Sailfeed
July 22nd

A little bit about hose clamps

Posted by // July 22, 2012 // COMMENT (0 Comments)

Maintenance,

How much do you know about hose clamps? How much do you want to know? It seems the subject is a bit like Alice’s rabbit hole- though it doesn’t have quite the same charm you can go as deep as you like…

After pulling dozens of the hoses in my boat the one thing I feel I can say with confidence about hose clamps is that these are tricky little beasts. You can never seem to get at the screw if the tail is where you want it and when they’re installed almost invariably whatever part you can’t look at is the most likely bit to fail. Often this is the screw, hidden in its casing, or the band itself, on the underside of the hose where moisture gathers out of sight.

Though it looks fine this band snapped from hidden crevice corrosion

 Most of the hose clamps you encounter, and hopefully all in the marine world, will be stainless steel. Even so corrosion is nearly always their undoing, it is just a question of time. Occasionally the screw will be of lesser grade stainless, and far more susceptible to corrosion. This screw can even be of a different metal entirely, leading to many clamps being labeled ‘All Stainless’  or some variant of this. I think this labeling may be a bit archaic though, as I have bought quite a few all stainless clamps which didn’t explicitly state it.

As for the clamps themselves, there are a few variations. Most common is something like this:

A standard all-stainless steel hose clamp

Significantly more expensive, but commensurately better, are embossed hose clamps. These have a solid band throughout with embossed threads and are much less likely to snap from corrosion. Being pricey, they are also reliably well-built and beefier than a standard hose clamp.

No holes in the band – great on thru-hulls.
 The one in the foreground is the ‘embossed’ clamp. It is beefier and 
 better constructed than more common variants (background).

Here’s a neat feature – I like this little enclosed screw head a lot (the one on the right). 

This helps keep the screwdriver in when you’re poking around in small spaces. Unfortunately all of this particular brand had seriously corroded screws, likely of lower grade of stainless.

As for thru-hull connections it’s worth noting that where people used to recommend double hose clamps on all below-the-waterlines connections this is increasingly being reconsidered. A well-installed hose clamp is extremely unlikely to fail and on some fittings there isn’t room to properly install two. In these cases insisting on the practice can cut or damage the hose. Of course if there is space for it a second clamp will add some security but better than using two at once might be to use one and replace it after a certain number of years (As for how long I expect many of mine were in place for decades, and less than a third failed when I removed them).

Well, that’s only a bit about hose clamps but I think just the basics are enough for me! Oh, and by the way, I’m going to launch the boat on Thursday. Weather permitting, that is.

This article was syndicated from Safe At Harbour But Meant For The Sea: DIY Sailing with Paul Calder

Leave a Reply