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Mick Reeves Gangster 63 Lite


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Jonathan,

Knife edge generally requires power because the required angle of attack of the fuselage puts out so much drag.

My G63 does it with the Irvine 53 so I would recommend it as you have one. This will give you 15% more power and if you can run to a 12 x 6 prop more efficiency too.

Edited by Andy Stephenson
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Plenty of clearance for the 53 to spin a 12x6 with the larger wheels I've fitted ✔️

 

The other thing I'm going to do once the fuselage is back on the bench is see if I can get rid of at least some of the 50g of tail-weight by relocating the battery back one bay from its current spot around the CG mark to its original berth above the wing TE.  Just some rough guesses in my head right now rather than any accurate measuring yet, but moving the 125g NiMh back say 200mm is broadly equivalent to losing 30g (that's an ounce in old money) from the tail 800mm away, i.e.:

 

Battery:  125 (g) x 200 (mm) = 25000

Lead weights:  30 (g) x 800 (mm) = 24000

 

Edited by Jonathan M
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Sounds a good trade off.  

 

Another refinement would be to mount the tank on the CG.  I did this with my Gangster 75.  BUT, you would need a 2 stroke pump to maintain the fuel supply to the engine.  Just Engines sell these pumps but it will require the engine backplate to be removed, drilled and tapped, and a pressure nipple (supplied) screwed in.  It wasn't too bad a job!  Just saying!

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Good idea Peter, and easy enough to fit the nipple, but I'll leave this refinement for a future model where I can plan it in from the outset.

 

Aside from moving the battery back and fitting the bigger engine, all that remains is to scribe in new wing-saddles to fill the surprisingly large gap that's grown (been using masking-tape as a temporary dodge), then I just want to do nothing more except fly it!  (And build the next model!)

 

Although it's quite big, it just squeezes fully-assembled into the back of my car with the seats down (old-style Honda CRV) which is really convenient.  It's easy to clean in the pits (snug fit on the flight-box cradle) with slightly diluted spray de-icer and kitchen-roll, but frankly the combination of exhaust-deflector and Bekra fuel (5 normally but 10 in cold weather) means that there's precious little residue on the airframe.

 

Might stow it (in knife-edge orientation) on the wall... 🤣

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  • 4 weeks later...

A few recent tweaks:


Completed mods to wing-saddle to permanently bring incidence up from -0.8° to +0.7°.

 

PXL_20211229_151548711.thumb.jpeg.3c7a82bfd2ab0e0ab90940f05e3d3687.jpeg

 

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Moved battery back to its original berth above the TE (losing 30 of the 50g I had on the tail, CG still at 111mm).  Changed aileron lead plugs to single Max-Loc connector - much simpler and more secure (it clips in place).

 

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Swapped out original Futaba S3001 tail servos for more powerful Hitec HS485HB units.

 

Re-engined with Irvine 53 on a 12x6 prop - very happy with the extra power (reduced timer from 11 to 10 minutes, using 10oz tank, timer active at over 20% throttle).

 

 

Edited by Jonathan M
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A few photos from yesterday's re-maiden (also with added black trim to wing LE for better head-on visibility).

 

Dry weight now 5.5lbs but still comparatively very Lite, and slows down beautifully for landings exactly where I want to put it down.

 

Extra power very noticeable with, for e.g., knife-edge (not me yet...just when my mate was flying it!)

 

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Edited by Jonathan M
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That's great progress Jonathan.  If you ever feel you need a significant power uplift on the Irvine 53 then a throttle pipe, as shown in the photo below on my Irvine 53 will do that for you.  The Wot 4 is not quite unlimited vertical performance but I can fly very large loops with it!  The prop is an 11*9 as the 12*6 revs went to 13 k!  That would be fine of course but a bit noisy.  The red tape is self amalgamating tape and stops the throttle pipe canister from sounding tinny.  Helps with noise reduction.

 

20200918_141833.thumb.jpg.f32986b7034cbb6cb3166835e30815d3.jpg

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Thanks Peter, useful to have that option in reserve.

 

In the meantime the 53 maxes at 10,000rpm with the 12x6.  More power than the 46 (maxed at 11,000 with an 11x6), although not excessively so:  verticals are better but not completely unlimited.

