On Sun, 30 May 2010 21:05:11 +0100, Barnett22
wrote:


'Bruce[_22_ Wrote:
;799374']On Sun, 30 May 2010 01:52:13 +0100, Barnett22
wrote:
-

I came upon a nice Bass Boat (ha ha) on a bad deal. It has several
cracks in the hull and is taking on water. I have turned the boat
upside down and have sanded the hull. The places where the cracks are
I have sanded down to the fiberglass. My plan is to drill holes in
the
bottom where the hull seams to be weak and inject with injection foam
and then re-fiberglass the whole bottom. The I plan to use "work
horse" Illiminator fiberglass resin to spray the bottom for blocking
and repaint with Imron single stage paint. My question is; will the
fiberglass bite to some areas where there is still gelcoat left on the
hull or do I need to go all the way to fiberglass all over? Any ideas
or comments will be appreciated.........Thanks-


I am assuming that your boat is a single skin, i.e., not a foam
sandwich, construction. If that is correct and you have cracks that
penetrate the hull (you said they boat was leaking water through the
cracks) then your intended repair is not going to fix anything, at
least not for very long. The normal procedure is to grind out the
crack and fill with layers of fiberglass cloth and after you have the
repair filled to the same thickness and the hull, sand smooth and
finish.

Go to http://westsystem.com/ss/boat-repair/

Boat Repair

These Epoxyworks articles are about specific boat repair, restoration
or related projects. For comprehensive boat repair and restoration
instructions, download one of our comprehensive manuals: 002-970
Wooden Boat Restoration & Repair, 002-550 Fiberglass Boat Repair &
Maintenance or 002-650 Gelcoat Blisters-Diagnosis, Repair &
Prevention, published by Gougeon Brothers.

Click on the link titled "Fiberglass Boat Repair & Maintenance" and
download the manual and read it.

It gives sufficient detail that you should have no problems but if you
do then come back.

By the way, gel coat is essentially polyester resin with a coloring
agent which is used to make a smooth finish on the outside of the
fiberglass structural layer. So, since it is just a surface finish it
should be ground completely off in the areas that you are bonding
additional glass.

You say that "The I plan to use "work horse" Illiminator fiberglass
resin to spray the bottom for blocking..." I am not sure what you mean
here but a layer of epoxy resin on the surface of the hull will
provide some waterproofing but will not contribute significant
additional strength.

If you meant that you intend to use epoxy resin as a filler and base
coat for the finish paint coat then I would suggest that you use a two
part epoxy :high build primer" as it will be a much better base coat.

Thanks for your help. I am guessing I will need to cut out the bad
fiberglass, bevel back the edges and replace with layers required to
match thickness. Yes, there are places on the boat that are
"sandwiched". I am very concerned about not completely glassing the
bottom of this hull. I have ordered biaxial cloth, Resin and slow
hardener. I do have about 6 (not sure what to call them) ridges, water
runners, reveals?.?. that I would have to go over if I re-glass the
bottom. I am sure if I use 8-10 lb fabric and layer it, it wouldn't be
a problem. here is a photo of the only large problem areas.....these
are photos from when I started.......some yahoo worked on it before I
got it. I will post photos as I go.......Thanks again


I would recommend that you repair any cracks or deep gouges as these
would detract from the strength of the hull. Then if you want to you
could sheath the entire bottom of the boat with a layer, or more, of
cloth. However, that is going to be a big job as you will have to
grind off all the gelcoat, which is not a small job.

You might try to determine if the cracks are a matter of hitting
something or structural weakness. Is all the damage in an area that is
unsupported by stringers or ribs? If there is a large area where the
damage is that has no stringers, bulkheads or ribs, or if the bottom
is flexible in the damaged areas, and there is no damage in areas
where the hull does have inner supports then it is possible that the
hull is just not stiff enough in some areas and adding stringers or
ribs, inside, may be a solution. Simply adding a layer of glass will
not reduce flexing to any great extent.

(I believe that it is 10 oz. cloth, not 10 lb. :-)

Here we would consider 600 gm. (per square meter) heavy cloth. If I am
calculating correctly your 10 oz. (per square yard) is about 300 gm.
what we would consider a medium weight and depending on weave would be
commonly used.

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)