Custom Soft Top

[alistair]

Clyde
You need to take a look at a 405 drophead. In particular at the hood frame which is complex but effective. Not only must it seal properly at the screen and around the door windows but it must fold so that the car still looks good with the hood down. It is critical that the frame is properly adjusted to fit the car and the roof line is right before it is covered - once it is trimmed it is too late. If the frame is right (particularly the wood parts) a competent trimmer will turn out a nice job. I think you could copy the 405 hood frame design and a similar rear seat arrangement should work as the 406 is wider. The S L-J chopped 406 is in his works - I saw it today. Values of one offs are a tricky area but I think that the potential value of your project would be much enhanced as a drophead - providing it looked right.
Alistair Hacking

[406Special]

Alistair,

Is the 405 DHC a 2 seater or 4? Having looked at the car with top up, it has no side glass behind the front doors (for passengers) just the soft top hood. I think it's a good idea to see how it's been done on the 405 and maybe it's a good starting point.

I am intrigued that SL-J has begun his 406 project (DHC). I saw the drawing of his convertible on his office wall back in 1999 and I have no intention of waiting 10 more years to get my car completed, with or without a top. Value-wise, if it is a professional job with good looks, whether it retains the original front screen glass, or loses some space in the rear seat or other modifications, I think it will be more desirable and therfore more valuable. But as they say in real estate, never over invest! I am investing plenty already!

Thanks for everyone's great inputs.

Due to some health issues past 4-5 months I haven't progressed very far anyway, but there again my engine is still not quite finished and Alpine Eagle have been busy with restoration of Indian RR and other stuff. My aim, if all goes well and I get my business back to strength (and me) quite soon, is to make a large push to get as much done during 2009 and try to get it completed 6 months later than originally planned - about April 2010, exactly 50 years after it was made by BCL.

Clyde

[Claude]

Originally Posted by 406Special

Is the 405 DHC a 2 seater or 4? Having looked at the car with top up, it has no side glass behind the front doors (for passengers) just the soft top hood. I think it's a good idea to see how it's been done on the 405 and maybe it's a good starting point.
Clyde

The 405 is a four seater, although the back of the rear seat was custom made after the roof was chopped. The infill fabric in lieu of the rear side window is another compromise... Bristol never quite got the rear window right in any of its cars.. It should have been a crank-down and the popout would not work on a drophead unless Abbott had kept the frame. I would at least have a plastic window sewn in, or even zip open fabric.

The key question is to find out how to get a 405DH frame... you need to find one of 46 cars that is so far gone as not to be worth saving.

Here is your 406 with a 405 drophead top and I repainted the car from yellow to blue.

http://quick.village-town.com/406dh.jpg

On the discussion about strengthening the car, keep in mind, the 405 DH came from a 4 door 405 and it had no roll bar or any other additional strengthening. The body on the car does very little for its structural integrity. Bristols can be driven without a body at all. While the body adds crash protection, it is lightweight aluminium that is riveted, not welded onto the steel frame. The design came from a time when the manufacturer made the chassis and rolling stock, but then turned many of their cars over to a custom body shop - especially in Italy, but also in the UK and USA (Chevy... body by Fisher, for example)

Claude

[alistair]

Clyde
The 405 DHC is best described as a 2+2 with the rear seats more suitable for children. The hoodframe is pivoted in the B post area so the rear seat is narrower than on the saloon to allow room for the hoodframe to fold down each side of the seat. The backrest is moved forward to give space for the hood to fold behind the seat. But the 406 is a bigger car and I think in this case you would be able to retain a rear seat which was large enough for adults. I think it is very unlikely indeed that you would find a 405 DHC hoodframe - and anyway I think dimensions would need to be altered to fit the 406. You would need to find a bare 405 hoodframe from a car currently being restored from which you could copy the design.
An intriguing prospect worth pursuing!
Alistair

[406Special]

Not sure about using the 405 DHC frame for anything more than inspiration or a guide. The good photo doctored by Claude, using one supplied to me for colour reviews by Sam Frost has issues. Firstly the doors of the 406 are longer than the 405 judging by the forward nature of the 405 hood from the side. Also the 406 does not have a quarter light whereas the photo shows that the 405 does (does it?). Having a removable side window that could be secured in place behind the doors so that rear passengers can see out would be useful and merely create more issues for sealing by the hood over the back and top of the windows. On other cars with such an arrangement, these windows roll down into the bodywork.

