Logo
Builders' Plan Gallery  |  Hip Pocket Web Site  |  Contact Forum Admin  |  Contact Global Moderator
January 25, 2020, 05:53:24 AM *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with email, password and session length
 
Home Help Search Login Register
Pages: [1] 2 3   Go Down
Print
Author Topic: Megow's Blackburn Skua  (Read 2771 times)
0 Members and 1 Guest are viewing this topic.
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« on: November 06, 2013, 06:44:28 AM »

I haven't seen this model on this forum although someone made a comment about it some time ago.

I downloaded the plan from the excellent Builders Plan Gallery for something to do.  It looked as though it would be quite light with good wood
and I have always liked the shape of this early WW2 aircraft and it's sibling Blackburn Roc. If it gets finished I would like to see it in the Target tug colour scheme - looks good but complicated so it may be a simpler finish. But to get to that state I have to start it.

The plan says it is a 15" flying scale model, kit number F55. The drawing is quite complete with the fuselage formers finely drawn. There are minimal instructions
for building in minute typewritten script.  It looks as though it was drawn 2x or 4x full size and then photographically reduced. Some items are dimensioned but others can only be guessed at without a kit.  I assume that printed sheet balsa was supplied but with all the full size parts shown on the plan it may have been up to the builder to draw and cut the parts. Someone will know. As the formers and ribs look to be drawn thinner than the 1/16th dimensions I have assumed them to be 1/20th. As I don't have 1/20th I have used some thick 1/32nd sheet.

The fuselage is just a 1/16th square box structure with the formers glued to the cross members. To this structure is added 1/16th x 1/32nd stringers on edge to give an approximation of the real full size fuselage shape.  I will have to wait till it is covered to see how effective this will be. So let's start.
Attached files Thumbnail(s):
Megow's Blackburn Skua
Megow's Blackburn Skua
Megow's Blackburn Skua
Megow's Blackburn Skua
Logged
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #1 on: November 07, 2013, 10:54:49 AM »

It rained all day yesterday so I got a bit more done to the fuselage.  This is a bit smaller than my usual builds and is quite fiddly, but keep going.
Attached files Thumbnail(s):
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Logged
Mark Braunlich
Platinum Member
******

Kudos: 77
Offline Offline

United States United States

Posts: 1,044




Ignore
« Reply #2 on: November 07, 2013, 12:38:35 PM »

Spadge
Megow had several models designed for 30" span and then issued in both 15" and 30".  I have original kits of their Republic AT-12 in both sizes. They also shrunk several of the pre-WW2 30" kits to 24" in the post war years and kept the same kit number just to make it interesting  
Logged

Mark
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #3 on: November 07, 2013, 02:28:18 PM »

Mark,    thanks for information.  So, it could have been drawn to 30" and then reduced as I suspected which explains the small type size.  Did they supply printed sheets for formers and ribs or just sheets of balsa?
Logged
Mark Braunlich
Platinum Member
******

Kudos: 77
Offline Offline

United States United States

Posts: 1,044




Ignore
« Reply #4 on: November 07, 2013, 03:59:47 PM »

Megow had proper printwood Spadge.
Logged

Mark
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #5 on: November 10, 2013, 02:42:00 PM »


In between visits to the supermarket, cutting the lawn for the last time (again) this year, repair the economy dual flush cistern and the usual things that get in the way I have done quite a bit of work.  There again it is pretty small so it should build quickly.

A modification to the original was to replace the rear rubber hook with a more modern aluminium tube set up.  I have kept the position of this tube in the same location as the original hook.

The Skua had a long cockpit canopy and the kit instructions make no mention of this part.  So, was it a vac forming or was it intended to be made up from flat acetate sheet? There are two tiny formers shown on the drawing for the canopy structure that are necessary if it is to be made from flat acetate but how was the front and rear of the canopy to be made if not a vac forming? I decided that I would make a plug and vacuum form a canopy that incorporates the curves as drawn. I made a rough plug for vac forming and pulled off a rough moulding just to see how it would fit. Now I have a better idea about the fit the plug has been improved for the final canopy.


