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Great work getting it to bend nicely - hot water and heat gun are certainly more painful.

Ad Lav wrote:Great work getting it to bend nicely - hot water and heat gun are certainly more painful.

Thanks, Adam. Unless you have plenty of the right gauge Plasticard around, it's too risky using a heat gun for a job like this- as I learned the hard way, on the Cromwell build.
Even before I set out warping this panel, I made sure I'd drawn its profile in pencil on a sheet of styrene... just in case

Yip they look the business .
Been a lot of footage on tv recently with the 75th anniversary of D Day, so hot to see loads of Cromwell and Comet details.
Of course the Villiers Boccage event featuring heavily.
Nice job so far matey

HERMAN BIX wrote:Yip they look the business .
Been a lot of footage on tv recently with the 75th anniversary of D Day, so hot to see loads of Cromwell and Comet details.
Of course the Villiers Boccage event featuring heavily.
Nice job so far matey

Many thanks, HB! if the tanks at Villers-Bocage had been Comets, instead of Cromwells, I'm sure the outcome would have been very different. While this incident is often cited as an example of the superiority
of the Tiger 1 over opposition hardware, it's also worth noting that the Cromwells were trapped, and couldn't use their superior speed and manoeuvrability.
As an aside, I wonder what the outcome would have been if the Cromwells had been some of the marine equipped Centaurs, with the 95mm howitzer. ( The Centaur was a less refined Cromwell, deprived of the 600BHP Rolls-Royce Meteor engine, and stuck with the unreliable Liberty motor.) However, the close support howitzer fitted to the Centaur could do some serious damage.
According to David Fletcher, in his "British Battle Tanks' (Osprey, 2017):
"...in 1942, in keeping with the typically British skill at improvisation, a new gun was created by combining the breech of the Royal Artillery's beloved 25-Pounder, with the barrrel liner of the 3.7in anti-aircraft gun.
The result, known as the 95mm howitzer proved to be a remarkable weapon. Firing a respectable HE shell it had a maximum range of 6,000 yds; firing High Explosive Anti-Tank (heat) rounds it could theoretically penetrate 110mm of armour at any range it could reach...." This would have been enough to knock a Tiger out from the front.
As a footnote, Neither the Cromwell nor the Centaur went to war mounting the 6-pounder gun (the 6-pounder was reamed out to 75mm, so that it could fire the US HE round).
Fletcher adds: "...This was a pity since, with the introduction of Armour Piercing Discarded Sabot (APDS) ammunition in June, 1944, the Mk V gun proved to be an excellent anti-tank weapon at close range. It could penetrate 108mm of armour (which over-matched the Tiger's front plate) at 1,500 yards, and at any range up to 2,000 yards was second only to the legendary 17-pdr..."

I'm busy planning the next stage. I'd like the lower hull primed and rolling, before returning to the turret and the complexities of getting the Mantlet fixed in place and working with some form of elevation, and recoil.
That's for much later. Right now, I'm adding all the bits to the upper hull the Comet will need to resemble a type A Comet. Getting pics of the tank from above is nigh on impossible, since all the online shots tend to be of the frontal or profile type. Even then, using blueprints has thrown a few spanners in the works, as the two I have sometimes contradict one another in terms of component placement, as well as deimension.
So...... I managed to find the definitive Comet book online and...it's packed full of pics and period diagrams that will never be found online. It deals with the development of the tank, almost down to the bolts and washers, as well as the tests prototypes underwent at Lulworth and elsewhere.
This is it: On the cover, there's a pic of the very first prototype. A cursory glance shows that it had no return rollers, and sported Cromwell trackguards, for starters. (Click to ENLARGE)
Here are two samples of the type of technical illustration in the book (285 pages, by the way.)
There's a bullet 'splash' test on the Loader's hatch, which as a hastily improvised shield in front of it.

I noticed that all production Comets had a defensive 'splash' strip fitted immediately in front of the Loader's Hatch. Mine will have to have one as well. There are also three such splash strips at the base of the Visor Panel, where it meets the Glacis plates. I'll have to have those too, and you won't find them in the kit.
Here's a very useful pick of the All Round Vision (ARV) cupola. This will help me to determine the best hinges to fit to the hatch.

Dinner time now. I can smell something burning in the oven (as usual )

Gradually getting the main detailed parts into place. Quite a few have to be made from scratch, as they're not included in Christian's flatpack basic kit, nor in his list of specialised extras for British tanks. This is where Shapeways can be useful as a source of printed components. Many British WW2 tanks shared parts (for obvious reasons), such as aerials, Headlights, spotlamps, MGs, Gunsights, hinges and so on.
Luckily, I have some extras from Shapeway's Cromwell offerings. (From Woz, and others).
In this instance, however, I managed to buy some metal BESA MG extractor fan Cowls from Christian. Both the Hull and Coaxial MGs needed extractor fans to rid the Fighting Compartment and Turret, respectively,
of the nasty, and fog-making gasses given off by the BESA MGs, when fired.
However, I've found that weighty pieces such as these often come adrift from the styrene they are bonded to, when snagged. In addition, I really didn't want to have to drill through to them from the inside to add additional supporting rods/screws to reinforce the epoxy bond.
So....I decided to scratch build the parts with offcut styrene. Us usual- do Click on the pics to ENLARGE them. One thing I noticed, after the event, is that whilst the Comet and Cromwell share the same basic gas extraction system, the Comet Cowl is actually round, and doesn't have a small segment cut off the edge
like the Cromwell. I may have to mould the trimmed off edge back on in time, if its absence begins to niggle...

Then, I began working on the hinges for the Cupola Doors. They were included in the kit, and so I didn't have to make them- but fitting them can still be tricky:

It's still good to have openable hatch doors:

In front of the Commander's Cupola, there's a defensive 'splash guard' to deflect bullets away from the Commander, as well as the periscope lenses. There's also a smaller defensive strip fitted in front of the loader's hatch- but I've yet to make that.
Grooves for the fittings are already in the turret roof, but if you want the splash guards, you'll have to scratch build them, as they are not part of the kit. This is how I did it: Calculating the angles for the guard can get the old grey matter working hard. I use printed blueprints, as well as the Computer monitor. I made some little fillets, in stages, to support the guard Calculating the angle of the guard was the hardest part, as the angle also determined how much I'd have to trim the fillets by. I scaled the blueprint up on the screen so that it was just about 16 inches long, and that's just about the length of the model. Given rough parity, I then compared the angle of the splash guard on the Blueprint with that on the part I was fabricating.

Success.

You can see the Cupola Splash Defence clearly in the pic of an Irish Comet...if you click on the pic, that is.

I also found that whilst the shape of the arms holding the Driver's and Gunner's doors was basically correct. It was just a shade too long. In reality, the arm extends about halfway along the door. Thereafter, there's a catch and a grab handle. The way I had it before, there was no room for the grab handle. After I nagged myself enough, I got around to making the arms the correct length and profile. Then I added some staples modified from 10mm in breadth, to 8mm. That size looks about right. In the kit, the arm supplied is simply a rectangular length of styrene. How you fashion it to look like the real thing, is entirely up to the builder. However, the real thing is so distinctive that it merits a real effort to get the shape and length right. The amount I removed from the pivot arm is indicated by the red lines.
I also fitted some sidelights to the front Mudguard support brackets. These were bought from Shapeways (a Woz creation, if I remember correctly). I also rounder the brackets bend off. It's curved on the real thing, not angled straight lines. It will all look so much better when the rough edges, and surplus glue, have been cleaned up. There's a mass of fine sanding and tidying up to do, before this model ever sees any SCC15-Olive Drab