Percival Mew Gull

[FEDERICO GILLI]

Hi,

at last the engine is in! I struggle big time to install the filter without having to remove the tank from its location. I used an osullivan "crap trap" that theoretically is suitable for petrol. The two barbed end are a bit short for the tygon tube so despite using tie-wraps I'm not convinced they will stay put with the vibration. Throttle and chake servos are fitted and rod secured I hope this will be it with them as I cannot say was a pleasurable job. The carburettor levers are clearing the muffler with plenty of space left so an other issue is solved.

I also started to look at the electronic injection, hall sensor and plug cable installation. The unit will be secured on the step behind the engine. Wiht the muffler almost touching the rim of the step the hall sensor cable will need to be fed through the big hole in the firewall with the pertol tube. If this cable was an inch longer I could have accomodated the electronic unit in the battery well altogether.

The associated battery will be intalled inside the fuselage in function of the CG requirements. The muffler twin exhoust tubes are only partially clearing the cowl so I need to see if extension are required.

Does not look much but took all evining!

Regards,

 

Federico 

[FEDERICO GILLI]

Sorry I forgot a couple of pictures!

 

Cheers.

[FEDERICO GILLI]

Hi,

 

with the engine finally in place I had to find a place for the motor wiring. I opted to fit the electronic motor management box partially in the battery well with a lot of foam to absprb the vibrations. I used some wrap around sleave for the hall sensor cable as routed very close to the engine block. I hope it is rated for high temperature. I try the cowl on and it does fit well with the exeption of a corner of the muffler so unfortunately Ill have to drill a small hole to avoid the contact.

 

 

 

 

 

 

 

 

Last night I start looking into the wing assembly. The wheel pant supporting blocks got epoxied in and the wheel assembly fitted. On this last point I have to warn you about the screw that retain the wheel to the spring part. These where just screw in and no locktite apply. I pull them out clean up and applied red tread lock to them. I'm still not convinced that is good enough. Also in my kit the retaining saddles for the landing gear were both omitted so I need to come up with a couple. I remove the covering from the wing roots and I dry fitted the aluminium brace. Perfect fit alltogeter. I'll glue them togheter at the weekend... what a shame!

 

Regards,

 

Federico

 

  

[Martin_H]

Federico, check the axles are long enough to do the job. Mine were about 6 mm short - ended up using some 5/16 rod, collets inside the forks and nylon spacers between the collets and the wheels (Dubro 4 1/2"). Was thinking of using Great Planes 5/16 axles instead. What I may end up doing is grinding a groove in the ends of the axle and retaining it with circlips.

 

The wheel sits way too far out - I redrilled the holes in the forks 12 mm shorter but be careful, my units were 3 mm different in length plus I had to tweak one of the wire ends so they aligned when fitted.  My wheel spats were two different heights too... I would love to shorten the spring units too just enough tho hide the axle in the wheel spat but am concerned the spring stroke may be too much and it will bottom out on the spat. I could use a smaller diameter wheel but the Big Balloonies look so right...

[FEDERICO GILLI]

Hi Marty,

 

I'll chek the landing gear indeed. With the exclusion of drillin the prop and spinner backplate to fit the motor 4 bolts assembly  I'have no other progress as I'm after painting a couple of rooms and I'm also stuck with a bit of tileing too.

I'm delaying the assembly of the wing as I do not know where to put it when finished.

Speaking of the final product has anyone weighted theassembled model yet? Will be nice to compare the weights of the different set-ups and see if the cg requirement will level them all.

I hope to do a bit tonight so I might add a couple of picture tomorrow.

 

Best Regards,

 

Federico

 

ps. Marty I can wait for a couple of picture of your mewgull. 

[Graham Ashby (Editor)]

I haven't weighed mine yet Federico although I have balanced it and the model was just slightly tail heavy with the receiver and battery pack pushed as far forward as possible. I'm using a 6V 3200mAh Rx pack (useful weight) which I'm installing within a purpose-built plywood box fixed as far forward as it'll go within the engine bay. I'll get a pic tonight and post it here for interest. Even so, I think I may have to add just a small amount of lead in the nose to get the C of G spot on.

[Les Holloway]

Hi everyone -

Re balancing, mine needs 125g of lead to balance - that's with a 6v battery in the recommended place and the Laser 150. Haven't weighed the beast yet.

 

Meanwhile, can anyone help me find a replacement engine mount similar to the GRP T-bar type supplied in the kit? I chewed mine up in attempting to sort out  the engine / cowl alignment problem, and would really like to start from scratch with a new one.