The engine cowling is shown on the drawing with the panels made from card and a fixed "balsa turned nose" fitted with a hardwood thrust button.  I thought it better to make the cowling front end as a ring and mount the dummy crankcase front separately so that the prop assembly can be removed for winding and allow that part to be shimmed for trimming. This should leave the nose ring nicely glued to the front of the card cowling.  I have used card cowlings before but they usually end up with little dents and unintended shapes when covered with tissue or doped and painted. To try for a nice smooth cowling I cut a shape from card and trimmed it to fit. I then used this template to cut a piece of 120g printer paper to shape along with another over-sized piece.  These were doped a couple of times on both sides with very thin clear dope and allowed to dry. Then, after coating each with thinned contact adhesive and allowed to flash off they were laminated around a suitable sized aerosol can and the adhesive reactivated and sealed with a hot iron.  This made a nice rigid shape similar to the  rolled metal original.  This cowling will be fixed to the structure after the fuselage is covered and the nose ring glued onto the front bulkhead to give a nice (hopefully) smooth front end that won't need to be packed out for trimming.

Although the drawing is very neat there is one glaring error.  Bad day at the drawing board or "let the kid do the simple bits".  This part is the stabilizer.  Today with CAD just draw one half and copy and flip to make identical halves.  Look at the photos.  A simple redraw makes it look nicer to me.

The wings have 1/16th square top and bottom spars with 1/16th x 3/32nd LE and TE.  The LE is angled to give a nice front shape that should cover well.  The TE has slight angle easily planed to shape.  I used 1/16th tips to match the TE thickness.

The rib shapes are drawn stacked with no indication whether there should be a root rib size piece stuck to the fuselage to aid fixing the wings.  The top view shows two lines where wing meets fuselage so I have added them anyway.

The wings went together easily.  There is plenty of dihedral, perhaps too much.

As the collection of sub assemblies increase, temptation takes over and I just have to start to put bits together.  It still doesn't look too much like a Skua but time will tell.
Attached files Thumbnail(s):
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Logged
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #6 on: November 21, 2013, 03:50:43 PM »

Managed to do a few more things in between various other essentials necessary for life.

I made a plug for the canopy to fit in the appropriate space then pulled a canopy on the vacuum bed.  The front of the cockpit is nearly vertical and I may try another pull with the front of the plug a bit higher than the rear to give a bit of draw. 

I have looked at various websites for more information about the Skua and realise that the information available to Megows would have been a bit sketchy at the time so it is more approximate scale rather than true scale.  However, the idea was to build a model from the kit plan so accuracy to full-size doesn't matter all that much to me.

Wheels next.  I have a liking for the old turned hardwood wheels that most probably would have been used in the kit.  I realize that a bit of foam trapped between a couple of pieces of half mil ply would be lighter but I decided to go for the traditional look. I had previously rescued a cricket wicket from the scrap bin at our local cricket club field where I fly my R/C models.  It had been broken, probably by a fast bowler,  unfortunately not Stuart Broad (Oz members will appreciate that - I don't think  Grin).  It was just the correct diameter for the wheels and I believe made of Ash, perfect for wood turning.  I settled on 5mm thickness for the wheels and made a profile tool from 2mm steel, just to see if it would work.  I started by drilling a 5mm dia hole in the steel then hacksawed and filed the piece to leave half a hole and the taper to the centre of the hub.  I filed the underside at an angle to give a sharp edge. 

Gripping the wood in the lathe chuck I mounted my new profile tool at just below centre height and selecting a fairly high spindle speed fed the tool into the wood until it had cut all the way along the profile.  Next, I drilled a suitable size hole for the axle.  Then the tool was turned through 90 degrees and the same tool cut the rest of the wheel's tyre shape and started the cutting point for parting off.  All that was needed was to part off and repeat the process for the other wheel. A very basic job that could have been similar to the method used in the 40's. The tool left a nicely polished surface on the face with the slightly rough back that I remember from years ago.  Very satisfying. 

Covering comes next.  I have made a start so will have to keep at it now.

I had hoped to have the model ready for this Saturday at the Manchester Velodrome but shopping, gardening (picking up leaves), walking up to the top of Kinder Scout (a big hill, not quite a mountain but it makes me puff a bit) and a few other jobs means that it may possibly be ready but unfinished and untrimmed.  Nothing new there.     
Attached files Thumbnail(s):
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Logged
Balsa Ace
Gold Member
*****

Kudos: 25
Offline Offline

Canada Canada

Posts: 466


FAC Member



Ignore
« Reply #7 on: November 22, 2013, 05:28:45 AM »

Great Fleet Air Arm aircraft build,Spadge.

Scott
Logged

Hawker Sea Fury FB.11
HMCS Magnificent
VF-871   Royal Canadian Navy
DavidJP
Titanium Member
*******

Kudos: 47
Offline Offline

United Kingdom United Kingdom

Posts: 2,919




Ignore
« Reply #8 on: November 22, 2013, 06:03:44 AM »

Hmmmm... clever stuff !!

