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Old May 22, 2014, 03:08 AM
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How easy a mod is it to get the servos to fit in wings?
Seems the new model has less room in wing for them, is the wing the same thickness as old one and they have just made the servo mount different?
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Old May 23, 2014, 11:47 AM
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Ofcourse the mod is easy. I was just a little annoyed. I'm over it. The tail is slightly warped. But this can also be modified. The maximum thickness of the airfoil is 15 mm. I've compared with pictures online and to me it seems the servo is on the same place in the wing
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Old May 23, 2014, 01:08 PM
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Quote:
Originally Posted by Patatduif View Post
Ofcourse the mod is easy. I was just a little annoyed. I'm over it. The tail is slightly warped. But this can also be modified. The maximum thickness of the airfoil is 15 mm. I've compared with pictures online and to me it seems the servo is on the same place in the wing
I'm baffled. I just checked my wing and it's also 15mm but I did notice that it maintains that thickness from the root to the servo bay and then starts to taper towards the tip. Is it possible that the new ones, or some new ones, start to taper right from the root? I think that would account for the difference and, let's be frank, Chinese planes often have a little variance in their dimensions.

Oh well. The proof is in the air and if you enjoy your Specter as much as I enjoy mine the extra work is well worth it.

Cheers!
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Old May 24, 2014, 05:48 AM
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airfoil

Well that explains it....
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Old Jun 22, 2014, 03:10 PM
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Weight?

I'm interested in the Spectre as my next glider for light slope use. I already have the Speedo II and Ptero-X by R2Hobbies so am familiar with their construction techniques and like how they fly. The Spectre looks like a good next step.

Can I ask what people get as AUW in their Spectres?

I'm looking for a lightweight setup as I only use the motor in emergencies. I am using a 2s setup with a NTM Propdrive 28-26 1000kV[1] swinging a 12x8 on two parallel Nanotech 2s 950 mAh and a 20A ESC in my Ptero-X which works nicely. I would have used a single 950 but couldn't get CG.

I'd probably use the same equipment in the Spectre if the weight could be kept to around 800g.

Thanks!

- Mark

[1] http://www.hobbyking.com/hobbyking/s...dProduct=31699
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Old Jun 22, 2014, 09:02 PM
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Hi, Mark. Please keep in mind that HK is offering a different production run than the Specter I have so there could very well be some differences.

I forgot to weigh mine before I started assembly so I don't have an empty weight for mine. I have a feeling that the 680grams they advertise is not the RTF weight even if one receives a light airframe.

I added some weight by painting the nose and center section. I have a 85 gram motor and 4 HXT900 servos. Light receiver and speed control and a 11X6 carbon prop. When I use a 116 gram battery my RTF weight is 930 grams. It flies very well at this weight. It's not quite a floater but it will exploit light lift while having a wide speed range and I am comfortable flying it in gusts over 20mph. I would call it a very good general purpose glider.

There does seem to be some variation in the weight of the fuselage and I'm glad I have a heavy one. One of my V-tail servos failed and I ended up bouncing off a tree performing a dead drop on the nose from about 20 feet. The only damage was bent wing alignment wires and one wing mounting bolt being pulled through. It's a 15 minute fix plus replacing the servos.

Mine also survived a 11X6 plastic prop breaking at full throttle with no damage to the fuselage!

800 grams might be hard to reach but 830-850 is definitely obtainable and one might be able to shave that down if the vagaries of Chinese QC give you a lighter structure to start with.

Cheers!
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Old Jun 23, 2014, 03:58 PM
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Peter, thanks a lot for your reply. Sounds like your Specter is serving you well.

I do agree that robustness is worth a few extra grams That's one of the reasons I lean towards the Specter/Passer-X rather than the Daemon/Raptor.

Just based on component weights it looks like 850 should be doable with a 2s setup but I doubt one could make CG that way. Well, worth a try.

Guess I'll have to get the next HK order in. ;-)

Thanks!

- Mark
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Old Jun 23, 2014, 04:06 PM
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I think the CG might be doable, Mark. I need to place my 116 gram batteries pretty well back and even when I was using a little 950mah that only weighs around 70 grams I could have moved it forward some more. Plus, the Specter just doesn't seem overly critical about CG. I've moved it 10 mm while looking for optimum and, other than a few clicks of elevator trim, there was very little change in handling.

Cheers!
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Old Jun 29, 2014, 06:48 AM
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Thanks Peter. I have everything on order now. We'll see when it gets here. Should be a fun build if it's anything like the other R2s. Thanks!
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Old Jul 09, 2014, 04:44 PM
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Received my Specter. At first glance the wings seem very nicely built and I think the white and purple cover scheme looks stunning..

Upon further inspection I found that the hardware bag had come unzipped and all the screws and other hardware was flying around inside the box. Dunno if anything escaped through the holes in the corners - at least no wayward screws punched holes in the covering.

More importantly the fuse is really disappointing. First and foremost the wing saddle is not at a 90 degree angle to the centerline of the V-tail saddle. In the first picture the steel angle rests on the wing saddle.

Second the wing saddle exhibits an S-shape longitudinally. I don't think I'll be forcing a built-up wing down into that shape...

The motor mount is only glued on the outside - guess whoever produced this fuse couldn't be bothered putting some on the inside as well.

The totally skewed servo tray is only a footnote. Easy enough to correct since it's shoddily glued in as well.

