Attaching jig to cast iron bandsaw table. Drill and tap?

[Jim Barstow]

I have designed a jig to allow indexed cuts on my bandsaw for a project I'm working on. I'm stuck on how to attach it to my grizzly bandsaw table. There really isn't a good way to clamp it. I thought about using magnets but I'm afraid they might slip. Likewise for double sided tape. The most secure way would be to drill 4 holes in the table and tap them. Is this feasible? I have no idea how hard the table is and whether it is actually possible to drill a hole with a normal drill and bit.

[Bob Wingard]

Cast iron drills and taps very easily without any lubricant ... it is "self-lubricating". You might also consider just drilling a through hole, and using a bolt & nut. When you get ready to drill cast iron, make a TINY punch mark to locate the drill ... a solid whack with a center punch can easily cause cast iron to shatter.

[Phil Thien]

I drilled through holes (two of them) for holding my tall (resaw) bandsaw fence. The bottom of my fence has two t-slots routed in it, and I use t-bolts and knobs from the bottom. So I can reposition the fence, and tighten the knobs. Works great.

[Peter Quinn]

I'd tap them personally because its a very convenient and secure way to make a connection to cast iron, but through holes work as well. I think you have even less chance of the jig rotating with tapped holes, but if the through holes have very tight tolerances relative to the bolts it may not matter. I like to have a template to transfer hole alignment to both jig and table top, and to make sure my hole pattern won't go through any ribs in an iron table, and it helps to transfer center marks with a punch, then use a center drill to get things started before switching to your actual drill bit. Google "center drill" to see an example, most machine supply houses have them, they are cheap and add much greater accuracy to your metal drilling or tapping work. You can also use the correct size center drill to create a slight chamfer on the holes entry edge which minimizes burs on the tables surface and eases bolt entry. Well worth the money (cheap).

[Jack Parks]

If you have room to use two or more of the larger Magswitch magnets on your jig I don't think it will slip. It's amazing how well they hold. However, they are expensive at $35 each.

[jonathan eagle]

If you have room to use two or more of the larger Magswitch magnets on your jig I don't think it will slip. It's amazing how well they hold. However, they are expensive at $35 each.

I'm with Jack. They are very powerful.

[Bruce Wrenn]

I'm with Jack. They are very powerful.

Don't want to spend that much, then buy a couple of magnetic bases for dial indicators. Usually available for $10-$15 each. Adapt them to your jig. If jig sits to the right of the blade, then use Rockler's miter slot hardware to hold it.

[Gary Kman]

I drilled and tapped the outfeed bed of my jointer to hold a jig that holds the head for sharpening. 5/16" coarse I think. Easy as pie. Go for it.