[Jamie Duff]

Been quite busy recently and I think I may be allergic to balsa dust 

Today I pre-loaded myself with Piriton and have the hoover handy to sook up dust every time I pick up the sanding blocks.

I've had a visitor this morning too but they were instructed to pass the tools on my command

Underside skinning has started:

[Norfolk'n'Good]

Balsa dust......... really plays me up to    snotty nose, running sore eyes and worse of all a tight chest and coughing wheezing.

[rcfanuk]

Guys, you need to wear masks, sanding in confined places, it's really not good for you

Steve

[Norfolk'n'Good]

I think it's an age thing, never used to bother me but all dust does now    My chest is tight and sinuses blocked after spending the day grinding and welding up SWMBO's firkin MR2 

[Jamie Duff]

I've got some info from Steve Carr about dust avoidance so that's good.

Due to a bit of an oversight on my part I'm more or less stalled until some electrical guff arrives. Some twisted servo cables and 12-way Ashloks are on order, along with 4mm power cable. I've got plenty pneumatic tubing. Once here, these will be installed prior to the last skin going on.

In the mean time I can build the fairings over the spars ahead of the fans, but that's about it 

I weighed the wing as is, and it weighs a whopping 600g  :(. The Mk2 will have some lightening holes in the plywood parts. That said, I think I may have been up to 500g pessimistic on my 'gubbins' estimate, so an AUW of 3kg may still be achievable.

[Tiger]

Been quite busy recently and I think I may be allergic to balsa dust 

Today I pre-loaded myself with Piriton and have the hoover handy to sook up dust every time I pick up the sanding blocks.

I've had a visitor this morning too but they were instructed to pass the tools on my command

Underside skinning has started:

The stuff in the bottle with the pink label on, doesn't help either.....................

Try to have a window open at all times.......................

Tally H 

Andrew

[Jamie Duff]

I've been rather pre-occupied with a 1/48 Canberra tonight, but the fairings over the front spars in the intakes are done, like this:



Looks a bit weird from that angle actually, but they're quite smooth.

Now I have to wait for electrical junk before going any further with the wing.

[Dizz]

Somehow I missed the start of this, but nice one Jamie 
Pete

[Jamie Duff]

My Ashtek order arrived at the weekend, and Tigger returned from Duxford with a load of photos of the IWM's F8 for me. Tigger's photos give good impressions of the aircraft's shape - glancing shots down the fuselage sides etc. These compliment the Fighteraces CD of photo references which give good comparitive measurements of most aspects of Meteors. 

I still have something wrong with me though and have felt grotty for the past week. Yesterday my ears blocked up and I was still awake at 4am listening to the sound of my own blood throbbing through my head. I couldn't get up at 6am when the alarm went off, but I got up at 7 and came to work. I may have to cry off. I could do with taking some leave actually, and if I go home I'll try to get back onto this. The wiring harness for the wing should be a bit of light relief so that might be the way to go.

I hope to have more to show soon.

[wunwinglow]

Hope you soon shake off your lurgi.
You might try inhaling some castor/nitro/synth mix (burnt of course), always works for me.

[Phil Jones]

Great thread, and a good looking model too.
I've been working on a design for an Avro Vulcan with a 70mm EDF and 1100mm w/s, but have had to make some pretty broad asumptions on EDF, motor and battery sizing with respect to wing loading and weight.
Could you elaborate on how you came to the sizing for the meteor? Your weight estimate of 3Kg would suggest to me that you'll need about 1400W from the motor.
 

[Jamie Duff]

Hi Phil,

I've taken an obnoxious approach to this. Rather than work on watts/pound etc, I've chosen a powertrain and sized the model to fit it. I've done a lot of research on fan/motor/battery combinations and come to the broad conclusion that the bigger the fans, the better. Each step up in size (eg 55mm to 65~70mm to 90mm to 110mm) seems to offer a potential step change in unit thrust/unit diameter terms.

I wanted the smallest 6 channel Meteor possible from conventional wooden construction, without deviations from scale outlines. I discounted the 55mm class fans on thrust/diameter grounds. 90mm fans would offer a super Meteor, but the setup I'm using in the Chris Golds 84" Canberra is quite pricey once 8S+ Lipos are counted.

On finding data of numerous Wemotec Minifan 480s producing 15N of thrust using motors costing double figures rather than triple, cell counts low enough to remove the need for expensive HV ESCs etc, I decided to design it around the Minifan.

On the assumption that I may be able to ring out close to 3kg of thrust from the 2 fans, I scaled my 3-view drawings to the Minifan's ideal exhaust size, cross checked the intake size and fan size to ensure they fit the same hypothetical model then mused over whether the weight of the resulting model was in the right ballpark for the thrust.
The size of the exhaust ducts yielded a Meteor 48" in span, which I hoped I could build to around 3kg AUW and have a good thrust to weight ratio for grass take-offs.

