Bumper Construction

Materials to Order (Off-Season)

Minimum material needed for 1 season

  • Iron On Numbers
  • Populate our team numbers
  • Order 8
  • Bumper Fabric
  • Populate team numbers
  • Order 1
    • Enough for 1 set (left and right) of blue and 1 set (left and right) of red

Assembly Materials

  • Painter's tape
  • Plywood (bumper wood)
  • Dory mounts (bumper mounting plates)
  • Rivnuts
  • Bumper fabric
  • Bumper foam (white 2-inch foam and black foam)
  • Sharpie
  • 1/4" drill bit
  • 5/16" drill bit
  • Countersunk drill bit
  • 1/8" drill bit (pilot holes)
  • 3 drills
  • Tape measure
  • Calipers
  • Mallet
  • 1/4-20 nuts
  • Clamps
  • T20 star bit
  • Bumper items box
  • Double-sided painter's tape

Assembly Process

1. Prepare the Angle Iron

  • Cut pre-drilled angle iron / L-channel to 4.5 inches long.

2. Prepare the Wood

  • Measure wood to ensure accuracy to CAD dimensions.
  • Mark wood with measurements using a Sharpie.
  • Build bumpers segment by segment.

3. Drill Holes for Rivnuts

  • Drill out holes using a 5/16" bit (through hole).

Wood with drilled holes for rivnuts

  • Mallet rivnuts into the drilled holes.

Rivnuts installed in wood

4. Attach Angle Iron to Wood

  • Attach angle iron to the wood.
  • Drill through using a 1/4" bit (through hole).
  • Countersink the wood side so the fastener sits flush.

Angle iron attached to wood with countersunk holes

Angle iron corner detail

5. Add White Foam

  • Put white 2-inch foam onto the bumper wood.

White foam placed on bumper wood

  • Measure the foam from edge to edge of the wood.
  • Cut the foam to measurement.
  • Tape the foam down to the wood with painter's tape.
  • Attach double-sided painter's tape to the surface of the white foam.

6. Add Corner Foam Pieces

  • Attach 45-degree angle foam pieces to the corners.

45-degree corner foam pieces

7. Add Black Foam

  • Wrap black foam all the way around on top of the white foam.

Black foam wrapped around white foam

8. Attach Fabric

  • Put the bumper fabric on over the foam.

Color Order

Repeat for each color (🔵 blue and 🔴 red). Complete all steps for one color before starting the other.

  1. Cut the fabric in half lengthwise (~100").
  2. Test fit the fabric on one of the wood bumpers.
  3. Iron on one set of numbers in the center of the fabric.
  4. Stretch the fabric tightly over the foam and wood, fold it around to the back of the wood, and staple or tack it down every few inches to keep it taut.
  5. Trim any excess fabric at the corners for a clean finish.

9. Attach Dory Plates

  • Clamp dory plate onto the wood.
  • Drill a pilot hole using a 1/8" drill bit.
  • Countersink the dory plate.
  • Screw dory plates into wood using wood screws.
  • Ensure the wood screw sits flush — no extra thickness.

Notes

Common Mistake

Ensure wood is lined up properly before drilling. Misaligned wood is the most common assembly error.

Filling Corner Gaps

If there are gaps between the corner piece and the black foam, slide in chunks of scrap white foam to fill the space.

Cutting New Foam

When cutting new foam on the vertical band saw:

  1. Measure the height of the bumpers using calipers.
  2. Three people are required:
  3. One person slides the bumper foam along the vertical band saw.
  4. One person holds the foam to keep it from curving back into the blade or machine.
  5. One person pushes the foam from behind.