Kantun 2 Jib Retention Magnets

[Ian Self]

Anyone know where I can locate a UK supply of the tiny magnets used to locate the jib on a Kantun 2? The dimensions are 4mm OD, 1mm ID, 3mm thickness. SAILBOATRC.COM has them for sale on his website, of course, but relatively expensive and with associated shipping costs. I've found a supply in the USA, but again, although cheap ($0.69 each) the shipping costs are very high. I can't find a supply in the UK for such small magnets. I can locate 1mm thick ones (which I've ordered), and I guess I can stack these 3 up, but it's not ideal.

Any help would be appreciated

[Trevor]

Have you tried e-Magnets UK | Online Magnet Manufacturer and Supplier (e-magnetsuk.com) ?

[Ian Self]

I did try uk sources, but it seems the minimum diameter for neodymium ring magnets on the site you reference is 6mm. It's a bit frustrating.

[Eric Finley]

Pardon my ignorance but does this actually need to be magnetic? Surely this is just sliding into a fibre glass track?

If this is the case could you just use say brass rod 4mm dia and cut to length plus drilling the required hole?   A little more effort but a cheap easily obtained solution.

If it needs to be magnetic can you please explain.

[Ian Self]

I think you're correct, I don't think the locating rings actually need to be magnetic. However, where the rings fit, I suspect, is reinforced by an inserted metal strip, so that potentially assists in holding any magnetic ring in place (as well as the ratcheted slot). Any loss in efficacy would be minor by not using magnets, I guess. I had come to the same conclusion as you, but thought it was easier to locate a set of magnets than buy, drill and cut rod, as I didn't have the tools to do it accurately.  Searching for them, I discovered the issue, hence the original post.

[Eric Finley]

If there is a metal reinforcing strip I would have thought it would be marine grade stainless steel as you would not want it to corrode causing expansion and ultimately a problem with the fibre glass. If it is marine grade stainless it will not generally be magnetic, lesser grades (like used on a lot of cutlery) may well be magnetic.

Have you tried to see if a magnet sticks to the deck above the track?

Just interested as spend sometime at work looking at degrees of galvanic corrosion and corrosion for offshore platform use. (Salt water causes a lot of problems)

[Ian Self]

I just checked and any reinforcing within the glass fibre does not appear to be magnetic, as I had hypothesized it might be. So, the magnets seem to have been chosen because they are convenient - for the designer - and as you suggest, a rod of 4mm brass cut and drilled to size should work equally well. However, I did manage to get a few magnets from Croatia during lockdown, so I'm supplied at present. 

[Malcolm Appleton]

Eric,

The reason the K2 uses a magnetic jib pivot anchor is to make them easily retrieve them if/when the string breaks leaving the magnet buried in the slot.....

M