"fraggy" wrote in message
...
hi
my boatyard puts the wood in a long bag made from sail cover material and
inserts the steam cleaner lance and just leaves it on full blast for about
1
hour per inch

Pioneer was planked using what has been termed as "boil in the bag"
steaming.
http://www.pioneersailingtrust.org.uk/
Plank is wrapped in a sewn up tube of cheap tarp and steamed (about an hour
per inch) but the plank can be clamped to the boat
while steaming and eased into shape as & when the timber will.
Then left to cool before releasing the plank to remove the bag (which can
often be reused)
Makes good sense to me and must be lass prone to failiures than rushing to
fit the plank in the 5 mins it takes to cool when removed from a steambox.
I know a guy here in the uk who is about to try this on his 40ft smack
might take a tinnie or two and watch ))