Avro Arrow - a correct version of the Hobbycraft 1/72 kit - I hope!

[John R]

After building a 1/72 scale Hobbycraft CF 105 Arrow and discovering at the end that the decals were not too good I posted a question on Britmodeller asking if anybody made a decent set. This opened a ‘can of worms’ as the discussion shifted to the kit itself and the lack of accuracy thereof. I had corrected what I believed to be the only major error , the actuators being on the topside of the wing instead of the underside, but it turned out that almost nothing about the kit was correct.

What should I do about it? One of my fellow club members suggested that ‘it looks like an Arrow so leave it’ but somehow I couldn’t. As a kind soul in Canada donated an aftermarket set of decals and whilst wondering whether or not to rip apart the Arrow I had just built Chris Tyler said I could have one that he had started but given up on. ‘Navy Bird’ sent a copy of what were alleged to be Avro drawings. Having been given these it seemed impolite not to get started but I told the donors not to hold their breath…I toyed with the idea of doing a WIP thread but was afraid the lack of ‘P’ might invalidate it. Anyway after a year of stop/start it has reached the stage where it looks as if it might be finished.

Using the Boston Mills book, ’Arrow’, and the ‘Avro’ drawings I produced a thread on correcting the errors which has so far collected over 3500 hits so there is a lot of interest out there. It is

http://www.britmodeller.com/forums/index.php?/topic/234918500-correcting-the-hobbycraft-172-cf-105-arrow/

So we start with a pan of ‘Arrow soup’. The parts were warped and the only way I found to cure this was to soak the parts in a pan of hot water to get them thoroughly warm before attempting to straighten them.

Wing. The wing planform is incorrect

Bits were added to give the correct sweep of the inner panel and the outer panel sweep wass increased. Reshaping of the leading edge was needed to give the drooped LE. Aerofoil section was too thin at mid-chord but it was decided to live with it. The wing, when attached to the widened fuselage, gave the correct span so no correction was needed.

Fuselage. The fuselage is too narrow and too short. There are strange ‘area rule?’ bulges aft of the intakes which need to be removed. ( How did Hobbycraft get that wrong?)

The fuselage was widened by inserting spacers. The lower gap was filled with a strip of sheet. The upper gap was covered by the wings and spine so was left open.

The intakes were widened by inserting spacers. They were also reshaped to make them less rectangular. They were then glued to the front fuselage after fitting new boundary layer bleed panels. (no picture - sorry). The front fuselage width was about right so it was unmodified but the nose shape required some correction (more of this later)

The section between the nose and the rear fuselage was built from scratch. The back end was built from scratch. This was not easy and should have been done at the same time as the fuselage widening.

The engine nozzles were made by using a Dremel tool as a lathe. A blank was turned out of balsawood. This was planked with plastic strips and roughly turned to shape with sandpaper. It was then coated with Milliput and turned to a final shape. The nozzles were then fitted to the fuselage. It is important to note that the engine thrustline is canted two degrees up. It doesn’t sound much but if you don’t get it right the back end looks completely wrong. Guess how I found this out!

The kit spine was used except for removing the bulges alongside the cockpit and correcting the exhaust outlet

The fin was modified by inserting a section at mid chord and adding a section at the base

The next step was to make a new canopy. I thought that I might get away with reshaping the original but transpired this was not possible as the front windscreen was wrong, not being a straight ‘V’ shape. This caused much grief and I am still not really happy with it.

One detail that caused much difficulty was the shape of the fairings over the transport joints that run chordwise aft of the notches on the wings as I could find no definitive information, only general indications of size and shape. I had sanded down the ones on the kit then realised that I had gone too far and had to make new ones.

One area on contention is the shape of the nose in plan view. The received wisdom was that it is narrower at the cockpit than at the radome. The drawing from the Boston Mills book do not show this but the 'Avro' drawings do although they look as if they have come from the same source. I decided to go with the slight taper as it seems to fit the shape of the radome rather better.

This is where it is at the moment.

I hope this is of interest. Someone commented that it would be like scratchbuilding using the Hobbycraft bits as rough blanks and I would be mad to try…

John

PS. The 'Avro' drawings have a note that they were traced from Avro drawings by a Mr Stroomenbergh so it would be interesting to know their exact provenance

Edited May 24, 2013 by John R

[Scratchbuilder]

How did you get hold of those drawings, John? They look excellent.

Nice accurate work, too.

Martin

[Jessica]

I think I'll just stick with my old Astra Vac kit thanks. It's simpler

[Martian]

Ah! A plane only slightly less cool than the TSR2! Looking forward to seeing how this one turns out.

Martin

[Navy Bird]

That's quite a project, John! Hats off to you for even attempting it. The Arrow is definitely one of the coolest aircraft to emerge from the 1950s.

If you have the kit with the actuators on top of the wing, it's the first tooling. Hobbycraft revised the tooling to fix that error in later editions, but it has now (late 2012) been replaced by completely new tooling which matches the drawings quite nicely. I took the easy way out and bought the newly tooled Arrow!

I provided the drawings to John, but to be honest I can't remember where I got them. They are in 1:24 scale, right John? They have a nice Avro Canada logo on them.

Can't wait for more installments! Which decal sheet from Canada did you get?

Cheers,

Bill

PS. Martin, the Arrow is actually slightly more cool than the TSR2, but that's just my North American providence rearing its head again.

[Tim T]

This has my full attention. I am really looking forward to seeing how this turns out as it is, a Martin says, a very cool aircraft!

[Graeme H]

Forgive my asking, but didn't Hobbycraft correct a lot and reissue this kit?

From memory not everything was fixed, but a lot of the major stuff was.

