Two down 3 to go, except the next 3 are actually one big one so 1 to go? But who’s counting?
Before I can glass the top steps in I have a bit of work correcting them so that they wont fall apart on me. I have to remove the overhang (that was originally going to house the LED rope light) and glass the top of each step to the riser below. Then I have to somehow put the port steps and lid back together (the lid was cut out of the steps in order to show off the LED rope light at a trade show a few years back, I even faired and painted it) because over the years the step set minus the door has started to come apart, it was this that prompted me to realise that not having tape on both sides of each step join would eventually fail.
Once the front edge overhangs are taken off the steps and the external glass tape added, I will re fair them on the table in the same way I did for the second bottom step detailed below, and then there are a few installations into the outboard well that will be easier to do before the steps go in and then I can finally glass in the last 3 steps leaving just the trim on the side and top step to complete the step sets and the construction phase of the build will finally be over (with the exception of some rigging pads, ply pads that the rigging will be attached to – winches, clutches, turn blocks, sheeting points, etc. to be glassed on and faired in). Then its bogging and sanding repeat repeat repeat for a few months, probably 6.
So to bring you up to date with what I have done this past week or so (it does not seem like much but its about 6 or 8 visits to the shed. Many of which required a wait until the next day to perform the next step due to having to wait for filler or bog to set. I had glassed the inside of the steps with kerfs to set the curve on the front (riser) which started as a flat panel then was curved to the shape that the step top was cut to. The shape was determined a long time ago when the steps were originally planned. To determine that shape I decided on a step tread depth (front edge to the riser of the next step) at the middle and about the same amount at the outboard side, then ran a curved batten around to strike a fair shape, ran a pencil line along the batten and cut to that shape. It also has to be visually pleasing so that all of the various step profiles form one set of steps that both work and look pleasing. From memory (it was a while ago now) the middle step which is at the bridgedeck level was the first shape decided on, because it has a duel purpose, you can walk around the corner to the duckboard or continue up the steps onto the deck, so that step needed to be shaped to perform that duel task then all the rest of the steps were shaped to match/suit.
With the inside of the step kerfs and join front to top glassed on the inside, I decored the exposed edge of balsa of the step tread (outside top of the step) and back filled it. Where ever a balsa edge is glassed over to form a 90 degree join in a place of high wear or likelihood of impacts the edge must be decored and back filled. The balsa alone does not have enough compression strength to resist deformation so on an edge of a step where things are likely to clang up them or bang into them or otherwise cop a bit of a beating, it is essential that the substrate to the glass and bog be solid. It is also quite difficult to get a consistent radius curved edge with raw balsa and easier with set filler.
So once the filler is set, the edge is curved then glassed and bogged. You could use a router to shape the curve but I find it just as easy to use a short flat sanding board. As mentioned, bogging and fairing is much easier on a table than on the boat. Alas, there are only small sections that will remain fair because once on the boat another tape is required to glass it in but at least that will be below or close to below the bog height and fair back out again. In fact, I fair to the edge of the panel then grind off the bog where the next tapes will go. I usually apply the bog over wet tapes so as to get a chemical bond at least in parts.
As for fairing, there really isnt much too it, mostly elbow grease. I secured the panels to the bench and just sanded until it was fair. Each one took about an hour. The conventional wisdom is that you really cant use power tools for fairing but the truth is, if used sparingly and correctly you can get away with some powered sanding to start with but you will definitely need to finish with a board. The important thing is to keep the sander moving, if you dont, you dig holes that will need re filling. But ideally, you really shouldnt use them for anything more than taking the very top off and besides, if using 40 grit paper on a sanding board, you surprisingly remove more material with a sanding board than an orbital sander. I like to push the sanding board at 45 degrees to the area being sanded so that the board moves across it as well as along it, then back the other way at 45 degrees opposed so that the sanding overlaps, this ensures you dont dig holes with the sanding board either. And you simply keep going until you hit the top of the highest tape or the panel is fair, whichever comes first. If you hit the tape and the panel is not yet fair, you will need to fill the lows and go again when it sets until you eventually have a fair panel. The tapes are the high points and you cant sand through them.
