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Indoor Free Flight Forum => Scale, Indoor => Topic started by: Andrew Darby on December 10, 2017, 01:01:33 PM



Title: VMC Cessna Bird Dog
Post by: Andrew Darby on December 10, 2017, 01:01:33 PM
The next from VMC.

This is my hand cut and rough prototype, I do this to check for how things look and to check for any gross errors before laying out parts for laser cutting.

This was my choice rather than VMC's.  The Sopwith Camel, Triplane, Corsair and Mustang were their choices so I decided to do one that I liked this time.

I like the bird dog, I built the FROG one a few years back, and I have a Guillows kit.  The Guillows kit is tempting but has always dissapointed me, the die cuts are poor and the method of construction is a little too heavy for the size.

The Span is 21" -bigger than most VMC monoplanes, but I think that it needed to be bigger to hit the sweet spot for the methods of construction, fuselage size and wood sizes whilst still being reasonable to handle.  I have given the model a simple "rounded" profile on the lower part of the fuselage.  I haven't gone mad with stringers, just enough to try and pick out the shape.

The tail plane and fin will be built up the sheet ones are just for show.

Next step is to lay out the parts for laser cutting.

Andrew



Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on December 10, 2017, 01:46:21 PM
I can't keep up


Title: Re: VMC Cessna Bird Dog
Post by: danmellor on December 10, 2017, 01:58:13 PM
Very nice. Again! Can we compromise on a Gee Bee Model D, then?!

Tee hee,

Dan.


Title: Re: VMC Cessna Bird Dog
Post by: Pete Fardell on December 10, 2017, 02:27:07 PM
Very nice again! I do like a Bird Dog. Something perky about it.


Title: Re: VMC Cessna Bird Dog
Post by: TheLurker on December 10, 2017, 02:32:30 PM
Count me in.  I built Airfix's non flying 1/72 version of this in nineteen seventy mumble and thought at the time that it was a lovely little aeroplane and your prototype looks just as nice as I remember.  Definitely added to my build programme.


Title: Re: VMC Cessna Bird Dog
Post by: RalphS on December 10, 2017, 02:38:04 PM
Nice to see that you are doing other than KK designs.  I built the Guillow's bird Dog and apart from throwing the super-heavy strip wood away I found it to be a nice light build.  It was initially built for outdoor flying with a large balsa prop and flying right right. I flew it in the velodrome this way although with a new noseblock and smaller plastic prop and it was okay but looked wrong with most of the others circling in the "wrong" direction so I have tried to retrim it to fly left. Still work to do.

Why the all sheet fin and T/P?  

Ralph


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on December 10, 2017, 02:56:32 PM
Hi Ralph,

Nice to see that you are doing other than KK designs.

Why the all sheet fin and T/P?

Ralph

In short I don't, KK nor Veron ever did a Corsair, KK never did a triplane or a Tiger Moth, all of these have been from scratch and three views.  They just follow the "sprit" of the KK and Veron designs.

The sheet parts are just for show as I said in my first post.  if you look closely you will see the layouts of the parts for the built up items.  I just do this to check the over all fit and character...

Andrew



Title: Re: VMC Cessna Bird Dog
Post by: ZK-AUD on December 10, 2017, 03:10:57 PM
Nice Andrew. Sensible size too.  Given the apparent strictness to the plan for KS in the UK will you help them out with a few more stringers around the nose and / or option to infill?


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on December 10, 2017, 03:17:30 PM
Hi ZK,

Yes, the option will be open to in-fill the nose, the plan will show a paper part covering the nose as per normal...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Balsa Ace on December 10, 2017, 04:42:26 PM
Very nice.

Scott


Title: Re: VMC Cessna Bird Dog
Post by: RalphS on December 10, 2017, 05:00:41 PM
In short I don't, KK nor Veron ever did a Corsair, KK never did a triplane or a Tiger Moth, all of these have been from scratch and three views.  They just follow the "sprit" of the KK and Veron designs.

Sorry about that.  I thought that you took the original KK and Veron designs and just made the parts more accurate to aid building.  That the spans of the originals, and the quoted price, of your designs are similar added to that thought.  So if I buy a VMC KK replica kit it won't be the same as your design. The notches can be a bit out and the wing and tail halves can be slightly different although laser cut to the original drawings.

I saw your re-engineered Auster Arrow at the Indoor Nats and thought that it was as I described above and hence to the same KK design as the model that I entered.  It is not listed with the other models that you have designed from scratch but listed with the KK designs.  Is it as the original or modified?

