A finished stem

I completed the outer stem recently.  I did this by laminating nine 1/4″ ash planks and then shaping them to the contour that I wanted.  I spaced the bolt holes about 8″ apart and used a forstner bit to countersink and make holes for the bolt heads and plugs. The bolts will be 5/16″ diameter and the countersinks need to be large enough to accomodate the washer (about 3/4″), but it’s best to go a little bit oversized.  Finally, the bolts run through the inner stem as well and are 6″ long.

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Finished stem

I cut out the stem contour with an oscillating saw, electric planer and angle grinder.  I used 50 grit on the angle grinder and it left some deep scuff marks as one might expect.  When working with ash, it can be significant work getting these scuffs smoothed out.  You just have to  keep at it with the finer grits on a belt or orbital sander.  I went up to 320 on the orbital sander.

The next step is install and secure the bolts on the interior side with 5200 marine sealant.  I will also need to install a long eyebolt for a painter (rope for pulling the boat).

Next step is closing up the port side of the hull.  Forward progress.

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Finished planking out the Starboard side; Outer Stem take two; Second wood order

The starboard side planking is done. Since the remaining gaps were irregular, I used dividers to measure the spaces at 6″ intervals and then transferred them to 2 planks that were pre-glued together. I then connected those points with a batten and planed it out…a few iterations with both electric and hand planes.  It was similar to finding the shape of the whiskey plank for canoes (i.e., the last plank to close up the hull).  I still have a lot left before I can call that side done (plane it fair, sand, add the guard and spray rails, plug up the screw holes and fiberglass…..) but I can say that the starboard side is closed up!

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Pre glued planks.  I used dividers to find the gap sizes, tranferred to my pre-glued planks, connected the dots, and then planed out the shape.

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Planing in progress

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Planks in place.  I had to do some dialing in but it worked out pretty well.  Since I couldn’t use clamps, I nailed the planks into the ribs.  I’ll take out the nails once the epoxy dries and replace with screws.

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Top view.

I need to leave the port side open for now in order to finish the outer stem.

The outer stem had to be redone.  I tried to force down too many ash laminations last time and unfortunately ended up with gaps that couldn’t be faired out.  Live and learn.  Since I’m capping the outer stem over the inner stem, that connection needs to be tight and waterproof.  There’s just no wiggle room on that.  So, I got some threaded rod, fender washers and bolts to pull down 1/8″ ash laminations as I add them on.  The threaded rod is 1/8″ to 3/16″ undersized, and the fender washers have tape on the bottoms so things won’t get stuck after boards are epoxied.  I saw this method on youtube, video is linked here (tipsfromashipwright).

I’ll dry fit and add them on one or two at a time to ensure I get the conformity I need, then will epoxy them together, and repeat the process until done.  The first lamination will be attached to the inner stem with 5200 marine sealant.  There’s a good reason that stuff is called “the devils glue”.  It really works.

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First ash lamination dry fitted.  The holes will later be used for carriage bolts. I used threaded rod and fender washers to ensure a tight fit to the inner stem.

 

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Dry fit successful, ready to apply 5200 between the inner stem and first lamination.

I also got a second order of wood a month or so ago.  I get it from a local cabinetmaker, Bruce Long Woodworks, and it’s really good stuff.  Tight vertical grain dfir and very nice looking ash.

I used some of the dfir planking for decorative woodworking this year, plus I needed spray rails, sheer clamps, etc,…so…I got more wood.  Below is what I ordered.  A word of advice, 20′ lengths of ash are pretty difficult to find, expect to get shorter lengths and scarf them together.

Douglas fir:
– Planking – 30 pieces at 3/4 x 1 3/8 x 16 feet
– sheer clamp 2 pieces at 3/4 x 2 3/4 x 14′
– shelf 2 pieces at 1 1/2 x 1 3/4 x 14′

Ash:
– Spray rails – (2) at 1 1/4 x 1 5/8 x 20′
– guard (4) at 1 x 2 3/4 x 20′
– Outer stem – 12 pieces at 1/4 x 5″ x 7′
– Transom planks – 5 pieces at 1/4 x 6″ x 7′

Next step is to finally finish the outer stem.  I also need to get the boat on bigger casters so I can wheel her in and out of the garage.  The holidays will slow me down some but I’ll keep plugging away.

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Forward progress!

Keel shoe attached

I scarfed and attached the keel shoe this past weekend.   I used an electric planer to make the scarf this time and it came out pretty good.  Plus it was much faster than my normal method where I slowly dial it in and only take off a little bit of wood at a time.  Once the scarf epoxy dried, I knocked off the sharp corners of the 17′ length with a trim router and set up the fastener holes about 8″ apart.

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Keel shoe dry fit.  Since the stem/keel/keel shoe intersection was most important, I started fastening there (i.e., at the bow) and worked my way aft.