In cases where the panel will be glassed back onto the boat and therefore need to be faired again anyway, you can fair as much as you like but I guess the fairer it is to start with the less sanding you will do later at odd angles or precariously perched or in areas difficult to get to. When I removed the bog where the next tapes will go I could see how deep the bog layer was, and it is deep enough that the next tapes will be below the height of the existing bog, so once glassed in I will have a level to which the next bog will be applied. The square below showed me 3 things, that the step riser was square to the tread, that the front was fair enough, there is a small gap about 1/4 of the way down but it is less than half a millimetre deep, and finally it shows that the depth of the bog removed as seen at the bottom of the pic is deeper than the thickness of a fibreglass tape, which is about a millimetre, my bog depth is about 2mm so with a tape in another millimetre of bog will cover the next tape. Of course you are treading a fine line between the weight of the bog and the fairness of the panel, as you want to get as much of the bog off as you can without going out of fair so as to keep the weight of the boat down. If weight was not a consideration I guess you would just bury every join in bog and sand until fair regardless.
Then just to finish on the fairing exercise I ran a batten around the front of the step again to see how fair the curved edge was along the curve as opposed to the fairness top to bottom that the straight edge of the square showed. The curve is very fair along nearly the entire length except the edge gap visible at the bottom of the next pic, however 2 things, first the edge of the panel has had the filler removed ready for next tape and also it is at the end of the panel that will be cut off as it overhangs over the edge of the inside of the hull, so it should mean that if anything maybe 20mm of the panel may need some filler to fill that gap, but I doubt it. The batten appears in the pic to bend to the left about 2/3 of the way down, but that is an optical illusion created by the perspective shift of the camera lens.
With the panels faired and ready to be glassed into the boat, there was a little more fitting (grinding and sanding of bits), and some preparation below it first. Once these steps go in, they create more flotation chambers below that are permanently sealed. I have often said that building the boat is a series of problem solving exercises that impede progress until the solution is discovered. I had 2 problems that one solution solved. First I was a little worried that I did not have the webs under the second step that are under the first step. This is not a critical issue, after all, there wont be any webs under the steps above, in fact there is a huge unsupported area below the next steps but I am sure that will also be a problem looking for a solution. The other issue was that in behind the outboard well is going to be a sealed section but it houses the rudder tube, so I had to figure out a way to maintain access to the rudder but maintain the seal of that chamber. So my solution was a 4 sided box open in front and above so therefore sealed everywhere else, glassed over the rudder tube. This box allows me to remove the stainless steel tiller from the rudder stock without lowering the rudder, it gives access to it all from outside the boat when the outboard lid is open, it creates a sump that drains into the rudder shaft which does not seal out sea water (by design, it keeps the rudder bearing water lubricated) so will provide some top bearing lubrication,it seals the chambers below and behind it under the step and finally provides some structural support similar to a web below the second step.
Next I white coated the chambers on the inboard side of each hull, I didnt bother with the outboard side. The reason, the inboard chambers have the underwater lights cut into them, and whilst I anticipate a watertight seal of the lights into the hulls, should they leak, the chamber has an extra layer of sealing of epoxy. Also, the port hull light is an expensive one, the starboard a cheapy, and I had intended to seal them in and if they fail, thats it for underwater lights but Jo convinced me to put in access to the expensive one so that if it fails I can replace it with…..another expensive one that might also fail. Makes sense I guess. So I cut an inspection access port into the bulkhead. At the very least I can check the chamber for water ingress. As for getting the light out…..maybe a small child might be…..never mind. I will solve that problem should it occur. As will all cutouts, I decored the edge of the port hole before I can seal the inspection port in, this is of course to seal the balsa core of the bulkhead from any water ingress. Core integrity is one of the highest priorities second only to hull integrity I guess.
