Thursday, August 2, 2012

The tablesaur (er, tablesaw) project

This is a strange post. I meant to do it on the garden. But life, as Robin Wood says (see his blog in the sidebar), got in the way. Now as readers of ths blog must know by now, I hate power tools. But I do a lot of metal work. And of all the aspects of metalwork I hate, cutting pieces if metal to shape is probably number one. You must, you see, use the hacksaw. A hacksaw works, and very well, too. But it is slow. Sometimes exasperatingly so. There are (ah, the Devil tempts you) alternatives. One alternative is an angle grinder. I do not own such an object. I do, however, own three powered circular handsaws. Well, one was given to me. Another was so cheap (under ten bucks) at a thrift store I couldn't pass it up. Ditto the third. So on one of these saws, a Makita in brilliant red, I attached an abrasive cutoff wheel. It is an excellent way to cut metal, but it is totally un-maneuverable. Makita-san has no blade guard (that's why he was so cheap) but that does not bother me. Only trouble is it is difficult to use, because you have to figure out how to hold the work somehow while you saw it.. Or grind it. Or whatever it is an abrasive cutoff wheel does.

So yesterday I had an idea. If I mounted Makita-san like a tablesaw, I would have both hands free . I happen to have some use for discarded circular saw blades. Can't say what it is, because recipients are reading the blog, alas. I need to cut up these blades, and Makita-san in tablesaw mode would do the job. So I went out to the shop. It was raining cats and dogs, or, as they say in Venezuela, raining palos de escoba y capuchinos de bronce, broomsticks and bronze capuchins (bronze capuchins: very heavy). No day for a walk, much less a bike ride. So in about an hour I had improvised a table saw.
What I did is take a found board, cut a slot in it, drilled (matching) mounting holes in the saw and the table, and bolted the saw to the board. Hard part is drilling holes in the saw, it is metal and hard to drill. Got to step-drill. Start out 3mm and work up to 6mm+ for 1/4"-20 hardware store bolts. Must countersink bolts on top surface. Circular saws have all sorts of obstructions to this program. There are pieces of saw sticking up just where you would like to put a bolt. The board is clamped to my trusty counterweighted Workmate. This thing has about 50 Kg. of logs added to it, so it will not tip, rotate, or walk off. From below it looks like this:
The strange-looking stick going off to the left is used to depress the trigger on Makita-san. A poor man's on-off toggle. I have since cut it off to a more reasonable length, say 30 cm. It would be nice if Makita-san had a trigger lock. But he doesen't. Note the heavy wood piled across the workmate. This makes the whole thing possible. 50 Kilos is not too much at all. Else the Workmate will tip over.

The hard part of all this is drilling the holes through metal and drilling matching holes in wood. My procedure is now to drill the metal first. From underneath, the sole of the saw. But (a) be sure and center-punch the hole (b) make sure you drill in a spot that is not occupied by some essential feature of the saw. Not as easy as it might be. You have to get a nut on the bolt, remember? If you can't get at the bolt it is a waste of time to drill. (c) Step-drill. Then set the saw in place and use it as a template to drill holes in the wood. Align it carefully with a centerline mark. Countersink these things from the top side. Bolt it in, and Robert est votre oncle. Clamps all the rest of the way.

Today, aided by experience, I went out and made another board just like the one shown here. This is the "wood tablesaw". Just like the one shown here, only with another saw. This will be used for wood. My son will use it far more than I will.

At least, as of this writing, it has stopped raining.