Late July 2021 and the Pathfinder build project resumes with cooler weather.
Tonight,(July) as i write, the centerboard is sitting in all of it’s shiny black glory with it’s last of 3 coats of epoxy resin and graphite powder on and with it’s actual pivot hole bored – but only after a lot of frustration ; more on that later. I’m also about to ‘close the case’ – the centerboard case that is, this week and after similar frustrating problems mainly with drilling straight holes through lots of materials all at once so….
On the bench.
The centerboard will soon be the first fully complete component of the whole boat and i hope quickly followed by the complete board and case assembly as i should be able to do the last few jobs on the case in the next few days. Right now i’m waiting for the pivot pin which isn’t going to be what i anticipated using but in the end seemed the most sensible option. Once iv’e made sure that the board can swing properly inside the case and ‘drop’ properly ( i have to do it all sideways at the moment) i can glue both halves together and pass the big through bolts right through the case sides and spacers : that’s going to be a fair heavy unit once done. I’ll also have to find a way of temporarily securing the board in the case so that it doesn’t try and drop while i’m fitting the whole assembly into the boat. Once that’s ready to go i drop (carefully lower) the entire assembly into it’s slot and start building the boat from the middle outwards.
Centerboard before coating with epoxy and graphite, centerboard logs split for frame no 4 .
Wonky holes and drill guides.
In a big push and long working day earlier in the week something went badly wrong with my drilling of the bore for the centerboard pivot – i don’t know how or why it went so wrong but i went from having a guide/pilot hole seemingly straight and square through both sides of the case and the board and then ended up with the main bore so far out that it wasn’t even in the same post code !. I do think now that part of it was that i drilled the first part of the big hole (25mm) with that side of the case clamped to my upsy-downsy tilt table on the bench drill….i did work out only afterwards that the tilt table looked square but had sagged to one side to enough degrees to throw the whole ‘hole’ out when it finally came through the last part some 200mm later : as i worked out later , something like a 5-6% error on the table. After that i spent some time trying to work out why the tilt table doesn’t lock at zero (square) but can still tilt a few degrees.
Having done that day right at the end of a hot and tiring day where everything seemed to want to troll me i was thoroughly fed up that night because i’d tried so hard to get it right first time. It took another day to re-cast the epoxy bores, a chat with my mate in NZ and a lot more planning to get it right second time around. My solution was to support the first case side on a fixed table built up under the drill head with the tilt table swung out of the way – because the drill only has a working range of about 90mm i then had to slowly pack the piece up and up to let the drill work through the whole case so that i could get that continuous guide hole for the pivot.
My mate ‘Big Al’ – former F1 and superyacht engineer also told me about doing the job with a built up stage and also suggested making a simple drill guide for the next few jobs – drilling for the case side thru bolts and the board itself. Why i didn’t think of that myself i don’t know but it was a matter of a quarter hour’s work to make a drill guide out of a solid chunk of hard Sapele…..a 10mm guide at one end and the big 25mm hole at t’other. While i was at it i drilled a couple of holes at both ends of the guide so that i could screw the guide solidly to the workpiece and have at it for the main hole. The actual bores then only took as long as slowly pushing the bigger drills through the various parts – in the case of the big and long bores for the pivot i ended up using 3 different drill bits with the big 25mm (allegedly) bit only doing the last few side millimetres of the hole. The allegedly is because i was just about to order up a custom made 25mm pin in 316 stainless steel, drilled right through for it’s bolt…..and then thought to check the size of the bore and then the drill. The actual hole only came out at 24.37 mm so my solution to the pivot isn’t going to be an expensive custom made pivot but a gert big (M24) bolt in A4 stainless steel…….off the shelf with bolts and washers to match. That’ll be the largest and most expensive bolt iv’e ever bought but a lot less than a custom made part.
Bright, black and shiny ; the fully graphite and epoxy coated board with the pivot bolt in and the sides dry-closed.
It seems as though iv’e been working on the board or the case for weeks on end and not seeing any change except for another sanding down and more coats of epoxy and graphite powder. The first coat of the epoxy-graphite mix was awful , it came out distinctly rough with little sharp ‘nubbins’ that i thought were bubbles but were in fact small graphite spikes : i found out later that i’d used far too much graphite powder so once i’d sanded the board back i re-coated it twice with a thinner mix. I must say that it looked quite smart.
About a week ago, as i write, i finally had all of the parts either bought in or made – it took some time for the fasteners company to source the 250mm M24 bolt in A4 stainless steel but that finally arrived with a variety of washers and a huge Nyloc nut (eventually not used) so in a morning’s work i was able to do the final fettle an closed the case side with glue and screws. The finished assembly is actually quite heavy and difficult to handle in and out of it’s slot so i got my next door neighbor on the job and with his assistance we did a couple of dry in and out’s and then with me making the glue and him ‘buttering’ the pieces we finally settled the whole assembly into the slot. The worst part of the job was crawling underneath and laying on my back while i drove the long screws in all set in epoxy….hard going because i used 14 gauge screws and as long as possible….extremely useful though to have an assistant to pass me the screws as the epoxy started to gel.
Centerboard set in place, the yellow cord is a temporary lacing to keep the board in it’s raised position.
Getting the centerboard and case into position is a huge relief because it means that i can now start building the core of the boat starting with attaching the middle frames onto the bottom board and across both ends of the board case. In a couple of weeks time i think the project will look very different as then the boat will suddenly take on a 3 dimensional shape rather than being a nearly flat surface and a stack of flat-pack parts in the shed.
I thought about this – whether or not to put this in or not so…….
The delays in the project are partially because of making one exhausting road trip (400 miles in one day) to go visit my very elderly and frail mother who was in a care home, coming home i knew that i was going to have to push some buttons and get palliative care involved with her end of life management. I’m being pretty cool and dispassionate about it now but the care home were being a bit slack and passive about her pain management and by profession i’m not only a retired RGN but also a former specialist nurse in pain control so i could see what needed to be done. Long story short but my mum died about 2 weeks ago……as i write and naturally it’s taken some time and application of effort to take up the project again but it does get my mind working again .
The second thing that happened is that i suddenly developed a nasty finger infection which the nurse practitioner at our local hospital thought was a simple Paronychia but which my partner’s boss, also an A&E practitioner thought could have been a tendon sheath infection. I’ll spare the gory details but for a small injury it was staggeringly painful, weirdly so as it should have been amenable to basic painkillers and wasn’t. I ended up having 3 different courses of antibiotics and a heavier duty analgesic plus the usual stuff regularly. I think it’s on the mend now as all of the skin has peeled off in great chunks leaving a tender fingertip. Very un-funny but i was trying to do some light sanding yesterday and somehow i managed to lose grip on the sanding block and ended up driving that finger straight into the side of the case…..i didn’t actually pass out but i felt sick for a few minutes ……may even said a few bad words.
On the project now i’m doing the work but it’s taking all of my effort to get out there and most mornings i just sit out there with the plans and a big mug of coffee while i work out what to do, luckily at this stage i’m doing mostly the same thing over and over (fitting frames) so once i worked out my work sequence i haven’t had much problem solving to do.