OT: Ye olde road compactors query

[Tim Downie]

Well done! Not exactly right but close enough for me to track down this picture of a Benjo Rammer

at those flames! Now there's a serious power tool. ;-)

Tim

[Tim Downie]

quick link to the bigger picture here.

[Mary Fisher]

LOL!

I'll have a look :-)

Mary

[Bob Minchin]

Tim, I presume you have also found this

history of the company who made them.

Bob

[Andy Dingley]

Toolstation, 16 quid. Still excellent for small jobs.

Polish the shaft with wire wool before using, your hands will be grateful afterwards.

[Tim Downie]

A history of the company who made them.

Thanks. Seaching for "warsop rammer" brought up a lot more links including this little video (for any youngsters wondering what the heck we're on about). ;-)

really don't know why, but I want one. ;-)

Tim

[Adrian]

"Tim Downie" gurgled happily, sounding much like they were saying:

I feel deeply sorry for anybody who could watch that and NOT desperately want one.

[Andy Champ]

For þose who are curious as to why it's in a computer font, it's still used in Icelandic.

Andy

[Andy Champ]

You can feel slightly sorry for me. I don't want one.

On the other hand, I'd love to give it a go!

BTW it seems to me the spark is manually triggered, it isn't automatic. You can see him fire it.

Andy

[Bob Eager]

Reading the historical document, that's right (although later mods allowed it to be semi automatic).

Clever operators could fire it again at a critical point and make it jump higher!

[cj]

Hi Really showing my age now as already stated these IIR were Benjo Whackers or as my Uncle (who operated one ) used to say His 'Banjo' His was a 2stroke petrol machine which unlike a conventional engine had the piston connected to the whacker plate. The cylinder mounted above had a simple carb' and a small fuel tank mounted opposite the handles. To start it you had to bounce the machine as this movement worked a crank which drove a small generator to provide the spark. The trick was to press the drop bar at the right time so as to ignite the fuel at the top of the stroke (memories of flames belching from the carb' and smoke and obscenities from uncle Jim. Later I recall this was automated but memories are at best sketchy after all I was only a kid sneaked into the council yard who was more interested in the steam rollers.

CJ

[Appelation Controlee]

-------------------8><

Absolutely, but it will be regurgitated for ye benefit of my work colleagues tomorrow morning.

[John Rumm]

nightjar Before that, they used a big iron plate on a stick.worked by hand. Probably

I have a mate who swears by his "Elephants foot" as he calls it, for getting better value out of a 6 yard skip!

[nightjar]

and a grumpy old bloke inside.

Colin Bignell

[Mary Fisher]

...

I thought I was the only person in the world who thought like that about things :-)

A JCB is top of the list ...

Mary

[John]

A history of the company who made them.

Ha! British Manufacturing and innovation - I remember it well RIP.

[Bob Mannix]

> A history of the company who made them.

And from the above, how it worked:

How did it work, the inside of the carburetor body was filled with knitted nylon (originally copper)

scouring sponges held in place by a wire mesh grid, with two air tubes from the outside top of the

carburetor body to the inside bottom of the sponges. Two pints of petrol were put in the carburetor body

though the filling plug. To prime the combustion chamber-, half close the air regulator on the side of the

carburetor body then press down until it touches the rubber block several times, the foot spring returns the

body each time, air is pasted down the air tubes into the sponges to mix with the petrol, this mixture then

passes up via the mixture feed tubes and inlet leaf valves past the main poppet valve into the combustion

chamber. By raising the firing lever the main poppet valve would close and the magneto would operate

making a spark at the spark plug in the combustion chamber igniting the mixture and forcing the piston

down, this made the whole rammer jump up into the air by about 17 inches (43 cm). Most of the exhaust

pasted out though the six exhaust holes in the cylinder barrel and the piston being returned by the piston

return spring. On landing the rammer would go past the firing position then scavenging though the outlet

scavenge leaf valves, hit the rubber block and be returned to the firing position by the foot spring

recharging itself with fuel in the combustion chamber. For safety reasons in case the operator did not

release the firing lever the main poppet valve would only be closed for a short dwell time by the trigger

flick over cam while the rammer had time to jump and exhaust. The operator would then raise the firing

lever for the next cycle. Normally 50 to 70 cycles per minute would be obtainable by the rammer operator.

Once the Rammer had made a few jumps the air regulator would be fully opened and then adjusted by

slowly closing it as the petrol was used up. There was also an oil tan}: on the cylinder head with an on/off

tap, to automatically lubricate the rammer directly into the combustion chamber by a ball on a seat held

down by a spring, which would let oil though a small hole in the cylinder head when the rammer jumped.

Our records begin in 1946. Approximate numbers built in brackets by both companies. The original Ben

Johnson Benjo rammer from the 1930's (3,020) with cast in air tubes in carburetor, two side handles one

with firing lever, star wheel ratchet trigger, pull type Wipac magneto on top with oil tank. In 1952 the W

type Warsop Benjo Rammer (900) was introduced with wrap around handlebars with a right hand firing

lever and a top bar for left hand grip, a trigger weight and trigger flick over cam with plunger and return

spring, a rotary B T H magneto and the oil tank became part of the main valve housing. The final version of

this well developed design was the 1955 CB (620) with separate bolt on air tubes going down into the

carburetor and the air regulator moved from the carburetor body to the front of the oil tank on the main

valve housing on the cylinder head. These rammers were available with 7'/z or 9'/z inch footplates. The old

Benjo Rammers were no lightweights the 7 1/2" 215 lbs (97 kilos), the 9 1/2"

250 lbs (113 kilos)

Page 14

[The Natural Philosopher]

That is my recollection also.

[Andy Dingley]

Tracked mini-digger.

A weekend's hire isn't that much. I'm sure you can find a ditch or something that needs a good rooting out.

[Mary Fisher]

NONONO!

I want a BIG digger! Of my own!! And I want to drive it up and down the street and go to Waitrose in it.

Mary