Propspeed vs TBT for running gear

[accomplice]

We'll be hauling out to do our bottom in St Martin in a couple of months, and I've been thinking about what to do for our running gear.

When we were hauled out 18 months ago in NC, we had PropSpeed applied to the necessary bits. For the first year or so, all it took was wiping with a glove and it'd be clear again. Now the prop/shaft have some growth.

In the past I've tried a Cu/biocide-based paint on top of an epoxy barrier, and was unimpressed with both anti-foul performance and longevity. PropSpeed did much better, but was expensive and did not last as long as I'd like. I'd like to get at least 24 months out of the bottom and running gear anti-fouling, if that is possible.

Since we'll be where TBT is legal, is it preferable to use TBT or PropSpeed? Would a TBT based antifoul (such as ClearGear) do better or worse than PropSpeed in terms of how well and how long it resists growth?

I understand there are environmental considerations as well, but my question is regarding the performance.

[Jim Cate]

Good questions, Accomplice...

I have my doubts that TBT based antifouling will last any longer on your prop than the copper based ones. It will quite likely perform better as growth inhibitor while it lasts on the prop's surfaces, but my guess is that it will erode away just as fast as other paints.

We've been pretty happy with Propspeed ourselves. We bought enough for our prop from a friendly slipway for 30 AUD, and applied it according to instructions. Not at all difficult, despite what the 'authorized applicators" will tell you. It has been on for almost two years now, and is stilll somewhat effective. Not as good as when new, but growth still comes off with a gentle wipe with a green Scotchbrite pad.

I don't like Propspeed's business model... the common refusal to sell to DIY applicators in much of the world. Around the parts of Oz that we frequent those folks will charge upwards of 200 AUD for doing our small prop. This involves around 15 minutes of labour (plus some waiting for stuff to dry) and around 30 bucks worth of materials. I dunno if this is "fair" pricing for doing the job, but denying us the chance to DIY bugs me.

But despite this disagreement with business practice, it is the best stuff we've found yet for keeping your prop clean!

Jim