I see that a more bold credit is given to Peter Rakes designs on the VMC website rather than the credit in the text given to your designs again adding to the "cleaned up" design concept.

If you do a Chrislea Super Ace I might raid the piggy bank and buy a kit.  In the meantime I look forward to seeing progress on the Bird Dog and it might encourage me to refurb my version - the Guillows decals all peeled off.  Do the VMC kits use decals now or paper cut-outs?

Ralph







Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on December 10, 2017, 05:50:22 PM
Hi Ralph,

No problem.  The model I flew at the nationals was the Cessna 140, not the Auster.  In profile it is very similar to the KK one, although the structure is quite different.  This was the first model I did for VMC so I stuck with something quite safe shape wise and concentrated on how best to use the laser process to make a simpler/easier construction.  Other than that they are completely different to either the KK and Veron designs.  The sparrowhawk and Osprey sports designs are completely new.  The spans and sizes are similar -as these are meant to carry the spirit of the KK and Veron designs, but with an easier construction parts that fit and removeable nose blocks etc.

VMC still sell the original KK and Veron designs as replica's.  The plans are the same old ones.  I have had a hand in making some corrections to errant parts, but those designs are still as they ever were warts and all!

The ones I have worked on are the "Magnifiecent Flying Machines", I am credited enough on the website, I am effectively the in house VMC designer so was happy enough with the brand name.  I have never sought to call these after myself - it would seem a little egotistical, in the same vein that the KK flying scale ones weren't "Albert Hatfull designs" or the Veron ones weren't "Phil Smith designs"

The decals are paper, however they are available as downloadable files should one want to print them on to decal paper.

Here is the line up.

https://www.vintagemodelcompany.com/magnificent-flying-machines/page/1/

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Jack Plane on December 11, 2017, 03:28:40 AM
Fabo Andrew!  I dimly recall building a Guillow's Bird Dog in the 1970s, probably some time between the toilet-paper shortage and the binmen's strike, but all I can remember of it is the box-art.

Having now built and flown two scale Magnificent Flying Machines kits (and supervised my son building and flying his sports kit), I can say with some experience that the combination of CAD technology with laser-cutting (on good balsa of light and medium-light weight) with highly-accomplished design by Andrew (with inspiration from Phil and Albert) produces excellent flying models - which is what its all about!   ;D



Title: Re: VMC Cessna Bird Dog
Post by: DavidJP on December 11, 2017, 03:31:18 AM
Well this is another “nice one”.  Carrying on the tradition offered by KK and Veron.  Now the youngsters of today can imitate us old lags if they wish and no doubt will find as I did that impatience is the cause of failure but none the less I hope that they will persevere as we did.  They should because the quality of the contents is very much higher and shredding ones finger tips trying to cut box wood with a broken safety razor no longer necessary.


Title: Re: VMC Cessna Bird Dog
Post by: Rudder flutter on December 11, 2017, 08:57:32 AM
Good choice Andrew, As a kid this is one I always wanted to build and wished KK or Veronicas had kitted it.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 13, 2018, 02:51:59 AM
I was pretty poorly over Christmas, I hesitate to say the flu at that is very serious, but suffice to say it was enough to stop me from doing much building, shakey hands aren't great for applying tissue!  BUT I was able to get well ahead with the plan which is pretty much complete.

This means that I have had to Burn the midnight oil in the last couple of weeks to complete the flying prototype before the flying session tommorow at Nottingham.

Pictured isn't my initial mock up as per post number 1, it is the first laser cut set of parts.  VMC are trying to source some darker green tissue for the kit, I have just used whatever I had for this flying prototype.

What you see is around 23g, and it's not too far away from the balance point.  At 21" span this should float around ok.

I have drawn up the scheme markings, if I have time today I will stick 'em on..

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Jack Plane on January 13, 2018, 03:07:35 AM
Love it!  Well done.

Sorry to hear about the cold/flu thing.  My son had the full flu for two weeks over his holidays but is thankfully finally better, and I've been battling a cold for the last week.  I was due to go indoor flying today, and tomorrow looks quite benign for some first outdoor RC action in ages, but I can't risk a relapse.  I have however seen my first Snowdrops and other buds of new life, and can hear birdsong outside the window.  :)


Title: Re: VMC Cessna Bird Dog
Post by: Balsa Ace on January 13, 2018, 06:39:46 AM
That's a great looking Bird Dog,Andrew.

