Correcting the Airfix Mk1 tank

[TeeELL]

I guess most of you will be familiar with the story behind the ‘wrongness’ of this, otherwise delightful, little kit.  For some unknown readon I’ve been an enthusiast of the ‘rhomboid tanks’ for several decades and have both Airfix and Masterbox kits.  I’ve purchased ‘correction kits’ from several sources and everyone of them I’ve found wanting in one respect or another.

I’ve decided it is time to have a go - ‘put my money where my mouth is’ so to speak.

I am planning on addressing the following:

Wider, detailed cab

Corrected roof

Corrected ‘male’ sponsons

 

I have also downloaded a 1:18 scale track link which I have re-worked to suit the track run of the Airfix kit.  I was able to print it in 1:76 scale by reducing it to 23.68%.   From that single link I have been able to create 6, 8 and 10 link lengths as well as creating rounded pieces to fit the 2 sharp radius ends.

This is the cab under development. I did a test print and it is a drop in replacement for the original part although that previous version had finer rivets which didn’t match the kit originals.

 

[TeeELL]

Since my last post 2 things have happened, firstly the CAD drawing (version 😎 for the rendering of the cab, as in the previous post, has become corrupted.  I have had to roll back to version 3.  Not quite as bad as it seems as the cab was actually a fraction too wide; I am having to use the kit dimensions and not the actual dimensions for this.

The second thing has been the completion of the main roof section:

 

Last night I printed the roof and the revised, but still basic, cab:

 

The lip at the front of the cab section has rivet detail and serves to cover the join that is all to obvious in the kit.

[Ebf2k]

Looking great!

[Brandy]

Any progress on this?

It's not at the top of my build pile, but it would be great to have someone who knows tanks better to do this, and I can concentrate on the stuff I know!

 

Ian

[TeeELL]

On 1/29/2024 at 3:41 PM, Brandy said:

Any progress on this?

It's not at the top of my build pile, but it would be great to have someone who knows tanks better to do this, and I can concentrate on the stuff I know!

 

Ian

Hi Ian,

  I’m afraid ‘other stuff’ has delayed my progress with these parts.  I am happy with the replacement ‘roof’, it prints well and fits and the front piece also works well with a ‘riveted strip’ (prototypical) that hides the original join; I need to add all the extra details to that part.

the track sections work well and despite the scale difference are good for the Airfix, Emhar and Masterbox ‘rhomboid tanks’, the articulation joints between the track plates are apparent especially where the tracks pass around the ‘horns’.

[TeeELL]

I have just had a weeks holiday and took the opportunity, whilst away from home, to work on the parts for the Airfix Mk1 tank.  The cab I pictured at the start of this thread ‘disappeared’ the file becoming corrupted somehow.  I had to start all over again.  With the exception of the towing extension the cab is finished and will be test printed this coming week.

 

 

 

In addition I’ve created 3D printed link and length tracks (in the following photo the tracks can be seen fitted to a MasterBox Mk1).

 

[TeeELL]

Once I am happy that these are OK, they will be made available to order.

[badger]

Ooh - yes please to the tracks!! I've got a couple of the masterbox ones in the stash somewhere.

[TeeELL]

I’ve received some positive feedback from Helen (Mk1Nut) and need to do some minor tweaks.  The plates above the exhausts and the positions for the cab periscopes.

[TeeELL]

I’ve posted details of my tracks for the Airfix Mk1 and their success has inspired me to get on with completing the cab drawing for printing.  In addition, I’ve done some minor changes on the ‘roof’ correcting some positions of isolated rivets and taken onboard the comments by Helen.  
I will have a go at creating tracks for the Masterbox Mk1 tanks using the same system of measuring lengths and angles that worked so well on the Airfix model.  I’ve designed my own track plates so scaling them from 1:76 to 1:72 will be straightforward.

[Listel]

Nice job! Let us know when all the bits are completed and ready to be ordered 😉

 

Cheers,

François

[TeeELL]

The cab only needs the tow bracket to be created which will be done shortly.

 

Once this has been done and I’ve run a test print, they will be available.  By and buy, I will create a correct pair of ‘male’ sponsons as the kit parts are very wrong!

[TeeELL]

A very obvious feature of the early rhomboid tanks is the design of the track plates which isn’t something that can be replicated with ‘rubber band’ type tracks.  Having designed my own 1:76 scale track plate, I then measured the lengths, diameters, angles and distances between centres of the Airfix Mk1; Transferring those details into my CAD drawing, I was then able to place individual track plates around the shape.  When finished I had a 3D printed complete length - the big test being, of course, would it fit?  Well to my delight it did fir - perfectly:

 

the photo shows my new 1-piece track - a first prototype (it needs slightly modified print supports.  On the grey ‘female’ mule are fitted my original ‘link and length’ version.

The design of a one piece track obviously works with an unattached outer rhomboid part, but a sharp blade will separate the track such that it will fit a ready built model.

 

Both the replacement roof panel and the wider cab have now been completed.

[TeeELL]

I need to see if I have a ‘green plastic’ kit in my collection of unbuilt Airfix Mk1s that way the resin parts will stand out.

[TeeELL]

It has been a while.  I’ve spent a great deal of time trying to find the best print support for the tank tracks, just before SMW I finally succeeded.  In addition, I’ve done some revision/correction to the cab and the roof.  I am now in a position to offer them at £10 per set = pair of tracks + cab + roof + exhaust V covers.

For 1:72 Masterbox and Emhar tanks, I’ve created the tracks - for the Masterbox, but they fit the Emhar, I just need to make the supports the same as those on the Airfix tracks.  These will be £5 per pair.

[TeeELL]

On 4/21/2024 at 7:31 PM, badger said:

Ooh - yes please to the tracks!! I've got a couple of the masterbox ones in the stash somewhere.

Badger, the tracks for Masterbox have been designed and the test print worked.  I need to revise the print support though (there are about 180 of them, individually placed!!).

[badger]

On 23/11/2024 at 21:43, TeeELL said:

Badger, the tracks for Masterbox have been designed and the test print worked.  I need to revise the print support though (there are about 180 of them, individually placed!!).

Apologies for the late reply - not been around much recently during to other things taking over my hobby time.

 

That's great news - I'd be in the market for a couple of sets once they're finalised, and there's a few of your Javelin sets I'd like to add to make up an order.

Kind regards 

Ben

[TeeELL]

Ben,

 I am going to print 2 sets of the Mk1 tank parts, I’ll pop a photo on here when one is done.  I am a bit overwhelmed with other stuff so I’ve no idea when the remaining parts will be produced.

Javelin parts readily available (printed to order).

I’ve still not yet cut the nose of my ‘mule’ to create the ‘short radome’ marks.

[TeeELL]

Here is the photo promised, the tracks fit between the rhomboid halves requiring just a bit of plastic removal at the ‘horns’.  The roof and the wider cab are direct replacements with the cab having a rivet line to hide the gap between it and the bottom panel.  Included are the V exhausts (with one for the carpet monster).  It has taken a while, but I finally found a print support arrangement that prevented the slight curve in the lower half of the track run (visible in an earlier posting).

 

Immediately available.  Well subject to preceding orders!

 

[badger]

I'll drop you a message re an order when I get in.

[badger]

PM sent

[badger]

Tracks (and some other parts) arrived safely today, very well packaged which kept them safe from the postie.

Highly recommend @TeeELL  - his creations and service are both excellent!

[TeeELL]

52 minutes ago, badger said:

Tracks (and some other parts) arrived safely today, very well packaged which kept them safe from the postie.

Highly recommend @TeeELL  - his creations and service are both excellent!

Thanks, I appreciate the kind words.