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Ed Edelenbos
 
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Default Steam bending basics??

I think the 1 hr/inch thick is pretty standard. A way I've seen it done
is to use a large pressure cooker with a copper tube through the lid
(the fitting that weight usually sits on comes out and a compression
fitting can be installed) then to a pvc pipe of the proper diameter with
a hole drilled in the cap. The pvc pipe is slanted downwards with the
bottom open. When it is steamed and still hot, it is attached and it
cools and dries in place retaining the bend. For larger pieces, most
people (I know) don't steam it. They attach it tight in the center (or
at one end depending on the curve) and then progressively (over several
days) tighten screws outward from that point.... the closer ones get a
turn or two a day and the farther ones get 4-5 turns a day. Sometimes
you have to start with oversized (extra length) screws and remove them
when they have served their purpose. Sometimes the process takes up to
2 weeks although typically it can be done in less time. For several
years in a row, I helped an older gent replace several (a couple each
year) mahogany "2 by" planks on his Owens 40+ footer this way.

Ed


William R. Watt wrote:
I've done something similar with a polytarp envelope but do not know how
hot it can get. What I got was warm moist air which was okay for the
gunwales I wanted to bend a bit more than they were willing to go dry. I
laid the polytarp on some plywood between two saw horses, put blocks a bit
higher than the camber of the bend I wanted at each end, laid the gunwale
stock on the blocks, folded the polytarp over, and "steamed" until I could
push the gunwales down to touch the plywood, put some weights on the
gunwales to hold them in that bent position, turned off the steam, and
left things like that overnight. In the morning I unwrapped everything and
had my bent gunwales.

"fraggy" ) writes:

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

fragged
"steamer" wrote in message
. ..

--Looking to see if someone's got a technique or guidelines to
follow; i.e. how long to steam a particular wood with a certain thickness.
Are there tables for this sort of thing?
--TIA,

--
"Steamboat Ed" Haas : Quando Omni
Hacking the Trailing Edge! : Flunkus Moritati
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---





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