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The Irvine 53 with standard silencer is usually pretty good at getting through the sound test.  If you are getting a max of 10k rpm, I would aim to up the static rpm by using either a 12x5 or 11x6 prop and see how much more power that releases.  The 53 has peak power at around 15k rpm I think but noise, usually prop, tends to be too much.  That being said, I think my 53 on the throttle pipe and 11x9 prop revs at around 11k rpm static.  I can fly that at one site as we have the rule that if it doesn't sound noisy that's OK.  The other site requires a sound test and I had to prop it down to such an extent that the available power is no better than with the standard silencer.  

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I think the reduction in pitch helps also to get the revs up.  Provided you are not likely to exceed the max power rpm then as you let the engine rev faster you get more power but at the expense of noise.  Don't forget that the prop going fast generates quite a lot of noise.  You lose out on speed as you drop the revs but it's like selecting a lower gear in a car and you can maintain speed on a steeper gradient.

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On 15/01/2022 at 10:02, Jonathan M said:

...In the meantime the 53 maxes at 10,000rpm with the 12x6.  More power than the 46 (maxed at 11,000 with an 11x6), although not excessively so:  verticals are better but not completely unlimited.

I find it surprising as I'm using the same combination of airframe/engine/prop with similar weight and have no trouble with verticals. are you using an APC prop and have balanced it. Could it be the fuel, I use Irvine contest 10.

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Andy, yes the 12x6 is an APC which I've scraped to perfect balance.  Fuel is Bekra (5 normally but currently 10 for the colder weather).  I like Bekra because the residue is much less sticky than the Irvine Sport 5 I was previously using.  Maybe I can lean the high-speed needle a bit more - what kind of top end revs ought I to expect?

 

PS Just to clarify, when I said verticals weren't quite 'unlimited', they are at least pretty good.

 

Edited by Jonathan M
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Jonathan,

 

I meant "unlimited" which is a necessary requirement for competition to do effortless manoeuvres. I'm not sure what revs I'm getting as it was enough to get the performance I was after so I didn't feel it was necessary to measure it. I'm using a UK made Irvine 53 and I notice yours is an OS made version. I cant imagine this would make much difference though. I actually have an OS made one also but I have never used it so I have not compared the two.

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I don't know Ace.  I had a Mk 2 and then bought another and it was the Mk 3 with the natural metal finish carb and that was significantly more powerful than the Mk 2.  Putting a throttle pipe, as in my picture above, cranked up the power once again.  The Mk 3s are cracking engines as well as being pretty quiet with the standard Irvine silencer.

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The reason I asked is that I have several of both and IIRC some internal parts are not interchangeable, not just a different carb which may explain the power difference noticed by Peter.

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Mine is actually ridiculously quiet already on the 12x6 (modern OS muffler fitted) so might give the 11x6 a go... but to be honest my primary focus is now mainly on smoothening my flying and refining the elements of the B Test.

 

She wants to spin right every time, and struggles if I try to force a left spin.  Rolls are lovely individually, just need to ensure I can reliably and repeatedly do two consecutive ones in both directions without screwing out.  Stall turns good, figure of eights fine, learning to blend in rudder at tops of loops and for cross-wind stuff etc.

 

Lovely model for the job.

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Sounds good Jonathan.  If the Gangster wants to spin right then just be led by it.  There is no requirement to spin in a particular direction for the B or for competition.

 

I've just re-propped my Gangster 75 with a 13x8 (it's got a ST 90 on Hanno pipe) but the aircraft is a bit on the heavy side primarily due to the wing!  A built up wing to current F3A practice would make it soooo much lighter.  Still, initial experience with the 13x8 is that its turning at 10,600 and it could go up by 100 rpm as it's just broken into 2 stroking.  That's given it a very much better vertical performance than with the 14x10 that was recommended by a friend - that only reached 8,500 rpm so a gain of 2,000 rpm was pretty significant.  I doubt it will be unlimited vertical but it will fly some quite large loops.  Next thing is to check the noise it generates, which, in the air is fine and quieter than another model with an OS 60 on a pipe.

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10 hours ago, Peter Jenkins said:

I've just re-propped my Gangster 75 with a 13x8 ...  turning at 10,600 ... given it a very much better vertical performance than with the 14x10 that was recommended by a friend - that only reached 8,500 rpm so a gain of 2,000 rpm was pretty significant.  I doubt it will be unlimited vertical but it will fly some quite large loops.

 

Now I know why folk have large propellor collections! 😀

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