Evan,

Don't try to cut to the hull surface on the first pass. The gain is not
worth the risk. As you will probably be working blind for part of the
cut. It might be best to cut it down, then clear it out.

If you don't want to buy tools:
Use the jig (saber) saw to cut as closely as it can, then go in with the
angle grinder and any wheel (course) at all. This should get you so
just the tabbing remains and you can clean that off with a sanding disk
on the angle grinder.

If you want to buy one or more tools:
The suggestion of a Fein Multi-tool is good for lots of strange
fiberglass boat work. It can do this, but it will not be fast.
A reciprocating saw witn a long blade would allow you to flex the blade
so it lies against the inside of the hull. The machine will be back
from that area of interest so your visability will be good. The saw can
be controlled to leave just a little of the tabbing radius. This is the
method I have used on more than a few jobs.

Good Luck - from another NA-ME that now makes a living at this stuff.

Matt Colie www.southpointechandler.com

Evan Gatehouse wrote:
I am going to trim some plywood frames that intersect the hull right at the
shoulder position of a few quarterberths. These are either 1/4" or 3/8"
plywood frames, tabbed both sides to the hull. By the way, I'm a naval
architect and mech. engineer so I have a pretty good idea of what I can and
cannot cut

I can cut down into the glass with a jigsaw, but the baseplate of the jigsaw
will bump the hull before I get close enough - and I would like to run the
cut line right down the hull for about 12".

So the tools I have available a

- angle grinder with cut-off wheel
- dremel tool with fiberglass cutting discs
- jigsaw

Any other tools that might work for a tight cut against the hull through
fiberglass tabbing? The only other one I can think of is a reciprocating
saw ("Sawz-All") but they are a bit hard to control and still get a nice
close to the hull.

I recognize I'll have to do some grinding / sanding of the last of the
tabbing but would like to minimize the amount of this.

Evan,
I had to reposition a couple bulkheads on my 32' Traveler becasue of the
previous owners bad (IMO) layout.
I went thru a short learning curve on how much glass dust I could spread
around the entire interior before I stopped grinding the tabbing.
Then I took the base plate off my jig saw and was able to get pretty close
by using a thin blade and making it bend to run parallel to the hull, slow
and broke a few blades.
I ended up using a sharpened up old wood chisel to cut the tabbing and get
the bulkhead out, and get some of the tabbing off the inside of the hull,
minimizing grinding of the remainder.
MMC
"Evan Gatehouse" wrote in message
...
I am going to trim some plywood frames that intersect the hull right at
the
shoulder position of a few quarterberths. These are either 1/4" or 3/8"
plywood frames, tabbed both sides to the hull. By the way, I'm a naval
architect and mech. engineer so I have a pretty good idea of what I can
and
cannot cut

I can cut down into the glass with a jigsaw, but the baseplate of the
jigsaw
will bump the hull before I get close enough - and I would like to run the
cut line right down the hull for about 12".

So the tools I have available a

- angle grinder with cut-off wheel
- dremel tool with fiberglass cutting discs
- jigsaw

Any other tools that might work for a tight cut against the hull through
fiberglass tabbing? The only other one I can think of is a reciprocating
saw ("Sawz-All") but they are a bit hard to control and still get a nice
close to the hull.

I recognize I'll have to do some grinding / sanding of the last of the
tabbing but would like to minimize the amount of this.

--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

"Robert Larder" wrote in message ...
Never tried it, but how about a Fein Multimaster with a cranked saw blade?

Evan Gatehouse wrote:
I am going to trim some plywood frames that intersect the hull right
at the shoulder position of a few quarterberths. These are either
1/4" or 3/8" plywood frames, tabbed both sides to the hull. By the
way, I'm a naval architect and mech. engineer so I have a pretty good

If you don't have a whole lot to do you might try a fairly coarse
hacksaw blade in a vicegrips.Put the vicegrips on the end to make it a
"pull" saw to keep the blade from bending.

It's the only halfway good thing i've ever heard aout those tools.

Glenn Ashmore wrote:

Jim Conlin wrote:
... and don't be tempted by the other detail sanders on the market (Bosch,
Porter-Cable, Ryobi). I agree with Glenn's conclusion that they're only useful as
a sexual aid. I have a couple that i'd let go cheap. They've only been used as
sanders.

D&@N, your words live on the web for a long time. :-)
--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Evan Gatehouse" wrote in message
...
fiberglass tabbing? The only other one I can think of is a reciprocating
saw ("Sawz-All") but they are a bit hard to control and still get a nice
close to the hull.

