I love my big 17' Jerry Briggs-inspired Grand Canyon dory from Andy Hutchinson's plans, but she's way too big for day runs.  Time to build a little boat.

10'-6" LOA

60" beam

36" floor width

~23" deep at the oarlocks

I made three paper mockups, and two smaller 1:12 tagboard mockups.  One final 1:6 cardboard mockup before committing to plywood:

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Cut the plywood. One piece ripped diagonally lengthwise, the bow panels out of the width of another sheet.  Side panels 11'-10"

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I was having a hard time getting straight scarfs with my saw jig, so I cleaned them up from here with a ROS and 60-grit. You want the ramps to all touch the previous sheet and the glue lines parallel. The top piece was really ugly and got re-cut entirely. This isn't fancy AA marine ply, just $30 AC ply from the box store. Not worried about knots; I'll be glassing the entire boat inside and out.

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I like woodgrain.  Used a latex exterior stain.  Oil based stains can interfere with the epoxy joint.

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Epoxy on the joint faces and clamped/screwed for the night.

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26: 16th and final lid lip

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This one was OK, but didn't quite get the glass pressed into the lip in the near corner.  Will drill a couple holes in it to fill with epoxy.

#15 from Tue night was the best yet.

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It won't even require sanding!

And great adhesion and fill of the glass that laps onto the inside face of the hatch.

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Day 27, Saturday, January 30. Crazy productive:

Trimmed the sheer, cut and laminated the gunnels, flipped the boat, cut and sanded the floor, trimmed the transom and stem, stained the transom, fixed the patterns, cut glass for the floor and sides, and ran out of gas!

Trimmed the sheer 1 inch lower in the middle, the backside isn’t yet cut in this photo

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Had beautiful weather yesterday starting with beautiful pink cotton candy clouds

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Laminated the gunnels, Jatoba faces with western red cedar core

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Clamped the gunnels to the bench to keep all the layers straight

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Getting ready to flip

Used one 1” ratchet strap. Solo.

Interesting but doable

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But wait...there's more!

Marking gauge to mark the floor joint

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Trace it with a pencil

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I marked the line but didn’t use it, I watch the blade from the bottom

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Trimmed close with the jigsaw and cleaned up with a block plane and then sander

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I round it to a ~3" radius.

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Trimmed the floor at the transom.  This got rounded to about a 3/4" radius.

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Plywood shadow

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Trimmed the sides at the stem:

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No...there's still more!
Like I said, crazy productive.

The biaxial glass for the floor is 51 inches wide, the floor is 36 inches wide. I cut the glass at 43 inches for about 3.5 inches wrapping over the sheer, and then have two 4-inch strips of tape I will also put on the sheer.
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I should have cut the side panel glass when I did the inside glass, rolled it up, and set it aside.
I marked out a diagonal with a chalk line

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Fiberglass cutting station.  Good thing I'm tall...it's over 5' off the floor! haha

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Got the floor glass in position and clamped the gunnels to the sheer line to take a curve, and called it an evening. 

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Sun, Jan 31, Day 28: glassed the floor and chines

Floor glass was slightly short so I added a bit of length when I glassed the chine tape

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Chine tape and fill coated the floor glass.

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this will have a lighter floor and sides, but heavier chine than the big boat.  1 x 20oz + 1 x 20oz tape, + 8oz plain weave.

I'll sand down the threads tonight and fair it with cabosil which is also nice and tough.

I was going to paint the chine black, but that will be too dark too high...going to make it gray paint to somewhat match the stain.

29: Glassed the sides and flow coated the bottom.

I'm really excited about how the stain looks under the glass.

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The scarf joint wasn't perfectly aligned so the panels overlapped too far and I have a hard spot.  I'll fair it out a little, but will probably just have to live with it.

With a flow coat, you can see how clear the bottom biax is. I really worked it to get the epoxy into the weave. And the Raka did a good job of wetting it out. Interestingly, I used the Fast hardener on the right and the 350 No Blush on the left, and wet-out and cure times were quite similar.

I didn't work the chine tape quite as much so it's cloudy.

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85 hours elapsed.
Everyone asked me on the big boat, and I didn't track my time.  I guessed 400 hours in it.  I started it mid-Dec 2018 and launched it Labor weekend 2019.  Worked steadily 7 of 9 months (with a big May-June slowdown to play on the rivers)
Looked through my FB album and I flipped Great Falls on May 1, 2019, had the sides and bottom glassed by May 15--about 5 calendar months to this point, working on it ~5 nights a week and some weekends
 
I started this project on Dec 27... a bit over a calendar month ago.  6 nights a week and most weekends.  Smaller boat means a less time sanding or applying epoxy, but I think I've gotten a lot more efficient, too.

