Posted by a forum member a while ago I cant remember who! I found it most usefull. I have done my roof thining out with the Owatrol oil the instructions on the can say that you can thin the paint by 30%, I found that 10-15% was fine.
I have recently just repainted my NB, the previous owner had just kep plastering paint on top of the old paint and it was in a pretty bad way.
So i bought myself a palm sander (really quite quiet too and only cost £25) i decided to flat the paint off to almost bare metal in places, the dust was horrendous (and as i was sanding blue paint off i kept getting around ten comments from passing boaters that i looked like a smurf!!) you will be extremely surprised as to how much dust is created!!.
i started off by using the diy store type of sanding pads but at over £20 for a pack of three i resorted to going to a car body shop and bought two boxes of sanding pads (the velcro type) for £13 for a box of 50. i bought them in two grades one was 180 grit for the tough bumpy paint and the other was 400 grit for the light sanding between coats.
once all sanded down i used Rylards primer and undercoat, sanded back with 400 grit on the palm sander then wiped down with thinners, once this was done i got myself some dulux trade exterior gloss paint, cut a milk bottle down to use as a paint pod and mixed the paint with Owatrol oil to help the flow, i was painting my boat in mid june/july and it was absolutely baking, the Owatrol did the job but was still hard to apply the paint in the hottest of sun.
the method i used was to roll it on with a foam cheapo roller and then "feather" it off with a long bristled brush, lightly passed over the paintwork, then once left to bake on for a few days i buzzed it back with a 400 grit pad, wiped over with thinners and repeated over again until i had built up three coats, it is really important to let the paint bake before trying to put additional coats on.
The result now is a great looking paint job (far from professional but looks pretty damn good to me), as all will say its all in the prep work, i have never painted a boat before, infact i have only ever splashed a bit of paint on the walls at home, there is a video of a guy painting a boat on you tube but dont know how to post it on here, i followed this guys technique and it worked really really well
a few words of caution that i experienced
dont try and paint in the wind/snow/rain/megga hot sun
beware of the dust, youll be amazed at how much the sanding creates
use Owatrol oil as it was my lifesaver
dont use a cheap brush to "feather" off the paint
never ever use the diy shops sanding pads as theyll bankrupt you!! go to a car body supplier
wear a mask and be prepared to go home very very dirty/sweaty/covered in dust etc etc
Any questions PM me and ill try to help, i think my pics are on here somewhere of the before and after, if you cant ind them then just ask and ill send them to you
Good luck