Utility build

[BarnacleMike]

A couple of months ago, I decided to suspend work on my Squirt and build the Utility instead. Progress has been very good, although I don't believe I'll have it ready in time for G6, unfortunately. I learned my lesson from taking a few too many shortcuts on the Squirt (namely in my choice of lumber), and I'm building this one from mahogany lumber and DF marine plywood.

This time around, when assembling the frames, I used a technique I saw online... I drew out the full-size frame on 1/4" DF and actually epoxied the cut mahogany pieces to it. I'm hoping this technique will help ensure that the frames are shaped correctly. (On the other side, I added the regular 1/4" DF gussets).

All the frames are now ready for encapsulation & my goal is to have the keel laid by the end of the month.

[Iggy]

That should make a nice strong frame, but will add a bit of weight & cost to the build. I used a series of nails to pin the frames into shape to plywood board with wax paper in between to prevent bonding. My frame shapes turned out pretty much spot-on.

[jprice]

Very nice. I like that method.
Considering the amount of frames on that model (I'm assuming 2?), the amount of additional weight and cost should be quite minimal.

[BarnacleMike]

Jeff, you're right. The Utility only has 2 frames, so there won't be much added weight. As far as material usage, it "cost" about 2/3 of a sheet of DF ply. I used the waste from the cutout areas to make the remaining 6 gussets.

I was originally planning to make a U-shaped aft seating arrangement, but if possible I'd like to simply eliminate the side aft seats. I'd prefer to simply have two amidships bench seats, but I'm not sure if those side seats are important structurally (as in transom support).

[BarnacleMike]

A question: What is the difference between "Keel" and "Keelson?" Do I understand correctly that a "Keelson" is inside the bottom planking, and a "Keel" is outside the bottom planking?


The keel (keelson?) of the Utility is designed to be made of 1" solid lumber, laminated on top with a layer of 1/4" plywood. So, naturally, the frame notches on the centerline are drawn to 1-1/4" depth & that's how I cut them.

When rough-fitting my keel into the frame notches, I realized that the solid mahogany part was only 3/4" thick. So, the keel overall was too thin, and fit too deeply into the frame notches. I decided to laminate a second layer of 1/4" plywood on top, and since I didn't have a full 8' length on hand, I scarfed two shorter pieces together. It was my first attempt at a scarf joint, and was done with a small sander at that, so it's not very precise. However, it's functional & the resulting keel seems to be quite strong.

The other issue with fitting the keel is the fact that I did not make angular cuts into the transom frame notches. So, when the transom was put onto the construction form at a 12 degree angle, the mating surfaces for the keel also turned 12 degrees. Add to that the fact that the keel sits at a 1.5 degree angle to the longitudinal reference line, and I realized the end surfaces of the keel would need to be beveled 13.5 degrees to fit properly into the transom frame notch. The end cut was easy enough to make with a circular mitre saw. I used a sander to bevel the plywood edge. Here are a few photos...

[BarnacleMike]

... here are the photos of the scarf joint.

[BarnacleMike]

I've seen the word "Keelson" used differently in various places & sometimes interchangeably with "Keel." Here's what I found, for what it's worth:

Apple Dictionary:

keelson |ˈkēlsən| (also kelson)
noun
a centerline structure running the length of a ship and fastening the transverse members of the floor to the keel below.

ORIGIN Middle English kelswayn, related to Low German kielswīn, from kiel ‘keel of a ship’ + swīn ‘swine’ (used as the name of a timber).

Wikipedia:

The kelson or keelson is the member which, particularly in a wooden vessel, lies parallel with its keel but above the transverse members such as timbers, frames or in a larger vessel, floors. It is fastened to the keel partly to impart additional longitudinal stiffness to it but principally to bind the longitudinal members (keel and hog) to the transverse members (frames and floors).

[BarnacleMike]

My goal for August was to get the keel and stem mounted. I'm almost there... The keel is "glued & screwed" into place. I've got the stem aligned and bolted on with bronze carriage bolts. I just need to take it apart, glue it, and put it back together. Slow progress, but it's getting there.

[BarnacleMike]

A little more progress... The Stem/Breasthook assembly is now glued & bolted into place, with a couple of glue blocks also. Last night I got the transom knee assembly glued & screwed. Here are a couple of photos from my phone...

[darthplywood]

looking good! keep the progress and the pictures coming!

[Roberta]

Look's Great, Mike!!! Keep posting and keep up the good work.

Roberta

[mrintense]

Very cool. I haven't gotten to the gluing stage just yet but it's exciting to see other's progress at different rates. Great work so far. Looking forward to more pictures.

[BarnacleMike]

Not much new to report... I've cut the floor battens & am fitting them. I found a hole in one board & am trying to decide whether or not to use it. I'm thinking that if I use it with the hole at the aft end & fill it with epoxy that it should be fine.

I'm also trying to plan out my floor before I permanently glue & screw the battens in. That way I can add the related supports to the frames while the whole thing is level & on the construction form. My goal for September was to get all the battens installed, so I guess I'm not too far off from that.

[jprice]

I had the same thing in one of my lift strakes. I just did like you mentioned and placed it so that it was in the flat/straight section in the aft of the boat. Then filled with epoxy. It's rock solid as far as I can tell. Should be a non-issue.

[rbrandenstein]

Looking good, Mike.

Since a glued joint seems stronger than the wood, I think filling it with thickened epoxy would be just fine.