The keel shoe is attached to the keel with fasteners only, i.e., no epoxy.  The shoe takes abuse from trailering, hitting limbs in the water or running aground, so it needs to be removable.

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View from the transom.  I knocked the edges off of the shoe with a trim router.

The fit up went well.  The stem and keel angles both look pretty good and everything seems nice and tight.  I’ll add some more laminates to the stem soon so that it’s flush or a little proud above the keel shoe, but so far I’m happy with the results.

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Keel, keel shoe and stem fit up.  I need to add a few more laminate layers to the stem but so far so good.

My grandfathers tools continue to do the brunt of this work.  Probably over 70 years old and they’re my workhorses.  Forward progress.

Scarfing and placing the keel

I scarfed two 9′ lengths of keel timber together earlier this week.  It’s an 8:1 ratio with epoxy and screws to make it nice and tight.  I then bolted and epoxied my new 17′ 8″ long keel to the boat (the scarf runs 4″ along a 1/2″ slope).

My sequence after scarfing was thus –

  1. Dry fit the entire length of the new keel to the keelson to ensure the angles are right
  2. Clamp down while on the boat and then pre-drill the carriage bolt holes and countersinks.  The countersinks ensure there’s enough room for washers.
  3. Place the 3″ carriage bolts in their holes, keelson side, about 1/4″ shy of flush
  4. Pour the epoxy in the keelson and brush.  Be liberal.  I used US Composites, 3:1 ratio medium mix. It comes out pretty thin but I prefer it that way (you can thicken it with wood flour or silica).
  5. Brush epoxy on the keel.  This ensures both mating surfaces are wetted out and gives a better chance of “stiction”.
  6. Place the keel.  Knock in and tighten the carriage bolts starting at station 12 (in my case) and working your way down  to station 1 and finally the transom knee.
  7. Check your level at different intervals and dail in with gear clamps as needed.
  8. Make one last pass at the carriage bolts, taking up any slack as needed.

Some lessons learned – it would’ve been easier to affix the keel at the very beginning of the build.  I could’ve used the same carriage bolts as were used to secure the floor timbers to the keelson, the angle for the garboard strakes would’ve been easier to manipulate and not needed dialing in with a sander, plane, etc, and finally it would’ve made bolting the outer stem much less space constrained in the forward end of the boat.

Next step is to scarf and place the keel shoe, which protects the keel from abrasion, damage, etc.  Much better to damage and replace the 1″ keel shoe than the actual keel with all those bolts, attachments, etc.  I also plan to get the outer stem attached in the next couple of weeks.  Forward progress!

Done with floor timbers

I finished the floor timbers over the past  couple of weeks.  They weren’t the hardest part of the build but there are a lot of little things that have to be done, so they took a lot of time.  I was generous with thru bolts, as they give protection against lateral torsion, i.e., the sides of the boat flexing too much in reaction to waves, slapping down on the water, boat speed, etc. If I had it do over again I would install the floor timbers and ribs at the same time, before any planking at all.  That way everything stays in the same plane with a lot less work.

I used a template (jig) to keep my bolt holes consistent.  There was limited mobility between the stations, so I had to get a right angle drill attachment – another reason to shape and install the timbers and ribs at the same time.

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My template for drilling consistent holes for floor timber bolts.  I spaced the bolts about 6″ apart and alternated holes as I went up the boat.

The right angle drill attachment helped a lot.  I wanted the holes centered on the back of the rib, so I started the drill hole there.  If I’d started from the floor timber side, the drill bit could’ve drifted off center and created a weak spot for the bolt to break through the rib.

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I needed a right angle drill attachment to get into tight spaces.  It worked pretty well.

 

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All holes drilled and ready for through bolts.

I was generous with the marine sealant (5200) for the floor timbers.  I figure that the outer hull will be fiberglassed and trailered, so I really need to protect against residual water after the boat is pulled out.  The 5200 protects against water intrusion and also allows some flexibility (unlike epoxy).  I’ll most likely fillet 5200 to all of the inner hull interfaces once I flip the boat over.

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Thru bolts with 5200 marine sealant applied

Finally, I had to sister in a section for starboard rib #9.  The rib split as I put in a thru bolt, so I cut out that section, made two smaller new to buttress it, epoxied them together and bolted them up. I feel pretty good about it.

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The keel and keel shoe are next.  Forward progress!

More floor timbers; prepping the outer stem and keel; getting ideas from the Reedville boat show

I cut off the protuding plank ends near the stem and planed them all to the same length.  I also made their widths flush with the inner stem.  This was because I decided to change things up and use ash for the outer stem and other exterior hull accents, like the spray rails and guards; plus I’m overlaying 1/4″ ash planks on the transom.  I just think it will look better having white ash for the trim and light brown d-fir for the primary color.  So the dfir outer stem that I’d laminated and had ready to go will now be used for something else.

