More Planks

Today, I continued on with planking, having completed my keel mold and awaiting delivery of some melting equipment - more of which later.

My dilemma is to decide which boards to cut my next planks from. In the specifications there are one set of boards scarfed at a slight angle to accommodate a more "banana" shaped plank.  However, there is no reference as to which planks these boards are for, so I am going to cut them out of the same plank as I used for the garboards.  My wife casually remarked that the angled planks are probably for the mid section of the boat - she obviously has a better 3D mind than me and I suspect she is right!

[EDIT Jan 2013- I since found a reference in the plans as to which strakes are made from the angled boards - answer: nos 3 and 4.  Once again it proves to me that all the information is in the plans, you just have to search diligently!  However, I only made this discovery when fitting the final sheer strake.....but when I re-examined how I had used the boards, to me pleasant surprise, I had applied them to nos 3 & 4!!]

So I have just spiled the patterns boards and laid them onto the planking stock.  Marked out the various marks but there seems to be an ugly wobble in the lower line - I had a similar issue with the garboard around the same station - #6...I'm wondering if I have some issue with the marks at this mold.

It's dark outside, so I will go at it again in the morning and see if I can figure out what's going on.

12 Hours later.......

This morning, I eased some of the hard spots and with the assistance of Brian, who I recently discovered lives near me and also is building a wooden boat, we managed to fair out some decent lines.  Unfortunately, one of my battens was too thin so when I routed the final edge the batten bent inwards leaving depressions between the nailed points.  We had to re-trim the edge to take these high spots out, which meant the lap is more like 1 1/16th rather than 1 3/16ths - I can't imagine it will be too must of an issue.  So tomorrow, I will make a new Douglas Fir batten out of wider stock to make sure I don't have further incidents of the batten moving while routing the plank's edges.

Also, I am going to remake my spiling pattern.  It is made from ordinary 1/4" ply, which arrived from the store with a wicked warp  - delivered in my absence!  I used the warp as I thought to my advantage, to follow the curve of the hull, but I am not at all sure that this is working out correctly, so I am going to use some of my sapele 1/4" ply for this (once I have checked to make sure it's not all required for other parts of the boat.  

36 hrs later....

Finally manged to fit the board ready for epoxying to the garboard.  The Dory Gains were really troublesome, as they didn't seem to want to mate to each other.  Had to do a lot of fiddlying and fudging to get anything close to a fit, and still I reckon I will be relying on the magic properties of epoxy.  The angles of each Dory are the same, but I subsequently realised that I should have also calculated for the angle delta between the two planks to get the Dory gains to fit.  It is not at all clear to me how to get these cut without a lot of incremental guesswork.  Also I note the that the plank does not sit on the frames at stations 2 & 4 but rather kisses the frames at the lower side (sheer-side) of the plank .  So I am now wondering why I bothered beveling the cheeks which were attached to the plywood frames if the planks are not going to fit snug against them.

Station 2 - the gap is obviously going to be quite large, but should I fill it in or leave it?  Does the plank need to be screwed to the frame and if so where - probably at the laps.

Same issue at Station 4 where the frame and the plank is separated by a large gap.  I presume the gap itself is not an issue , although the cheek on the frame looks  strange. 

Here is a short video which shoes the challenge I've had trying to get the Dory gains to line up.

So John Brooks came to the rescue and wrote me an email of explanation....:-

"Dory gain is same width as lap. You will also make a dory gain on the underside of the next plank. Measure the angle between the landing for the next plank on the transom and the dory gain on the garboard, cut this angle on the underside of plank #2 where it meets the garboard, then make the dory gain to this angle. On the garboard, make the lap bevel flow into the dory gain"

Thanks John for the assistance,  it's beginning to makes sense now to me and by the time I get to the sheer plank, I may have a passable example..

Finally planks 3 & 4 are affixed.  I spent some time rechecking the offsets and made a large dividers to check for symmetry,  It transpires that the jig is perfectly aligned and level, and the molds are symmetrical.

I concluded that the difficulty I had fitting the last planks to their marks on the molds was due my spiling - relying on a warped spiling pattern.  So I decided to remake the spiling board out of 9mm larch planks.  So far they seem to pick up a fairer curve than the original 4mm cheap plywood.   Here are the old planks which composed the spiling pattern - you can clearly see the warp in the boards.

Here is the new spiling patter in action - I am hopeful for more precise outcomes.

 
The bow of the boat is hard pressed up against the inner wall of my garage, so it's difficult to sight the lines from the bow - my only opportunity is to take a photo holding the camera against the wall!   It will be interesting to see the boat when I take her out of the garage for the first time...

Notice where the blue F Clamp is holding the plank against the #2 mold - there is quite a large gap here - as if the mold is too narrow but checked the measurement and it seem fine.  So I'm wondering if that is as it should be or if I have not trimmed the inner stem sufficiently causing it to set the plank at a wider curve...

