I believe i am going to need to purchase buoyancy bags for 1018 as she does not have any buoyancy at all. there is no bow tank either. so any suggestions on how much buoyancy i am going to need? i know ill need an extra large bow bag, but what size do i get for under the decks and how many, remember she is a IXb so i would like to tuck them under the decks so i have more room to manouvre. do i get long skinny ones? who else supplies them, i know P&B do.

look equipment for sale then various bits someone has some there.

you racing this weekend?

You need a large triangular bow bag and two large pillow bags each side near the transom, mounted low to help lift the boat if swamped too high and the stern sinks too much andyou will never get the water out, Crewsaver were the best once upon a time, Holt white bags were/are a bit fragile.

i know that all the newer boat, tales, NSM's all have the pillow shaped ones at the back, but i was wondering if i could get sausage shaped ones to tuck under the decks, if that is feasable or buoyant enough?would there be enough buoyancy in the sausage ones or would i need 2 down each deck?

what you need is Crewsaver B/Bags:

Standard Bow Bag - 36" x 30" x 12" - 136L wait for it......£59.95!

& 2 or even 4 x 48" x 8" @ £31.95 a piece ....ouch

or speak to someone like LDC Racing Sailboats who do a Holt cheaper version but not as durable.

When I aquired my first Merlin 1805 this too had a bloody great bow bag and but smaller sausage shaped bags located just under the side decks.

im leaning towards the standard bow bag and 2 (30x9) bags in the stern. is this enough buoyancy? thats already putting me down #110.95.
the 2 (30x9) bags should tuck in nicely under the stern decks.

I have a large crewsaver bow bag going spare I will dig it out and check it over if its any good you can have it. 
If you can keep the holt pvc bags away from screw heads and sharp objects they do a good job but in my view the proofed nylon type are a far more robust bag and offer the better longterm solution even at the extra cost.

Yep suppod to be racing although the weather looks a bit iffy (cold, no drysuit!) See you there if you fel like a beer.

Marinestore were the cheapest for buoyancy bags by mail order