 

Trouble is, I can't find one big enough - none of my local model shops stock anything suitable, and I've trawled the Internet without success. Perkins can only offer their 120 size metal mount, which is the wrong shape, and anyway Laser Engines strongly advise against metal mounts and prefer GRP. Having had my workshop roof repaired I'm now back in business but completely frustrated by this problem!

 

Cheers - Les

[Martin_H]

Cockpit photos!

 

Alex had really curly hair it seems and I tried unsuccessfully to get the effect.

 

 

Still, he has a purposeful steely determination in his eye and the Cape in sight! The compass points south...

 

I had to work very hard to resist the temptation to make a full depth cockpit. It wouldn't be difficult, the elevator and rudder snakes would need rerouting and there is plenty of aftermarket stuff that would fit. 

 

The pink paper on the cockpit rear bulkhead is a copy of the C of A.

 

 

Edited By Arte et Marty on 19/11/2009 06:11:46

[Graham Ashby (Editor)]

Hi chaps, here's the ply battery box which I'm hoping will serve to shift the weight forward, protect the NiMH from heat and oil (when the box is sealed!), and also offset the effect on lateral balance of having the cylinder hanging out in the breeze. It's almost like I planned it that way! Truth is, it's about the only place I could sensibly fix it to get the weight up front.

 

It's interesting to hear the weight you'll be adding up front Les. I reckon I'm going to need an additional 50 or 60g. 

 

Love the cockpit Martin. Did you have any difficulty getting the old canopy off? 

Edited By Graham Ashby (RCM&E) on 19/11/2009 08:22:25

Edited By Graham Ashby (RCM&E) on 19/11/2009 08:26:15

[Martin_H]

The canopy wasn't too bad, needed a little bit of gentle persuasion and left a little bit of paint behind when it finally let go, however, the canopy touched up easily with some white acrylic paint.

 

Worse was the original pilot, the 'floor' is VERY soft 1 mm balsa and the new pilot hides a rather large hole where the original was solidly glued in place. Hence my near spasm of opening up and detailing the entire cockpit!

 

I would probably preferred a larger pilot, about 30%, the Williams offering to me seems to be a tad too small and the impression of a crowded cockpit that you see in contemporary photos just isn't there.

 

Still, for a stand off scalish model, I am happy with the Gull and will save up the extra detailing ideas for my Flair Tiggie.

 

Just for interest, the pilots harness is simply 3/4" masking tape, folded inwards on itself to 1/4" width and painted with khaki acrylic.    The instrument panel is 3mm ply and the coaming 0.8mm ply. I think the original coaming might have been left a natural timber colour but black works for me.

Edited By Arte et Marty on 19/11/2009 09:06:14

Edited By Arte et Marty on 19/11/2009 09:09:30

[Graham Ashby (Editor)]

I'll bear that in mind when I remove mine. I know what you mean. Unless you go to town on the model it'll only ever be stand-off scale and in that respect you've made the best of the cockpit and improved overall impression, which is just what the model needs. I've bought a Perkins 1/4-scale civilian pilot who, if anything, is a bit bigger than the one supplied in the kit, so I'm hoping he'll fill the space. Gotta fly the model before I get stuck into cockpit detail though.

[FEDERICO GILLI]

Hi all,

 

sorry for the little progress but I got lost in a book!

With the book gone I went back to the building board and I tackle the wing. The two panels joint was pefect so was just matter of protect the two panels with their shipping bags an a little masking tape, mix some 30 min epoxy and voilat!

Two rubber bands were enough to keep the two panels in position and with a bit of methylated spirit the joint was successfully cleand up befor the epoxy cured.

I've also add one additional spacer by side on the motor mount bringing the thrustline closer to the stated one but ckeeping the cowl in line with the top of the fuse. I'm hoping to drill out the exhoust holes tonight so I can get the final cowl position before I start carving the air intake and vent holes. That's the plan anyway.

To the next episode, all the best,

 

Federico

  

[Graham Ashby (Editor)]

No sure if any of you chaps have done any stickering yet but having put some on the fuselage last night I can confirm that they go on beautifully with a drop of soapy water. Not a bubble or blemish in sight... at least, there wasn't when I turned my back on 'em to retire for the evening! I know it's only a stand-off scale model but I still can't bring myself to put the Seagull logo on the spats. One for the flight-box, perhaps?