The transom is beginning to take shape.  The dorys look fine (at least to my eye).

Keel Mold

Having run to a standstill when a supplier of fasteners told me one month after ordering the screws that his supplier's factory was demolished..(yeh likely story Dave) I decided to start building the mold for my keel.

Using JB's plans for the keel, I ordered some pine from a local supplier, somewhat thicker than specified, in the expectation that it will be strong enough to contain the lead without having to bury it the ground, as John specifies. I want to be able to move the mold when pouring the lead - using steel tubing as rollers underneath the mold.

I read lots of threads on forums about lead keel pouring - and various solutions including coating the inside of the mold with water glass - but I'm going with a wood fire in a barrel enclosing the crucible.

I had been storing some gas cylinders which I planed to use as a crucible for lead smelting, I meanwhile came across a local company who was advertising some steel barrels for free - when I arrived to collect them he also had some old oxy-acetylene bottles which were also for the taking.  So when home with my new crucible, removed to valve to vent the bottle - it was marked 1970 - so it was old but still had the smell of acetone emanating from it.  Five hours later we finally managed to extricate the solid mass of firebrick from within...

Next, to deciphering the plan.  At first it seemed a cryptic document, but I persevered and finally made sense of the plans.  No doubt a seasoned boat builder would grasp it in an instant, but to add to the complexity, you need to make a special pattern ruler which accounts for the lead shrinking.  

150 screws later, I have a mold ready for pouring...time will tell how successful it is..

Having used spacers to define to mold profile, I had to cut them out as the top of teh mold is narrower that the base..

 Copious use of clamps were used to bend the 1 1/2" timbers to shape.  Plenty of screws where used to keep them in shape and so far it seems robust.

 I used a large coach bolt at this end to keep the timbers together.

 The finished mold, including vent for gasses to escape the enclosed portion of the mold, as specified by JB.

The garboards

Having read JohnB's GLWB, it seemed to me that the planking was going to be a watershed stage in the build.  If I could figure out the spiling technique and master the cutting of the planks, and if they fitted, then I was well on my way to building this boat.

Well the good news is that the spiling techniques which John recommends using a compass, is much easier done than read.  So I was quite pleased with my efforts, although I decided to fair one station mark about 1/8" larger than the mold marks.  I'm hoping that this will be a good decision, but since it is the garboard, only the fish will be my critics...

This is the spiling pattern I made in action.

The spiling pattern is articulated in 3 places, thereby allowing it to fall onto the molds without too much torture.

This is the jig with JohnB recommends for the skill saw...I used an old acrylic display stand, hence the odd glue marks on the sheet - but it came for free and worked perfectly.

 Rather than nailing and screwing the planks temporarily to the keelson and molds, I screws blocks to the side of each mold station and used to clams to dry fit the garboards using clamps.  Seemed to work fine and allowed me to re-position the planks until I was satisfied it was aligned to its marks.

My test attempts at cutting half lap gains....

Half lap gains...

And again, using chisel and Quangsheng block rebate plane

Dory gains for the transom, using a spoke shave.  I've come to really enjoy using the spokeshave.  Initially all it would do was scrape and bounce off the wood, now having persevered with it, I can make really nice shavings, and it is a real pleasure to use.

I have opted to have curved planks at the transom rather than notching the transom, so JohnB recommends to make re-leaving cuts on the underside of the end of the plank.

 Garboards in place.

A short video on the garboards clamped to the molds and keelson before final attachment:

A view from the transom of the fitted garboards.  

Close examination will reveal I am using straight slotted screws.  This was to avoid a further 4 week delay in sourcing Frearson #10 1" screws.  Although JohnB warns of the horrors of using straight slotted heads, in fact they worked out fine and I didn't have any difficulties using an electric screwdriver to send them home.

Laminating the inner stem

This was my first attempt at creating saw dust from my lovely stock of Sapele.  I bought a new (secondhand) 17" bandsaw for this project so I was eager to put it through its paces, cutting laminates.  I was chuffed at how well the laminates came out, and before long I had 15 lengths prepared for my stem.

I glued up the laminates without incident, although I did not use any fillers in the epoxy mix, but so far the stem seems to have held together fine.

Flushed with early sucess, I then laminated up the outer stem on the inner stem.  It wasn't until I re-read the specifications  that I realised the import of the sequence of John's instructions - i.e. shape the inner stem after it is cured and THEN laminate the outer stem to the inner stem.  My outer stem is a little off as a consequence, but I am confident that it will bend back to mate with the outer stem, when the planking is complete, or failing this I will have to get out my lamination blocks and plans and re-do the outer stem.  Not the end of the world...

