Router Bits For Plunging

[Flacjunky]

For all my past speaker projects I have always used a bit like this (double fluted straight bit) with my Jasper Jig for cutting the openings out.



I've seen elsewhere others are using a different kind of bit (up-cut or down-cut spiral bit) for the same purposes.



I'm about to invest in some replacement bits, which style should I be using to cut speaker openings in baffles?

[djg]

Up cut cleans out the kerf better but can splinter lumber and ply wood. MDF just needs a little sandpaper cleanup. I use a down cut spiral when routing the rebate edge and start with a very shallow cut. The hole edge is less critical if it is hidden by the speaker flange, as on a typical front mounted driver.

You visual aid states a down cut leaves a rough bottom edge, not in my experience. I have done 1/2" wide rebates by multiple passes with a 1/4" dia. down cut, leaving a smooth surface.

[Millstonemike]

I've only used a straight cut bit for the recess and the cutout on MDF, mutiple passes on both. Very clean cuts on all edges. The only issue is the it leaves the all the dust in the cut. My solution is to use a blow gun on a compressor to clear the cuts as I go (and I cut outside of course).

I can see where the down spiral bit will leave a clean bottom in a rebate but a rougher edge on the bottom edge of a hole.

[Whitneyville1]

I'm weird the other way. I prefer an up-spiral bit to clean the dust out of the cut (into the shop-Vac), and I get a very smooth bottom in either plywood or MDF, but it's a Whiteside bit too. I do my rebates with a rabbeting bit that has kie eight diameters and ten bearings, after I cut-out the driver hole. You can do it either way, whatever works best for you. I have had excellent luck with Katana solid carbide bits from MLCS too.

You might be "crowding" your router's HP with a little too fast a feed leaving the rough top and bottom. I noticed also, my spiral bits have a flat end flute on them, for what it's worth.

[a4eaudio]

I have used both straight and up cut spiral. The end product is about the same, but I prefer the spiral cutting bit because I can cut faster, in fewer passes and I think it would last longer (but haven't kept track enough to know if that is true).

[jhollander]

I like up cut the best but have used both. Upcut doesn't clog the groove or lift the router if I'm pushing it.

[dcibel]

http://www.freudtools.com/index.php/products/product/77-202

[Millstonemike]

http://www.freudtools.com/index.php/...product/77-202

Have your cake and eat it too ...