Blue Heeler wrote:
> jackbadger56 wrote:
>
>> Watched this last night for first time. Two teams were let loose in a
>> scrapyard to gather whatever they needed to build a fire boat each.
>> It had to float, move across a lake, put out a raging fire and
>> return. Awesome stuff! One team modified an old Land Rover which
>> they cut in half and connected a (fabricated from scratch) water
>> pump, the other team cut the roof off a van for the hull, got an
>> engine from an old Fiesta running to power their water pump made
>> from a short motor. Tonight they have to build a dragster for a
>> quarter mile challenge, all from junkyard bits!
>> Interesting stuff ;-)
>
> It is contrived - but I agree fascinating.
>
> In fact, I'll quietly admit that I'm planning to buy the DVD when I
> find it to get the episodes I've missed.
>
> I rather do wish that they had shown just a few more details of how
> they modified the engine into a pump, they showed it with its head off
> and then a drawing of some pipes and one way valves, but never of the
> finished article or its intermediate construction.
There wasn't much to show - they just attached a simple head to the top of
the block that grouped the pistons in pairs with a pipe going to each
pair.
Each pipe went to a T with non-return valves on each side of the T.
> Likewise the "jet" pump the other team made - details of it's drive
> and the suction and outlet arrangements were omitted.
It wasn't a jet pump (of the Hamilton variety) rather it was a very simple
open-impellor centrifugal pump which appeared to work bloody well compared
to the other effort, and kind of showed the benefit of being able to
calculate theoretical performance beforehand such that they could be
confident of it doing what they expected. Since there's no way it'd
self-prime, I suspect the entire pump was submerged.
> I smell a TV production "rat".
Yup, they clearly make sure each team takes a different approach - in this
case positive displacement versus centrifugal pump - they always make sure
a
suitable vehicle/engine/part is somewhere in the yard - the dragster
episode
had the motorbike team "finding" 4 pristine pillowblock bearings which
just
happened to fit their rear axle shaft exactly. Furthermore, a hell of a
lot
seems to happen in the last hour/pre-race "tweaking" time, but it does
mean
both machines are finished, safe and they can have a decent competion at
the
end.
So, yeah, a lot of contrivance and cheating, and it's probably a rip-off
of
another show, but it's well done.
|