Even with an underperforming powertrain, I still think it should fly fine, albeit with poorer vertical performance and a longer run.

I did size up a Vulcan for 4 x Minifan480s on the same principle (exhaust size dictating the scale) but the resulting model would've weighed considerably more than 6kg 

[Phil Jones]

Interesting approach, and very pragmatic. I took a similar one except that I iterated on the size of the model to suit the preferred EDF, with the rule of thumb of 150-200W/lb. Ended up with w/s of 1100mm with a 70mm Velocity WM 400, exiting through the fuse, (with the tail cone removed, so the exhaust nozzle is not scale). The data on the EDF says its optimised for long ducts. Still guessing on motor/battery size. No real proof that the sizing will be right, and no clear info from the web on how to size it scientifically.
Couldn't make multiple fans work for weight/size and cost.

Anyhow, the F8 looks like it'll be a beautiful model. Look forward to hearing how it flies.

[Jamie Duff]

One more thing on the to-do list ticked off.

This is for the inner undercarriage doors, actuated by a single Robart 1/2" stroke cylinder. A Robart valve and micro servo is also going in here somewhere, and the air tank is going in the big fuel tank under the belly.

That means fuselage space is saved, and only the nose gear needs quick connect/disconnet fittings on the pneumatics system.

Would you believe I didn't have a 180deg bellcrank amongst all the junk I have accumulated?  Hence the 1/8" plywood article.





Amazing  I hate the way all this dross eats up all the time. I'm very much a big shapey person rather than a small detail person. Still, better to have all these bases covered now rather than hacking through a wing skin trying to get access to something.

[Jamie Duff]

And the servo/retract valve fitted:



Just wondering if I could get away without a sequencer valve because they're awful expensive...  Perhaps restricting the pneumatic lines to the retract units downstream of the T-piece to the door 'down' and 'up' lines. That should make the door easiest to move down and hardest to move up... maybe. Hmmm shall have to ponder that one and consult the piggy bank.

[Steve_r]

Hi Jamie,

I admire your desire to get every last bit of hardware into this machine....though I have to admit I maybe wouldn't bother so much with the doors on such a model....they can be a B@@tard to setup on a 120+" model let alone a 48" model....hats off to you!

What are your thoughts on the undercarriage legs? Are they going to be machined from ali...or a clever concoction of piano wire? I know from the 'Whittle' that Gloster weren't renowned for making simple undercarrige legs! Why use 1 part when 100 will do!

Looking good so far though...hope to see it in the air this summer?

Steve

[Jamie Duff]

Hi Steve,

The doors are really just an excuse to give up when it gets too hard 

As for undercarriage legs - to be honest I was thinking of just using a single piece of piano wire bent into 'retracted' shape, the maybe dress it up with balsa or similar if the test flying goes ok. The retracted shape of the main u/c isn't unlike the weight-on-wheels shape so I think I'll get away with it. It's far too small to use any of the commercial trailing link units I've seen for sale.

I'm trying to motivate myself for Longhorsely - or rather, shake off this sodding flu so that Longhorsely can motivate me 

[Steve_r]

Well, the weather is looking pretty good so far! Saturday seems the best of the weekend...7mph from the south and no rain!!

See you there?

[Jamie Duff]

Today I have mostly been resting and doing a few neccessary tasks (car exhaust needed changing etc).

All I've managed on the Meteor today is the last wing skin.

I spent a little longer on this one, cutting out the flaps first etc. I wanted to be sure I could separate the flap spar from it's counterpart glued into the wing - so I did it before skinning.



And glued and pinned in place:



Fascinating stuff. Fairly poor for 2 days off work but never mind. I'm feeling a little better so I'm going to Longhorsely 

I've dropped myself in it on Friday night though by volunteering to change a pair of shock absorbers and pair of anti-roll bar drop links on my neighbour's taxi. He used to be a rally driver but now lives alone. He has MS and doesn't keep too well. He's also struggling for money since most of his taxi work involves oily people and they're not travelling much in the current financial climate. I don't know exactly how taxi licensing works but I know he needs his car fixed by this weekend for him to be legal so I thought I could save him the labour charges if nothing else  Anyway, that's a couple of hours on Friday night accounted for...

[Jamie Duff]

Seem to have lost a few posts but it's good to have the forum back!! 

After a super weekend at Longhorsley I've come home with a new pair of HET 69mm fans for the Meteor - perfect fit and will go well with Typhoon 2W-20s on 4S  . I also picked up a single Wemotec 480 Minifan (he only had one) for something which has not yet been decided - maybe a Vampire? Anyway - pickies of the fans in soon 

[Glasser 2008]

Hope I hav'nt missed anything. I think the web site fell over, or was it my p.c.?

Jeff

[Jamie Duff]

It was the website - we lost a few posts from here about Vampires and Meteors but thats all 

[Glasser 2008]

O.K. Jamie, thanks for that. As long as this thread is alright! Was there some good stuff on here re Vampires and Meteors?

