hi everybudy my car is the yellow one on the gallary i finished striping it down today
tuned the frame over and hay presto one of the builkheads on the pass side at the bottum is rusted thrugh andrew is going to post the pics for me
advice on this please allso i have no power in the garage i want to get a gene but i need to know if it will run a welder what size enybody help please
i do hope i can get the frame sorted you boys now moor than me
i live in taunton somerset is there enybody cloose to me? that i can pick there brains
hope to here a reply soone
mikedao@tiscali.co.uk
doc no 4381

You need a big generator to run a welder - at least 2.5KVA for a simple 100 Amp hobby mig.

I am pretty sure that the BType chassis is gas welded - brazed - so replacing a tube will be better with a gas torch and no power needed.

If Mig welding all traces of the braze will need removing before you can weld.

On my live axle B-Type I will be building a new chassis because it will be quicker than trying to repair the existing because of the Brazed nature.

Cheers

Andrew

thank you for reply andy s
wise words it is brazed this is the only rusted though part of the frame but the frame has a slight twist to it not suprised after 30 odd years
i now have to find sumone to braze it for me
do you think i should ad sum extra bracing i will be double skining the frame to try and put sum strengh back into it and stop it twisting
by the way the frame is so light
mikedao@tiscali.co.uk

They are very light indeed - The design is very poor with very little torsional or or longitudinal rigidity for that matter.

The design is heavily borrowed from the Lotus 7 series 2 - which has far less tubes than the S1 7 - story goes that to save weight Chapman cut tubes out of a Series 1 chassis until it failed then put the strength back in with the alloy skinning being stressed to take the load.

The B Type has less tubes than the S2 chassis but no stressed skins - It also has the big no no of putting loads mid beam - The front suspension being a disaster waiting to happen.

This is done all over the chassis with the suspension pick-ups mid way along an unsupported beam.

There are some alloy panels to the front of the car possibly adding in some strength but the rear tub and seating offer no additional strength to the structure. triangulation is very sparse and any engine over about 50HP will rapidly lead to structural failure.

The fact that very few remain on the road is not very surprising.

Worryingly its quite common to find B's with the front chassis tubes that add all the strength to the front suspension and engine bay REMOVED :o to fit more powerful engines :o :o Highly dangerous.

..........he's says with plans to put a high torque 180BHP Alfa engine in one B) ..

Cheers

Andrew

great thanks andy so i will have a 90 bhp sledge
i was thinking of useing the same idea as you boxing the prop in pluse bringing two supports up frome the bottum of the frame ither side of the prop shaft
the week point to me islike you say need to tie the rear through to the frount and try to croosbrase it?
mikedao
ps i will not give up must have a good frame i will go down to sketch sumthing
in the morning scan it and e mail it to you
:rolleyes: