Paul Diamond creates a specialised valve removal tool from a socket spanner in order to repair his inflatable tender
I had a hole in my 15-year-old Excel SD230 inflatable tender, and the first stumbling block to carrying out a dinghy repair was removing the valves to enable an inside patch to be applied, writes Paul Diamond.
To do a permanent and durable repair, it is better to first patch from the inside and then put a cover patch on the outside once the tubes are inflated.
A polythene bag can be placed behind the patch to prevent the tubes from being glued together when pressing and rollering the inside patch on.
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A 12-sided socket was easier to modify than a six-sided one. Credit: Paul Diamond
I tied a string to the bag so I could pull it back out through the valve hole once completed.
However, the plastic valve wrench bought specifically for this job snapped when I attempted to unscrew the valves from their seats.
I guess years of saltwater use had bound the valves to their holes.
The solution was to find a socket that fitted, in my case a 24mm one with 12 sides.
Using an angle grinder and a thin metal cutting disc, I cut six slots into the socket to align with the valve splines.
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Modified 24mm socket spanner was just the right size. Credit: Paul Diamond
Once the slots were cut the socket almost fitted, but was just slightly too narrow to fit over the valve internals.
So I ground out the internal edges with a Dremmel stone tool mounted in my pillar drill, and the socket securely held in a vice.
This took a bit of fettling to get just right, as I didn’t want to remove more material than necessary.
It would have been difficult to do this successfully with a hexagonal six-sided socket.
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Socket in use with a drive handle on the valve. Credit: Paul Diamond
I was then able to use a normal socket driver to apply the pressure needed to loosen the valve.
I found by holding the back of the valve and applying continuous pressure with the socket driver, I soon had the valve unscrewing.
I used garden wire to tie the valve backs near their holes, to save having to fish for them later once the repair was completed.
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