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AMB 12-05-2012 10:20 AM

back to c/l diesel
 
1 Attachment(s)
Ok group after a month my Sig shoestring finally made it box reads 10-15 size engine it will get the sharma 15 before we risk the Taipan twin BB66, have not flown c/l in decades
will play it safe martin

greggles47 12-05-2012 01:23 PM

RE: back to c/l diesel
 
Martin,

The shoestring is a good flier.

The Sharma will be a good match for it to begin.

Use an 8X5 or 8X6 prop and short fill the tank until the return dizzys abate.

about 50' lines will be about right - should give you about 3-3.5 second laps.

Good luck mate.

Greg

fiery 12-05-2012 02:24 PM

RE: back to c/l diesel
 
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I inherited this "Try-Sickle" stunter along with a whole bunch of C/L goodies including handles, lines, and engines, which due to their being the 'other' form of iginition I will not show. The shade of green of the "Try-Sickle" [:-] is 'interesting'.

It needs a landing gear repair. I will convert it to standard tail dragger configuration, with composite legs bolted to the fuselage, and repair the broken rudder. Apart from these issues it is sound though the venerable Fox .35 it came with is missing a NVA. I have a spare ST style NVA NIP that I am told fits right up.

I will probably re-power it with a .29 ~.35 size diesel anyway, as befits a discerning returning C/L flyer. My old PAW .35 needs to stetch it's legs. I am sure Mr Owen can supply a venturi for it. Or, I could run the 'most appropriate' command economy 5 cc Kometa (ST G21/29 copy) I have. Mecoa/RJL do a Kavan Muffler and adaptor for the ST G21 which i am sure will fit up perfectly.

I also have also received a battered "All American". It is a .30 size old style stunt ship with an ancient offset plug OS bolted to it. It is complete, but will need a complete strip down, and recover. The flaps on it seem to be no longer actuating. Do C/L chaps still use cloth strip hinges these days?


AMB 12-05-2012 02:28 PM

RE: back to c/l diesel
 
Looks like the biggest ( at least longest chore) is sanding the big slab of a wing to correct profile, off subject but did pick up the NIB OS FP 10 today that I got on flea bay, being the chap only lives a few miles away met him and picked up, he liked that , no pack and mail hassle and had it in a half hour not days
good day a plane and engine all in about an hour martin

AMB 12-05-2012 02:39 PM

RE: back to c/l diesel
 
How did the holes in the wing, shape of the gear get there, do not think retracts?? nice project however guess the engine is a Ruskie martin

greggles47 12-05-2012 03:29 PM

RE: back to c/l diesel
 
Martin,

I'm sure volumes have been written about sanding wing sections and all that, but in the end I'm not so sure it matters very much at all.

My recommendation - if you are going to bother with a section at all - is a symmetrical section with the high point at about 35%. This will help stop it wanting to climb into the wind. With the wing area it has you certainly don't need a flat bottomed section. Some people also have a lot of success with a 2/3 - 1/3 section.

Next point use some 1/8" sq spruce as a trailing edge and only shape down to the 1/8. That'll reduce the amount of shaping you need to do and give a stronger wing.

The rub of course is the wing is very thin and not easy to sand to a completely accurate section.

Fiery,

Yes - some do use cloth hinges, but plastic RC hinges are much more common. The cloth to use is the old fashioned cloth tape from the haberdashery (do they still exist??). Glue the tape with C23 Balsa glue.

And boy that is an UGLY big sucker!

Good luck to you both.

Greg

AMB 12-05-2012 03:48 PM

RE: back to c/l diesel
 
GREG Great tip on the 1/8 spruce trailing edge, THX thats a will do-martin
think we can find some cloth for hinge a piece of old bedsheet may do the trick?? they include a strip of thin plastic material looks like clear mylar not the usual stuff you glue in with CA

fiery 12-05-2012 03:53 PM

RE: back to c/l diesel
 
1 Attachment(s)
Martin

They are the (in)famous "Irish Retracts" .

The retract wells are just painted in black enamel on the covering.

The ruined undercarriage mains and nose wheel will all be removed, and the covering re-instated. I won't try too hard to match that nausea inducing colour :).

For cloth strip hingeing, I have looked at the contents of the waxing kits my lady friend buys to attend her grooming requirements (no tasteless comments please gents!).

The cloth strips included would be perfect. Thin, flexible and very strong.