Scott


Title: Re: VMC Cessna Bird Dog
Post by: Kman on January 13, 2018, 07:40:27 AM
Lovely model,

Great attention to detail around windows and daihedral.
Are you going to add wing struts?

Klaus


Title: Re: VMC Cessna Bird Dog
Post by: Yak 52 on January 13, 2018, 08:03:15 AM
That's lovely Andrew - you've captured it spot on  :)


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 13, 2018, 08:20:49 AM
Thanks guys,

Yes Klaus, the struts will be on by the end of the day.

I've just painted the wheels and prop - after giving it a good old scrape to balance it...

Will post some more picture later.

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: abl on January 13, 2018, 11:20:18 AM
That's lovely Andrew - you've captured it spot on  :)

I agree; it's captured the character of the full size.


Title: Re: VMC Cessna Bird Dog
Post by: Pete Fardell on January 13, 2018, 12:17:26 PM
Yup- yet another VMC goody to add to the build list! I was going to ask about the struts too, so am glad they're being added.
See you, and it, at the Harvey Hadden* tomorrow.




* Soon to be renamed the 'Bill Dennis Pratfall Memorial Centre' so I understand.



Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 13, 2018, 02:10:56 PM
Pete... LOL!  :D :D :D. Not laughing at Bill per se, but laughing at the wittiness of your comment...  Are you coming tommorow Bill?  If so I'll hold him down and you can Jab him in the ribs and see how funny he is then!  :D ;D ;D

Well it's done, as much as I'm going to do.  AUW is 25g, with a 1.5 times prop hook to peg length of 3.8mm rubber.  Fast glides on to the bed are good, but I reckon some nasty noseweight will be lumped on tomorrow.

There are a few wrinkles and botches, for a start the glazing is a little dodgy as I tweaked it for the plan patterns, and I managed somehow to get the "marines" one letter out around the peg position making it one further back than it should have been  :-[

I also realised whilst taking the pictures that I missed fitting the inlet on the "chin", you can see it in the pictures...

Andrew





Title: Re: VMC Cessna Bird Dog
Post by: TheLurker on January 13, 2018, 02:25:01 PM
I look at my existing build programme.....

...at the remaining shelf space in my study.....

...the number of moths in my wallet....

... and finally shake my head in resignation knowing that I will be completely incapable of resisting the urge to purchase this kit when it hits the shelves.

It looks spot on and the green tissue colour looks more than good enough for me.


Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on January 13, 2018, 02:54:57 PM
Pete... LOL!  :D :D :D. Not laughing at Bill per se, but laughing at the wittiness of your comment...  Are you coming tommorow Bill?  If so I'll hold him down and you can Jab him in the ribs and see how funny he is then!  :D ;D ;D

Hi Andrew. I´m flying back to Bristol tomorrow but will be driving past the mudslide and hope to call in.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 13, 2018, 04:04:00 PM
Ok, I hope to see you... We'll give that Fardell bloke a good going over... :D

Andrew



Title: Re: VMC Cessna Bird Dog
Post by: Pete Fardell on January 13, 2018, 04:53:03 PM
Hi Andrew. I´m flying back to Bristol tomorrow but will be driving past the mudslide and hope to call in.

Uh-oh, I thought you'd be safely in Spain!











...but if you are coming, how about a re-enactment of the mudslide incident? Some of us missed it the first time and I'm sure it would go down well on YouTube.


Title: Re: VMC Cessna Bird Dog
Post by: Work In Progress on January 13, 2018, 06:00:59 PM
Looks spot on. I think this will do well. It looks like a safe one for relative newcomers, too.


Title: Re: VMC Cessna Bird Dog
Post by: OZPAF on January 14, 2018, 07:13:11 AM
Another fine effort Andrew. Uneven rib spacing in the stab - front and back of the main spar seems to be your trade mark. Why exactly do you like it like that?

Good luck with the maiden flights.

John


Title: Re: VMC Cessna Bird Dog
Post by: Jack Plane on January 14, 2018, 07:53:02 AM
Because weaknesses in the spar at each notch-point are reduced by separating them?


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 14, 2018, 01:58:55 PM
- Yup!  Spot on Jon...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 14, 2018, 02:50:08 PM
She flies.

Nice and slow too.  This is one of the trimming flights with around 600 winds  I was happy enough with this today, and put it away before I "improved" (broke) it...

https://youtu.be/MxALvGRB-wM

It needed a bit of noseweight, but not much.

