Bovington Churchill Tank Project

[Dennis Jones]

Hi all,

Gill has given me permission to publish this article and photos on the website as we thought it would be of interest to some people. It was donated to the Tank Museum at Bovington in approx 1960.
This an approx 1/6th scale Churchill MK IV tank (50 inches long and weighs a lot) with an SBG bridge attached. It was built in 1952 by Allan Tamplin and took 5000 man hours, it was exhibited at various Model Engineer Exhibitions and appeared in the UK and Foreign Press. It was a running and functional model. I have been asked to try and restore some of it's working functions but as you can see that is a daunting task. It would appear that it was powered by 12 volts, the battery used was a car battery by the type of terminals used. The big motor in the centre drives two gearboxes on either side via two chains and solenoids operate clutches. There are also two other solenoids under the gearboxes which operate brake shoes against the clutch housings. The control box (that handle is one foot long) operates over two wires and has an escapement rotary switch in the tank, similar to the old reed radio control sets. A lot of the wiring has perished, at present I am looking to get the motor running but it has 5 connections and is difficult to know what goes where as I have no plans or diagrams.
The track links are made of brass and as far as we can tell must have been made by hand. The two winches at the front and rear are to raise the bridge assembly. The are ten switches dotted around the tank and goodness knows what they do. It also has a turret with moving parts in that as well.

Anyway I will keep you posted on what transpires.

Dennis.

[Paul Morris]

Hi Dennis.
Brilliant, I was privy to have a little look at this model the other week when your name was mentioned I knew you would be pleased its a hell of a model isn't it but my God look at those wires
Good luck looking forward to seeing the next instalment.
Cheers Paul.

[William Bath]

Now that is some serious work, makes my Tiger overhaul look like an Airfix kit

[Leon Benjamins]

Wires

[Adrian Harris]

"I love the smell of Paxolin in the morning..."

Looks like you've bitten off quite a chunk there Dennis

Given the age it was designed and built, it would be worthwhile checking if the thing is completely insulated, positive earth or negative earth.

Look forward to another bridge laying demonstration at Tankfest

Adrian.

[Per Sonnervik]

Hi Dennis,

I´m glad that this tank survived as I´ve been wondering what might have happened to it.

Here´s some articles and photo´s from the Model Engineer mag. the first without the bridge;






and the last I´ve found (from 1954) but unfortunately no building description or information to help you;





It will be interesting to see what you can do with this model.

Regards,

Per

[Dennis Jones]

Hi Per,

That's great to see, is there any more info on it or is that it. I have been on to Model Engineer Mag site but it appears their archive on line only goes back to 1990. Any info would be welcome. Perhaps you could email me the images at djones49@talktalk.net.
Thanks again.

Dennis.

[Dennis Jones]

After 60 years in wind and rain we have signs of life. Sorry the video not very good.
We are operating with 12 volts and found it is a compound dc motor and by trial and error seemed to have found the right connections, there are five going into the motor. The clutches are operated by two solenoids, left and right and there are two other solenoids which I thought might be for reversing the gearboxes but it turns out they apply brakes to the clutch housings. We can reverse the main motor by reversing the connections to the armature connections on it. We have also tested the bridge winch motors and they work as well.

Dennis.

[Dennis Jones]

Just checking loading and climbing ability.

Dennis.

[Dennis Jones]

Some more photos showing the tank with the turret on. The motor to drive the turret is inside the turret and is powered by slip rings and brushes on a central shaft. It works but unable to reverse the direction of the motor as again it is a compound motor and this one unlike the winch motors is wired internally. We removed a side panel as you can see and lo and behold there is a copper cylinder with the outlet pipe connected to a 12 volt operated valve whether this is some form of smoker we are not sure. We have now since found out it was used for "spraying water on little boys wishing to tamper with it".

Dennis.

[Adrian Harris]

Looks like a good little mover

But you've got to do something about that "fingernails-on-a-blackboard" squeak that's coming from somewhere

Adrian.

[Dennis Jones]

This gets even better. I published a post in the Model Engineer Forum and I got a couple of replies. The one below was published in the Milwaukee Journal in 1951, how these people remember these things beats me as I can't even remember what happened yesterday let alone 60 odd years ago. I think the article titled "Thanks to tank living room unfit for living" explains the copper cylinder as he says in interveiw "to spray water on little boys who wish to tamper with it", now there's an idea !!!!!

Dennis.

http://news.google.com/newspapers?nid=1 ... 84,2507950

[Dennis Jones]

Some more articles and a photo, notice the Duke of Edinburgh peering down at it. These came from a posting I made on the Model Engineer website. We have now picked up the bridge from the Museum and are trying to figure out how it worked and will be posting some more photos later.

Dennis.

[Dennis Jones]

Managed to get a photo of 1/35th scale of the tank. At least we can now see how the bridge was controlled. We thought that the A frame was mounted on the tank but as you can see from the photo it is mounted on the bridge. We had only one half of the A frame but I have managed to fabricate an identical one to match.

Photo of 1/6th scale version, some work to do on the pulley and cable system as the winch motor did struggle a bit. Looking at the 1/35th scale version if that is accurate then it looks as though the bridge was raised by hand winches. Total length when down 10ft 6ins or 3.2mtrs.

Dennis.

[Dennis Jones]

Removed an aluminium cover yesterday as there seemed to be a lot of wires going through to it and low and behold the radio control receiver was uncovered. The battery in the foreground is 22.5 volt used as ht for the double triode valve. Have had to replace both winch motors as the old ones didn't have enough power to raise the bridge. New radio control equipment arriving ths weekend.

Dennis.