Step 1 Cut 1 sheet of marine ply to 850mm wide. Mark out 2 L-shaped sides (A) in opposite corners. They steps step1 step 2 step 3 step 4 step 7 step 12 step 11 step 10 Protect your precious surf gear from dings when out of the water step 8 step 9 are 1925mm high with uprights 120mm deep. Feet taper from 170mm at front to 150mm at back. Cut tops and tapered feet from sides, and plunge cut inside edge of uprights to save material. Use fence on saw to give a constant depth. Cut to internal corner but not beyond.
Step 2 Finish off internal corners using handsaw, supporting loose end of L-shape so it does not break away before being cut.
Step 4 Round all front-facing edges using 6mm rounding bit fitted to router. If you don’t have a router, round edges using electric sander.
Step 5 From remaining plywood above sides, cut 2 bottom blocks (B) with the bottom square and the top with a backwards slope of 2°. To do this, either set a mitre saw to cut at 2° off square, or you can do it by measuring 4mm up a side from the square end on 110mm-wide strip and mark in angle. Cut, then use this block as a guide to make angled blocks (C). Cut top blocks (D) with a square cut at top.
Step 6 Cut support arms (E), then mark 75mm down front edge from top of 1 arm and 350mm from back on underside. Join marks to give a taper and cut. Round underside of front corner with smaller paint tin, then cut curve. Sand lightly, then use this as a pattern for other 11 support arms. When all are cut, round all edges of support arms using 6mm rounding bit fitted to router.
Step 7 To assemble 1 side, place L-shaped side on a workbench, then glue a bottom block so it is flush with bottom and back, and slope on top edge goes down to back. Pin in place using two 25mm nails (block is set back from front edge of the side by 10mm).
Step 8 Place a support arm on side as a spacer, then glue and pin on first of angled blocks, making sure arm will be a snug fit and back of block is flush with back of side. Don’t glue and nail on support arm. Continue with same procedure by in turn placing a support arm then an angled block onto L-shaped side for remaining blocks. Finish with a top block after producing a matching curve at top front.
Step 9 After all blocks have been glued into position, put glue onto tops of blocks, then align and place an internal side (F) onto blocks, lining it up with bottom and back of the L-shaped side. Fix in place with a few nails. Mark out a regular pattern of screw fixing points so you miss support arm pockets, then predrill holes through side support and screw to block and sides using 50mm stainless-steel screws. Drive screws so heads are only just below surface of plywood.
Step 10 Turn assembly on its front edge and apply glue to backs of blocks. Centre back (G) onto side support and secure with pairs of 50mm screws at 200mm centres, screwing into sides, not blocks, so you avoiding screwing into support arm pockets. Repeat Steps 7-10 to make other L-shaped side assembly, but make sure it is a mirror image of first, so you have left- and right-handed sides.
Step 11 Clamp top cross rail (H) to backs of side assemblies, so they are 18mm down from top. Screw on from back using three 12G x 32mm galvanised screws for each joint. Repeat for bottom, using an offcut of plywood as a spacer
Step 12 With surf rack now freestanding, check all the arms will fit into their slots, then sand to remove rough edges and pencil marks. Apply 2 coats of clear exterior finish. Arrange support arms to suit.