Okay,Plan B.........What kind of bit for dado?

[Mark Rios]

Since I have just determined, with your help, that I have a $200 door stop in the form of a Freud 508 dado set I need to go to my router table to do some rabbet's and dado's. I have done alot of edging (mostly roundover) and beading with my router table but no dadoing. Are there bits that are better than others for dadoes and rabbets? Not brands but styles or shapes? I will be needing to route/dado 3/4" dadoes and rabbets into plywood. Any bits last longer than others in plywood? Thanks very much for your help.

[Mike Cutler]

Mark. You don't have a $200.00 dollar doorstop. You'll use it someday, guaranteed.
For Dado's with a router, any quality router bit maker. Whitside, Amana, CMT, Woodcraft,Freud, will have a "straight cut bit" in the size you need. You need to make sure that the bit has cutters on the bottom, some don't.
By the way. This may be the time to get a MicroFence Jig, or maybe an edge guide system for the router to make the dado's. ;)

[Richard Wolf]

If you are making dado's in plywood for plywood you do not want a 3/4" bit. You will need a 23/32" and hope it works well. Ply is never consistant in thinkness, even from the same sheet. Some times a 1/2" bit and making two passes is more effective, but your setup time may get out of hand.

Richard

[John Renzetti]

Hi Mark, I found that the reverse helix cutters from Hersaf gave the best cuts in man made materials vs, the spiral and regular mortise router bits. The latter two seemed to give a better cut in solid materials. The Hersaf cutters screw onto an arbor so you can use the same arbor with multiple cutters. I had about 3-4 that were incrementally exactly or slightly smaller than 3/4". This way I got a tight fit when the sheet thickness varied.
Hope this helps.
take care,
John

[Larry Reimer]

I would use a spiral router bit and a couple of passes to get the correct width. John, I think your solution is interesting. Where do you find Hersal cutters? thanks

[Gary Herrmann]

For a 3/4" (or whatever the width of the ply really is) I usually use a 1/2" straight bit and make two passes. That said, I got a Freud Dial a Dado for Christmas and have been very pleased with it. It probably does take a little more setup, but if cutting a lot of them, it seemed to take less time overall - probably because I was able to use the TS fence.