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Durafly EDF Vampire


Seamus O'Leprosy
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Hi Piers,

Like you I thought the dome should be ok but the HK chap was adamant that it is a prime cause of vibration. I don't have a spare receiver to power mine up yet so will have to wait a bit before I see what happens when the electrons hit it. Did you balance yours by adding tape to the inside of the hub?

Colin, I would be interested to know what you find out on your old fan. thumbs up

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Tony, I just gingerly sanded the back of the heavier blades until I got it to balance, probably not very precise but better and it wasn't far out to start with. I can't see the fan on this model being 'way out of balance' or enough to affect the performance significantly. Plenty of power on a 4s 3000mAh LiPo. If you get any reliability problems just ditch the supplied ESC is my 2p worth.

I didn't mind 'Lofty' too much but I did give him a cushion to sit on as he couldn't see where he was going! Nice bit of painting, where did you get him from?

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I completely lost orientation of my EDF Vampire yesterday.
I throttled back to try to sort it out and it headed vertically downwards.
If it had been a balsa plane I think it would have been matchsticks. But this foam can take a good hard knock can't it.
I'm now the owner of a 'Snub Nosed Vampire'.
Somebody said to soak the bent bits with boiling water and they might come back to shape again.
Some people might throw it away at this stage, but I'm sure it'll be fixable.

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I bought one last weekend. Really wanted the silver one, same as the original gate guardian at the original Macclesfield College, which went inside into the Aeronautics dept.

Got the camouflage version, and about to put it together. Not sure about the "no spar" bit, might put a short length of c/f just because I'll won't be just cruising around...devil

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I worried about adding a spar, but didn't bother and have never seen any suggestion in flight that it needs one; I wouldn't bother.

Adding a length of cf down the length of the booms is recommended though. I think I just cut a slot with a blade and a straight edge and pushed a piece of 8 * .5mm in, and glued it with CA.

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Failed! Get it together and fan was waaaay out! Tried to remove it, and broke two blades. An d still stuck tight. Emailed Rapid RC, and will need a new impeller, as it was so wrong, even at minimum throttle, the airframe shook.

How do I remove the edf module without smashing the plan?e - all glued in and tight.

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The trader whom I got it from, Rapid Models said it might be out of balance. I emailed them, and said they'll send me a replacement in the post. They were quite helpful when I made the purchase, and reduced the price of the batteries and other bits I put in.

Hopefully, this might be better, but phoned Tony Hill models, and they've got a Wemotec fan, which probably would be higher quality and balanced. Am I right this is £39 for the fan?

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Paul, the fan unit of my (silver) kit version Vampire was not glued in but held in place with bolts through plastic mouldings. Perhaps HK have reduced their QC on this product line? The Wemotec mini fan pro from Puffin models is priced at £35.95 on their Website. Just make sure you specify the right adaptor for your motor shaft, 2.3mm, 3.2mm or 4mm. I didn't have any problems with my fan unit, perhaps I was just lucky.

I wouldn't bother to add a wing spar as the wing is thick with lots of glueing area, it;s as tough as old boots- I have tested it! . Do reinforce the booms though as Martyn said. Two strips in each boom, one along the underside and the other at 90 degrees on the inside, along the length of each boom terminating mid-chord of the wing. Just make sure the carbon strips are correctly inserted into the slots and you haven't accidently introduced some bend in the booms before you run cyano into the slots. One last point, make sure the servo wires cannot get sucked into the fan!

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As mine's currently in the repair-shop (shed) I've taken the opportunity to remove the undercarriage. I remember being quite pleased to buy my first model with retracting undercarriage, but in use it' snot really worth it, unless you have a tarmac runway or VERY smooth grass. I'll have to find some foam to fill the holes but it'll save a bit of weight.

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Paul, did you get the old fan out ok?

Mine is glued in like yours. I have read that some have bolted a bit of scrap ali bar or similar bent to a 'L' at the end and screwed to the fan casing to get more leverage in order to twist the unit and break the glue bond. Have not tried this myself (yet!).

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Posted by Martyn Johnston on 27/08/2013 08:50

Somebody said to soak the bent bits with boiling water and they might come back to shape again.

That certainly works a treat but don't use boiling water just hot. I repaired a mates foamy he ploughed in (HK AXN) it went from snub nosed and twisted to straight and flyable. Although the foam didn't completely return to its pre-crash state it was very close.

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I broke it, trying to get it out. In the light of it, it was so out-of-balance, I don't think one could recify that. If you take too much off, you get more gap with the fan tip and casing, losing efficiency.

The one coming should be better, failing that, I'll the get Wemitec unit, which is reputibly the Rolls-Royce of fan blades. (pardun the pun!)

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Martyn, when you remove the landing gear don't forget the nose gear is responsible for quite a bit of nose weight, so removing it will move the c of g aft. You will need more weight in the nose as the LiPo won't move any further forward. I used a 3300mAh 4s Lipo which did the trick as well as giving longer flight times.

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  • 1 year later...

Hi all,

I have recently purchased one of the PNF versions of this and wondered if anyone had found it tail heavy??

I have got a 2200 4S LiPo up front and every time i try to balance it (using the 290mm recommendation instead of the 310mm in the manual) it seems very tail heavy.

has anyone else come across this?? i will be either cutting out some of the foam in the nose to push the battery more forward or just add some weight to the nose.

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Hi all,

I have recently purchased one of the PNF versions of this and wondered if anyone had found it tail heavy??

I have got a 2200 4S LiPo up front and every time i try to balance it (using the 290mm recommendation instead of the 310mm in the manual) it seems very tail heavy.

has anyone else come across this?? i will be either cutting out some of the foam in the nose to push the battery more forward or just add some weight to the nose.

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Hi Ben

I have had two of these and neither have been tail heavy - in fact my LiPos have about 1-2 cm clearance in front of them, depending on the LiPo. (Balancing just in front of the booms).

Have you put some CF in the booms? Recommend this very strongly. Lost my first one when it refused to pull out of a diving turn when about to do a low pass. The only explanation we could come up with was that the up elevator I applied not only worked on the plane as a whole, but it also forced the booms to bend down in giving an overall negative AoA for the tailplane - effectively down elevator!

After reading the various forums I have put CF into each boom and never had the problem again - it's a great flyer.

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