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Tim Horne on January 14, 2018, 03:11:57 PM
Very nice indeed!


Title: Re: VMC Cessna Bird Dog
Post by: ffkiwi on January 14, 2018, 03:21:23 PM
Andrew-any indication of when the Bird dog kit will be available?

 ChrisM
 'ffkiwi'


Title: Re: VMC Cessna Bird Dog
Post by: danmellor on January 14, 2018, 03:47:35 PM
That looks fantastic! So annoyed I couldn't make it today.

Cheers,

Dan.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 14, 2018, 04:01:19 PM
Cheers guys...

Not sure exactly Chris.  I have the photo quality one to build, plus writing the instructions.  I am also away with work soon.  If I had to have a stab at a date I reckon it will be mid March...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: FreeFlightModeller on January 14, 2018, 04:13:13 PM
Lovely flight ... especially for an early one.
I was also annoyed that I couldn't make it today.


Title: Re: VMC Cessna Bird Dog
Post by: Snaky Stringer on January 14, 2018, 04:48:50 PM
Beautiful flight and landing especially so.


Title: Re: VMC Cessna Bird Dog
Post by: Pete Fardell on January 14, 2018, 05:15:50 PM
It looked great! A very nice representarion of the Bird Dog, which to my mind definitely has a certain something which other high wing monoplanes don't. Here's my own vid of the same flight. (It's not nearly as good quality, but at least the angle's different.)
https://m.youtube.com/watch?v=RTfd9q4hNm8


Title: Re: VMC Cessna Bird Dog
Post by: OZPAF on January 15, 2018, 12:53:52 AM
[quoteBecause weaknesses in the spar at each notch-point are reduced by separating them?][/quote]

Thanks Jon and Andrew - that makes sense. The glue at each joint probably makes a reasonable stress riser - more so with light balsa. Another probable good reason to not use much CA.

Very nice slow flight Andrew - amazing for it's first outing.

John


Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on January 15, 2018, 03:39:57 AM
I dropped in to see what was going on and was mightily impressed with the Bird Dog. Slow-flying and stable, with scale dihedral. It's a very low-drag design.
It's a nice meeting and needs a lot more support.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 15, 2018, 06:19:59 AM
TBH I though I'd fouled up on the dihedral when I built it, but when I measured it it was fine.  It is pretty well much scale, but looks less than it is (as does the real thing). There is a weird optical illusion with it.  Because the cabin sides taper inwards top to bottom it makes the angle look less that it is...

Yes we suffered again yesterday, the hall was £200 and 8 filers at £10 a pop meant a £120 deficit from the club bank account...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Jack Plane on January 15, 2018, 06:49:17 AM
Sorry to hear about the deficit.  Maybe more people (or people they care for) are currently hit with one of the vicious colds or the big flu that's currently about?

The monthly indoor meeting at Newbury (which I missed on Saturday due to aforementioned lurgy) is split between RC and FF, with separate alternating half-hour slots.  This helps keep it economic for all, but to be honest it normally takes most of each half hour to even begin to get a model trimmed and then I find I've lost my 'flow' when the next FF slot comes up!  Or I incur damage to the model at the start of the slot and waste the rest of it doing repairs!

Its all just too intense!  Now, where's the nearest 'safe-space' to go and lie down...?   :o


Title: Re: VMC Cessna Bird Dog
Post by: ffkiwi on January 15, 2018, 04:00:02 PM
Cheers guys...

Not sure exactly Chris.  I have the photo quality one to build, plus writing the instructions.  I am also away with work soon.  If I had to have a stab at a date I reckon it will be mid March...

Andrew

That's good-in other words few months time. Not too long to wait.

ChrisM
'ffkiwi'


Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on January 16, 2018, 08:31:47 AM
Today I went to the model shop in Nottingham. The walls were festooned with all sorts of FF kits - Guillows, Westwings, Aerographics, etc. I asked the chap why they didn't stock the VMC range. When he finally understood what I was talking about, he said they couldn't get them. I looked incredulous, and he explained that they depend on suppliers - middle men - to bring them what they have.
How naive am I. I assumed that a shop, realising that the VMC range are far better quality and value, would call VMC direct and ask them to send kits. At that point I realised why the model shop sells  British wire that doesn't fit American tubes.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 16, 2018, 11:11:10 AM
Strange!

