The first steam waggon made by Sentinel (Shrewsbury) Limited was in 1915 and was called the "Super Sentinel" Steam Waggon.
In 1928 this vehicle was superseded by the double geared steam waggon fitted with a two cylinder double acting engine and further modifications were made until the production of steam vehicles ceased at the end of 1937.
The engine was capable of developing 70 b.h.p. in early cut off, and 110 b.h.p. in maximum cut off for a short duration. The boiler was of watertube construction with circular firebox with a working pressure of 275 lbs. per sq. in.
A water tank of 120 gallon capacity was fitted at the rear of the vehicle which had a pay load of approximately 7 tons, weighed 12 tons gross.

The (Y4-1) Sentinel Steam Waggon was the fourth model to join the range in 1956.
Collectors sometimes call it an emerald truck, and in mint condition with undamaged paint and decals, it's really a small semi-precious stone.

Interesting Notes: The Sentinel Steam Waggon (the double g is correct apparently) was made from 1956 to 1960. It was one of the Yesteryear models to be in production for the shortest time - just four years. Lesney stopped its production prematurely because his molds soon wore out.

Variations/Rarities: A very plain little model with few variants to it.
Always blue with a black chassis and the lettering 'Sand & Gravel Supplies' on the sides and on the cab with just the top of the chimney and a small box on the side of the chassis trimmed with gold paint.
The first variant is the small box under the 'P' on the side decal - it is mostly found painted gold but a few turn up unpainted and probably an early model and then enhanced for more sales or just an error model.
The other major change was to the wheels which were daisy type metal all its life except at the end when, presumably, they ran out of wheels and used the black plastic ones to finish the run. These were classed as rare originally but nowadays more scarce to find.
One interesting feature are the models without the window center roof support. This was a result of the fettling process where the bar got broken off but the model was still passed through and sprayed but no monetary value is placed on this variant.
The axles were mostly crimped but final runs were riveted and in the hard to find 'B' type box.

Values don't seem to be particularly high - but it's not a model you see every day.
There is only one variation which affects value and that is the wheels. The very last releases had black plastic wheels, while most of the run had grey metal wheels. It is the black plastic wheels you should look out for.

Scale: 1:100

1928 Sentinel Steam Waggon

Grenodised 8 spoke wheels; black box

Grenodised 8 spoke wheels; gold box

Black plastic solid 24 tread wheels

Without the window centre roof support