Mick Reeves Gangster 63 Lite

[Jonathan M]

One question for the gallery before I sign-off the nose/tank area (which will of course all be fuel-proofed with finishing-resin before final sheeting over):

The cutout in the second former behind the bulkhead is the perfect size to fit the supplied fuel tank, but this doesn't allow for swaddling the tank in foam to help prevent the fuel frothing from transferred vibration. What should I do? Keep it as it is with the tank suspended snugly by the former at the back end and the silicone-sealed neck at the engine bulkhead - or, to allow encasing it in foam, enlarge the former cutout and position the tank slightly further back with just the fuel lines etc protruding?

Jon

[cymaz]

I would embed in foam and hot glue some to the face of the tank.

[Andy Stephenson]

Jonathan,

It's interesting to see how others tackle the same project. I found the trick of getting the fuel tank pipes past the nose-leg wire was to back off the tank by fitting the inner of an insulating tape reel as a spacer. The hole in F1 was made bigger and it was glued in. The bung of the tank fitted perfectly into the spacer. This pushed the tank far enough back whilst still holding it securely as to allow enough clearance to get the silicone pipes to get past the nose-leg. I still had to splay the brass tubes from the tank slightly. I fitted a larger tank than suggested so I had to enlarge the hole in F2 to get it to fit so there wasn't room for padding which, in any case, doesn't seem necessary.

I originally mounted standard size tail servos at the back of the fuz but when I came to check the CoG is seemed too tail heavy so I changed them to mini servos. Now having flown it I am going to put the standard size ones back in one at a time as I now think it's a bit nose heavy.

Andy.

[Jonathan M]

Thanks guys. If I went down the foam route, rather than the 'hard' mount as existing, then:

(1) Surely encasing the whole tank won't be necessary - just where its supported at the bulkhead and the former at the back (with its cutout suitably enlarged)?

(2) The tank would have to be moved back a bit (else the copper pipes snug against the nose-leg would still transmit vibes) and have longer silicone pipes projecting through smaller holes (in a new piece of blanking ply) into the engine space.

With either option (hard or foam mount) I'd still like to be able to remove the tank for any future troubleshooting or repairs.

Andy - interesting how you fine-tuned things due to your bigger engine.  With my mid-weight Irvine 46 I'm mindful of keeping the CG back around 3.75" from the LE to start with.  At this stage I've already started making up solid 1/4" tails and will be adding more structure to the rear of the fuselage, and the battery and receiver will go as far back above the wing-mount bulkhead area as possible.

Edited By Jonathan M on 06/09/2020 11:16:26

[Andy Stephenson]

Jonathan,

I think you will find that the Irvine.46 is actually heavier than the .53 as they are based on the same castings. The .53 is bored out more to accommodate the larger displacement.

Andy.

PS

I just checked there's only 5g in it but the .53 is lighter.

Edited By Andy Stephenson on 06/09/2020 12:31:05

[Nigel R]

A loop of tape around the tank makes a reasonable handle to pull the tank backward out through a wing saddle.

I'd encase the whole tank. Then push the whole lot into place in one go. As cymaz say, hot glue some foam to the tank.

Personally I like SLEC maxi tanks. They make good use of space, are shorter than a standard bottle & bung type tank and the connection points are set back into the body of the tank a little, which can make routing the tubes a bit simpler. Plus, the flat front means the tape loop trick is easy.

[Jonathan M]

Thanks Andy, and Nigel too - good to see you back on this thread!

Good tip re the pull-tape, and on the advisability of encasing the whole tank. I'll now go down the whole foam swaddling route, and move the tank back half an inch so only the tubing protrudes into the tank-bay. Will make up a slightly recessed cover to blank the enlarged neck hole in the bulkhead, then route the tubing through a new small, silicone-sealed hole clear of the nose-leg. I can see it now.

Cheers, Jon

[Jonathan M]

Not much making progress to report in the last week, but today took the opportunity to run up the Irvine 46 with a11x6 prop on the bench and also an alternative suitable engine, the OS Max 46FX, with the same prop. The OS is being used in the Boomerang trainer but I wanted to compare the two power-plants: the OS pulled well topping out at 10,700rpm but the Irvine went the extra distance and really pulled getting up 11,800rpm! So sticking with this as my original choice for the Gangster.

[Jonathan M]

PS: Re the fuel tank, given the very limited space and my wish to not increase the already large former opening so as to encase the supplied 12oz tank in foam, I've just ordered the 10oz version - should still have more than enough juice capacity for 12 minute flights, plus a couple of minutes reserve, which is more than enough.

Edited By Jonathan M on 16/09/2020 22:25:40

[Nigel R]

The Irvine silencer, does it have a baffle?