Jeff

[Jamie Duff]

You wrote most of it Jeff 

In short no, the site went down late last week, just after you had been posting on it 

[Glasser 2008]

hope it was'nt my fault, most things that go wrong usualy are!

Jeff

[Jamie Duff]

Nah, some unsavoury character(s) hacked into the site server and destroyed everything. It's a new form of cyber vandalism popular with scrotes who haven't got the b*lls to slash car tyres for fear of being dragged into the woods and shot by the owners if caught. Cyber vandalism is 'safe' for cowardly vandals.

Our administrators have been working hard all weekend to rebuild everything, but it seems that the last back-up to rebuild from didn't capture the posts made on the day we were hacked.

[Glasser 2008]

What a sad f****ing world we live in. It does'nt make sense to me that someone with the intelligence (?) to be able to hack into a site and ruin it, could be childish enough to do it. They must lead very lonely lives, as no one knows who they are!
They're obviousely not intelligent enough to be a modeller.

[Jamie Duff]

Newsflash - we weren't hacked afterall, it just broke...

http://www.rcmf.co.uk/4um/index.php/topic,51293.0.html

[Jamie Duff]

Right, where were we?

Last week SWMBO held the wing again to please Flightpack 



The forum went down and dropped a few posts, I went away for the weekend and came back with new fans.

I rechecked my 1/72 scale plans and something didn't sit right with me regarding the nacelles. I'd somehow managed to get the intakes 8mm too wide so these were corrected, which restored the shape of the nacelle plan form which was what bothered me in the first place. Oooops 



I managed to get the N1 and N2 parts cut out (forward nacelle horizontal crutches) then the phone rang as I was stabbing a hole in the leading edge to fit the first one - which put paid to any worthwhile progress. Anyway, here's how the HET fans fit in. There's just under 1mm clearance all the way round the spar hoops and between the bearers. I'm happy with that.





I need to tidy up again. I seem to excel at generating mess. It's quite annoying. I don't even realise I'm doing it.

[half throttle]

I need to tidy up again. I seem to excel at generating mess. It's quite annoying. I don't even realise I'm doing it.

Don't do it Jamie, you know you'll never find anything again!

... and a few scalpel/pliers shaped indentations under the wing always look nice to my eyes. 

[chas smash]

Could you ask your Mrs to hold the wing a little lower next time 

Sorry Ill get my coat 

[Jamie Duff]

  

Once the ducting is built the access to the fairings over the front spar will be very poor - although still very visible. That means I've decided to glass the fairing now before building the ducting and nacelles. The second coat of resin has just gone on...

Meanwhile... (in my best Clarkson voice)

I drew a load of circles on a sheet of plywood and spent a couple of hours with the scroll saw and sander. This was probably the most boring part of the project so far... still, it's done. Laser cut bits would be nice...



Fairings will be primed tomorrow and nacelle building shall commence 

[half throttle]

Nah, laser cutting is for wimps Jamie 

Real men use a broken razor blade. 

[Jamie Duff]

Yeuch... I hate to think how long it would've taken with a Stanley knife and sanding block. 

I'm a devout coward anyway. I'll send you my broken razor blade 

[Jamie Duff]

Right then, the glassed fairings were rubbed down, primed then rubbed down again - nothing ground-breaking here:



The leading edge received a hole in it, as per the real Meteor (Fighteraces photo pack very useful here (http://www.fighteraces.co.uk/ - Under the "Walkarounds" tab) and then reprimed and finally sprayed silver.



It was then simply a case of gluing on all those plywood formers I spent 3 hours of my life cutting out yesterday:







Now I cringe whenever I see self-trumpet-blowing on modelling fora or articles but I think it's starting to look a bit Meteorish now 

The ducting needs to be established using paper templates then cut out from the final material (which will either be 1/64" ply or 0.2mm Proskin, whichever is cheaper) before 3/32" balsa planking is applied. A 1/4" balsa ring will go on the extreme front of the nacelles during the planking to give something soft enough to shape the intake.

Those who are tidy builders will observe that I have a few corrections to make to me nacelle crutch parts on the plans. A sanding block will take care of the prototype though.

[Glasser 2008]

Looking good Jamie, the Meteor is coming along nicely as well!

Could you please get someone else to hold the model, Somehow I keep scrolling back!! Shame you've skinned the wing!!

Jeff

[Winchweight]

Looking good Jamie. It is giving me the nudge to start my Golds Sea Hawk...

[Jamie Duff]

I was just eyeing that plan up again the other day in the Traplet plans book. You already know I think you should go for it 

I understand Chris Golds one flew fine, if casually as a bungee launcher but was a failure with retracts fitted - but that was entirely down to low power of brushed motors and high weight of NiCad packs - it would be a great flier with brushless/LiPo 

[Winchweight]

That's the plan, and it fit retracts.

[Jamie Duff]

YOu could always blow the plan up by 125% and fit your MW54