Once again i thank you for all your very kind comments .
Got myself a little confused (easy at my age!) when i was posting it , as the cutting is 33" and not 39" as stated ! it is the backing that is 39"
Tomsunna, I have seen your work and it is only one cut at a time,,Go for it
Danny , Yes spiral blades the more i do the more confident i am with them!
Marg, you bet i was holding my breath
the cuts round the tail of the fish are very thin and as you will know with spirals it it very easy to cut through. The thin ply that i had on the underside is almost through so very close, but i am very pleased with the outcome
.....Pete