Bayonet Fuel cap

[headdownarseup]

Agreed Keith, even a full on "reproduction" cap will look new as well. There are ways of making these look older than they really are so as to lessen the "turd effect"

With some of these "hard to get" parts, sooner or later there won't be any more second hand parts. And that time is fast approaching. (like you, i've also been looking for some time now for good second hand parts to use, but it would appear they are few and far between)
So, what to do?

I think this is going to be worth it in the end. (perhaps a little pricey maybe) We've already seen how much interest there is just in this alone, what with the marston registry needing them too.
Obviously we need to try and keep things sensible as to how many we think we might need.
It would make sense the more we make, the cheaper things will be.
Even if we said we'll make say 50-100 units (too many or not enough?) only time will tell.

Feelers have been sent out to a couple of small engineering firms that i know.
I shall be going to see one of them in a couple of weeks time, so i'll see what he has to say. (i also know a freind of a freind who's a chrome plater so watch this space as they say)
Keep your fingers crossed...

any more thoughts

jon

[Charles uk]

The air bleed valve wasn't the hard bit, the register has already remanufactured those, identical to the originals.

The press tooling for the 2 brass plates was the thing that stopped us, the inner one required 2 stage tooling to stop the wrinkles & a press insertion tool to lock it into the correct location, take one to bit's & you'll see what I'm talking about.

As for even 50, 50 x £50 = £2500, that you have to spend up front & at no profit you have to sell all of them before you get your money back!

[Horsley-Anarak]

Even if we said we'll make say 50-100 units (too many or not enough?) only time will tell.

jon

That sound good Jon, but even at £25 each, (oil caps cost £16.50) for 50 you will be laying out £1250.00, more realistically £40 pounds each, 50 will cost £2000.00


I will look at the oil caps, have just ordered one. I feel a good look alike may be the best option, an exact reproduction is very possible but may prove to be too expensive.

H-A

P.S.Looks like Charles was thinking along similar lines

[headdownarseup]

Nothing wrong with "lookalikes" in my book.

I'm not even bothered by wrinkles.

Outside appearance i think is more important than trying to replicate an original. As long as it fits and works (and doesn't leak too much) then the teething problems can be worked out as we go along.

jon

[Charles uk]

We made exact copies as this gave us a source for any replacement parts required.

For instance if your air bleed valve has lost the knurled cap from the very top or the chain retaining boss from the very bottom, the first gives you an unusable fuel cap & the second a cap that you could lose completely, 1 clone bleed valve could solve more than 2 owners problems & stop their motor leaking fuel in the boot of the car!

As you only tend to use 1 motor at a time, you only need 1 perfect cap for the motor on the back of your boat, the rest on the rack can live with £16 dust caps.

[JERSEYMAN]

I bought several caps from ceandess before, directly and a little cheaper, great for what they are but they are only chromed steel not brass like the originals, they do rust, if that's what you want then it's not a problem but it's a consideration on a restoration project.

[jerseydave69]

I will purchase one of the caps too! As long as it seals and does the job... That will do for me until , or if ever I get the chance to own one of the "real deals"

[Charles uk]

The Marston registry don't realy need 10 more caps it's just that I purchased the last 10 brass caps from Candess with the intention of remanufacting them into almost identical copies before realising that no one needed to spend that much for a fuel cap when you could buy an SD & break it for spares & get all your money back.

Fortunately quite a few of the Marstons that surface onto the market are beyond sensible economic repair, providing a good source of spare parts, one of the major functions of the register is knowing the location of spare parts, so that we can introduce the chap with 1 Marston & 2 props to the guy with 1 Marston & no prop.

[Keith.P]

A cutaway picture of the air valve setup of the bayonet cap, Sorry for the basic picture, but I think you can work out the basic workings of it.

[Charles uk]

That should explain it Keith, it's just a way to stop fuel leaking out when lain down the back of the car & to let air in when in use.

I can't see a way of simplifing their design, better ask H-A he has some out of the box ideas.

[JERSEYMAN]

The actual article, a correct replica air valve

[JERSEYMAN]

Also, Jerseydave, if you need a cap I can lend you one until the correct cap comes along, they always do, just PM me, I'm a few short myself but only use one engine at a time.

By the way, was that your pretty varnished dinghy with a seagull on the back parked down at La Haule slip this afternoon? Very nice.

[JERSEYMAN]

A stripped down cap, machining the air valve is simple enough but it's going to be a little tricky pressing the brass washers, I still believe that these should be an exact copy otherwise what is the point in all this time and effort.

[Charles uk]

I think your stripped down picture might have answered just about all the questions, thanks Rene.

So if a total of 50 caps is the most cost effective answer, someone will have to go to Candess or whoever manufactures these steel caps & get a price for 40 steel unplated, unassembled caps with 10 extra sets of washers & springs for the register caps, & while they are there, get a look at the final assembly press tool, so a copy can be made for our use.

Then make a fixture to hold the steel caps so that the holes can be drilled on a lathe & cost this, the get a tame CAD draftsman to draw a full set of air bleed drawings so that a cost can be obtained for having 50 CNC turned plus a few extra of the high loss bits, chain retainers, knurled top wheels & dust caps.

Using unplated caps will save the cost of stripping & replating after drilling.

Both of the steel anti splash washers will need drilling to suit the air bleed valve.
All of the knurled top wheels, dust caps & needle valves will need fixtures so that the chrome plating doesn't damage the threads.
The needle valve seat can then be silver soldered onto the bottom anti splash washer then assembled using the copied press tool.

All of this will need to be costed to see if the end result justifies whoever organises it, expenditure.

I'd guesstimate 40 unplated, unassenbled caps @ £12.00 each = £480.00 10 more washers & springs £20.00 fixtures £50.00 holes in caps & splash washers £50.00 air bleed valves @ £25.00 each £1250 drafting costs £50.00 brass bar for air bleed valves £30.00 chrome plating costs @ £5.00 each £250.00 giving someone a total expenditure of circa £2200, that might well take several years to recoup.

[Keith.P]

For a Fuel cap say £65, its still not an unreasonable price.
A high end bike cap would be more than that, than again I have a spare one.