One small word to the wise....dont cut off the excess timber from the top of the inner stem - you will need this to attach the stem to the jig, only when the boat s off the jig should you cut it to its finished lenght.  I thought I knew better, I trimmed it back to about 2" longer than the finished length - had to re-glue the cut-off back on so that I could attach the stem to the jig.  Epoxy glues and wood flour make for a very strong joint!

Reading boat plans

All the information is there - yes really - you just need to explore and find it, (and learn a new language).  By all accounts John Brooks' plans are extremely details and come equipped with cut lists, materials lists and building specifications.  In conjunction with John's book Glued Lapstrake Wooden Boats, one can find answers to every question.  But you do need to look hard, especially for a first timer.  Having sent a few emails to my fellow workshop class mates, and receiving patient replies I began to realize that indeed all the information is on the plans...

Half breadths...yes that is an interesting concept, once you have made a stem exactly half as narrow as it should be (I didn't, but very nearly did!).  Most of the plans show measurements as half widths from the centreline.  The logic I presume is to ensure complete symmetry.  John is quite encouraging to his students about mistakes - as long as they are the same on both sides of the boat, no one may ever know...

Also I began to understand that when John writes his instructions they are exact and precise.  So when he says to build the inner stem and then shape to the Full Size Plan (FSP to you boat builders) and THEN laminate the outer stem over the inner stem, if you decide to simply laminate the outer stem over the inner stem before refining the shape of the inner stem, you end up with an outer stem which is out of shape...oh well, I am optimistic that I can get the outer stem to bend into shape, if not I can build a jig again for the outer stem in due course.

Plans can be unwieldy and so for the early stages of my build I had them rolled up in the corner of my workshop pulling one out when I needed it - and could reach it.  So the big learning for me was to cut a large 3'x4' hardboard and use paper clamps to hold the plans on the board for easy access.

Laminating Floor boards

JohnB 's instructions suggest laminating the floors on the molds before planking so that hey mirror the inside of the planking when installed later.

So using stiff battens screwed to the molds, the laminates are clamped to the battens and glued up in a plastic wrap to save on the epoxy mess....

Batens for laminating floors

It was an interesting stage for me as it was the first time I had several battens attached to the molds which gave me a picture into the shape of the hull, and onlookers could at last be assured it was a boat I was building!

Laminates cut from Douglas Fir in preparation for glue up

Cutting laminates became an easy task with helping hand from Ivor and my shop made feather board which ensure constant thickness in the laminates.  This is an enjoyable process which runs much faster than I had envisaged.

Here the floors are glued up, wrapped in polythene to reduce mess - it does have a down side as the next photo shows:-

Removing hardened epoxy from the boards was  a painfull, dirty messy job!

.  Were I to do this again, and I very well might have to, I would use more clamps.  I only used one clamp on each baten and two on the keelson, making 8 in total for each floor.  This left some voids between some of the laminates and you could see where more pressure was placed on the glue up where it was clamped.  Another issue showed up as by ensuring the floor was clamped tight to the bottom of the keelson, the floors then swept back at an angle to meet the batens.  Had I had my thinking cap on, I would have realised that most of the floors (at the centreboard) will be cut in half and in fact following the lines of the keelson was immaterial and in fact unhelpful.   Time will tell, whether I will have the re do these floors.

The finished floors

Building my jig

While awaiting delivery of my hardwoods and plywood, I took delivery of some spruce, larch and pine so I was able to begin building my jig - or strongback as I think it is also known by.

First my garage floor was very uneven and heavily sloped with a fall of around 5" over the 16' span.  Apparently, builders start by building the garage so that they can mix more concrete inside the garage for the build of the main house - that seems a reasonable explanation to me when I tried to comprehend the large lumps of concrete stuck to my garage floor.  So, I took the advice from GLWB and bought two large sleepers to lay on the floor, which I bolted to the floor and took out some of the fall in the fall.  Then I built out the legs for the side beams.  In the interest of having the three beams accurately aligned, I screwed them together and ran them over my planer together in an attempt to have them lined up.

I spent quite a while with my water level.  I'd read in John's GLWB where they had used food dye to colour the water to make it more visible, so I decided to add some ink, which had been idling in my office for some years.  Yes it makes for a nice visible colour in the tube, but hey does it create quite a mess when you forget to hold both ends level and black ink comes squirting at you, all and sundry!  So I abandoned the water level and took out a 6ft spirit level which seemed to work fine.  I later checked it with a lazer level and my measurements seemed good.  However, it's not a trivial job, certainly for me single-handed nad first timer, I spent quite a few days before I was satisfied that my jig was square and level.

While I had reasonable success in keeping the jig square and level, I did find the side beams warped and so I had to use a combination of clamps and windlasses, with 4' spacers in between to finish with parallel side beams.  Also, even though I had taken quite some time to carefully cut the angled timbers which support the centre beam on my mitre saw, I still had some jiggling to do to get a properly aligned centre beam.