[FEDERICO GILLI]

Hi Graham,

 

the seagull logo is not going to my spats too!

 

About the stikers.. have yoy cut out all the letters from the transparent background?

Any news on the all up weight?

 

finally I'm after fitting the wheels and thy look awfull, the are obviously two foam sided melted together but the outside rim does not match at all. I'm thinkind to put them on a drill and using sandpaper rectify the issue. Thi is obviously the "strap in cash" optinon! Will be probabily nice to replace them with balloon type if they fit in with.

 

Regards,

 

Federico

 

Regards,

 

 

 

[Graham Ashby (Editor)]

No all-up weight yet Federico - this weekend for sure!  

 

For the practicality of wiping the model down and not catching the corners of the lettering I've used the registration letters en bloc but have cropped them very close to the edge. It's my hope that the Gull will eventually replace my ageing Midget Mustang, which means it'll get flown often and needs to be entirely unfussy to operate, maintain, and clean!

 

My wheels are okay, though I agree, they're not the most expensive I've seen. Spill the beans if you find a quality balloon set before me.

[Geoff S]

An interesting build.  I've always liked the Mew Gull and because of that I bought an unstarted Skyways 1/4 scale Mew Gull part kit on eBay a couple of years ago.  It's still unstarted!

 

The engine specified for the kit is a 0.60 2 stroke!   I've been told they flew well with that engine.  I was thinking of using a 0.90 4 stroke or even a 0.90 stroke but I'd much prefer petrol.  It would seem that your choices of 1.50 Laser and 25cc Roto engines would be more than adequate.  When I first got the kit and was still enthusiastic I looked at fitting one of the cheaper petrol engines and there was no way it would fit sensibly.

 

btw on my petrol engine planes I take 2 pipes out the top of the fuel tank and lead them up and over to the bottom.  They serve as breather and refuelling pipes and are left open in flight.   Joining them with a piece of brass tubing effectively seals them for storage and transport.  No smells either.  The only filtering I use is a felt clunk in the tank and one on my fuel pump.  I use petrol specific tanks (Glen's or Puffin in my case) rather than glow tanks with petrol proof bungs.

 

I'll be interested to see how yours fly.  I guess I'll have to buy the mag to check ot Graham's review.  When is it due?  Or is it confidential?

 

Geoff

[Alan Cantwell]

jUST STARTED MINE,  overall, its pretty impressive,       but i found a problem right away,  i like to drill through the centre of the hinge slot, with a 3mm drill,  then use this to wick cyno into the hinge,     i drilled through the wing trailing edge, to find no hinge retaining blocks,      oh dear,    the hinges at these three points secure to 2.5mm of wood,   this being the trailing edge,  

   I decided to fit these very neccasary safety items,    so simply cut a holein the film, 20x15mm, on the under side, (at the tip, i had to move the hinge slit, because the tip is covered in sheet) fit some 122mm thick soft wood balsa, tacked with cyno, then run some more in the joints,   took 30 minutes for both wings,  take longer if one pulls out--which it will

luckily,  there is opportunity to remove some film from elsewhere to cover these holes,     one other thing i found, was the control surface control horns,     supplied is a pan head screw,   the fitting is countersunk,     being an engineer, i will just knock some off next week,   just to emntion,  all other surfaces where found to have enough meat for the hinges to get a good grip,    

[Martin_H]

Wheels - the Dubro 4 1/2" balloon tyres look pretty good however for weight saving I have fitted the 4 1/2" lightweight Dubro wheels. Contemporary Australia is swamped with American modelling stuff, however, some years ago I obtained some very lightweight wheels from Brian Taylor for his large Mossie plan. They looked very similar to offerings in some Flair kits - RadioActive origin perhaps??? Try Flair's 114 mm dia FL2207C or
127 mm dia FL2208C

Edited By Arte et Marty on 29/11/2009 09:18:53

[Graham Ashby (Editor)]

Hi Geoff, at the moment the only thing holding the review back is this confounded weather. The model's pretty much ready to go although I'll need to make sure the engine is behaving itself before she takes to the air, so there'll be a short period of running in, after which I'll need to get half a dozen flights under my belt before anything's written.

The 4.1/2" Du-Bro wheels sound pretty good, thanks Martin.

I'll keep an eye on the hinges Alan, though they seem pretty firm. 