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Planking trimmed flush to the inner stem. Ready for the outer stem, which will basically be fitted right on top and then planed similar to the pic below.

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My concept for the outer stem.  This is from the Reedville boat show this past weekend.  This particular outer stem was capped over the inner stem…it matches the angles at which planks land and looks good too.

As I was roughing out timber #10 I found a knot in a prime spot for torsion, so I decided to take it out.  The structural members and hull will constantly be twisting and flexing while on the water,  so given that this knot could basically crumble if left in – which could cause timber 10 to split and put undue stress on the ribs and hull – I decided to take it out and put in an oak dowel piece.

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Knot in the mating surface between timber #10 and the keelson

 

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Drill the knot out with a forstner bit

 

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Put in an oak dowel and some glue until bottomed out.

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Cut off at the surface. Proceed with finishing sanding and fitting up. It’s best to align the grain patterns though.

One of the tricks I’ve learned for drilling straight holes through an 8″ floor timber piece is to lock in alignment of the drill bit with the plane you want it to drill through.  My 5/16″ bit is about 12″ long, so it can drift.  When that happens and my hole is way off, I’ve wasted all that time finding the timber shape, roughing it out, etc.  So I developed the little jig below to keep things lined up.  Since this timber is bolted to the keelson, a true-center hole also means the keelson hole will be drilled accurately too.

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As long as the drill bit stays on the centerline, in the groove right under the hole, and flat against the wood guide, the bit will come out on center.

Another interesting thing I got from Reedville was the use of a long threaded rod for deck eyelets and lifting rings.  These eyelets and rings are used to haul the boat out of the water and onto the trailer, or to turn the boat over.  That’s a lot of stress that shouldn’t be concentrated.  In other words, you really should spread it out as much as possible.  This rod connects to the floor timber, which of course connects to the ribs, planking and keelson.  I also like the idea of the knee behind the inner stem, which I plan to use.

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A wooden knee supporting the inner stem…plus a threaded rod from the a lifting ring on the deck, going all the way down to the timber. Both the knee and rod give significant strength to the boat when being pulled out of the water onto the trailer.

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Finding the shape of Timber #11. Keeping it simple with a glue gun and wood tabs. I’ll then transfer the shape to a 2x8x8 resin’ed pine board (2″ x 8″ x 8′) and cut out.

I’m almost out of room for working on the floor timbers, at least until I flip the boat.  I just can’t fit in the forward end of the boat with the moulds still there….but I also need to get all of the timber bolts through the keelson, mated up and epoxied before I can put on the keel.  So I’ll have to figure that out.

I can see the exterior hull getting done and the boat flipped sometime in the next few months.  Forward progress!

Floor Timbers, part 2

I’ve made some progress on the floor timbers, which run athwartships (across the width of the boat) and span the bilge area, or the lowest points of the boat.  The provide a lot of strength and reinforcement here, the area that takes the brunt of the shear forces and twisting motions of the boat.  The books all say that floor timbers “combine two halves of the boat into a whole boat”, which makes sense.  They are thick, resined, sturdy pieces of board that reinforce the ribs, keelson and planking, are epoxied to all three, and are attached through the keelson with a carriage bolt.

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Tightening the carriage bolt through the keelson

Finding the shape of the floor timber was similar to what I showed with the sole beams.  A cardboard template, craft glue gun, and thin pieces of board gave me the basic shape. From there I roughed them in with a circular saw and electric planer, and finally dialed them in with an angle grinder with sanding disc.

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Finding the floor timber shape with a cardboard template, craft glue gun and thin pieces of scrap board

A useful tip is to use your craft glue and put clamping pads on the floor timber boards.  Having them on the floor timber before you start clamping saves you the aggravation of trying to hold multiple things in place and work a clamp when you only have two hands.  The craft glue doesn’t leave any marks and just pops right  off with a knife.

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Craft glued clamping pads. 

I dry fit the floor timber  and mark off where the epoxy will go, then pull it out and apply the epoxy while it’s out in the open and there’s plenty of room.

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Epoxy applied, ready to install

Finally I put the board in place, make sure there’s good epoxy squeeze out, make my fillets and make sure the carriage bolt is properly seated.  I then put some of the leftover epoxy in the bolt hole and seal it with a section of oak dowel.

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Fitted and epoxied up, with an oak dowel in the bolt hole.  Note the clamping pads I’d mentioned up above.  Tip – make small grooves in the dowel before putting it in place, this gives the epoxy and glue a place to go and hold better.

I tried this exercise before back in December 2015 but decided to go with this method instead.  It accomplishes the same thing in much less time.

Forward Progress!