Technique for Casting
the
Mast-Step Fasteners
into the Deck with Epoxy

I reviewed my Gudgeon Bros Boat Repair manual and their on-line user manual, but still had some unanswered questions... so I called Tech Support at West Systems. Here's what they suggested... use 5/16" machine screw and SS threaded inserts.

1.Using the original holes in the deck, position the hinged step and trace around it so I can position it accurately later.

2 Enlarge the diameter of the four holes to accept the threaded insert, tothe depth of the threaded inserts when they are flush or a hair proud of the top surface.

3. Coat the step and machine screw with PVA mold release or Pam, so they don't adhere to the epoxy. Put the machine screws thru the holes in the hinged plate, put a sheet of mylar or garbage bag plastic on the bottom surface of the plate, and put the threaded inserts onto the screws so they touch the underside surface of the plate. Don't coat the outside of the
threaded inserts with mold release or Pan -- the threaded inserts need to bond to the epoxy.

4. Prime the inside of the hole with plain epoxy. Fill/smear the hole with thickened epoxy; don't overfill the hole; you don't want a lot of epoxy getting pushed out when the insert and machine screw is lowered into the hole.

5. Place the assembled plate, machine screws and threaded inserts down, so the threaded inserts are in the epoxy. Tape it in place with duct tape. Let it cure.

6. Then back out the machine screws, and remove the plate.

7. Reassemble with bedding compound.

Notes:

a.) Putting the threaded inserts at the top of the hole prevents it from being pulled out when the machine screw is tightened.

b.) They didn't recommend drilling and tapping into plain epoxy because it's quite brittle and easily stripped. Without the threaded inserts, the epoxy "threads" would strip easily as the fasteners were tightened. This type of installation is much stronger.