When i was up at the VMC works in the summer they were working on a really nice display/presentation box thing with a pop up at the back - all to make it easy for the shops!  If this is Gee Dee's I thought Paul Briggs had bought one form there so I am surprised?

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on January 16, 2018, 12:03:51 PM
Andrew; about 18 months ago they had a very few - Tiger, Spitfire... They never had an SE5 and nothing since.


Title: Re: VMC Cessna Bird Dog
Post by: Nigel Monk on January 16, 2018, 04:37:07 PM
It looked great! A very nice representarion of the Bird Dog, which to my mind definitely has a certain something which other high wing monoplanes don't. Here's my own vid of the same flight. (It's not nearly as good quality, but at least the angle's different.)
https://m.youtube.com/watch?v=RTfd9q4hNm8
Nicely parked at the end.


Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on January 19, 2018, 04:34:30 AM
Here is Paul Briggs' version of an old Mike Hetherington design. Mike made many models, like this, out of pre-painted paper. His best was a Stosser.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 19, 2018, 01:04:52 PM
It's a remarkable piece of kit that, there is a bit of balsa in it, but not a lot.  The paper is stiffened very effectively by creating ribs in it.

I have the plan to scan in, when I get chance.

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on January 19, 2018, 02:01:35 PM
The paper is stiffened very effectively by creating ribs in it.
That's a good idea. You could use it for the sides of - say - a Sopwith Triplane.
The Stosser was possibly the best-flying indoor model I ever saw but the technique is not suited  to compound curves. He used airmail paper for the smaller models like the Fokker DVIII. At the other extreme, the first time I met Mike (outside the Nottingham club tent/bar at the nationals) he was wielding a biggish Mitsubishi Claude.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 19, 2018, 06:50:38 PM
Not sure what you are saying Bill  ???  Well I do actually!  In all honesty I didn't see his model until after I had published the Triplane plan to VMC... ;D

What can I say - great minds think alike?  :D

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Gromit on January 22, 2018, 01:14:00 PM
Mike had championed the paper stressed skin structure from the very early days - before my time I will add to forestall the expected comment!  His first published paper skin design was a Ryan PT25 in the January 1946 Aeromodeller when he was 19 and a draftsman at a Doncaster boiler manufacturer if I remember correctly.  The model was a round-the pole model of around 18" span although he said that he had been experimenting with FF models for a couple of years before that.  I've not located the original Interceptor publication (Paul's model) as yet.

His technique involve pre-coating papers of differing weights, dependent on the size of model of course, with a couple of coats of thinned dope (or sometimes banana oil depending how stiff he wanted the resulting parts - Banana oil being a bit more flexible) on both sides to maintain a flat sheet.  He sometimes painted/sprayed the final finish on one side before building and would project the 3D shape directly on to the back of the prepared paper before cutting and assembling - all very skillful with that skill now being lost with the advent of CAD.

I've tried this technique a few times and it is not easy particularly where the prototype has a bit of double curvature so well done Paul

Doug


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 22, 2018, 02:38:46 PM
Is that the NMAC Doug?  ;D

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Work In Progress on January 23, 2018, 09:52:37 AM
Whichever Doug it is, it's a most interesting inaugural post, so hello!


Title: Re: VMC Cessna Bird Dog
Post by: Hepcat on January 23, 2018, 08:56:00 PM
I always remember Mike Heatherington's 'Ryan' because the Jan 1946 'Aeromodeller' also had the 'Hepcat' plan and I was also 19 and also was an apprentice draughtsman but I was serving my time at 'Aveling-Barford', makers of Road Rollers.  At that time Barfords were making what was probably the last Steam roller. It was for export to India where there was lots of free stuff to burn to keep the steam up.
John


Title: Re: VMC Cessna Bird Dog
Post by: Pete Fardell on January 24, 2018, 03:29:58 AM
Fascinating! And 'Barfords steam rollers' will now need googling. You never know what you're going to find out on this forum. Thanks John!