All interesting. The more one looks at it there seems to be the following choices, each increasing the cost and maybe, just maybe increasing value, aesthetics, enjoyment etc.

1. Do nothing, keep going as originally planned - no extra costs (enough already!)

2. Webasto sun roof with wide large patch above heads to enjoy air and light - probably easiest and simplist conversion, well known and not too expensive - see http://sunroof.webasto.co.uk/product...andia-400.html

3. Simple, removable frame and hood, plastic rear light, no side lights and similar to 405 mechanism - still has issue of front door frames remaining and so not being a frameless design compromised - also issue of petrol tank filler and possible reduction in tank capacity to get a solution - cost may be less than a fixed drop top, but not desirable - me thinks

4. Fixed hood and mechanism with glass or plastic rear light (screen) and removable/fixed side glass (could even be the orignals), leaving the roof section only as fold back. Compromise here is that it does not provide for a frameless convertible or full open top as side glass remains in place with metal frames.

5. Redisgn front and side glass for frameless look and good sealing and a completely folding hood and glass rear light (heated of course). May or may not replace front screen (not really necessary). Would provide a complete convertible experience and look, but still must have issues regarding petrol tank, rear seats etc, resolved.

I intend getting a quote of the Webasto Hollandia 400 to see if that is the easiest and preferred cost option to sunshine motoring without having to plough a new field full of compromises and no doubt lots of extra money.

Clyde

[Hydroglen]

Why a Webasto as opposed to a metal sunroof? A metal one might be
available from a wrecking yard and then fitted to the Bristol. Mercedes
and Jaguar come to mind as possible sources.
I always thought the Webasto looks untidy and home made, with the folds
flapping around like laundry in the breeze.
Dorien

[Claude]

Originally Posted by Hydroglen

Why a Webasto as opposed to a metal sunroof? A metal one might be
available from a wrecking yard and then fitted to the Bristol. Mercedes
and Jaguar come to mind as possible sources.
I always thought the Webasto looks untidy and home made, with the folds
flapping around like laundry in the breeze.
Dorien

Webasto makes a modern sunroof, glass electrical motor with a sliding cover that matches the headliner... exactly like new sunroofs. I had one installed in my 411 in the USA. As I recall it cost about $1,000

[Claude]

1.
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5.
6. Go the Blenheim Speedster route. No top, micro windscreen, tonneau cover. And if you do, shorten the body to 404 size - easy to do as the chassis ends at the rear axle, the boot hanging off the end is entirely surplus, thus you have a good panel beater slice out a hunk.

http://quick.village-town.com/406-2.jpg

Claude

[Max Tone]

Just joined, guys. Great thread!

Speedster route interesting & fun, Claude. If chopping tail, how about grafting on back end of scrap 405 to get fins & 404 look!

Alternatively, chop 18" out of 405 chassis & body to get 404 lookalike. Front doors look to be about same size, rear windows different, but I reckon it would look cute. You'd need to get hold of 404 torsion bars/mounts, or convert to coilovers.

But back to your ragtop, Clyde.........it might be worth looking at Alvis hood & frame, if dimensionally similar; the morphed pic with 405 hood looks just like Alvis. Red Triangle bound to have drawings, if not parts on shelf.

I noticed in early post that you are planning a 'left-field' engine, Clyde; please tell us more!

Merry Xmas all,

Rob