Transition Joint - Utility

Outboard designs up to 14'

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Transition Joint - Utility

Postby largej » Fri Jan 30, 2015 9:18 am

What is the best way to locate the transition joint for side to bottom planking on a Utility Build?
I know it is aft of frame2 but not sure where. Looks like 10 -12 inches... Any advice on how to locate this would be great.
Also, can I just epoxy the seat risers in place? The plans don't really call out fastening.
Thanks in advance for all the good advice.

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Andy Garrett
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Re: Transition Joint - Utility

Postby Andy Garrett » Fri Jan 30, 2015 10:02 am

Just remember, the transition joint is just a place where get to use an easier method as we go aft with planking. If you think of the butt joint at the bow as a 180* relationship between planks and the lap joint near the transom as something close to a 90* relationship, then try to place the transition joint somewhere at the midpoint of that range.

Transition joints are not particularly critical when it comes to locations. Heck, you don't realy even need them if you don't mind doing the carefull work of beveling a butt joint all the way to the transom.

What you don't want is a wide area of plywood end-grain because you tried to do the transition joint too far forward.

I'm not sure what you mean by 'seat risers' but anything having to do with seating (weight-bearing) would be fasted with screws on any boat I built. Those joints take a beating when under way as passengers bounce up and down on them. In fact, any two pieces of wood on my Zip are screwed as well as glued with the exception of the frame gussets which are nailed and glued.
Andy Garrett

Perhaps the slowest Zip build in Glen-L history...

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Re: Transition Joint - Utility

Postby BarnacleMike » Mon Feb 02, 2015 2:53 am

Hi Jim,

Your Utility build is looking really good!

The transition joints for the side planking on my Utility are located approximately 6 inches forward of frame #2. As Andy mentioned, it's not an exact science on where to place this joint. Some builders have even placed them aft of the forward frame for aesthetic reasons. Specifically regarding the Utility, I wouldn't recommend placing the joint any further forward than 6-7" forward of frame #2, as the bend gets a bit stronger there & will be a little more difficult to work with. Something more like 4-5" forward of frame #2 might even be better.

There will be another "transition joint" to deal with later. It is a little different to deal with... and will be a more gradual transition. This will be along the stem, where the second side of the bottom planking will "transition" to lap over the first.

On the seat risers: If you're talking about the full-length seat risers that pass through those cutouts on frame #1... From the Utility builds I've seen so far, almost none of them have had the full-length risers. Most people seem to only attach them directly under the seats. That is probably what I'm going to do with mine. In all probability, I'm only going to epoxy them to the side planking.

Here's a link to the part of my blog that deals with the transition joint, if this might be of any help:

Built Utility "Perseverance" — completed Aug 2016
Currently building a Zip
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