Title: Re: VMC Cessna Bird Dog
Post by: Ausmodeller on January 24, 2018, 06:14:55 AM
I don't know about anybody else but when I pass road works I still refer to road rollers as 'steam rollers'.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 24, 2018, 03:58:49 PM
My lad who is nine calls it a steam roller!  I think the name has stuck, even though steam has nowt to do with it, and hasn't for quite some time...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: ZK-AUD on January 24, 2018, 05:55:06 PM
It was for export to India where there was lots of free stuff to burn to keep the steam up.
John

  I think they burn dried cow turds over there,  but that may be for cooking on.  Steam rollers might need a greater calorific value


Title: Re: VMC Cessna Bird Dog
Post by: Pete Fardell on January 24, 2018, 05:57:55 PM
I think it probably IS called a steam roller still. Does anyone say 'road roller'? I suppose a lot of current words have obsolete origins. (Eg. 'Pen' really means feather, but even up here in darkest Yorkshire few of us still write with quills.)


Title: Re: VMC Cessna Bird Dog
Post by: DHnut on January 24, 2018, 06:11:56 PM
I can remember steam rollers of the Avelling Barford type in Auckland. Road repair was a somewhat slower process in those days. I think coal was used as the fuel and the spectacle and noise was impressive. Start up was a leisurely processif from cold.
Clearly John you gravitated up the road to DH and greater things.
  Ricky


Title: Re: VMC Cessna Bird Dog
Post by: Gromit on January 25, 2018, 10:43:16 AM
Yes Andrew, NMAC Doug

I think usual is steam roller for coal-fired with solid roll at the front, road roller for diesel power with roll, steam tractor for coal-fired with wheels and Showman's engine for a tractor with big generator and fairground lights. Learnt to drive them with a pal many years ago who now has 12.5 ton Aveling and Porter steamroller from 1920 called Sarah.

Wing loading far too high so I reverted to aeromodelling

NMAC Doug



Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on January 25, 2018, 12:58:12 PM
Great to see you on here Doug!

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Nigel Monk on January 25, 2018, 05:38:10 PM
I thought you'd keep schtum (sp?) and be Cheshire cat Doug  ;D (can't do a grin-only emoticon)

You've started now...


Title: Re: VMC Cessna Bird Dog
Post by: Hepcat on January 26, 2018, 06:55:41 AM
Here is another interesting thing about road rollers (sorry, skip the 'another'). One day I saw a casting,  about the size of a coffin being unloaded and I asked what it was for.  I was told it was literally a ton weight.  It was mounted under the body of the roller and could be winched forwards and backwards to get the CG in the correct place bwtween the forward roller and the rear wheels. So, when an expert tells you to put a bit of clay in the nose to get the balance right, take notice, it is good engineeringpractice.
John
 


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on February 13, 2018, 06:33:01 PM
Rollering on...

After much searching and trials by the guys at VMC they finally managed to get some suitable dark green tissue.

Here it is as a trial on my rough cut mock up...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Work In Progress on February 14, 2018, 07:56:33 AM
Excellent. I like the look of that colour and density for all sorts of subjects.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on February 14, 2018, 08:40:04 AM
The colour density is good, although slightly variable...

Certainly decent enough for a coloured tissue model, and a decent base for a light dusting of paint for those so inclined...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on March 07, 2018, 04:38:15 AM
Here is the final prototype for the kit pictures.

The tissue looks really good, well worth the effort and delay of trying to find a suitable colour.

I'm guessing this will be available in 4-6 weeks or so...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on March 07, 2018, 05:01:08 AM
It looks a cracker Andrew. Do I see double curvature on the rear screen? And is it easy to fit the front? My technique is to ensure there is balsa dust inside that can appear later inside the screen, then smear lots of glue where it shouldn't  be. Of all the skills I don't have, fitting screens neatly is the one I don't have the most.


Title: Re: VMC Cessna Bird Dog
Post by: FreeFlightModeller on March 07, 2018, 05:14:58 AM
Hands up all the WW1 builders that have the same problem!

Nice build Andrew  :)


Title: Re: VMC Cessna Bird Dog
Post by: Pete Fardell on March 07, 2018, 09:17:09 AM
Very nice indeed! And I agree- the tissue looks spot on.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on March 07, 2018, 10:08:26 AM
Hi,

Thanks All.

