Deck Hardware: Screws versus Bolts
About 1985 Tracker Marine started using self tapping “screws” to fasten down decks. At that time this was a new and different way of attaching decks to cross members. Competing boat builders lambasted Tracker for this “cheaper” method. It was claimed that floors would vibrate loose and boats would fall apart. Thirty years later the manufacturers who favor bolts prominently explain the method in their sales literature. But a majority of new boat builders now use deck screws and most rebuilders use screws regardless of what type of hardware was used by the manufacturer. Screws are easier to use. You hammer the self drilling head into the top of the wood and drill the screw through the wood into the cross member. You need a good strong drill, or air tool to use deck screws, a 1/4 HP home-use drill doesn’t have enough torque. It can be argued which method is stronger but deck screws have been used for thirty years on tens of thousands of boats. The prevailing opinion is that elevator bolts are strong but that deck screws are strong enough.
1 1/2” Elevator Bolt 1/4-20 bolt. Flat head won’t poke through carpet. Usually sold with self locking or flange nuts.
2” Deck Screw Phillips Head, 1/4-20. Flat head won’t poke through carpet. Self tapping, works best with aluminum cross channels.
With deck bolts you must drill a hole for the shaft of the bolt. When rebuilding you can try to drill from beneath using the old holes in the cross channels. To fasten deck bolts you must get under the pontoon to tighten the nut onto the bolt. In a production setting, as shown to the left and with power tools it isn’t much of a chore. But laying on your back on the garage floor or outside, it’s more difficult.
Deck Screws properly installed at a deck seam.
This image shows the proper use of deck screws where two pieces of decking meet. The black smudge is probably deck tape that has been compressed by the screws. When installing screws or bolts a chalk line is helpful in making sure you hit the cross channel.
Crest uses a unique cross member. It’s a rectangular box open on the top. It’s claimed to be a stronger system but like the deck bolt versus screw controversy, how strong is strong enough is debatable. When rebuilding a Crest Pontoon with elevator bolts, you need a longer (3”) elevator bolt. It goes all the way through the “box” cross channel. Or, you may use deck screws into the top of the cross channel but you have to be careful to hit the sides, not the open top of the box.
Crest Pontoon “box” style cross channel