1984 Montgomery 15 Sailboat Mast Gate Plates

The Montgomery 15 sailboat mast has a pre-feeder gate for inserting the mainsail slugs into the mast slot. When the mainsail is dropped, without a mast slot stopper or a mast gate, the slugs will fall out of the pre-feeder slot. If you use a mast slot stopper, above the pre-feeder gate, then the mainsail is several feet above the boom, which presents substantial area to a strong wind. The stopper also makes it difficult to flake the mainsail onto the boom.

These mast gate plates are designed to fit over the mast pre-feeder slot and allow the mainsail slugs to travel down to the bottom of the mast slot, and onto the boom.  The mast gate plates hook over the existing mast slots and are tensioned to the far side of the mast using bungee or elastic cord.

There is a slight difference between the port and starboard mast gate plates included with this project as I found, with my mast, that the pre-feeder slots are not symmetrical. YMMV, depending upon your mast manufacturing techniques. Try printing the starboard plate first to see if it fits both sides. If it only fits one, they print the port plate to see if it fits the other side.

I printed these plates on an OPXL2H using Polymaker PETG using input shaper and .32 structural. I used an enlarged brim as the plate is tall and narrow. I also used gyroid 20% infill and 2 perimeters.

I included a .3mf files with the seam painted on the trailing edge of the plates to minimize zits.