I've used a reciprocating saw to cut both fiberglass or steel in similar
situations.

The good quality long blade will flex enough to allow you the clearance you
need for the saw against the hull. It is however, hard on the saw since it
causes a side thrust that it is not built for. The cheap saws have only alum
or plastic guides that wear quickly.

Blades will also dull quickly, what ever method, because of the glass
fiber...I a long cut in 1/8-3/16" material I have seen the teeth wear
completely off in a foot or so. Not a cheap project when blades cost $2
each.


--
My opinion and experience. FWIW

Steve
s/v Good Intentions

"Evan Gatehouse" wrote in message
...
I am going to trim some plywood frames that intersect the hull right at
the
shoulder position of a few quarterberths. These are either 1/4" or 3/8"
plywood frames, tabbed both sides to the hull. By the

Just a thought. If these plywood frames were installed using good
fiberglass/marine practices, the would be a strip of foam between the edge
of the ply and the hull. Among other thing, it also forms fillet for the
tabbing. If your lucky and the builder put this foam strip in, then you can
just grind the glass down with the edge of a cutting wheel, until you get to
the foam, same on the other side. Cut ply perpendicular to the this kerf and
break it off in sections.

Good luck.

Steve
s/v Good Intentions

Thanks to all for the brilliant suggestions. We do have a Milwaulkee detail
sander that does a very good job as a detail sander. The cost of the Fein
was hard to swallow at the time I bought it (it was a Christmas gift FOR my
wife). So buying a Fein for what is likely to be a one time job seems tough
to bear. I can always get one if the other suggestions don't work.

I liked the "jigsaw without baseplate" and the use of wood chisels to remove
the tabbing and I'll try them.

I also bought lots of plastic sheeting and a shop vac in anticipation of
this being ugly.

For a cautionary tale - on my last boat I had one or two spots where the
tabbing was loose. Being a bit over-cautious I ground off ALL the old
tabbbing and re-glassed bulkheads and furniture wherever I could find them.
Made me confident with the boat's structure. But I don't really, well,
really _enjoy_ grinding glass as much any more... Working in tiny lockers
was the worst.


--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

I did the first frames yesterday. Only required about 18" cutting each
side. It was an education in how tough a simple polyester laminate can be.
I cut the top and bottom of the frame and used a Dremel tool (with a right
angle attachment) to cut the tabbing on one side. Didn't cut into the
plywood because the cutting disc is too small.

I hit the piece of wood framing with a 2 lb hammer. Bounced off. Hit it
repeatedly and it bounced off. I then cut the tabbing on the other side and
had to literally pry the ply frame off in chunks with a prying tool and a
chisel.

I had a strip of raised tabbing each side of a putty fillet that I ground
down with an angle grinder and 24 grit disc. It was an o.k. job until the
angle grinder got going and threw dust everywhere as usual. I hate angle
grinders for this reason.


--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

Glenn Ashmore wrote:

Evan,

You really should invest a couple hundred bucks in a Fein Multitool and
an offset carbon steel blade. It will cut glass right up flush with the
hull and sands better than any of the other tools I have. It is by far
my favorite power hand tool.

I've found that the carbide tile-cutting blades also make short work of
fiberglass and it won't dull them.

Fein Multimaster has a cutting blade attachment that can plunge cut.

--


Keith
__
Live your life so that when you die, the preacher will not have to tell lies
at your funeral.
"Evan Gatehouse" wrote in message
...
I am going to trim some plywood frames that intersect the hull right at
the
shoulder position of a few quarterberths. These are either 1/4" or 3/8"
plywood frames, tabbed both sides to the hull. By the way, I'm a naval
architect and mech. engineer so I have a pretty good idea of what I can
and
cannot cut

I can cut down into the glass with a jigsaw, but the baseplate of the
jigsaw
will bump the hull before I get close enough - and I would like to run the
cut line right down the hull for about 12".

So the tools I have available a

- angle grinder with cut-off wheel
- dremel tool with fiberglass cutting discs
- jigsaw

Any other tools that might work for a tight cut against the hull through
fiberglass tabbing? The only other one I can think of is a reciprocating
saw ("Sawz-All") but they are a bit hard to control and still get a nice
close to the hull.

I recognize I'll have to do some grinding / sanding of the last of the
tabbing but would like to minimize the amount of this.

--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)