Hole saw lifespan

[bean438]

Looks like I will hunt down a circle jig for the router. I already have a router with a fixed base and plunge base.

Not to come across as an idiot but what do you mean by collars?

[Radian]

No worries I guess they go by the name of "bushings" as well.

Here's a quick primer:

http://www.newwoodworker.com/guidebush.html

[bean438]

Got it. I have heard of bushings before , but not collars.

[AntonZ]

Here's a simple DIY circle cutting jig for a plunge router (the "boomerang jig"). Very effective, several here have made their own version.

http://billfitzmaurice.info/forum/viewt ... =14&t=3714

Edit: link to another thread on circle jigs and pics of WB's version http://billfitzmaurice.info/forum/viewt ... 22#p137722

[rec]

I used to do mechanic work for a living so I own a set of MAC Tools hole saws. Its hard to say how may holes they drilled in metal way back when and they still go thru the braces for these speakers like butta! I stack my braces two deep on top of a scrap piece of wood and clamp to my bench. I just use my dewalt corded hand drill and I go right on thru. I do stop after I get thru the first brace and pop the plug out because its hard to get it out when its two deep. So if you want to continue using a hand drill get a good set of bi-metals like others recommended. They rock!