What did you use for the cowling? Interested because in the past I have used paper and thin plasti card. I recently acquired some Tyvek paper which is used among other things apparently for making envelopes that need to be strong. It is 'woven". It seems very flexible and can't be torn easily. I am told it is good for cowlings and fairings etc. have you used it?
Logged
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #9 on: November 22, 2013, 12:29:57 PM »

What did you use for the cowling? Interested because in the past I have used paper and thin plasti card. I recently acquired some Tyvek paper which is used among other things apparently for making envelopes that need to be strong. It is 'woven". It seems very flexible and can't be torn easily. I am told it is good for cowlings and fairings etc. have you used it?

I remember having stuff in tyvek envelopes in my previous life.  I kept some but haven't seen them for years. I thought they would be useful but never used them.

The cowling method I have used on this build is described in reply#5 above.  Just 2 layers of 120g printer paper rolled around a suitable mandrel when sticking the parts together.  When I made it I thought that if I was going to a fancy dress party I could make a very serviceable vicar's collar using this technique.  More tea Vicar? Smiley
Logged
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #10 on: November 22, 2013, 02:30:15 PM »

Scot,  the Skua is not a well known aircraft even in the UK.  I don't think there are any left.  It is one of the few WW2 US and UK aircraft I didn't see.

Logged
Balsa Ace
Gold Member
*****

Kudos: 25
Offline Offline

Canada Canada

Posts: 466


FAC Member



Ignore
« Reply #11 on: November 23, 2013, 08:05:59 AM »

Scot,  the Skua is not a well known aircraft even in the UK.  I don't think there are any left.  It is one of the few WW2 US and UK aircraft I didn't see.


It's sad when there are no surviving WW2-era aircraft like the Skua around anymore.
Logged

Hawker Sea Fury FB.11
HMCS Magnificent
VF-871   Royal Canadian Navy
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #12 on: November 30, 2013, 03:02:59 PM »

I went to the Velodrome and had my first taste of indoor flying.  Very enjoyable.  As expected the Skua was not finished but I flew my Guillows Bird Dog (pictures in here somewhere).  I had made a new noseblock for it with smaller plastic propeller and as the day wore on I found a reasonable sized motor and number of turns and eventually got it to fly a few circuits.

Back to the Skua.  So, all I had to do was to cover it and join the bits together.  Tissue or silver mylar ... decisions, decisions. I have to confess that I prefer opaque covering rather than the see-through tissue type (artistic as it maybe) so silver mylar won. I looked on the net for simple colour schemes and as the design is not really true to scale the paintwork is only roughly correct but looks better than no paintwork.

I have just glued the first wing to the fuselage and printed off some roundels.  When fully assembled it will get a very light spray of thinned gloss enamel on the top surfaces to take off the dull matt finish. A rethink of the wheels, so lovingly replicated, is necessary.  They weigh nearly 2 grams (over 12% of the total weight so far) so they will have to be replaced with wheels made from foam.
Attached files Thumbnail(s):
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Logged
Pete Fardell
Palladium Member
********

Kudos: 123
Offline Offline

United Kingdom United Kingdom

Posts: 5,091




Ignore
« Reply #13 on: November 30, 2013, 03:41:41 PM »

I do like that Mylar finish. Your Lysander looked very good in it too. Is it hard to apply, compared to tissue?
Logged
Prosper
Platinum Member
******

Kudos: 56
Offline Offline

United Kingdom United Kingdom

Posts: 1,458



Ignore
« Reply #14 on: December 01, 2013, 03:21:34 AM »

Pete, it doesn't seem to be, at least for Spadge! He kindly shared this explanation of his method when the topic came up before, and some other advocates add their experience too.

http://www.hippocketaeronautics.com/hpa_forum/index.php/topic,11682.0.html

I tried this and couldn't get along with it - but then I can't cover with tissue very well either . . . IIRC I just couldn't get the seams and overlaps tidy, whereas by using massage and dope/thinners, tissue seams and overlaps kind of melt into themselves. 

Stephen.
Logged
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #15 on: December 01, 2013, 05:54:50 AM »

I do like that Mylar finish. Your Lysander looked very good in it too. Is it hard to apply, compared to tissue?

