Best Tool for Cutting Fiberglass Deck ?

[bazzer]

Do you have any experience of cutting a fiberglass balsa cored deck using a power tool? (MaineSail maybe?) I am about to re-core my deck on a 34 foot TrueNorth, about 50% needs doing. I am planning to cut to within a inch or two of the cabin and gunwale. Currently I am thinking of a small circular saw such as the Matika 4200. I don't think a router is up to the job. But if you have any suggestions I would appreciate reading about them.
Baz

[Weyalan]

You can buy router bits specifically for fiberglass. I have used one on my fibreglass / kevlar deck with no problems. I have also used an angle grinder with an appropriate cutting blade.

[Mark1977]

Sawsall with a multi purpose blade...

[Mark Johnson]

If you are going to recore the deck you want a narrow straight cut, so that when you lower that top half back down, the scar at the connect up which will show a bit, will look best.

For this, I think I would get the smallest blade version of a battery powered circular panel saw. (wear eye and lung protection). After you (preferably vacuum bag) back down the deck's top half, and fill the cut gap, I would dish out a 1" wide swath over the cut, and lay in perhaps two layers of glass tape, then fair it out... M.

[Sailmonkey]

I've re-cored a cockpit sole using a circular saw to cut out the surface of the deck. I'd buy a cheapo for this, as I wouldn't expect it to survive more than this job.

[bazzer]

Originally Posted by Weyalan

You can buy router bits specifically for fiberglass. I have used one on my fibreglass / kevlar deck with no problems. I have also used an angle grinder with an appropriate cutting blade.

Thanks for the reply, any chance of being more specific on the router bit and angle grinder blade?
Thanks Mate
Baz

[Catamount]

Assuming you're just trying to cut the top skin, and not all the way through the deck, you'll want a tool where you can set the depth of cut -- a circular saw works well, but is restricted to more or less straight cuts. I have used an angle grinder with an abrasive cutting blade, something like what might be used for cutting metal, but they don't work as well as the circular saw because they're harder to control. A router or roto-zip type of tool should work, but my experience using them in this application is limited.

[capn_billl]

I've used all three. Whatever you use buy a few spare blades. I would only use the rotozip for smaller cuts.

[foamcore]

I've done that job with a skill saw and it worked great.

[Bruce Bevan]

I also assume you are talking about taking one skin of the laminate off. I have worked beside a boat builder that uses some basic tools this type of work. For straight cuts on a laminate he has a circular saw that he made up himself. I am sure you could buy one, since he tends to make something rather than buy it, but his version has a 4 inch very thick carbide blade mounted on a smaller angle grinder. It has a cover and foot plate that is adjustable. This heavier blade has no problem chopping through the glass and it gets within an inch of an obstruction. Regular woodworking carbide blades dull up very quickly.

If you want to cut right through the deck then the sawsall fitted with a long carbide blade cuts through it like butter.

For fine grinding intricate crevaces a carbide bit in an air tool at times is worth its weight in gold. Tools can be round or square on the end. Much like router bits but built for the job and they don't dull easily.

Regular fairing you would use the small angle grinder with two thickness of sanding pads for stiffness.

The rotzip tool will work, but from y experience the blade will last a few inches before it dulls.

It shouldn't be too difficult to remove one side of the layup by cutting parallel strips then pulling them off by pound a large wedge/chissel between the core and the glass.

Remember to seal the new core with a hot mix of goop so it kick quickly. A slow kick will allow the catalyst to leech out into the wood and possible prevent a good reaction in the resin. On foam cores this may result in a softening of the foam.

Good Luck

BB

[Uncle Bob]

Originally Posted by bazzer

Do you have any experience of cutting a fiberglass balsa cored deck using a power tool? (MaineSail maybe?) I am about to re-core my deck on a 34 foot TrueNorth, about 50% needs doing. I am planning to cut to within a inch or two of the cabin and gunwale. Currently I am thinking of a small circular saw such as the Matika 4200. I don't think a router is up to the job. But if you have any suggestions I would appreciate reading about them.
Baz

Diamond blade on a small angle grinder works well AND lasts the distance. I use the continuous blade, not a segmented one.

[Blue Stocking]

Bazzer,

Take a look at my post under Teak Deck Removal, in the construction forum. It may help you.
Once you get past the apprehension, it not that difficult a job
You can cut curves with a Skilsaw. Make your first cut not much deeper the a score mark, used as a guide for your thru cut. I cut thru about 130 ft of 1/4" glass with one 60 tooth carbide tip blade.
If you are going to bevel both edges of the cut, and reglass, then a wider cut will give you a 3-point bond back to the core.

[cgaskell]

Harbor freight tool's knock off of the fein multimaster is good where precision is paramount, but the expensive blades and short lifespan of same would suggest using something like an angle grinder with a heavy carbide saw blade. I have used a dremel tool to do this kind of work, but it is far to labor intensive and the little motor generally packs up on the first day! Good luck!

[atoll]

best to use composite blades,available from bosch for jig saws.

also composite circular saw blades are available for cutting grp.

find thin steel cutting discs work well for straight cuts on grp with a small disck grinder,.

uk site but will help you identify what you need the correct blades last a long time as opposed to normal blades will burn out very quickly:

Introduction to Composite Cutting - diamond blades, diamond saws - tools for cutting glass reinforced material and carbon fibre.

[nv5l]

I'd stick with a skill saw, or worm drive, with the appropriate blade. I did mine with a worm drive and like the fact that they are thinner and allow you to get much closer to the edge you want to cut. Also, if you're right handed, you'll be looking at the blade as you cut, instead of having to look over the saw to see it. The trade off is that they're heavier and usually more bit more expensive, but well worth it.

Also, be careful not to cut too deep, especially if you wonder beyond the cored area. Otherwise you'll have a lot more work on you hands. That's where skill saws really come in handy, since you can set the depth of the blade and don't have to worry about cutting too deep and going all the way through. Routers also share this feature, but won't allow you to get as close to the edges, e.g., toerail, coachroof, etc...