I have two other R2 planes and I have to say they are miles above this one...
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Old Jul 10, 2014, 06:57 AM
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I'm sorry to hear about your fuselage issues, Mark. Good ol' Chinese QC, or lack thereof, strikes again. But? Let's take stock.

The firewall is an easy fix. I generally add a fillet of epoxy to all formers in a fiberglass fuse. My servo tray was straight but there was no way that a 9gram servo would have fit under the wing so I had to move the servos in front of the tray, where the fuse is a bit deeper, and grind the outside corners off said servos. If I were to do it again i would remove the tray completely and mount the servos on their sides.

Are you certain that the curve in the wing saddle doesn't match the undercamber of your wing? Dry fit your wing and the saddle to be sure. I initially thought mine was a bit off too but it was within the flexing limits of the wing sheeting. I also had to grind some of the gel coat off the inside of the leading edge "pocket". If it's not a match you might still be able to sand it to shape without making it too weak. If it's really off you could shim the trailing edge though you would need a corresponding shim of the V-tail to keep the relative incidence where it needs to be.

The tail might be a bit harder but shouldn't be insurmountable. If there's actually a twist in the fuse then careful working with a heat gun might be all you need. If it's a problem with the molding then a bit of grinding and shimming would do the trick. I ground off the gel coat before I glued on my tail and removed a little extra material from the high side though mine was only off a fraction of a millimeter. Even after that my tail is off a degree or so but I can't even tell except for when I have it hanging on the wall.

I'm not certain that R2 actually makes the Specter. I haven't had a chance to compare the two side by side but there are enough detail differences, like the fuselage being made of thicker glass, that I suspect HobbyKing stole the design. It would be nice if they would charge a few dollars more and take greater pains to eliminate production errors but, since they churn these things out for a song, that might be asking too much.

If all else fails? Carefully place it back in the box and set it aside for a few days. let your mind work on possible fixes and then revisit after the initial disappointment wears off. Then? Let us know if you need any ideas. I still think the design is sound enough that it's worth a little improvisation to get the bird in the air.

Cheers!
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Old Jul 10, 2014, 07:25 AM
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Good advice Peter. I agree it's salvageable just needs a bit of effort and careful planning. I'll take my time with the build, there are a couple of kits in the queue before it anyway. Always have a few unopened boxes in stock for when the mood strikes.

-Mark
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Old Jul 10, 2014, 11:39 AM
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I'm glad to hear you're not discouraged, Mark. I'll try to track down the pictures of bits that I had to modify when I have some extra time.

Cheers!
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Old Jul 16, 2014, 09:49 AM
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Joined Mar 2002
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Joined the Specter Club

I just joined the Specter club. Just got the white/purple version from HK. Been a power pilot all my life and now starting to explore the wonderful world of sailplanes. Been flying a HK E-Fair but looking for something a little more advanced. I'm looking for power/prop suggestions.

Thanks!
Scott
will2fly.com
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Old Jul 16, 2014, 01:36 PM
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Welcome to the club, Scott.

I have switched back to the KDA 22-20L 1000kv with an 11X6 CF prop and a 32mm aluminum spinner. The spinner is a tiny bit oversize but it's not noticeable from 10 feet; 5 feet if I take my glasses off. With this combo and a fairly old 3 cell battery it climbs as high as I like in 10-15 seconds and draws 26amps while delivering 235watts. It doesn't quite have unlimited vertical but it's close. It accelerates indefinitely at 70 degrees.

KDA motors are, as far as I can figure, only available from Giantshark in the UK. I have not ordered from them but their shipping rates seem pretty reasonable. If you would rather sacrifice a little climbing performance to save weight the 22-10S with a 9X5 would still give very passable climb performance. I haven't tried the smaller one myself but I have seen many good reviews on KDA motors ingeneral.

http://www.giantshark.co.uk/search.a...+a22&x=22&y=14

I have also used a HobbyKing 2834 1250kv. It's almost 20 grams lighter than the KDA but has more power and gets a bit warmer. With the HK motor and everything else the same it climbs as high as I like in 8-12 seconds and is even closer to achieving unlimited vertical performance. 75-80 degree climb is still brisk. It draws 32 amps while delivering just over 300watts. I have three of these motors and will be buying more as soon as they are back in stock since I keep breaking shafts and bending bells crashing my 3D foamy. The 2834 and 22-20L are the only 28mm motors I have tried so I can only give a general recommendation if you prefer another brand.

So... Any 28mm motor from 50-80 grams and capable of 175 watts or more should do the trick. Stick around 1000-1300kv and use a prop between 9 and 11 inches in diameter. I like to climb "on the prop" so I use the biggest prop my motor can handle but, if you prefer to "climb on the wing", a smaller prop might suit your style. It's such a clean airframe that it responds quite well to depending on airspeed for climb performance.

Whatever you do; do NOT get a HK "11X6F" folding "precision" propeller. I had two fail in flight and I discovered that they are dangerously defective and full of bubbles that don't show on the surface. After that experience, and having learned what my motors can handle, I have vowed to only use name brand CF blades though, to be fair, my other cheap plastic props have been perfectly fine.

I hope that the vagaries of Chines QC favor you and you have a straight forward build. The worst aspect of my kit was that the provided pushrods were rusty and sticky so I replaced them with 1mm music wire and did a little reaming of the exit holes. One also needs a little ingenuity to fit the servos. Let me know if you run into any problems and I will try to help.

Cheers!
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