Bill the rear screen is scored in a triangular shape to make a flat centre part and then curved sides.  The front should meet fine if the shape is cut accurately.  The Acetate that VMC provide is just the right thickness, not too thick to be heavy and not too thin to make it easily damaged.  Because it is suitably thin it is easily held in position temporarily with small tabs of masking tape without it "pinging" out.  So generally I get it all in position dry using making tape, then feed tiny amounts of superglue in at the free edges at key points using a pin allowing it to capillary into the gap.  Because I use so little it doesn't "fog" and if you hold the acetate down with the point of a pin until the glue goes off you don't end up with you or something else being glued to the model, or indeed finger prints on your windows...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: cvasecuk on March 07, 2018, 10:15:37 AM
That does look very nice. If VMC get them out soon I would not be surprised to see one entered in KS at FF Nats.
Ron


Title: Re: VMC Cessna Bird Dog
Post by: ZK-AUD on March 07, 2018, 12:01:20 PM
Andrew's tape technique but with thinned RC56 is my preference.  It actually draws itself in to the edge and dries clear in any case so glue smears are unlikely


Title: Re: VMC Cessna Bird Dog
Post by: OZPAF on March 08, 2018, 07:49:13 PM
Another impressive effort Andrew. A simple choice but so well done.

John


Title: Re: VMC Cessna Bird Dog
Post by: Monz on April 22, 2018, 01:06:09 PM
And here's Dad flying his version.


https://www.youtube.com/watch?v=5rSnH-cr_3U (https://www.youtube.com/watch?v=5rSnH-cr_3U)

https://www.youtube.com/watch?v=4PutuuN1s18 (https://www.youtube.com/watch?v=4PutuuN1s18)


Title: Re: VMC Cessna Bird Dog
Post by: Kman on April 27, 2018, 08:28:20 AM
Hi Andrew,

I have just seen the Bird Dog on VMC website, it is down as 18” wingspan, is this correct?

Klaus


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on April 27, 2018, 11:24:56 AM
Hi Klaus,

No, that is incorrect, it is 21" (535mm)

I will ask them to correct it, thanks for pointing it out...

Andrew


Title: Re: VMC Cessna Bird Dog
Post by: TheLurker on May 25, 2018, 04:23:12 AM
Ordered.

As was some light grey tissue. The plan is to finish it off as a USAF O1.  Possibly a shark-mouth O1-E.  Not a scheme I'd have considered but for Pete F's shark-mouth A9.  See the attachment. And if the shark-mouth doesn't work out there are plenty of POG USAF O1-{x} variants to pick from.

Something to look forward to building come autumn / winter.


Title: Re: VMC Cessna Bird Dog
Post by: Newbie_John on March 21, 2019, 06:27:34 PM
Just thought I'd "bump" this topic by saying I've just flown my first FF indoor model, and it was the VMC Bird Dog!
So big thanks to Andrew for a kit that a beginner to these models was able to put together without too much difficulty, and flew first time!

I took it to Berinsford, where Ian Melville & co were suitably encouraging about my construction attempts (my stubby little fingers need a lot more practice :D), and they guided me through it's first trimming flights, introducing me to downthrust and motor widths along the way ;D What a great, friendly bunch of guys!

At the end of my session, it was actually circling the hall (briefly - I've got to learn to add lightness next ;) ;) - flying weight is 36g at the moment >:( )

My wife can't quite believe that I've actually managed to fly a model that's come home in one piece - it's obviously been the radio bit that was the problem with my others!!

Please bear with me as I add a proud video of my first success at indoor flying ( and you can tell by Management's voice that she was impressed/ astonished too ;D ;D ;D

https://youtu.be/oCWOzifCPJo

A very chuffed John


Title: Re: VMC Cessna Bird Dog
Post by: OZPAF on March 21, 2019, 07:57:48 PM
Good on you John. An enthusiastic response like that will make Andrew's day I would guess.

John


Title: Re: VMC Cessna Bird Dog
Post by: Jack Plane on March 22, 2019, 04:36:24 AM
Ta-Da!!

Well done!  Next challenge... ROG  ;D


Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on March 22, 2019, 05:03:50 AM
Yes, well done. That looks a very small hall - it will go even better given more room to roam.


Title: Re: VMC Cessna Bird Dog
Post by: TheLurker on March 22, 2019, 09:08:13 AM
It's enormously satisfying (and not a little addictive) when they do fly isn't it?  :)

Nice one.
Lurk.


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on March 22, 2019, 04:40:02 PM
Nice flight Newbie John, you should be justifiably proud.  36g isn’t all that bad, as there is lots of (relatively heavy) glazing, but there is plenty of wing area to the Dawg to keep it aloft.

In a bigger hall you can open up that turn which will gain you more altitude, thus you should be able to fit a slightly longer motor and be in very very good good form...

