David Herbert

When I fill my car petrol is pumped in. AvGas is no more volatile than ordinary car petrol (just more heavily certified and higher octane which makes it less volatile under compression). I would suggest that trying to get fuel from a tanker into an underground storage tank at a filling station is simplest by gravity but getting it into the tank of a bomber that is higher than the tanker is not going to happen by gravity so some sort of pump is necessary. David

Well done Rich, a search of the census for Wimbledon aught to find E.H.Allen - possibly even still alive ! I note that the stitching of the leather pieces on the lids was done after the writing inside as there is no ink on the thread. I had no idea of the origins of the NHS numbers, great piece of research. David

The FV421 that went to the Tank Museum is 00CA25. It had previously been a range buggy at Porton Down range (not a NBC target!) and before that had been heavily rebuilt several times testing transmission and steering systems and hull and suspension refinements of the FV420 program. It finished up with a RR B81 engine and inline Allison 6 speed fully auto transmission coupled to a controlled differential steering box with aditional brakes on the input to the final drives which enabled it to pivot turn at low speeds and gave better steering in water. This same powertrain was rearanged for early FV432s by placing the engine beside the transmission instead of in the middle of the cargo area (inherited from universal carriers). I have never found any photos of 00CA25 before it went to the Tank Museum - has anyone got any ? David

Well done, I didn't spot that, yes it is. At the time your father worked at MVEE they were doing a great deal of work developing what became the FV430 series. A lot of that work was done on FV420 series vehicles, mostly the FV421 unarmoured load carriers. Do you have any photos of these that you can share as I have a particular interest in FV421 ? David

Not a Centurion but a Conqueror with a dummy turret as ballast for automotive trials. It looks like it has Chieftain track fitted which has rubber pads unlike the standard Conqueror track as shown in the B&W photos. David

I am sorry John but no ! Sherman tracks pins do not come out even if you want them to. They are rubber bushed into the track link, two per link. The links are then joined by removeable 'End Connectors' which also extend away from the ground to include the guide horns that form the path for the road wheels. The end connectors are retained on the pins by wedge bolts that engage with flats on the pins, a bit like the cotter bolts that hold a bicycle crank onto the sprocket shaft. The nut that holds the wedge in is on the upper surface of the end connector so the drive sprocket has cutaways between the teeth to clear these nuts. The sprocket teeth actually drive onto the end connectors so when there is too much wear the end connectors can be replaced together with the sprockets disks. When it was realised that standard 16 1/2" Sherman VVSS track ground pressure was too high the quick fix was to make end connectors with sheet metal extensions welded on to them. As seen in the photos above there were several different designs of these. Even after HVSS 24" track solved the ground pressure issue there were a huge number of VVSS Shermans in use and some were remanufactured with all the suspension units spaced out about 4" from the hull to enable extended end connectors to be fitted on both sides of each track. David

I am very impressed that Clive has a photo of a bulb with a broken filament. I just throw them away ! David

A Hymac 590C is a crawler mounted 360 degree excavator and thus a totally different machine to 28KB36. I believe the 'T' suffix denotes extra wide tracks but I don't have documentation to prove that. There are lots of photos of HM 590C on google. I think that the "(Modified)" relates to the armoured 'Cab'. I have seen these in service with armoured cabs. I have no idea what 28KB36 is but it seems to be a low ground pressure tracked carrier or dumper. Probably a standard commercial plant design. David

I am guessing that the manilla rope specified is 2 1/4" circumference not diameter which would result in it being about 3/4" diameter. That would be plenty strong enough but a bit small to grip in cold weather. 2 1/4" diameter would be a bit too thick I think. How do people remember these ropes ? David

The canopy frame as shown in your photo of a Bedford RL is most definitely NOT a roll bar. A roll bar is capable of supporting the weight of the vehicle in a roll over accident. It could certainly be designed to also support the canopy (another word for canopy is 'tilt') but whether on a Land Rover or Bedford RL, a few bits of small gauge tube are not going to provide any safety protection whatsoever. Incidentaly the standard military contract Bedford 4x4s had their headlights about 6" lower to comply with lighting regulations and also had an open area where the Bedford badge is on the one in the photo to give better cooling. I am guessing that the one in the picture is a prototype using a standard S model cab. Good luck with the model. David

A printer/scanner that will scan 35mm negatives aught to scan fiche to a readable standard if used on its highest resolution and limiting it to relatively small sections of the fiche at a time. You can then crop each of the resulting images into seperate pages, save each page seperately as JPEGs and create a folder to keep them together. Have fun, David

This truck is a great find. The cabs were rotting out on these 30 years ago so to find one that looks this good and complete is very rare. They are great to drive and quite reliable once you get them right. And wonderful to have two in-service pictures too. David

Actually all British WW2 and later cruiser and heavy tanks had rear drive, USA went to rear drive from Pershing onwards and Germany went to rear drive post WW2. Front drive results in either a drive shaft under the turret (raising the profile of the tank) or having the engine at the front which is better for an APC or SP Gun or IFV but less good for a tank as it limits gun depression when cresting a hill and exposes more of the tank if trying to shoot round a corner. Short tracking is used regardless of front or rear drive and usually only on one side (because of damage) but if the sprocket is not still engaged with the track, that track is not driven or braked and the vehicle is uncontrolable and must be towed on a hollybone drawbar. It is pretty obvious that the universal carrier shown in the first post is rear drive and so can still be driven but Loyd carriers have sprockets at both ends. The front one drives and brakes but the rear one also brakes to give more positive steering. One could still drive with the rear sprocket out of use but would have to be careful. TJSB replied faster than me and I agree with his comments. David

This is a 'get you home' solution known as 'short tracking' that you use if you have damaged an idler or track and don't have spares available. I agree that the photo was taken on a training excercise as the guys don't look too stressed. It can be employed on most tracked armoured vehicles if necessary. It would normally only be done on one side of the vehicle which again suggests that this photo was of a training excercise. David

Hi Sean, No, I haven't needed to do it on a 214 but I have done it on a Chevy 250ci 6 cyl which oddly enough is rather similar but a bit bigger. I have no doubt that it is the easiest and simplest way to do what you need to. If you were doing all the valves it would probably be worth making a lever that would engage with both sides of the valve retainer but give access to the collets. I made one up for an engine with studs for the rocker shaft and made a short dummy rocker shaft out of an old piece of pipe to save stripping the rocker shaft. I have also used the rope method to lock the crank on a chainsaw to undo the flywheel retaining nut. David