Matchbox Tempest II with enhancements

[TeeELL]

Since my ‘revelation’ I have created the following:

 

the 1 piece cowling with fitting lip:

 

Centaurus ‘engine’ less gearbox:

 

The separated ‘gearbox’:

 

now the parts can fit together.  The painted ‘engine’ and interior of the cowing can be fitted together after painting and the whole fitted to the front of the engine nacelle.

 

A view into the front of that assembly:

 

Finally I can add the painted ‘gearbox’, prop and spinner after the model has received its final coat of either HSS or Cammo (undecided just now).

 

It has taken me about as long to create this text and add photos as it did to edit the CAD drawings!

 

[Brandy]

Nice! I did similar with my Pegasus DH4. The difference made by 3 very simple printed parts (cowling lip with cooling shutters, radiator, and engine nose) is huge. Well worth the effort!

 

Ian

[Graham Boak]

Thanks, I hadn't noticed one, but it did seem a strange omission so I wondered.  

[Sebastien]

On 10/15/2024 at 4:09 PM, Brandy said:

I think it's safe to say that's an improvement!

 

 I think it's safe to say  THAT is an understatement.

 

[CarLos]

Congrats for the great work!

 

[TeeELL]

Thanks for the encouraging comments.  I’ve assembled an engine/gearbox print into a cowling ring:

 

With that proving to be a good fit into the cowling, I assembled the 3 components of the Matchbox propellor:

 

yep - can’t really see anything!  However, with a bit of paint applied something might show?

[Brandy]

Altogether now..."but you know it's there"!

 

Ian

[TeeELL]

This is an image of the 3 components ‘in the flesh’.

[stevehnz]

I'm pleased to see this happening, I'd be keen of a set of these pieces. A few years back I modified a Matchbox kit into the prototype Mk II but was never happy with the front of the cowling shape, even though I did try to sand it to a more rounded profile, I was worried about sanding right through the plastic.

My model.

 

the real thing

Steve.

[TeeELL]

Steve,

  once I am happy that the pieces fit as they should, I would be more than happy to supply you with them.

[TeeELL]

I am off to a slow start with the model itself (various reasons) but I’ve removed the dimples representing the exhausts and drilled a fitment hole for the ‘floor’.  Things should really start to move next week.

[Galligraphics]

9 minutes ago, TeeELL said:

once I am happy that the pieces fit as they should, I would be more than happy to supply you with them

There might be another one or two of us interested in those parts 

[TeeELL]

2 hours ago, Galligraphics said:

There might be another one or two of us interested in those parts 

That is fine, things are progressing to the point where they are viable, but I want to assemble the model to ensure everything is OK.

[TeeELL]

11 hours ago, stevehnz said:

I'm pleased to see this happening, I'd be keen of a set of these pieces. A few years back I modified a Matchbox kit into the prototype Mk II but was never happy with the front of the cowling shape, even though I did try to sand it to a more rounded profile, I was worried about sanding right through the plastic.

 

Steve.

I see that the exhausts on the prototype appear to be ‘siamesed’ (still don't understand how 18 cylinders exhaust through 8 or 16 outlets!??) the contour of the cowling is very different to that of the kit or, as far as I can tell, the production aircraft.  Creating that shape cowling is a, maybe, 10 min job in Fusion 360!  Creating the siamesed exhausts a little more time.  It is the supports for printing that are time consuming!

[TeeELL]

Work has actually started on the build although slowly.  I’ve removed the exhaust stubs and I am removing the ‘grill’ doing each half but I’ll not trim to fit until the 2 halves are together.  The ‘floor’ has been test fitted in the fuselage and has worked satisfactorily.  I’ve splashed a bit of paint on a ‘Centaurus’ so I can see if it is effective when inside the cowling.

With the kit exhaust stubs removed there is more space than I anticipated so I can adjust the CAD drawing and reprint my exhausts to fit better.

[stevehnz]

12 hours ago, TeeELL said:

the contour of the cowling is very different to that of the kit or, as far as I can tell, the production aircraft.

