The Sponsons Thread

[rob565uk]

Sounds like the sponsons are going to be a major challenge to the very end. I have contributed precious little to them bar a handful of spacers, but the Team overall must already have sunk a few hundred hours into them plus lots of blood, sweat and tears. With MKW's contribution also factored in, the total could well be over a thousand hours and many thousands of pounds in cost if everyone was changing for their time, material and MKW's state of the art CNC equipment.

But as the saying goes, do you want it now or do you want it right?

[Richie]

We (the entire team) have invested so much time into these things that as tempting as it would be to simply clash them together (and the outsider would know no different I might add) it will be done at a pace set by Bill and to his usual high standards, be patient folks they will come good in the end

[rob565uk]

We (the entire team) have invested so much time into these things that as tempting as it would be to simply clash them together (and the outsider would know no different I might add) it will be done at a pace set by Bill and to his usual high standards, be patient folks they will come good in the end

There is a saying that familiarity breeds contempt, but whenever I work on any part of K7, I remember that she is an international icon, an outstanding example of British engineering at its best and the most successful WWSR boat of all time, a record unlikely to be beaten. Doing anything other than a proper job is unthinkable, no matter how long it takes.

[Renegadenemo]

Good news... Al and me have been back up to MKW today with a sharp pencil and a slab of plywood and taken a perfect template off one of the planing shoes so we can set up the toast racks at the pointy end to within a squillimetre of a smoot.

[Renegadenemo]

You get three bulkheads at the pointy end set out to the Nth nano-smoot, then a gap, then another seven uber-accurate ones, then another gap then a final accurate piece right at the blunt end.
What you do next is squish six chunks of guesswork into the front gap and seven into the back onto which the spars eventually attach. Somewhere in among that lot we managed to grow the sponson an eighth of an inch too wide in the guessed bits. Now considering that MKW's machines didn't lose the plot by an eighth of an inch we discovered the problem when sticking a sponson to a planing wedge. Ironically, there's good photographic evidence to suggest that the samlesbury boys had similar troubles and bodged a fix but it's far from conclusive so we're doing a proper fix.

[Richie]

98998d3759c5153bf5c2cb79dfd04733_zps5d4de6e3.jpg

"Sponson datum's.......they're not to be messed with, Mike messed with the datum's and look what they did to him !"

[Renegadenemo]

Cracking shot of Mike there... We got the sponsons back under control today. Phew!

[Dominic Owen]

I've a sneaky feeling I know exactly what the answer to this is going to be but, just out of curiosity, why does the rearmost bulkhead on one sponson have two round lightening holes and the other a single large oval one? My money is on something along the lines of: "No idea, they weren't drawn that way but that's how the originals were made".

[Mark Elvin]

Those planing shoes look very nice, what's the finished weight vs billet weight like?

[Renegadenemo]

Those planing shoes look very nice, what's the finished weight vs billet weight like?

I'll have to re-check the exact figures because the ones I have are prior to a change made to the CAD model after we realised we'd initially worked to an earlier drawing but the billets are a shade over 350kg and the finished parts are a shade under 49kg - that's a shedload of swarf!