AMB 12-05-2012 03:57 PM

RE: back to c/l diesel
 
I also have some hard plastic pinned hinges martin

fiery 12-05-2012 03:59 PM

RE: back to c/l diesel
 
Pinned hinges are a better option than mylar, I recall C/L hinges need to be as flexible as possible. I am sure the experts here can advise.

steve111 12-05-2012 04:01 PM

RE: back to c/l diesel
 
Hi Fiery, that green thing looks like it might be a bit of fun. I'd have reservations about using a PAW 35 on a slender profile fuselage like that, though, and it will weigh a fair bit more than the Fox. Maybe a good 19TBR instead?

ffkiwi 12-05-2012 04:47 PM

RE: back to c/l diesel
 

Quote:

ORIGINAL: fiery

Martin

They are the (in)famous ''Irish Retracts'' .


and here was me thinking 'Irish Retracts' were those wheels cut from clear Perspex that are complete invisible in flight.................

ChrisM
'ffkiwi'

greggles47 12-06-2012 12:54 AM

RE: back to c/l diesel
 

Quote:

ORIGINAL: AMB

I also have some hard plastic pinned hinges martin
That's what I'd use MArtin.

Glue with Formula 560 or epoxy - but be careful where the epoxy gets. I've managed to glue them up and they quickly became exhinges. :(

pe reivers 12-06-2012 09:11 AM

RE: back to c/l diesel
 

Quote:

ORIGINAL: greggles47

Martin,

I'm sure volumes have been written about sanding wing sections and all that, but in the end I'm not so sure it matters very much at all.

My recommendation - if you are going to bother with a section at all - is a symmetrical section with the high point at about 35%. This will help stop it wanting to climb into the wind. With the wing area it has you certainly don't need a flat bottomed section. Some people also have a lot of success with a 2/3 - 1/3 section.

Next point use some 1/8" sq spruce as a trailing edge and only shape down to the 1/8. That'll reduce the amount of shaping you need to do and give a stronger wing.

The rub of course is the wing is very thin and not easy to sand to a completely accurate section.

Fiery,

Yes - some do use cloth hinges, but plastic RC hinges are much more common. The cloth to use is the old fashioned cloth tape from the haberdashery (do they still exist??). Glue the tape with C23 Balsa glue.

And boy that is an UGLY big sucker!

Good luck to you both.

Greg
I love to do cloth hinges. A handkerchief and cellulose glue will do fine for materials. Absolutely no friction, no torque resistance, and no air leaks through the hinge line!!!! There is no other hinge that can better that.


AMB 12-06-2012 10:03 AM

RE: back to c/l diesel
 
A few years back I did do cloth hinges, I used strips maybe 3/4 inch wide glue on top of stab, bring under and glue on bottom of elevator, then used a 2nd one next to it
that was glued to bottom of stab then up and over and glued to top of elevator , one pair on right and left side of elevator, worked well no slitting of wood and very flexible of course
martin

Recycled Flyer 12-06-2012 01:06 PM

RE: back to c/l diesel
 

Quote:

ORIGINAL: fiery

I inherited this "Try-Sickle" stunter along with a whole bunch of C/L goodies including handles, lines, and engines, which due to their being the 'other' form of iginition I will not show. The shade of green of the "Try-Sickle" [:-] is 'interesting'.

It needs a landing gear repair. I will convert it to standard tail dragger configuration, with composite legs bolted to the fuselage, and repair the broken rudder. Apart from these issues it is sound though the venerable Fox .35 it came with is missing a NVA. I have a spare ST style NVA NIP that I am told fits right up.

I will probably re-power it with a .29 ~.35 size diesel anyway, as befits a discerning returning C/L flyer. My old PAW .35 needs to stetch it's legs. I am sure Mr Owen can supply a venturi for it. Or, I could run the 'most appropriate' command economy 5 cc Kometa (ST G21/29 copy) I have. Mecoa/RJL do a Kavan Muffler and adaptor for the ST G21 which i am sure will fit up perfectly.

Derek, if you are intent on using a PAW 35 then I strongly suggest the use of a 1/2" sheet doubler back to the high point of the wing and (since the PAW is a bigger engine in many ways than one) add some sheet wind tips to gain some wing area. Obviously mounting the engine as far back as possible to help the CG as well.

This of course is assuming that it flies well in the first place with the less powerful Fox.

Good luck!


fiery 12-06-2012 02:20 PM

RE: back to c/l diesel
 
The "peanut gallery" at my local club await my display of fly-by-wire finesse with bated breath ...

There is back-up.