There is a learning curve just like learning to apply tissue without creases and without warping light structures.  The most important parts are to get the iron temperatures right and getting the "grain" in the right direction as mylar shrinks differently along the length of the roll than across the width.  If you cut the wing covering from along the length of the roll then there will be less droop between the ribs than if you cut the covering across the roll. Fuselages need to be covered with the length across the roll in my experience.

As to temperature of the iron - I suppose they all vary so you have to get used to your appliance.  I do the first tacks to the frame with a lower temperature than used for shrinking.  The shrinking part is the most dangerous as the heat can cause the mylar to suddenly disappear if the iron is too hot.  Silver mylar cannot stand the same heat as clear mylar.

The only way is to try it. Grin
Logged
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #16 on: December 01, 2013, 06:10:19 AM »

Pete, it doesn't seem to be, at least for Spadge! He kindly shared this explanation of his method when the topic came up before, and some other advocates add their experience too. http://www.hippocketaeronautics.com/hpa_forum/index.php/topic,11682.0.html
I tried this and couldn't get along with it - but then I can't cover with tissue very well either . . . IIRC I just couldn't get the seams and overlaps tidy, whereas by using massage and dope/thinners, tissue seams and overlaps kind of melt into themselves. 
Stephen.

Thanks for posting the link.  I couldn't find it!

Seams for wings and tailplanes, fins, etc., are overlapped on the LE and TE and trimmed with a sharp razor blade after sealing all way round the item being covered one side at a time.  It is possible to squeeze out the inevitable creases by carefully using the nose of the iron.  It seems better to let the item being covered rest between shrinking phases rather than trying to do it all in one go.  While resting, flying surfaces can be weighed down as it helps to keep them flat.  Weigh them down overnight when completed and the covering seems to go into a stable state and they hold the shape you want, including washouts.

Always pierce the ribs and any enclosed cell to let the trapped air to vent to atmosphere.

It must be easier than moulded all-sheet models although I am thinking about an alternative moulded method.  Just thinking at the moment. Lips sealed
Logged
Pete Fardell
Palladium Member
********

Kudos: 123
Offline Offline

United Kingdom United Kingdom

Posts: 5,091




Ignore
« Reply #17 on: December 01, 2013, 09:17:52 AM »

Thank you. Sounds quite tricky but I shall give it a try some day. It certainly gives a lovely metallic sheen. I might use it on a model which just needs a metallic forward fus or something first and see how I get ion.
Logged
Prosper
Platinum Member
******

Kudos: 56
Offline Offline

United Kingdom United Kingdom

Posts: 1,458



Ignore
« Reply #18 on: December 04, 2013, 04:19:49 AM »

. . . an alternative moulded method.

Well, we're told that there's more than one way to skin a cat, but irritatingly we're not provided with even a rough estimate of how many ways there might be Cheesy. I'm sure I've only touched on one of many methods that could work, so I hope you delve into the matter, and I won't be the only one who's keen to hear about it if you go anywhere with this. Don't let it get in the way of finishing off this nice Skua though. It's good to see these 'also-ran' WWII types remembered; I've a big soft spot for Whitleys, Fulmars, Masters, Albermarles etc etc, all these a/c did their stuff.

Stephen.
Logged
Balsa Ace
Gold Member
*****

Kudos: 25
Offline Offline

Canada Canada

Posts: 466


FAC Member



Ignore
« Reply #19 on: December 04, 2013, 07:26:45 AM »

Your Skua is looking mighty good with that covering
and camo applied,Spadge.

Scott
Logged

Hawker Sea Fury FB.11
HMCS Magnificent
VF-871   Royal Canadian Navy
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #20 on: December 04, 2013, 03:58:12 PM »

Thanks for the encouragements. 

I have glued the second wing to the fuselage then the tailplane and fin.  Printed off some roundels that looked about the correct size and fitted them.  I used a Lazertran white water-slide decal paper that prints okay on an Epson printer but there does not seem to be enough adhesive and as they dry they start to peel off.  I have had this problem before and brush on some clear acrylic varnish on the back before sticking them on the model.  Are there any better papers out there?

I have had a rethink on the wheels and have decided to make them a bit like those on the Guillows Bird Dog.  Foam tyres cut from an old mouse mat 22mm dia with an 8mm hole cut using my telescopic aerial hole cutter, then a 1/16" balsa core the same size as the hole in the tyre. 12mm outers cut from 0.5mm ply go each side.  The balsa core is glued to one ply outer then the plan is to compress them while glueing the bits together.  To enable the foam to be compressed while glueing I turned up a couple of nylon pieces to be threaded on to a pin and onto the wheel parts and put under pressure to grip the tyre while the glue cures.  That's the plan.

