Originally Posted by TDA  I have had customers tell me they have cut slots with drills but have never seen it or tried it. I imagine that it would require a very rigid system and more patience than I have. The one way this might work is if you had a drill made with a fishtail tip instead of the "V" style most have. Although this may put more stress on the tool and cause other problems.
Even if you have a perfect bit the drill may move back into the previous hole due to runout in the spindle or flex in the machine, table, material, or bit.
I assume you mean something like a PCB router bit. Where you have many grinding teeth to slowly take chunks out of the material. There are 2 problems with this. First cutting plastics with a grinding tool will almost always melt the material. Second, at those aspect ratios you still have the issue of the tool breaking taking even the smallest bite. Although I may not be grasping what you mean by a broach or sawlike blade.
With the information that we have I think Bigblokes idea has the most potential to get you what you need. Although if you can tell us more about what you're trying to do someone here might have more ideas or another way of doing it. |
I'm not at all an advocate of using drill bits to make a slot. I've gang drilled thick metal before to make cutting easy, but anything that really requires a thin slot is going to be important not to have ridged sides.
I meant a broach held from both ends under tension, like a more precise version of a scroll saw type arrangement. But as I said, that would require a through slot, which may not be what's needed here.
Given somewhat ideal geometry (ie the slots have open pockets on the ends) one could use a jewelers slitting saw but it's only in a very few circumstances.
Another idea might be to overcut the slot wide, planning for a second inserted piece to be fastened in afterwards. Not sure if that makes sense, but say cut the slot .1" + your slot width, then fasten a piece .1" into there, glue etc.