30: flow coated the sides, cabosil mix on the chines and routed/sanded the gunnels. 

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Got a little sag in the flow coat on the sides, that will sand out before varnish.

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Epoxy thickened with silica fume.  It makes a translucent creamy paste about the consistency of Vaseline

"Silica fume is an ultrafine powder collected as a by-product of the silicon and ferrosilicon alloy production and consists of spherical particles with an average particle diameter of 150 nm". Very hard, very tiny dust.
It's makes a strong fillet, but is an absolute pain the rear to sand. For this reason, like my friend Chris Towles 
says, it also makes a great anti-abrasion coating for rocks and sand in the river.

So there's a layer of silica fume on the chines and floor. It gets quite clear when spread thin.

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1/8 roundover on the gunnels.
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The Jatoba is so much harder than the cedar, I sanded them with the freestanding drum sander so it cuts them both equally. With 100-grit belts, it is smooth enough for epoxy.

The jatoba is about 3/16" thick but I rounded it over at 1/8" to keep some of the hard stuff exposed on the very outside.  The cedar will ding comparatively easy.

31: 2nd fill coat on the sides, additional cabosil mix on the bottom and chines. No pics, use your imagination!

32: outwales and capped the edge of the ply on the sides.

Bold move: did both outwales.

Used all but one clamp.

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Capped the edge of the ply with a 1/4” wide scrap of ply veneer from trimming the sheer.

Partly for looks and mostly to keep water out of the edge of the plywood

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33-37.  Installing and glassing the deck hatch lips.  Lips #17-21

8 surfaces with one piece of glass.  Really happy how with this one came out.  Will take minimal touchup down in the grooves


The deck on the right was glassed before, but everything else in the foreground is a single piece of glass in one application with no fill coats.  Yay for plastic!

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9 separate surfaces on this side lip.

The gray area was scraped of excess epoxy while the epoxy was still green cured. 

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Adding 2 layers of glass on the top edge of the spare oar slot. It will see some abuse. 

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Lots going on here.

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I pre-cut and dowel the hatch lip and riser so they index in place....but don't glue them until a part of the glassing step. If I glued them first, I risk having the slot just a tiny bit too wide or tiny bit too narrow. Too wide means we end up with bubbles under the fiberglass, or worse--loose glass. Too tight and I can't fit the HDPE spacer down in the slot.

So we wet out the glass on a piece of plastic on the workbench, wet out the hatch lip, riser, deck, and all surfaces that will get glass.
Plop the lip and riser down onto their dowels to stay in place, then smoosh the glass in place. Separate pieces of HDPE drop into the drainage channel, then a piece of plastic sheeting that wraps over the lip, another piece of plastic locks it in place and smooshes the glass down onto the hatch step. Wrap the plastic down and around the lip and onto the bottom. Add some more HDPE strips to hold the visqueen in place, and clamps to hold the HDPE in place. The clamping pressure smooshes out any air bubbles and excess epoxy and gives us the nice finish we saw in the previous photos.

I do all this with messy gloves on and don't get any photos, so I'll take pics when I peel this apart in reverse.

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Full sequence of using HDPE strips to smoosh the glass around all the faces of the hatch lip and deck frame

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One layer of plastic protects my table saw (work surface) and the next layer of plastic is cut to shape and will actually remain with the glass and get smooshed in place.

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After the loose mahogany lip and the exposed deck surfaces are wet out with epoxy, drop the lip into place.  This is why I use dowels--even if there's some bend in the mahogany, the dowels keep it straight..and it's a lot easier than trying to keep it from sliding around while you're draping wet glass over it.

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Then I have a piece of HDPE cut the width of the lower gutter (3/8" and the height of the gutter to deck (1.125").  It smooshes the glass down into the lowest slot.

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that piece of HDPE tucks nicely into the slot and its top is flush with the deck.

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Next we tuck in the edge of a piece of sheet plastic that will help the glass wrap around the lip.

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And another piece of HDPE drops in.  It's 1/2" wide (3/8" lip plus 1/8" gap between the lips) and 5/8" high (lip height 3/8" plus deck height 1/4")  and sits flush with the first HDPE strip.  It clamps that piece of visqueen sheet plastic in place.

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Just a scrap of mahogany. It's 1/4" tall by 3/8" wide and presses down on the plastic on top of the lip.

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All those pieces are flush on top and flush with the deck.

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