I found another great tool for de-coring duflex balsa panels. Ironically, I am down to the last of the panels needing a de-core. I usually use a router with a bit in it a little like a saw blade that runs square to the shaft, it can be set just above the skin and its cut to the shaft is about 10mm, you run the blade along the inside of each skin, then flick the balsa in between out with a screwdriver or chisel. I dont like routers. They scream at a million rpm’s and one slip and you have cut a hole in the skin, no second chances. But is works very well. I only needed to de-core the inspection port hole to back fill and setting up the router for such a little job annoyed me. So I tried the multitool with the round saw blade. It works a treat and is very benign and it would take quite an effort to cut through the skin, it cuts the balsa easily and will cut the skin if that is your intention but it wont just tear in if you slip. It is one of the tools I would recommend to anyone setting out. It is fantastic for cutting in hard to get to places.
For those unfamiliar with the multitool, they have been around for about 20 years or more but the inventing company, Fein, charged about $600 for them a decade ago. I first saw one at another Schionning builder’s place. He showed it to me and told me to grab the blade of the machine while turned on. I declined so he did it. It cannot cut you. It just vibrates you hand. In fact, the multi in multitool is because it is also a corner sander when fitted with a sanding head, a chisel when fitted with another blade, a paint scraper etc…and it all works on the vibration it creates. But the genius’s that created it, seemed to forget to renew (if they ever actually applied for) the patent. And now every Chinese tool factory makes one. I got mine at Aldi for $40! Fein’s loss is our gain, because there was no way I was ever going to pay half a boat unit for one! (A boat unit is $1000, many builders prefer to talk in boat units rather than thousands, it is less depressing!) (Too many sentences ending in !)
Once the white coat had set I sealed the underwater lights into the holes and the inspection port in leaving just the step to go on to seal it all up and finish this section of the build. The wire for the light will be lead up through a pvc pipe and into the outboard well, and into the end of the pipe I will silicone seal the wire so that water cannot get into the pipe and through to the sealed well on the other side. And because water does not flow up hill but wires can be threaded uphill, I will slant that pipe uphill). If water does get in, I want to be sure it has come in through the hull not from inside the boat. Let me rephrase. If I find water, I will know I have a seal leak around the light and that it needs a repair at the next dry out.
One final dry fit to ensure that the step sits snug and level without needing to be coerced into place and I was ready to glue and glass that step down. Ideally you want tapes on both the outside and the inside. But inside is a sealed compartment. I needed to build up the height of the bulkhead it sits on by 40mm on the port side and 50mm on starboard (I know! I dont know why, the riser height is the same so go figure) and had intended to fill that gap last but decided instead that it made no difference for that gap to be 40mm or 100mm, and 40mm is just too narrow to squeeze an arm through to run a glass tape inside the steps so I just cut the gap out to 100mm and will glass a piece back in later to close it all up and seal the space. After that, I have to glass a 25mm plywood table onto the bulkhead for the hydraulic ram mount that will be glassed right above the temporary arm holes. And for those that have never tried something like this, glassing with one hand is near impossible. That I managed it including one upside down, and by feel alone astounded me. Having said that, it is perhaps a good thing the tapes are inside sealed compartments. They were pretty ugly!
When the next steps go on, the rudder tiller box you see in the pic below, will sit just inside the outboard well lid, so will be very easy to access with the lid open, and access to the hydraulic ram will also be very easy from kneeling on that step, handy for bleeding or other adjustments, and of course when closed the lid will conceal that recess. At the moment the outboard door just covers the opening. You can see in the pic below right, the step overhang I have to remove from the step sets to glass the outside to get them to proper strength before glassing them into the boat.
Still a bit of trimming of the overhang on the inboard hull edge then a tape along there and the step is pretty much done. The next set of steps might be a couple more weeks before they go in. I am in 2 minds now if I should make the outboard lid a step smaller. It currently spans 3 steps but I am thinking now that I could make it just span 2 so that it would finish where the level is in the 2 pics above, which is on the bridgedeck level. That’s a long way off the water, so is more protected from following sea wash over, and of course the smaller the door the less pressure or weight on it to support. A big door looks like it would make outboard servicing really easy though. So I will give it more thought for a while as I do the work inside the outboard well that I want to have done before the final steps go in.
James Thorpe
Thanks Paul, I’ve just caught up with your last few entries. I really enjoy reading them – you put a lot of effort into the blog (and the boat!).
Cheers, James.