I will have an old C/L flyer by my side to take over if vertigo sets in. For my first flights (I am an optimist using the plural) I will adopt the time honoured practice of "stiff arm" control.

dennis 12-06-2012 02:53 PM

RE: back to c/l diesel
 
Derek, I hope that you and Martin are aware that you can use monokote or almost any film as a hinge also

www.builtrightflyright.com

That takes you to a complete tutorial on how to do it at walts site. Just be aware that it takes a little more effort then R/C flyers usually like to expend on a model, but the results are striking and you have no gap in your surfaces.
You can also use dacron or polyester fabric and they will last forever.

dennis

fiery 12-06-2012 04:18 PM

RE: back to c/l diesel
 
1 Attachment(s)
Received this from Walter just recently Dennis. Also a little Goldberg designed ab initio stunt trainer, the Black Hawk Models rendition of the "Glo-Bee" from 1947. Elevator looks a little large!

I'd have to say the "Comedian" is just about the best 'traditional' kit I have ever had the pleasure to come by.

So how is the "Sakitume" going? Probably not flown yet. Needs a diesel though ;). A diesel head equipped .40 FP would be perfect :D

Jim Thomerson 12-06-2012 05:09 PM

RE: back to c/l diesel
 
I use sewn figure 8 hinges made of dental floss. Cheap, easy, and never wear out.

dennis 12-06-2012 06:44 PM

RE: back to c/l diesel
 
1 Attachment(s)

Quote:

ORIGINAL: fiery

Received this from Walter just recently Dennis.

I'd have to say this is just about the best 'traditional' kit I have ever had the pleasure to come by.

So how is the ''Sakitume'' going? Probably not flown yet. Needs a diesel though ;). An RJL diesel head equipped .40 FP would be perfect :D
I sent you an e mail on the model but this is just to let martin know which model we are talking about. My apologies though it doesn't have a diesel on it.

qazimoto 12-06-2012 09:10 PM

RE: back to c/l diesel
 
1 Attachment(s)
I built a kit Shoestring from the kit as a diesel Goodyear racer about 4-5 years ago. I modified it quite a bit to make it stiffer and to increase it's ruggedness.

It still flies beautifully after only one major rebuild after a prang where the pilot (Greg) had to crash it because of the Nelson diesel going "hard" in flight with the cutout not working.

http://images.rcuniverse.com/forum/u...40/Ay74871.jpg

There's quite a few modifications from the standard model.

http://images.rcuniverse.com/forum/u...40/Fa86036.jpg

The most obvious is the 1/4" square Spruce leading edge and the 1/20" hardwood trailing edge.

A symmetrical airfoil was carefully sanded in with a high point at 30% of root to tip wing chord.

The Tailplane has a core of 1/64" ply, and the fin is three laminations of the same.

Wing, tailplane and fin are all covered in vacuum bagged 3/4 ounce epoxy coated fibre glass.

I always stitch the team racer hinges with Rayon fibre.

Ray

qazimoto 12-06-2012 10:22 PM

RE: back to c/l diesel
 
1 Attachment(s)
I've found some more construction pics.

In order to stiffen and strengthen the fuse I inserted a 1/2" x 1/4" length of spruce.

The model was built for an R250 originally, then got a Nelson 15D and finally a Parra 15 Diesel.

http://images.rcuniverse.com/forum/u...40/Xv64125.jpg

Once the glue dried, the engine bearers supplied were discarded and a longer set were fitted that extended right back to the wing

max thickness position at about 30% root chord.

http://images.rcuniverse.com/forum/u...40/Mh20672.jpg


Two 1/64" ply doublers were fitted to the fuselage front end one at a time so the slot for the wing could be transferred accurately.

The doublers extend well back from the wing trailing edge region to strengthen a problem area for Goodyear Racers.

The engine mounting plate is from 2024 Alloy and is made for R250's.

http://images.rcuniverse.com/forum/u...40/Di10107.jpg

Pic shows LE and TE being fitted. I normally use C23 glue (like Ambroid) for joining the wing bits, PVA for the LE and CA for the TE.

http://images.rcuniverse.com/forum/u...40/Zk67128.jpg

The lot gassing off for a few days.

Not shown is the brass tube and slot in the fuse for a plug in mono-wheel u/c leg. Unlike US Goodyear we can use single wheel/leg undercarriages.

http://images.rcuniverse.com/forum/u...40/Du20518.jpg

greggles47 12-07-2012 01:31 AM

RE: back to c/l diesel
 
That was a beautiful flying model Ray, I was sad to have to ditch it, but I'd rather a crashed model than a burnt out motor any day.

Greg

qazimoto 12-07-2012 02:18 AM

RE: back to c/l diesel
 

Quote:

ORIGINAL: greggles47

That was a beautiful flying model Ray, I was sad to have to ditch it, but I'd rather a crashed model than a burnt out motor any day.

Greg
Ah,

there's another kit still in it's shrink wrap down the shed.

:D


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