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Fabricate the Arches

—» Sort and stack your lumber so you have easy access. Material handling is most of the work and your back will thank you for every time you don't have to lift something twice.
Stack the lumber loosely, with lots of space between each piece to let it dry while you're working and also to discourage bugs, if you're working in the fresh air.

—» Always stack your arch pieces with the same orientation, even if it means an extra flip.
It's too easy to make a right cut with the board lying in the wrong position.

—» To make the first arch component, mark the three registration holes on the center-line. These 3 holes must be precise and vertical. With this template you will duplicate all the copies you need with no further measuring required. Drill these 3 holes ( some plans may show 4 holes ) to accept a 4" nail with a snug fit.
For larger lumber (awkward for a drill press), I take a ~6" 2x4 or 2x6, drill a vertical hole through it on the drill press and use it as a guide, holding it down on the long lumber, to drill a vertical hole with a cordless drill at the centre-punched holes I marked on the initial arch piece.

—» Triple check the overall and intermediate distances between holes that they match the plan. If the holes are precise and on the centre line, you'll end up with a good, strong fit.

—» Mark this piece so you don't get it mixed up with the following pieces and propagate errors.

—» Flip this piece upside-down (in case the registration hole isn't quite vertical, your copies will at least start at the right point) and use this pieces as a template. Place the template on another piece, just off the end. Align both pieces. Using your template, drill the first hole through the piece below. Drop a nail into the first hole drilled, so that when you drill the other two holes, they are exactly equidistant with no chance of misalignment.
If your wood is slightly warped (very likely), align it at each hole so that all holes are on the centre line, regardless how straight the board is.

—» If you're feeling cocky, drill all required pieces. If you're nervous, just drill 2 more boards.

—» Print a copy of your full-size template, check that the printed width is close to the dimension shown. Fold the edges so the paper can slide along your board, align the copy with your end registration hole and glue-stik it on your original template board.

—» Align the board with your chop saw blade to cut the angle on the right end. Cut along the edge of the printed hairline. (The bit trimmed off the top right is not critical)

—» With the board in the position where you cut the end, drill the closest registration hole right through into your chop saw bench.

—» Take the next 2 boards, pin them through the same hole and make the identical cut.

—» Flip the board left to right and upside down. Look at the drawing to make sure the orientation is right.

—» Pin the hole like in your last cut. Pivot your chop saw to the angle at that end and cut.

—» Lay the 3 pieces on the ground and pin them together into an "A", as on the left, to make sure that they fit together like they should, with a snug fit for the cross-beam.

—» When things line up nicely, drill and then cut the remaining pieces you require. Stack all the arch pieces so they line up together. Pin and glue them in pairs, one piece of each pair flipped left to right, and nail each pair together. It doesn't matter which piece is on the top or bottom, as long as all arch pairs are identical in orientation .

—» Take 3 of these completed arch members and bolt them together to form an "A".

At one of the two crossings, drill another hole about 4" from the existing one, on both sides.

Drop a nail or a bolt into each hole, remove the nail or bolt between them and, through the center of the crossing, cut through both arch members.

—» You now have the end of one arch, with a short piece and a long piece left over, which complete the other end of the arch.

—» Loosely bolt the arch components together. Stand up the arches, insert cross-beams into the triangles, stretch the arches a bit to allow the lap-joints to tighten up and drill the registration hole in each of the peaks to accommodate the carriage bolts.
If you haven't done it yet, you can also trim the arch peaks at this time.

—» Set up the arches symetrically so that each arch is the mirror image of the other.

—» Should you decide on a railing, make the cross-beams one foot longer on each side. This will give you a foot of lumber on each outside, to brace the posts with left over scrap.

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The design and construction techniques presented on this page are protected from patents by prior art & copyright and I reserve all rights regarding this design. Feel free to utilize this information for personal use but applications involving the exchange of money, require my approval. If you'd like to build bridges for profit, I'd be happy to help you. :-) Frank Petersohn