Constructing Mast Beam Template

One issue with the Sea Sprite 23, seen more than once, is deflection of the deck where the mast is stepped. I have seen balsa-cored decks re-cored due to water saturation, ultimately causing the deck to flex where the mast is stepped. I have seen repairs made to non-cored decks as well - most likely due to general wear and tear over the life of the vessel, and in my opinion what appears to be a relatively weak design for the mast beam. Froonie does not have cored decks. She does have a mast plate glassed into the overhead, and from all of my inspections thus far appears to be dry. Froonie did, however, develop some issues with the mast beam, eventually causing the deck to flex. The PO installed a couple of 2x3 beams onto the forward mast beam - essentially sandwiching the forward mast beam between the 2x3s with four bolts.

With the reinforcing 2x3s removed, you can clearly see the stress crack that resulted from continual flex of the fore deck. I will be drilling into the mast plate itself to examine whether this plate needs replacing; I will be specifically looking for deterioration due to water intrusion. If water is or was present…yep, I will be cutting this support out and glassing in a new mast step plate. Here is a picture with the reinforcing 2x3s removed and a temporary vertical support in place.

I had made a decision

to strengthen the fore deck regardless of how the examination of the mast step plate went. So to that end, I proceeded to lay out a template of the mast beam to later be cut out of red oak.

I have found yet another use for duct tape…remarkeable! I had originally thought about hot gluing strips of thin wood (veneer) or using cardboard to create a template of the original mast beam, following the overhead camber. But, as it turns out, duct tape seemed a much easier approach.

I ran a length of tape across the original mast beam, careful to keep it running along the bottom edge, and roughly every two inches I taped a thin dowell in place. The dowell sat vertically on the tape, and spanned the bottom edge of the mast beam to the overhead, or underside of the deck.

After the dowells were in place, I ran another layer of tape over them to secure the template. I then carefully pulled the bottom layer of duct tape off the mast beam, and placed a length of tape across the back, eliminating any sticky surface area. Done. I would later lay out the template on prepared red oak 1x4" boards for cut out.