The next operation will be to attach the undercarriage legs to the wing.  Unfortunately Mr Megow (Was there a Mr Megow or is there a town somewhere in the US called Megow?  Information on Megows and the people involved would be appreciated) had another bad day at the drawing board when it came to fixing the undercarriage gear to the wings.  There is a crude sketch showing the top of the gear leg just glued to the underside of the second rib with a thin strut going from the leg to the same rib.  Even a gentle sideswipe would cause the leg to come off.  The front view shows a thin strut going from the leg to the wing/fuselage joint.  I included additional structures to take the legs when I built the wings and will put on a couple of struts as on the fullsize.  That should keep it together - unless it hits a table leg or dives in at some indoor venue.

After the above all I have to do is make the prop assembly, a bit of cosmetic work and try and get the thing to fly.

Attached files Thumbnail(s):
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Re: Megow's Blackburn Skua
Logged
DavidJP
Titanium Member
*******

Kudos: 47
Offline Offline

United Kingdom United Kingdom

Posts: 2,919




Ignore
« Reply #21 on: December 04, 2013, 04:23:42 PM »

I used paper fro Mr Decal - and so far it has stayed put!

I am in admiration of the "paintwork". Sorry if you have already described how you did this but may I ask please - I am mindful the Hurricane I am doing (FF power job by Eric Fearnley) will need a camo. finish but I am anxious to keep the weight down. It will be tissue covered and I intend to use the minimum by way of dope/banana oil and then spray acrylic colours.  There is always the difficulty of keeping the spray as dry as possible.  Any tips please?

Many thanks
Logged
RalphS
Gold Member
*****

Kudos: 24
Offline Offline

United Kingdom United Kingdom

Posts: 829

Topic starter


Ignore
« Reply #22 on: December 04, 2013, 05:08:43 PM »

I used paper fro Mr Decal - and so far it has stayed put!

I am in admiration of the "paintwork". Sorry if you have already described how you did this but may I ask please - I am mindful the Hurricane I am doing (FF power job by Eric Fearnley) will need a camo. finish but I am anxious to keep the weight down. It will be tissue covered and I intend to use the minimum by way of dope/banana oil and then spray acrylic colours.  There is always the difficulty of keeping the spray as dry as possible.  Any tips please?

Many thanks

Thanks for Mr Decal tip.  I will look it up.

Regarding the Hurricane or just about any freeflight model larger than about 20".  I would use Esaki tissue over clear mylar (both from FreeFlight Supplies (Mike Woodhouse.)  Most people agree that this is lighter than doped tissue alone.  As for spraying acrylic.  Don't thin it too much. Just thin it until it sprays.  Have a bowl of water handy to keep the paint from drying on the nozzle.  Practice on the inside of cereal boxes.
Don't get too close.  Build up the paint with a first dust coat, then one or two further light coats.  Practice.  Practice.
Logged
skyraider
Platinum Member
******

Kudos: 93
Offline Offline

United States United States

Posts: 1,300

WWW

Ignore
« Reply #23 on: December 04, 2013, 05:50:58 PM »

Quote
(Was there a Mr Megow or is there a town somewhere in the US called Megow?  Information on Megows and the people involved would be appreciated)

Yes there was. Fred Watrous Megow (pronounced MAY-GO). In 1929, he taught shop and Mechanical drawing. His designs included flying and solid display models. Some of these early types can be bought from http://www.pennvalleyhobbycenter.com/ Megow built his empire of flying and display models over a space of 12 years. In 1948, he called it quits and began liquidating everything associated to modeling. By 1949, the Megow Corporation ceased to exist.& Fred W. Megow passed away March 12, 1977 due to complications resulting from a stroke.

Skyraider
Logged
DavidJP
Titanium Member
*******

Kudos: 47
Offline Offline

United Kingdom United Kingdom

Posts: 2,919




Ignore
« Reply #24 on: December 05, 2013, 04:48:57 AM »

Many thanks Spadge, so it looks as though I will have to pay another visit to the Woodhouse emporium as I find I have no clear mylar! I am not sure if it is an advantage or not living not far from him. He always seems to have something I have not seen before and end up buying.

And thanks for the spraying tips - have sometimes managed a nice dry coat at first go - then on another occasion not so good! As you say it is practice and "familiarity" until it becomes instinctive!
Logged
Pages: [1] 2 3   Go Up
Print
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!