Could be my dodgy memory though

[Paul J]

Graeme,

Yes they did. Not widely available over here just yet and is pricey. I got one sent from Canada courtesy a BMer. QUite a few corrections to their 2nd issue and better decals. Parts break down different and some better detail but still a couple minor issues.

[John R]

This what appears at the bottom of the 'Avro' drawing. It makes it look like a bootleg version. I think that in those days many manufacturers did not have accurate 3-views. Drawings for the hardware was 'lofted' - laid out full scale on a large flat surface.

[/url

Regarding the latest kit. I learned of its existence when starting out on this project but was horrified by the price but I wonder if it wouldn't have been better to have paid up.

The decal sheet I have was produced by Arrow graphics.

Jessica - did you build the Astra version? It is reckoned to be the most accurate.

John

[Navy Bird]

Graeme,

Yes they did. Not widely available over here just yet and is pricey. I got one sent from Canada courtesy a BMer. QUite a few corrections to their 2nd issue and better decals. Parts break down different and some better detail but still a couple minor issues.

The level of detail (and its scale fidelity) is about the same as the earlier releases. But the size and shape of the new release is much, much better. Very close match to the drawings, with a few niggles, but nothing I would consider major. The sprue layout is completely different.

I compared both the old and new kits side by side on my bench, and every part in the new kit is different (larger, as the first release is a bit under-scale as John points out above, plus there are shape and detail differences). This means the new kit is indeed new tooling, and not a re-work. The new kit is stock no. HC1393 - the old kit is HC1392.

None of this, of course, has anything to do with the utterly fantastic job that John has done with the old kit. Bravo!! A superb display of scale modelling!!

Cheers,

Bill

[Jessica]

Jessica - did you build the Astra version? It is reckoned to be the most accurate.

John

I haven't started it yet; it's still patiently waiting in its plastic bag...

[John R]

One of the problems you get with a long timescale project like this is that you keep noticing things that really ought to be done and would have been a lot easier if they had been done at an appropriate time like providing an u/c bay instead of a door shaped recess and providing some way for the boundary bleed air to escape

I have just noticed that the base of the fin needs cutting back and the rudder needs rescribing. And so it goes on...

John

PS. Bill said 'None of this, of course, has anything to do with the utterly fantastic job that John has done with the old kit. Bravo!! A superb display of scale modelling!!' If you saw the actual hardware you might be less impressed. I always have the feeling that with the amount of effort you expend on something like this you should end up with a gem instead of what looks like a reasonably competently assembled kit.

Edited May 25, 2013 by John R

[DavidWinter]

As someone that has spent a considerable portion of his life nose deep in all things CF-105 Arrow, I have to say I'm very impressed with this build. Being able to wrestle that version of the Hobbycraft kit into something that resembles an Arrow is no small feat. It certainly looks like you've accounted for all the major problems with that version of the kit.

In regards to the other various kits;

- The 1:72 Astra vacu-formed kit is considered to be the most accurate Arrow kit available in any scale.

- The Victoria Products vacu-formed kit is a very close second (they came out around the same time).

- I'd rank the newly released Hobbycraft kit a close third. I did a complete review of that kit over on ARC last year ( http://s362974870.onlinehome.us/forums/air/index.php?showtopic=249877 )

Hobbycraft issued their 1:48 Arrow twice as well. The second boxing is more accurate (in every way). Their new 72 scale Arrow kit is pretty much a scaled down version of that one.

For those that are interested, I offer 1:72 Arrow decals that correct all the issues with the kit supplied sheet and improves on the older AM sets as well. I have a 1:48 version in the works

thanks

David

Edited May 27, 2013 by DavidWinter

[robvulcan]

watching this with much interest I love the arrow what a beautiful plane she was.

[k5054nz]

Very nice work so far! Watched "The Arrow" for the first time in years the other day and that really, really made me want a kit.

[John R]

It's been a long time but it some progress has been made. Gloss white finish is Alclad white primer sealed with Alclad gloss kote. The easiest way to get a gloss white finish that I have found.

The latest unforeseen problem was that the masking tape, a Tamiya lookalike from Tristar models, left a gooey deposit which needed to be removed with white spirit.

Next step decals. I do believe the end might be in sight!

John

Edited September 23, 2013 by John R

[thomastmcc]

cool build i have one or more of this kit..

thomas

[Vlamgat9]

Wonderful. Had missed this build. Really great work.

[Caerbannog]

Wonderful Arrow. And an excellent topic

[Martian]

It's looking really nice!

Martin

[Scooby]

There is a much better decals sheet produced by Canuck Models, the Arrow Graphic decals are very dated.

Nice choice of build. My father was a RCAF liaison on the Arrow project. He played soccer (football) with all the test pilots.

http://www.canuckmodels.com/

Edited September 28, 2013 by Scooby

[John R]

Unfortunately they are for 1/48 scale. I did not have a happy time with the Arrow Graphics decals. They were very thin and had a tendency to break up.

Photos of the decalled model will appear very soon.

John

[Navy Bird]

Unfortunately they are for 1/48 scale. I did not have a happy time with the Arrow Graphics decals. They were very thin and had a tendency to break up.

Photos of the decalled model will appear very soon.

John

Canuck makes the sheet in 1:72 too.

Cheers,

Bil

[DavidWinter]

Hi John.

Bil is correct, I offer that set in both 48 and 72 scale (actually the 72 scale is going on a year old now).

Thanks, and good luck with the rest of your build.

David

Edited September 29, 2013 by DavidWinter

[John R]

David - Sorry, I only went as far as the first page of your website. I also forgot that in an earlier reply to this post you mentioned the availability of the 1/72 version. (it was a long time ago!)

This is as far as it's got. It is suffering from a spell of 'getfinisheditis' so I could take it to my model club meeting. The u/c needs attention and some other fettling is needed before it's 'ready for inspection'.

John

Edited September 30, 2013 by John R