sorry for the delay in replying Dave (work commitments) and thanks for the advice I particularly like the three prop idea. I have a problem in as much as I love doing things for the sake of it and this opens up an opportunity.

Thanks again mate

HI Mick
Just seen your post.
You can reverse a brushless by changing any two of the three wires between the ESC and the motor. However I would not wish to try this until the motor was stationary. As you will be switching whilst the motor is stationary there will be no currentso with a small motor 10 amp switches should suffice.
How you identify that the motor is stationary may not be simple.
As you are aware there are reversible brushless ESCs but most are designed for model cars and they apply the brakes before you can select reverse so its a two push process on the tranny stick. it doesn't always work and mine sometimes seem to have a mind of their own. The more expensive types designed for model boats do seem to be more controllable.
As you are building a Vosper, many had two props and you could add a third with two for forward and one in the centre for reverse. You would need three motors and ESCs (Giant Shark have a sale on at present) but they could all be plugged into one channel so a single stick would control fwd & reverse with centre off.
Good luck with whatever you decide. Please ask if you need more help or advice
Dave

HI
I was given the one I currently have and was going to buy a brushless motor, I am quite new to the hobby and I do have a couple of 540 brushed motors with ESCs. I was thinking of using micro switches to reverse the polarity but these would need a high rating. I take your point about price of a new one I could get a motor and ESC. for £35-£50.
I am building a hull based on the Ron Rees amazing hull design but I have made it with the lower chine curving up at the front and and flared in a convex curve if that makes sense.
This makes it a bit Vosper MTB/ASRL looking so I would like a slightly lively performance without being too fast.
I may submit a build blog on the hull which is 24"x 7"

HI
can you a bit more details of what you want to do. Yes it can be done but why would you as a frw/rev esc cost less then £20.00
pm if you want some help with this