It's been some time since I read it, and I was paying attention to the
joining of plywood sheets along the edges, not patching a fiberglass hull.
What I read was "Gougeon Brothers on Boat Construction," and I watched their
video a couple of times.
That said, I still don't think it makes any structural difference.
Cosmetic? Yes, probably.
Roger
http://home.insightbb.com/~derbyrm
wrote in message
oups.com...
You mean your copy of West System book also says to put the largest
piece last. This is odd because this is the opposite of what I read in
the June-2004 edition of West System literature called "Fiberglass Boat
Repair & Maintenance". I have a feeling that they might have changed
their approach within the last couple years -- not sure.
As what your experience showed, we may encounter a small problem if we
put the largest piece last. We can sand away some of the largest piece
of fiberglass cloth if we don't put enough fairing compound to protect
the fiberglass cloth, and may reduce the strength of the largest
fiberglass cloth. On the other hand, if we put the smallest piece
last, we will only sand away the edge of the fiberglass cloth. I guess
that may be the reason why West System suggest putting the smallest
piece last. I guess I will stick with the approach that West System
has suggested.
Anyway, as what you have said, this probably doesn't matter much.
Either approach will be fine if we put enough fairing compound to
protect the fiberglass cloth.
Thanks for sharing your experience.
Jay Chan
derbyrm wrote:
On my first boat (a stitch and glue dinghy), I carefully read both the
Gougeon Brothers and System Three's directions and put the small tape
down
first with the larger on top. I did not put on sufficient fairing
compound,
so when I sanded, the wider tape was quickly cut down by the ridge at the
selvedge edge of the narrower layer. Since then I've been putting the
narrow tape on top. I really don't think it matters much.
Roger
http://home.insightbb.com/~derbyrm
"Ron Magen" wrote in message
news:t0Fmg.515$uo.477@trnddc07...
Jay,
I would re-read BOTH the Gudgeon Brothers literature and Don Casey's
book
.
. . carefully.
There are subtle differences between repairing a hole from the OUTSIDE,
or
from the INSIDE. It also depends on whether you are 'laying up' or
'repairing'. It sounds to me that you are looking at the the
instructions
on
pgs. 63 - 67, and the illustrations on pg. 65.
If you will note, the bottom sketch shows the ' . . .alternating layers
of
MAT and CLOTH.}. This is an exaggerated detail of the bevel that is all
around the repair It is a type of 'scarf joint' to give you the
strongest
connection between the 'skin' over the repaired / replaced core and the
remainder of the decking. If you are talking about STRUCTURAL
strength -
that depends on the repair you did on the core. When 'mat' is
mentioned,
it
indicates that there is some substantial thickness involved. Also, the
last
layer should be cloth. {followed by a couple of coats of Gelcoat or
some
other topcoating}
Regards & Good Luck,
Ron Magen
Backyard Boatshop
wrote in message
ups.com...
I would like to know the right way to lay down layers of fiberglass
clothes over a tapered edge of a fiberglass skin of a deck. Should I
lay down the largest piece first or the smallest piece of fiberglass
cloth first?
The balsa of the cored deck was rotten, and I needed to cut out the
outer skin of the deck (the outer skin was destroyed during the
process), removed the rotten core with good one. When I finally put
good core back in place, I will need to use epoxy and layers of
fiberglass cloths to replace the outerskin of the deck. I am supposed
to grind the edge of the sounding fiberglass skin into a tapered edge,
and then attach the edge of the fiberglass cloths over the tapered
edge
of the surrounding fiberglass skin.
The question is: Should I put the largest piece of fiberglass cloth
first and the smallest piece last like what West System has suggested?
Or should I put the smallest piece first and the largest piece last
like what Don Casey (author of "This Old Boat") has suggested?
I don't care which way "looks" best; all I care is which way can give
me the strongest deck.
Which way is the right way to me?
Thanks in advance for any info.
Jay Chan