I found my predecessor OS - the SF - would do about 10k7 on an 11x6 APC, with the standard baffled silencer, but without the baffle it will turn at 11k5.

The baffle makes a reasonable difference to noise, predictably.

[Jonathan M]

Good point, I don't know, will check the Irvine silencer. Its not the original and is an ill fit without a gasket as it leaks visibly.

[Jonathan M]

The OS has a baffled silencer, the Irvine doesn't - hence as you helpfully point out the difference in top RPM.

We don't have noise restrictions at the field, but I'm inclined to order a baffled silencer for the Irvine from Just Engines.

[Mark Jones 10]

Can someone point out where the above mentioned build threads are god this model as I’ve just bought one

thanks

[Andy Stephenson]

Mark,

There's a fair amount of good info in this thread and there's more in this one

A.

[Mark Jones 10]

Posted by Andy Stephenson on 15/11/2020 16:30:19:

Mark,

There's a fair amount of good info in this thread and there's more in this one

A.

 

Thank you Andy. I did search gangster 63 lite but didn’t find the info.
I’m looking forward to building it and using a 55ax up front

Edited By Mark Jones 10 on 15/11/2020 17:02:58

[Andy Stephenson]

Mark the search engine on this site is broken, I have searched for something I know is on here with all sorts of search terms and didn't find it until I went through manually and eventually proved to myself it was there.

[Nigel R]

google does a good job of searching this site - just add "site:www.modelflying.co.uk " in front of the search e.g.

"site:www.modelflying.co.uk gangster 63"

[Jonathan M]

Just a note to say that I'm still progressing my own Gangster - albeit slowly between other jobs - and will post more piccies (and modifications!) in due course.

Never intended to go for the slowest kit-build thread record....

[Nigel R]

[Andy Stephenson]

Unless you are going to fit an engine at the lower end of the specified range (.35) it will be necessary to put some stiffeners in the fuselage structure and beef up the tail surfaces. I used an Irvine .53 in mine and as a result it seemed prudent to make the tail surfaces out of 1/4" sheet instead of built-up. I also installed the rudder and elevator servos in the tail. I started with mini servos but after flying it for the first time I realised that the CG was too far forward which is how it always tends to be, set in a "safe" position by the kit manufacturer. As a result I replaced them with standard servos which cured the problem. Mine came out to 5 1/4 pounds which Mick Reeves claimed was about the weight which the original G63 should have come out at. I can't see how this is possible unless he used much lighter wood than the kits I had in the 70s.

[Nigel R]

You'd be doing pretty well to hit 5-1/4 lb with 70s radio and a 10cc glow. Might be possible - just - if you used the supplied oak-grade balsa as a template for more sensible stuff but that starts making your kit cost "a bit" high.

Maybe the nose needs 1" chopping off to fit a .55?

[Mark Jones 10]

I haven’t got my kit yet as I ordered it Saturday. I’m planning on using an OS 55ax up front. And like the idea above of using 1/4 tail surfaces. Did you use one piece for tail plane ? As when you get a kit it’s planked from a few parts.
I’m going to Sheer web the spar sections and few cross members in the rear also 32nd ply doubler along to just rear of cockpit. Any other suggestions would be gratefully received

Mark

[Jonathan M]

Mark

Re the tail surfaces, I glued the flimsy laser-cut parts together to use just as a pattern for the 1/4" sheet. The tailplane is one piece, plus the sheet elevators which are already supplied.

When you get your kit, do check that the U/C axles are long enough for the wheel hub plus collets - mine weren't so I had to make up new ones!

Finally, I reckon mine will finish up around the 5.5lb mark. With the Irvine 46 this should give me something like 160W/lb. An OS 55AX would turn this into something over 200W/lb - do you need it to hover?

[Paul Marsh]

Don't go on Mick Reeves website, just went on, and the virus checker blocked a Trojan. The website has been hacked.

[Mark Jones 10]

Posted by Jonathan M on 16/11/2020 19:16:59:

Mark

Re the tail surfaces, I glued the flimsy laser-cut parts together to use just as a pattern for the 1/4" sheet. The tailplane is one piece, plus the sheet elevators which are already supplied.

When you get your kit, do check that the U/C axles are long enough for the wheel hub plus collets - mine weren't so I had to make up new ones!

Finally, I reckon mine will finish up around the 5.5lb mark. With the Irvine 46 this should give me something like 160W/lb. An OS 55AX would turn this into something over 200W/lb - do you need it to hover?

Slightly overpowered I know but I only have Irvine 53’s and Os 55. To be honest there aren’t many engines around now there are no asp engines etc

thanks for your advice re tails