Choosing saw blades for fiberglass

[bcooke]

Hi all,

I am getting ready to replace the core in my cockpit sole. I was going to cut out the top surface of the sole with my circular saw. Can I use an ordinary fine toothed saw blade or is there something better suited for thin fiberglass? I also am not sure how to get into the corners. I was thinking a small abrasive cutoff wheel that I already own. Any suggestions?

Thanks,

-Britton

[Dave, 397]

For cutting 'glass with a circular saw I use the cheapest nasty throwaway blades Home Depot has to offer...they're about 5 bucks a throw. Glass is pretty hard on saw blades, so the cheap ones have a considerable appeal. They're a rather coarse pattern, but that isn't a bad thing...a fine-toothed blade will dull out more quickly. The cut edge is pretty clean, and if it is a bit ragged, well, you're going to be doing some glasswork over that area anyhow, right?

My preference for cutting the deckskins off was a 5" x 1/8" cutoff disc pitched up in a HiSpeed-type body sander, which is one of my favorite tools in the shop. For tighter corners I used a smaller cutoff disc on a mandrel in a 90 degree die grinder (another very favorite tool).

Best,
Dave

[JetStream]

One of my favorite ways to cut a fiberglass skin is with a small abrasive wheel in my Dremel tool. It cuts very fast with extremely good control of cut angle.

[The Good Goose]

I may be exposing my ignorance but I was under the impression that the cockpit sole was solid glass. I have # 522 an east coast boat and I believe itis solid. I would think about just grinding the top layer of fiberglass and adding nidacore and glassing over that. I think it would be easier. My cockpit sole has alot of give but I think that is because it is under built not a bad core. There are plywood pieces glassed to the bottom of the sole but they don't form a continuous core. Just a thought based on my boat ; Yours' may well be cored but definately check it out before you start cutting.

Good Luck
Brock Richardson

[bcooke]

I have some cutting wheels for my air powered rotary tool so maybe I will pick up a dremel tool (everyone can use one, right?) and give that a try. A circular saw does seem pretty crude.

As for the coring... It is more likely I am the ignorant one. I thought late model Tritons were cored under the sole but I am never sure about those sorts of things. A knowledgeable surveyor mentioned it would need "recoring" when he was wailing away on it during the pre-purchase (#680). He might have meant "needs to have coring and a top skin added". The more I learn about Tritons, the more variations I find.

The boat currently has a steering column mounted in the forward section of the sole and I will be removing that shortly and can report back what I find beneath. The steering column has to go because I don't like the room it takes up, it blocks access to the top of the motor and shaft (original shaft seals - never touched), and I like tillers anyway. If anyone is interested in the column let me know before I advertise it.


Thanks for the input again,

-Britton

[Shark]

Britton,

Any chance you could have Tim post some photos of your new boat? Perhaps you could tell us how you found her etc etc etc.

It's raining outside again and I haven't sailed my boat in a week and a half!!

Lyman

[bcooke]

If you are asking me for my story then you must be REALLY bored :-)

Actually, with Tim on a cruise and me with no other way to host any pictures I think showing off my girl will have to wait. I only have survey photos at the moment anyway and they are all chronicalling what is wrong with the boat; hardly showing her in her best light. I am also a little sensitive about using Tim's pedestal to spotlight my own projects. This, afterall, is his showcase and I don't want to take anything away from that. Not that I think he would really object either...

I found the boat through one of the major web listings (Yachtworld...? I can't remember). It was a rather sad story. The previous owner loved the boat but had a stroke two years ago and it became apparent that he would never sail again. The boat sat for a couple of years in the back of a shed (collecting dust and mouse droppings) before being listed by a broker. I never met the PO as he was too upset about losing the boat to meet me. When I first saw the boat it was in the back of a storage shed shadowed by sparkling Hinkleys and such and the first thing I saw was a dusty bow poking out of the dreary depths with the name "Prudence" painted up forward. I had to smile because it felt like the boat was already trying to educate me by telling me to go slow. Prudence is definitely something I need! The broker wanted 10.9k. After a survey I offered 7. The broker wasn't too happy. I started looking at an Alberg 30. The PO decided he wanted to boat to go to someone who would fix her up. We settled at 8. Cosmetically, the boat looks dingy (PO believed in minimal maintenance) but is in sailing condition. I removed a twenty year accumulation of stuff from the cabin (along with crooked doors, leaking heads, mildewing cushions, etc.) The boat was only in the water for six weeks a season and stored inside the rest of its life so the decks are in pretty good shape. Most of the coring problems I have found have been the result of improperly mounted hardware (such as the steering pedestal).

At the moment, I am gringing bottom paint and will probably spend the rest of the summer taking care of the hull, replacing the broken mast support beam and the soft core under the mast, removing/repairing the cockpit sole and replacing the steering pedestal with a big access hatch, installing an anchoring system, sorting out the engine and setting up some basic wiring. Cosmetics, interior and systems will be on the multi-year plan. I am thinking minimalist cruising this fall :-) Obviously I don't have time to hold down a job which is why I am eating bread crumbs at the moment and working full time on the boat.

I usually talk about the boat for hours, boring my audience in the meantime, so I will leave it at that. Drop me a line and I can talk/write for hours.

As for tools... has anyone tried a Rotozip that I am seeing at all the Home Despots and Lowes? It looks like a dremel tool on steroids. I am not sure if it is too big to be really handy or just right to fill all my power tool needs.

-Britton

[Tony]

Britton,
A friend bought one for his powerboat rebuild, and said he loved it. In fact, it turned out to be the most used tool. I use my dremel with the extension and cutting wheel all the time, I think it'd be great, since the rotozip is indeed just like a beefier dremel with muscle behind it...at the price, you can't go wrong.

Fair Winds,

[Tim]

Britton (and all),

I am most pleased to host your photos and descriptions of boats and projects here. Please don't ever hesitate to ask. After all, boats (all people's boats) are what this forum is about, and each of us enjoys and learns from each other's experiences.

In any event, I am back from cruising (boo hoo).

Back to the topic:

I think that a carbide blade in your saw is always better for any task. They last a long time in fiberglass, and can be resharpened locally, usually for much less than a replacement. I believe that carbide is always worth the extra money.

I also have a Roto-Zip tool, which works OK. It's good for tight areas, but the bits don't last very long in the hard, abrasive fiberglass. Buy lots of extras. And then get more.

Note that in Nathan's #668, his cockpit sole has a balsa core--discovered much to the surprise of both of us this past spring. So Britton, your boat may well have balsa there as well, but do some exploring first to be sure. But we all know how different Tritons can be from one another, so nothing should be taken for granted. As I recall, your cockpit sole showed all signs of being cored.

[bcooke]

Yep, The cockpit sole is cored with 3/4 inch balsa. Or I think it was balsa. The coring looks more like something my mother used to force me to eat as a kid on cold mornings - some dark mushy stuff. After some drilling around I did find some white balsa (but still wet). Looks like a relatively dry week according to the forecast so I think I will start cutting tomorrow.

-Britton