Afaics, the production Tempest II & the prototype had the same cowl shape. There is something wrong with the proportions of the Matchbox Tempest & although I haven't measured it, I suspect the detachable cowl panels are too wide which has forced the curved front of the cowl to have a too severe radius to get to the correct cowl opening diameter.

For comparison, production, albeit restored. Photo by Damien Burke from this website. Used for comparative purposes only.

Prototype again.

Not too much difference in them.

Steve.

[PattheCat]

Well,  I came to see the build of a kit I really liked when in my early teenage years (attracted by the box art but took it because of the Indian markings). Now I find it to be brought up to an entirely different level.

Impressive work @TeeELL. Keeping mouth from gaping and both eyes wide open.

Cheers.

Pat.

[Andrew]

11 hours ago, TeeELL said:

I see that the exhausts on the prototype appear to be ‘siamesed’ (still don't understand how 18 cylinders exhaust through 8 or 16 outlets!??)

 

There are exhausts for two more cylinders beneath the engine, roughly level with the wing leading edge. They're represented on the Matchbox kit by two small ports/dimples.

 

Great progress with your enhancements @TeeELL, and I'd love to add my name to the list of interested folks please.

[TeeELL]

6 hours ago, stevehnz said:

Afaics, the production Tempest II & the prototype had the same cowl shape. There is something wrong with the proportions of the Matchbox Tempest & although I haven't measured it, I suspect the detachable cowl panels are too wide which has forced the curved front of the cowl to have a too severe radius to get to the correct cowl opening diameter.

For comparison, production, albeit restored. Photo by Damien Burke from this website. Used for comparative purposes only.

Prototype again.

Not too much difference in them.

Steve.

Steve,

  that is very, very helpful.  The cowling is most assuredly longer than that provided by Matchbox.  I shall scale the photos and do some measuring.  There might be a need to compromise otherwise I may end up designing and printing a complete replacement ‘front end’!

[TeeELL]

Of course, 

  thank you @Andrew.

[TeeELL]

I have downloaded a number of photos of Tempest II aircraft featuring their side profiles and, as @stevehnz has pointed out there is a significant difference between the actual shape of the front cowling and the Matchbox rendering and, of course, mine.  Once I’ve scaled the photos I shall check the various dimensions and determine how to modify my CAD drawing and 3D print.

Having had a fitful nights sleep (or lack thereof) I have worked out a couple of templates that will help position the ‘floor’ and the seat in the kit.  
 

For anyone interested in acquiring these 3D parts, I will list them here:

https://www.britmodeller.com/forums/index.php?/topic/235146116-matchbox-172-tempest-ii-enhancements/

 

[TeeELL]

Using CorelDraw, I have imported 3 photographs of side profiles all at virtually the same angle; each has been sized such that the front of windscreen/fuselage point and tip of spinner at at the same distance.  Reference lines to the scale length of the aircraft have been added as a cross check.

These are my findings:

From the trailing edge of the exhaust panels = (the join in the kit):

length to exit point for exhausts (excluding the ‘stubs’) 10.0 - kit is close enough.

to the rear of the engine shroud 12.6mm - kit is close enough

to the rear of the cowling 23mm - kit is 22mm

to front of cowling 28.6mm - kit is 27.5mm

These can only be approximate, but are certainly within 0.5mm.  I have mentioned that an increase in length of the cowling by about 1mm would make it ‘look right’ and this seems to back that up.  I shall redraw the cowling ring and see what it looks like.  Standby to standby!

 

[TeeELL]

This is how the 2 compare.  By simple changing one dimension the cowling has become much more convincing (in my opinion).
 

 

Now to print it.

[stevehnz]

I can see a razor saw in my Tempest lI prototype's future.

Joking aside, I think you might have cracked it, it was nigh impossible to make it look right as it is. 👍

Steve.

[TeeELL]

35 minutes ago, stevehnz said:

I can see a razor saw in my Tempest lI prototype's future.

Joking aside, I think you might have cracked it, it was nigh impossible to make it look right as it is. 👍

Steve.

Steve,

  It is all thanks to your input.  The parts are printing just now,  should be ‘done’ in about 2 hours (because I’m also printing some revised other parts).