Marine Snap Fasteners

Marine Snap Fasteners

Snaps for Canvas Boat Covers:  Pull, Lift or Twist?


What are the types of snaps used on boats?

Durable DOT style snaps are the most common snaps used on boat covers.

Marine grade stainless steel snaps are the most desirable, but nickel brass are also common and are fine to use.  

What are directional fasteners? 

Simply put, they are snaps that only come off in one direction.  With these snaps, you must perform an action in order to release the snap. Actions such as lifting from one direction, twisting, or releasing a positive locking mechanism are typical for these snaps.

Consider using directional fasteners when regular snaps might not hold tight enough and you are in need of a heavier duty snap fastener. 

Which snaps are considered directional fasteners? 

  • One way lift 

  • Lift the DOT

  • Pull the DOT

  • Snapfast

  • Q-snap

  • Twist style - Common sense fasteners, murphy, turnbutton

  • Positive locking - Perfix, Loxx, Stayput toggle

What are pull the dot fasteners?

The words Pull the Dot are stamped onto the outside of the cap of these fasteners to let you know you are looking at a directional fastener designed to be lifted from one direction.  

Although they look just like normal dot snaps, upon closer examination you will see the difference. If you flip the fastener over and look at the female socket side of the snap, you will see that the perfect circle has a flat edge to its ring. 

The two piece cap and socket Pull the Dot are designed to snap to a male Pull the Dot stud, either in canvas or fiberglass.  That flat edge on the female, catches on the exaggerated lip of the male Pull the Dot making it impossible to lift off unless pulled up from the opposite side since that flat edge is holding tight to the male.  

What is a one way snap?

Snaps are always a male/female mating system.  A one way snap means that the female will only lift off of the male in one way.  This can be accomplished by lifting it from only one side of the snap or by twisting or pulling up and squeezing one way.  This type of snap is key for keeping your snaps attached under stressful situations such as excessive wind or angles that would normally compromise ordinary snaps.

Which snaps are not directional fasteners? 

  • Durable Dot style snaps

  • Screw studs

  • Stayput bungee

  • Caf-Compo Plastic screw snaps

  • Snads

 Boat cover snap alternatives? 

  • Marine magnets

  • Lashing hooks

  • Suction cups

What size are marine canvas snaps (durable snaps)?


How do you put snaps on canvas? 

Some snaps, such as Perfix and Loxx, need special tools.

For the most common Durable Dot style snaps, you will need either a hand tool that squeezes and crimps the snap onto the canvas, or a hammer with anvil dies.  

Professionals generally use a squeeze style tool called a Pres-n-Snap.  It’s the easiest of the tools available.  DOT offers a hand squeeze style tool that is less commonly used.  There are also vise grip snap tools, some with detachable setting dies, that can be used for installing both the male and female snaps.  Some vise grip tools have the setting dies welded on.  These are only available with cap/socket (female side) for canvas. 

The hammer with anvil dies can work quite well and are economical, but remember that hammering cannot be done on your boat, and the 100% stainless steel snaps need to be used with high quality hardened steel anvil dies or the crimping action will quickly ruin the dies.  

Tip: Consider purchasing a professional Pres-n-Snap tool. As the owner of one of these handy tools, you will quickly become very popular at your marine! Being able to help your fellow boaters easily replace their snaps will have you invited to all kinds of fun stuff, barbeques, steak dinners, and cocktails. What a wonderful way to help a friend by just simply putting on a snap!