OT: Learning and rocks...

[Samiel]

Sorry for the OT post, but I have 2 questions, one kind of related, the other not so much...

1. Where would you recommend learning the basics of woodworking? I live in the Dallas/Ft. Worth area (Arlington actually). Do junior colleges generally have some classes? Maybe Home Depot or Lowe's might have classes? I'm not sure where to start to tell you the truth.

1. I recently acquired some geode-type rocks. Unfortunately, they need to be cut in order to see the inside (duh, right?). What type of saw (or other equipment) would be needed to cut through rock? Someone here mentioned that a "wet saw" would do it, but I'm not familiar enough with any types of saws to know.

Thanks!

- Samiel

[Charles Spitzer]

2: ask a tiler; they have wet saws. you can use a masonry blade in your skilsaw. geodes can also be cracked with a cold chisel and a hammer, and i've seen a tool that looks like a strap wrench but has a length of chain instead of a strap used for this.

[U-CDK_CHARLES\Charles]

If the geode is too large for a tiler, someone who fabricates large stones (countertops, large pavers, slates . . . ) will have a suitable saw.

[Andy Dingley]

Take it to a graveyard monument maker. If you want it as a decorative piece you'll be wanting a good surface, and a neat cut is a lot easier to polish.

You _can_ cut it with workshop tools, but geodes are too large for a wet tile cutter and a dry diamond disk in a 9" angle grinder isn't very smooth.

[Eric Ryder]

The saw you want is a lapidary saw. I happen to have one given to me - diamond abrasive blade, maybe a 4-5" wheel, < 1/4 HP, water cooled, fixed table, etc.

[Paul O.]

There are rock saws available at lapidary shops for doing this type of cutting, but they are expensive. If you have a lapidary shop near you can ask if they will cut them for you, for a fee of course, or maybe they know of someone who will do it.

[George E. Cawthon]

If you just want to look inside, whack the rock with a hammer/sledge to break it. If you really want to cut it so that you get a smooth surface, you need a rock saw. You will need at least a 10 inch saw to cut a 3-4 inch diameter rock. These will use a diamond saw and oil for a cutting/cooling fluid. A new 10 inch saw is going to cost in the neighborhood of $800-$1000. Even an old saw is likely to cost at least $200 and you may need a new blade which will be around $100. So unless you are serious, don't expect to buy any equipment. Check with your local lapidary shop, most will cut rocks for a specific fee per square inch, and with the local rock and gem club. Cutting rock such as agate (quartz) is fairly slow and requires a vice to hold the rock and positive advancement of the vice holding the rock. Otherwise, you will likely ruin the blade or yourself.

[George E. Cawthon]

What you have is called a trim saw and is used to cut thin slabbed material, maybe 1/4 to 3/8" thick. Maximum cut depth would be about 1 inch and that would be rather slow cutting.

[Kevin Singleton]

If the local community college doesn't offer classes, check with the local high schools. Some still have shops, especially the older schools. They may offer adult courses at night. You can also take classes at Woodcraft, in Farmers Branch, most weekends. There's a good rock store right next to Wood World, in Richardson, that might have the saw you need. They'll certainly be able to help you, and they've got some great stuff.

[Grant P. Beagles]

In answer to #1 - Try Woodcraft in Addison or Ft. Worth. They both offer a selection of classes. I have taken a few at the Addison shop and have been really impressed.

Grant

"George E. Cawth> Eric Ryder wrote:

[Samiel]

Thanks! I looked at the Woodcraft website and it looks like they offer many weekend classes (though I'm sure it would add up really quick).

- Samiel

[Samiel]

Interesting thought. I may be having a house built soon, so maybe one of the construction guys will have something to do the job.

- Samiel

[Rick Samuel]

[Andy Dingley]

No, they won't - not unless you're having a granite hearth installed.

But they'll think they have something, and then they'll try cutting it dry. This will be a mess.

[Samiel]

I'm having granite countertops installed... does that count?

- Samiel

[Andy Dingley]

Maybe - but you want a wet saw that's big enough to saw it in one pass. If they're cutting on site, or else whoever is cutting the countertop, ought to have something.

[Joe Gorman]

Those are usually cut in their shop, with a really neat saw. My BIL has one. Fun to watch. The counterscan be cut onsite if necessary, I had to cut down the cabinets under the counter because someone didn't allow for the base molding when he measured for cabinets and countertops. Didn't get to see the countertop cut but after watching in the shop I can only imagine the mess onsite. Joe

[Charles Spitzer]

they may trim with a 4" wet saw with a diamond blade, but the saws used to manufacture countertops are large flat bed saws and are not portable. the ones i've seen are 15'x30' or so.

a 10" wet saw will cut 4" or so. you can get a 7" wet saw for

[Prometheus]

I've never cut open a geode, but I've done a whole ton of ceramic tiling, and there are two other inexpensive methods you could try. The neandertal way of cutting tile is to use a carbide scribe to score a line, and then break the tile with a specialized pair of pliers. This might work if you score a line on the rock, and then carefully place a cold chisel on the scribe line and tap it with a hammer. The other option you could try is getting a rotozip carbide tile cutting bit (I use them in my dremel tool, no need for the rotozip, really) they work swell for cutting round holes in tile (for the knobs and spigot, mostly) and they might just cut a rock, depending on how hard the sucker is. Just don't apply too much pressure, and let the bit cool down every so often. Those tile cutting "blades" in the above post are not worth the effort involved, IMO, but you may have some luck with them if everything else fails!

[Rick Cook]

Keep in mind that quartz (geode material) is a lot harder than most tiles. The right way to cut one open is to use a large rock saw which uses a diamond blade running in a bath of oil-based coolant.

You can cut one open with a tile saw, if you go slow and use lots of water -- usually.

Also keep in mind that these things sometimes have stresses in them that make them break when you try to cut them.

--RC