Points East pram: Interior design completed

May 2022

By Clint Chase

First, I’d like to thank everyone who has been following this article series and reached out to say “hello.” I have made some sporadic progress on the pram dinghy project. I’ve decided to focus on the 8-footer and take it to completion. It won’t be much to extrapolate up and down a foot with the learnings from finishing the 8-foot version, the largest pram we can get from a sheet of plywood, and what I anticipate will be the most popular size. It has been enjoyable to take some time away from kit cutting and the vagaries of running a business to do some design work on the Pram.

The 8-foot Points East Pram hull form remains unchanged. The numbers are as I reported in last month’s issue (“Points East Pram: Displacement calculations” March/April 2022), but the interior is designed.

In my experience, with using prams as tenders, when you row solo and take on a passenger, you will need to move to the forward seat and row from a set of oarlocks about 12” aft of this seat. I decided not to go for a fore-aft seat but instead have a middle seat that can move. So, no need to slide forward. Where that can be handy to do, however, is when you have a smaller person aboard or gear in the stern, and you need to move forward a little bit.

So, I have used a “seat riser” feature that has become somewhat standard in my rowing boats. This horizontal riser forms a “shelf” that allows the seat to move forward to a new location (further forward). The seat lifts and is set back down, then held in place with simple dowels on the underside. This fore-aft moveable seat will allow you to trim the boat properly. Another benefit is that when you need to fill the boat with stuff, the seat can lift out completely to open up the inside for gear.

The rest of the boat is pretty simple on the inside: two enclosed plywood tanks, i.e., seats, in the bow and stern, can be kept airtight with a good fitting deck plate, or it can be filled with foam. Oars for the boat – 7-foot, 6-inches are perfect. They will stow on the diagonal and can be lashed to the seats. The hull planks are bent around the middle frame, fore and aft bulkheads, and screwed to the transoms, which are made of two layers of 9mm plywood. Most of the plywood for the boat is 6mm marine plywood. Okoume or Meranti can be used. A lighter boat will result from using Okoume, a wood that is more like cedar or pine. Believe it or not, my calculation tells me this boat will weigh 56 lbs. and I am known to be pretty close. If the boat is built carefully, with “lightweight” in mind, then a sub-60 lb. weight should be easy. To achieve this, we will use minimal fiberglass and epoxy, light but strong timbers, stick with Okoume plywood, and use urethane paints which are lighter than traditional oil enamels.

Though heavier, we may use Meranti plywood for the bottom panel because of its properties – denser and stronger – and Okoume for the remaining parts: transoms, side planks, transverse structure and tank tops. We’ll use lighter hardwoods for the rub rails, while the bottom runners will be a tough hardwood like Oak (but UHMW plastic can be used for those who want to really armor their bottom with something that can be replaced).

I like the way hardwood runners stiffen the bottom. So, that will be my preference as the designer. The skeg on this boat should keep her tracking straight, especially the way it tabs into slots pre-cut on the centerline. Speaking of tabs (you can see in the images), the tabs that stick through the hull! Don’t worry. These will be trimmed off flush after the hull is glued together.

The prototype will be built at Chase Small Craft in the coming weeks and hopefully in time to report about the experience of the build for the June 2022 issue of Points East. We’ve done enough prototype builds to be confident that it will go well, but it is always interesting to see where the sticky points are and the easy spots are in the build process.

It will be important that this boat “practically builds itself,” so I will be looking for difficult areas and places where things can be done more efficiently. Moreover, I look forward to seeing the ways this little project can be used as a teaching tool to introduce people to the joys of building (and using!) their boat, as well as the ways this boat can effectively teach in a 3-day workshop, the skills someone would need to build their own boat from a kit.

See all the articles in this series on our Points East Pram page.

Clint is continuing to take suggestions from our readers on this project. Feel free to email him suggestions or comments at boatkits@gmail.com or share your general thoughts on this endeavor by emailing editor@pointseast.com.