An anchor roller, or bow anchor roller, serves an important function on a marine craft anchoring system. Anchor rollers ---typically consisting of a pulley guide wheel, extension mast, bearing support system and block mount --- keeps the anchor chain and rode positioned in a steady guide wheel, which extends over the bow lip of the boat. It keeps a safety margin between the chain and rode, preventing scuffing contact with the boat hull. It also keeps the bow in the wind, reducing snags and line shifting from twisting forces. A DIY repair person can mount an anchor roller on his craft, using some basic tools.
Stabilise the boat by transporting it on a trailer to a convenient work location. Place the anchor roller on the deck of the bow, and position the mounting surface as far back (aft) as you can, while still allowing the mast extension to overhang the bow.
Center the mounting bracket on the bow, equidistant from starboard and port sides of the bow. Use a felt pen to outline its position on the deck and mark the drill holes on the deck. Draw the same outline of the mounting bracket on a piece of half-inch-scrap teak, and on a half-inch piece of scrap marine plywood.
Cut the teak and plywood panels with a handsaw to match the profile of the mounting bracket. If triangular in shape, over-cut the long pointed end of each wood piece and saw the sharp points off. Place the teak panel under the mounting bracket and stick a drill bit through the mounting holes and press down to mark the starting holes. Do the same with the plywood piece. Use a drill and half-inch bit to drill all the holes through the teak and plywood panels.
Drill the three mounting holes into the bow deck with a half-inch drill bit. If the deck is made of sandwiched core, tape the bottom (underside) of the holes to close them off. Pour enough epoxy resin into the top side of the holes to fill up each cavity. Let the epoxy "tacky" up, so when you remove the tape the resin will not flow and drain down.
Apply a thick coat of bedding caulk on both sides of the teak panel and align it over the holes in the bow deck. Set the anchor roller over the teak panel and stick three stainless steel bolts into the holes, with the bolt threads facing down.
Apply bedding caulk to one side of the plywood panel and have an assistant place it under the bow deck, sticky side up and in alignment with the mounting bolts. Hold the top of the mounting bolt heads down, while the assistant shoves the plywood panel up against the underside of the bow deck, with the bolts extruding through the wood. Have the assistant place one spacer then one nut on each bolt and tighten them by hand.
Use an end wrench to hold the bolt heads from the topside, while the assistant tightens each nut (below) with the same size end wrench. Keep the mounting bracket centred while the assistant tightens the nuts. You will have some play to do this, since the holes are a half inch in diameter and the bolts measure three-eighths inches. Once the bow roller bracket has been firmly tightened, wipe away all excess bedding caulk from the top deck and bottom. Let the resin and bedding dry for at least 24 hours, or according to directions.
You may wish to use lock washers between the spacers and nuts, if you wish, but the spacers will provide a better distribution of stress load when used by themselves. If you have a sailing vessel with a bow sprint, you will have to drill side mount holes through the bow sprint and mount the bow roller on its side. Make sure the bolts go through all the way through the bow sprint.
Tips and warnings
- You may wish to use lock washers between the spacers and nuts, if you wish, but the spacers will provide a better distribution of stress load when used by themselves.
- If you have a sailing vessel with a bow sprint, you will have to drill side mount holes through the bow sprint and mount the bow roller on its side. Make sure the bolts go through all the way through the bow sprint.