FAQ Friday #47 - How do I know whether to have my inflatable boat tubes inflated or deflated when gluing parts on?

As a rule of thumb “if it’s holding air, stick things on with the tubes inflated and if it’s not holding air, stick things on with the tubes deflated”.

For example, if you have a hole in the tubes, whether it’s a pin prick or small mouse hole, you should fit the repair patch with the tube deflated. If you try to repair the leak with the tubes inflated the air from the leak will try to force the patch off resulting in an unsuccessful repair.

If you have a larger hole or perhaps a nasty gash and have to do a 2-stage repair with an internal and external patch (as detailed in our How to Guide), then you will need to undertake the internal patch with the tube deflated. Allow this repair time to cure and then once it’s holding air, fit the external patch with the tube inflated.

If you’re adding an item such as a snap davit, wear patch, handle or lifeline holder then you would install these items with the tube inflated as the tube is holding air. Some moulded fittings are pretty rigid and you may have to have the tube slightly softer than working pressure to ensure the full surface of the fitting sticks to the tube.

There are of course some exceptions to the rule of thumb. For example, during the tube fitting process when gluing a tube into a tube carrier at the transom - the tube is airtight but you would struggle to get the tube into the tube carrier if it’s inflated. This is obviously a much bigger task than a small patch repair and the best way to tackle this would be to glue the tube deflated (or at least not fully inflated!) and then working with a helper, one of you inflatable the tube and the other guides the tube into the correct location on the transom.

The same principles are the same for other inflatables too. One specific example I’ve been asked this week is about a paddle board, which is holding air perfectly well, but has more scuffs than the owner would like on one of the rails. They believe it’s from resting the board on the ground as both their SUPs have scuffs in the same place and they wish to add a protection patch before it wears through more and way ahead of it turning into a leak. And our advice on this would be to install the PVC patch with the paddleboard inflated (although you don’t need to go to full working pressure of 15+ PSI! – save some energy).

Hopefully this guide and the examples will help you work out whether you need to have your inflatable inflated or deflated for the work you’re looking to undertake.