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Jon Laughton03/10/2014 15:12:42
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1217 forum posts
72 photos

Philip

I still have to build none but this is what I am planning:

Motor: Emax GT4020/09 motor with 5S LiPos (Overlander I think!)

Jon

Biggles' Elder Brother - Moderator03/10/2014 21:08:23
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15748 forum posts
1460 photos

Hi Philip,

I've gone a slightly different route to others I suspect.

1. The motor is an AXI 4120/20 Gold Line - expensive yes, but a lovely bit of kit that will last you years.

2. The ESC is a 70A Black Mantis.

3. The battery is a 6s 3000mAh

4. On the prop I have gone bigger than the recommended, at a 14x6. I think David Ashby was planning on trying a larger prop on his set up as well - but I don't know if he's got round to it yet.

All that gives me very good performance and a comfortable 8-9mins flight time of mixed "scale-like" aeros leaving about 20-25% in the battery.

BEB

PS I forgot to mention, the AXI motor fits in fine using the standard electric conversion kit.

Edited By Biggles' Elder Brother - Moderator on 03/10/2014 21:10:26

Philip Craig03/10/2014 21:37:59
10 forum posts

I was thinking of going with an OS5020-490 (I have one on the shelf so it makes sense to use it is possible) on a 14x7 prop. I can fit a 6S battery but the biggest is only 4000mAh. That is 695g so quite a heavy battery and the motor is 350g. Compare that to what David Ashby used: a 502g battery with a 346g motor. That gives me a heavier front end which is why I'm concerned about the CG. I haven't looked at the weight of the smaller batteries such as the 6S 3000mAh but should do so.

With your setup, are you nose heavy, bang on, tail heavy and did you have to add weight?

Cheers,

Biggles' Elder Brother - Moderator03/10/2014 22:24:00
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15748 forum posts
1460 photos

You might find it a bit tight to fit a 6s 4000 in there. I can just get a 6s 3000 in. The restriction is the fore and aft depth of the battery hatch. You could cut it deeper and make a new hatch but without doing that I'm not sure the 6s 4000 would fit in.

Re the CoG - mine balanced spot on the recommended position with the set up I describe. But as discussed above that recommended position is, I feel, a bit too far forward anyway. So I have about 15g of lead on the tail to just take it back a tad. TBH I think battery weight has very little influence on the CoG position as the battery is pretty well on the CoG anyway.

BEB

Philip Craig04/10/2014 00:25:09
10 forum posts

The size has been the problem. I've been busy making cardboard cutouts of batteries to see which ones would fit and I've found one that is 6S 4000 mAh that would fit...just, in theory, anyway. I might step back to 3700mAh or a 3300mAh to give me a bit more breathing room.

I've also bought a Dubro metal hub tailwheel. It isn't going to add much weight but I'm hoping that due to the distance, the increased moment arm will help compensate, at least a smidgen. Hearing your experience, it doesn't sound like it is going to be enough.

Redex04/10/2014 09:52:47
161 forum posts

Has anybody posted a video of the electric version flying yet.

Redex04/10/2014 10:21:15
161 forum posts

Just wondered for those on electric power, do your motors require standoffs, or just bolt straight on. Thanks

Biggles' Elder Brother - Moderator04/10/2014 12:17:26
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15748 forum posts
1460 photos

I don't have a video of mine flying - I find it a bit tricky to hold the camera and fly the model at the same time wink 2. But I can assure you it will, at the very least, match the flight performance of IC versions and probably outperform many of them!

I used the standard electric conversion kit available as an extra. It uses 4 stand-offs.

BEB

Mr.B.04/10/2014 19:02:46
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413 forum posts
26 photos

Maidened mine today.

dsc_4845.jpg

No problems putting it together. And I think the covering is OK. The 82FS is more than enough power, taking off at half throttle. It was a bit windy and low sun so nothing to adventurous today. Weather looks better tomorrow.

Steve Hargreaves - Moderator04/10/2014 19:06:35
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Moderator
6764 forum posts
197 photos

Love the exhaust trail Mr B.

Good job it is IC powered.....had it been an electric model the smoke would have been seriously worrying.....teeth 2

Whats it like on the Verticals with that engine? Does it keep going or run out of puff after a while? smile p

Mr.B.04/10/2014 19:15:05
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413 forum posts
26 photos

IC? I thought it was steam powered. I haven't wound it out yet, but pulled big loops on just over half throttle.

Mr.B.05/10/2014 20:13:51
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413 forum posts
26 photos

With the 82 verticals are quite strong but not forever. It runs out of puff after about 100ft. Having said that the saito wasn't quite on song. I suspect a small air leak.

Hangar 9 nut11/10/2014 20:11:55
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243 forum posts
25 photos

Thinking of getting one of these I had an original one with a Laser 75 but now would like a bit more power so OS 91,saito 82 or Laser 80 any thoughts on which engine to go for and would a Laser 100 be to much both in weight and size ? all comments would be welcome !

is the weight the same as the original ?

Edited By Hangar 9 nut on 11/10/2014 20:13:27

Mr.B.11/10/2014 20:29:57
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413 forum posts
26 photos

H9, it;s lighter than the original as it has built up wings instead of foam cored. I'm glad a fitted my Saito 82 as I now think the SC90 would have been too much.

Hangar 9 nut12/10/2014 02:31:12
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243 forum posts
25 photos

Thanks Mr B so it looks like a Laser 80 or Saito 82 !

when you say to much do you mean weight or power Mr B !

steve c12/10/2014 06:21:48
20 forum posts

I don't think you could go wrong with either of them the difference in power between a 91 fs and a saito 80 is not really noticeable when the model is flying ,mines got a 91 fs with no lead up front ,and I would imagine the saito 80 has very little lead if any also .

Mr.B.12/10/2014 15:20:57
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413 forum posts
26 photos

I didn't need to add any ballast with the 82 saito and it balances as per the instructions.

I mean don't think it needs any more power. I sorted the air leak out and this morning vertices went on as long as I wanted.

Hangar 9 nut12/10/2014 15:23:44
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243 forum posts
25 photos

Mr B and Steve c thanks very much so any engine heavier than a Saito 82 and you might have to add weight to the tail !

Hangar 9 nut13/10/2014 18:58:18
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243 forum posts
25 photos

Got mine this morning so just need t source an engine now !

Geoffrey Rachel26/10/2014 20:26:07
1 forum posts
  • Hello all, My name is Geoff,new to this forum.Came back to flying about 3 years ago.Have recently recieved my wots wot artf.does anyone know why the electric mounting kit puts the motor off centre

Edited By David Ashby - RCME on 27/10/2014 06:15:27

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