Edited By Graham Ashby (RCM&E) on 30/11/2009 09:55:56

[Alan Cantwell]

I hope everyone does,  for, unless you do as i did, you would not know your wing trailing edge hinges are only glued into less than 4mm, it needs the hinge securing blocks,  

NOW THEN,    how about this one,     i have found there are 2 undercarraige versions,   mine is a bent 5mm ish piano wire, going into a torsion block, held in with a not supplied saddle clamp--dodgy, i thought,

      Then comes along a forum member, off r/cflyers, who has what i can only describe, as the same mounting system that a re-tract footprint would take, Hmm,

    Then onto the oleos,    the inner, while feeling a good fit, is nothing like,     on the inner cylnder, is fitted top and bottom, in a groove, a crudley made circle of wire--i hesitate to call it a circlip,   the outside diameter of this runs on the bore of the oleo outer,     not even remotley acceptable to a guy who is an engineer for a living,  indeed, one of these orrid bits of wire came out, and wont go back in,  so, the inner compression leg has 1.5mm of clearance!!!      well,   they are at work, and i will make new inners,    its nothing for me to do this,    but, i am wondering what others will find after a landing or 2?? 

 

and make sure the centre bolt, holding the fork is extremely tight,  i found i could twist mine round, and i am going to put a location peg in, to stop this,     

 

dont get me wrong, its a cheap scaleish kit, ideal for what i want,  the faults i can easily put right, mainly because of my occupation,     but, the faults i have listed are real,    and the general public would not know how to put them right,   they will only find out the hard way,

 

i will be contacting the importer,  for i feel these faults need addressing

Edited By ALAN C on 30/11/2009 18:17:43

[Martin_H]

Alan C - kits must vary from time to time or country to country - my trailing edge is fairly hard, as best as I can figure it is at least 6.5 mm, possibly 8 mm thick. I have my doubts too, regarding the wheel units, as I have highlighted previously. Some thoughts as to the 'circlips' - maybe turning up a nylon sleeve instead and locating it using the cap screw,  for the centre bolt I am thinking maybe a hex head bolt and a retainer washer or drilling the cap screw and lock wiring it to the fork. At least if it comes loose the fairing will stop it getting too far off line and the cap screw wont undo and have the gummins fall apart.   In any case, Loctite is essential.

 

[Martin_H]

I really am wondering about joining the wings....double pinned at the front, substantial Joiner, two bolts at the back... I have filled the gap above the wing trailing edge in the fuselage with scrap balsa - gives a positive stop to the wing location without introducing a wing warp by over zealous tightening of the wing bolts.  Hmmm...maybe a liteply plate picking up both wing bolt attachment holes instead of the two washers provided

[Martin_H]

Guess what? The electric conversion doesn't solve the thrust line and cowl problem.... either the firewall has been incorrectly located or the cowl hasn't been manufactured taking the modified thrust line into consideration. 

 

 

The question is, which is correct? The easiest solution is to pack under my engine mount to raise the thrust line to get a neat cowl fit, but what if it needs all that downthrust to fly???

 

 

My kneejerk reaction is to pack the whole thing up and wait to see if Graham can come up with a definitive answer to the flying characteristics. If all that downthrust is there for a good reason then my Gull will not be a very happy camper if I remove some or all of it!

 

 

Now, if someone wants to make a more scale-ish cowl (bit longer, back over the wing root) and compensate for the down thrust then I am VERY interested, chaps! 

So, until someone comes up with the definitive solution, I am off to start on my Flair Tiger Moth...

 

Excuse the photos - camera phone...

Edited By Arte et Marty on 01/12/2009 05:38:33

[Martin_H]

Just measured how much packing I need to bring the thrust line up to in line with a neat fitting cowl - works out at a tad under 2 1/2 degrees. Providing it doesn't go into up thrust territory I could probably live with that...

[Les Holloway]

Hi guys -

 

It's sad to see that Martin with his electric version has the same problem as the rest of us with the thrustline / cowl alignment problem. This does suggest that Seagull haven't got this one right.

 

I have now lashed up a temporary engine mount some 3mm higher than the marked thrustline, and my cowl sits on that quite satisfactorily.  (Not perfectly, just satisfactorily!).

 

Re the undercarriage - It does seem that these vary from kit to kit. I've had none of the problems with length, fit etc reported by others. My set are a bit on the rough and ready side, but are  the right length and work reasonably well. I took them apart and did a bit of filing and greasing before they worked as smoothly as I wanted, and I am not too thrilled by the idea that one Loctited grubscrew stands between me and a landing disaster... but hey! that may be the least of our problems once we take to the skies!