19 replies to this topic

[mariner]

I have just been doing the Saturday help around the house thing of making the beds. This requires me to put the duvet into the duvet cover, a task I am congitally incapalbe of doing quickly.

As I struggled with the duvet I began wondering how on earth did they get those long thin fuel bladders into the long, thin monocoque boxes of old?

I can see it is easier with a modern car becuse the fuel cell is a single central bag but back in the 1970,s the fuel cells were fitted down into a long thin side monocoque box and usually there were only two small apertures to keep the strength up. I have never had to do this on a car so does anybody know if there was some special trick like using compressed air?

[McGuire]

Baby powder.

[John Brundage]

The old bladders were alot more pliable and easier to work with than the ones made today. And yes--baby powder is the trick.

[PeterElleray]

Originally posted by John Brundage
The old bladders were alot more pliable and easier to work with than the ones made today. And yes--baby powder is the trick.

also quite common to vacuum out the bags using the office 'hoover' so as to reduce their physical bulk. there is a nice story in mike lawrence's march book where this had the unexpected byproduct of sucking fuel vapour into the hoover, which converted it into a 'do-it-yourself' gas turbine and resulted in an indoor rocket attack on the build shop which destroyed the vacuum cleaner...

[MikRo]

Originally posted by PeterElleray


also quite common to vacuum out the bags using the office 'hoover' so as to reduce their physical bulk. there is a nice story in mike lawrence's march book where this had the unexpected byproduct of sucking fuel vapour into the hoover, which converted it into a 'do-it-yourself' gas turbine and resulted in an indoor rocket attack on the build shop which destroyed the vacuum cleaner...

Yes after that experience we made some tubes and an air line blowing away from the tank to evacute them,
We also used a lot of broom handles to get them right into the corners

Mike

[eurocardoc]

The problem at March was that most cars in the assembly shop were new kits and so no problem using the Hoover, but if the tank was being reused after a tub repair those fumes were still in it, hence the explosions!
amused the workforce.....

Much like the silent giggling following the familiar pop and hissing as another fire system was live tested in same area!

Taping over the rivets often was more demanding than the bladder install, the baby powder made that easier for sure, still use it today for fuel cells and inner tubes.

[Doug Nye]

I suspect there's inherent confusion in this thread's origination - in-period bag-type fuel bags, as made by Marston-Excelsior and Goodyear, were literally empty bladders which - as already described - were more pliable and certainly more collapsible than modern fuel cells which normally include anti-surge foam filling - I believe a Goodyear fuel cell innovation (?). I remember Team Lotus mechanics cursing the Type 72 in particular for being a swine of a tub to fit the tanks into, and from my own experience the Type 49 wasn't much better - especially if (as Win Percy once said of me) you've got arms like Pop-Eye...

Despite best efforts to tape or pad the edges of the access holes - which to preserve rigidity within the monocoque tubs were necessarily small - it was inevitable that the tank-fitting process would leave the fitter grazed, scratched and cut. In fact there would have been so much skin tissue left in any of those old tubs that when DNA clone recreation becomes a reality half the mechanics in F1 could reappear. What a thought...

DCN

[fines]

Another case of European technology lagging behind...;) Foam-filled fuel cells were invented in the mid-sixties, by Firestone I think.

[elansprint72]

KY?

[eurocardoc]

In the early 70s, the March cars had a fuel bladder in the side of the tub, both for F2 cars. You inserted by removing the end cap and sliding the cell in, if it was collapsed via a vacuum, it went in easier. They did not have the more familiar oval bolt rings.

[John Brundage]

Doug is quite right about leaving skin. Having lost abit putting a new cell in through the oval in a Lola 332 is no fun. Right now I am removing it to re-rivet the bottom of the tub in a couple areas. They don't come out easy either.

[HistoricMustang]

Originally posted by fines
Another case of European technology lagging behind...;) Foam-filled fuel cells were invented in the mid-sixties, by Firestone I think.

I am not sure Europe lagged behind. Perhaps developed and then did not improve.

Henry

[GD66]

Mariner, it's my understanding that initially the first bladders were installed by the same gynaecologist who decorated his hallway through his letter slot....

[h4887]

Originally posted by McGuire
Baby powder.

They make powder out of babies?

[mariner]

Thank you for the answers,I nevr thought of baby powder. I guessed it must be a fairly painful process looking at the size and sharp edges of the acess holes in the older cars. I guess the benefit of the later "atl style" bags is that the access hole can be much larger as it is closed off with a solid plate and multiple bolts which stiffen the aperture.

I presume that the very first bag tanks were on the Lotus 25 as previous designs did not need bags?

BTW I can remember ( I am that old) the press handouts for the Lotus 25 which claimed that a patent had been applied for the monocoque idea by Lotus/Chapman. Was such a patent ever applied for and is so was it granted?

I sort of assume there was no grant of patent but if it was applied for and rejected then the Patent office would have had indicated the "prior art" etc. which would be interestingg historically.

[McGuire]

Originally posted by h4887


They make powder out of babies?

Also baby oil. Once the pressing phase is completed the husks are ground into a fine, delicate powder.

[McGuire]

Originally posted by elansprint72
KY?

There was a mechanic who used a silicone lubricant from a big white squeeze tube, I believe the brand was Sil-Glide. It was clear and approximately the consistency of snot. He would butter up the entire bladder and container with the stuff, every square mm. The bladder would go in and out really slick but God What a Mess. Attracted plenty of track dirt and grit as well. I remember feeling grateful when he was compelled to move on. No names as he is still around.

[Barry Boor]

Look at this picture:


If you look at the bottom left and opposite, below the gear change rod, you can just see the access panels through which we fed the bag tanks.

The anti-slosh foam was fed into the tank through this panel, in pieces of the exact cross-section of the tank and about 100 mm wide. They could be fed along to the farthest points and then succeeding pieces added until the tank was completely filled.

The remarkable thing about that foam was how little space it took up. I remember Peter cutting a piece to fit exactly in a saucepan. He filled the saucepan to the brim with water, then fed the foam in. The amount of water that overflowed was no more than an eggcup full.

[Tony Matthews]

Not always easy to remove, even through a relatively large hole!

[Peter Leversedge]

I only ever removed and refitted a bladder in a sprint car tail tank and that was a pain in the ..............