 8 inches back - 8.25 inches is probably better since if it's the slightest bit nose heavy it's too hard to launch - and have the neutral point of the elevons slightly upwards.  Otherwise the plane will hit the ground when you throw it before you get a chance to make it go up.  Remember to throw into the wind and land into the wind so it doesn't land at high speed.  Once airborne, the Slinger is fast but not hard to fly, a lot of fun. 

[Bruce Richards]

I have completed and flown my christmass present. I mounted a brushless outrunner on the back:

Thought you might like to see some pictures.

It flys realy well a bit bumpy in the wind but glides forever.

Bruce 

[Alex(biggles) Wilkins]

Cool! Im in the process of buildin mine, im new to this, so its takin a bit longer, will hopefully have it ready for a test flight next weekend!! putting a 2200kv brushless suggested earlier, gonna try the prop that came with the kit not sure if its suitable but worth a try!

[Tim Mackey]

have you got a whattmeter....or otherwise how will you KNOW that the prop is suitable?

When you burn out your nice new shiny motor and ESC ..then you will know the prop was bit too big

[Bruce Richards]

The prop that comes with the kit is a simple push on job if you plan to use it you will need a proper prop adaptor. The brush less motor has so much toque that it will just spin the motor shaft in the prop.

I totally agree with Timbo on getting a whattmeter I went without for quite a while but has no idea about prop sizing or how badly I was overloading the power train.

Bruce