12 replies to this topic

[ga2davt]

Good morning, 

My car used to have a fibre-glass flip front. I'm replacing it with steel. 

 

Does anyone have a view on whether the new steel front end can be bolted on, then it is removable for access? I guess the brace from the inner wing to the front sub frame would need to go back on. 

 

Is this a good idea and would it pass MOT? 

 

thanks 

Philip

[Cooperman]

Not a good idea as the original welded front end is what gives the body it's structural integrity.
A removable front also dramatically reduces the value.
It may affect the MoT as it is a major structural alteration.

[ga2davt]

thanks - i'll weld it back on then. It is not that much work & I have a MIG. 

[Will16]

If you make a steel removable front, it would be no different really to the fibreglass one bolted on. MOT time 'should' be fine. I'm guessing that your car has had the inner wings removed? If you weld the new front on, either replace the inner wings or keep the brace bar in place.

Removable fronts are a good ideas in some respects, but are you going to pull the engine every other month? On the standard engine most jobs can be done with the fixed front.

[ga2davt]

I guess work on the car will be easier and quicker in future anyway...  

 

Now that I've removed the front sub-frame, rear sub-frame, engine and gearbox, I know how these all come off in future. 

None of the bolts will be seized in future as they'll have copperslip & nyloc nuts.

I'll have the right tools, including 6-point sockets (I don't know why the socket sets all seem to have 12-point sockets that round off the heads!!)  a proper breaker bar and special sized sockets. 

 

And spending a few hours getting the car rust proofed will also pay off in maintenance terms.. 

fingers crossed ! 

[Retroman]

You see a lot less removable fronts now.

And very few steel ones, I have done 2 one was the whole front including a panels...not my idea or easy to do, but it did the job, needed 2 to take off and fit.

   The other one I cut down each inner wing where they join the bulkhead, and continued up and over the bonnet channel and down the wings. Flat steel brackets with nuts brazed on underneath wings and 4 allen bolts down each wing. So the innerwings remained welded to the wings and came off with them, Bonnet pins at the bottom where the front panel bolts to the subframe.

Retained some of the strength too.

MOT man never batted an eye.

All front lights on a 7 pin trailer socket...bobs your aunty.

Makes it so much easier to work on.

 

[Cooperman]

That looks as though all the strength given by the full steel bodyshell where the loads are distributed throughout the shell has largely gone.

Looks most unsafe in a frontal impact.

[hunterg30]

Another idea is to change your bonnet hinges to quick release ones ,Far easier to work on the engine

[Retroman]

That looks as though all the strength given by the full steel bodyshell where the loads are distributed throughout the shell has largely gone.

Looks most unsafe in a frontal impact.

The blue one I agree, not my idea but, it used to pass the MOT and RACMSA scrutineering, as did the green one. Its amazing in a shunt how much the stress is spread...I know a racer at the moment porta-powering one out with a crease in the centre tunnel...a big off, not sure it will ever be right.

[Cooperman]

It is designed for the applied loads in a crash case to move into the fully welded structure and be depleted into the entire structure with deformation taking place to absorb the energy over a wide area of structure.

With a removable front this cannot happen as originally intended and it is therefore not as strong or safe. That does not make it a death-trap, just not as strong or protective in a frontal crash case.

On a race car with a full FIA cage and full harness belts it may not be such an issue, but imagine a 3/4 head-on with a large truck and that will exercise the brain and give some reality to the unwiseness (is that a word?) of a flip front of any material.

It will also seriously de-value your classic car by a lot.

[tiger99]

Not to mention possible insurance difficulties! They must be informed of the modification.

 

A bolted front end is an attractive proposition IF you can get the load distribution right, but that would seem to need a lot of stiffners welded in, which would mean extra weight. In the simplest case you would replace each spot weld with a bolt of equal strength. Not practicable! So then you fit some kind of strengthening plates, picking up on 5 or 6 weld positions, with a larger through bolt. Getting a bit more practicable, but still not there...

 

On the other hand, think about all those tiny little bolts (albeit possibly grade 12.9) holding 3 piece split rim wheels together, and have some serious thoughts....

 

I am convinced that a REAL structural design engineer (NOT a keen amateur!) could do this, but at what cost, in terms of fabricated and/or machined parts, and of course weight?

 

Sadly I don't think it is going to happen, but if you are a REAL designer and are SURE that you can do it, we are all waiting with considerable interest to see something genuinely new.

[gazza82]

Anyone watched the Binky series?

[Northernpower]

Anyone watched the Binky series?

Most members on here do and I notice they decided early on to make sure they built in an impact absorbing element to the two front chassis legs. They obviously don't like the idea of a weakened front end.