Congrats, and yes it made my day!  ;D

Andrew



Title: Re: VMC Cessna Bird Dog
Post by: Newbie_John on March 22, 2019, 07:08:27 PM
Thanks everybody for the kind words and encouragement - much appreciated!
I think I'm hooked ;D ;D ;D

And amazingly it did ROG for 1 circuit, Jack Plane, but SWMBO didn't have the video going! ::)

Andrew - thanks for the tact about my AUW , but I've got a lot to learn yet about how to get it down to your 26g or so !

Cheers, John


Title: Re: VMC Cessna Bird Dog
Post by: Andrew Darby on March 22, 2019, 07:24:34 PM
Hey John glad you are hooked- Just have fun!  ;D ;D



Title: Re: VMC Cessna Bird Dog
Post by: billdennis747 on March 23, 2019, 02:47:03 AM
Andrew - thanks for the tact about my AUW , but I've got a lot to learn yet about how to get it down to your 26g or so !
It's easy John:
1. Use lighter wood than you think you need
2. Keep the back end especially light so you need less noseweight
After 50 years I'm nearly there. Another 20 should do it.


Title: Re: VMC Cessna Bird Dog
Post by: Jack Plane on March 23, 2019, 03:05:03 AM
Also use less glue.  Don't actually starve the joints but one generally needs far less glue than one thinks.  (I use Aliphatic as its faster drying and easier to sand than PVA.)  Also don't lather on too much dope.  For indoor flying, one coat of non-shrinking dope thinned 50/50 will do.

Jon


Title: Re: VMC Cessna Bird Dog
Post by: SP250 on March 23, 2019, 06:29:32 AM
Welcome along John

Now that makes 3x current or ex Daimler SP250 owners who are also into aeromodelling (Alan Fry being the other).
As you have found already, this bunch are just as friendly and helpful as the Daimler club.
I look forward to seeing you at the indoor nats in a month's time for a catch up.

John M



Title: Re: VMC Cessna Bird Dog
Post by: abl on March 23, 2019, 11:13:16 AM
Nicely done, John.

Andrew - thanks for the tact about my AUW , but I've got a lot to learn yet about how to get it down to your 26g or so !
It's easy John:
1. Use lighter wood than you think you need
2. Keep the back end especially light so you need less noseweight
After 50 years I'm nearly there. Another 20 should do it.

What he said...  :)

Andy


Title: Re: VMC Cessna Bird Dog
Post by: ZK-AUD on March 23, 2019, 11:52:05 AM





It's easy John:
1. Use lighter wood than you think you need
2. Keep the back end especially light so you need less noseweight
After 50 years I'm nearly there. Another 20 should do it.
[/quote]

And my personal favourites:
3. Be enthusiastic with your sanding block
4. Use thinner wire than supplied
5.  Scrape your plastic props down to about 60% of their original weight


Title: Re: VMC Cessna Bird Dog
Post by: ZK-AUD on March 23, 2019, 11:55:57 AM
Oh, and congratulations on your success!!  For a bonus point see if you can get SWMBO to build one now.


Title: Re: VMC Cessna Bird Dog
Post by: Newbie_John on March 24, 2019, 01:35:09 PM
Many thanks to all for the advice and kind comments.

I measured my nose weight, which I'd put in the undercowl exhaust area rather than the actual nose, to discover I'd had to add 4.5g to achieve balance. Since the tail moment is 4:1 from there, if I'd just saved 1g or so on the tail area, I now realise I'd have dropped my flying weight by 4g or so. Old hat to you folks, but I'm now beginning to understand the comments about wood weight and excess glue much more ;)

To help me progress, I've bought the BMFA Gymminie Cricket and Frog to give my stubby little fingers practice in handling light small section wood, and a pipette-type dispenser for my glue bottle  ;D

And ZK-AUD, no chance I'm going to let SWMBO show me up on this stuff!!

Cheers, John


Title: Re: VMC Cessna Bird Dog
Post by: Ian Melville on March 26, 2019, 07:29:55 AM
Hi John, great to meet you at the OFMAC events. The dog is going well and awakened my passion for the type.

Nice that SWMBO is willing to take control of the rubber winding, while you act as stooge.  :) cue fettish  jokes!

Hope you can make the indoor nationals, a great day for networking and inspiration.


Title: Re: VMC Cessna Bird Dog
Post by: Newbie_John on March 26, 2019, 11:07:17 AM
Thanks, Ian!

Yes, SWMBO and I are booked in to come & spectate at Walsall, where I'm hoping to get her  certificated as "Winder-in-Chief"- or should that be Certified  :D :D :D