Limitations of a Router Table for Making Mouldings

Buying a second-hand shaper is a wiser choice than trying to stretch your router's capabilities too far. April 26, 2006

I've just tried a crown moulding bit on my router table because I want to make my own moulding for my kitchen cabinets. I've found out that because the bit is longer than other bit, it creates vibrations on the router. I tried to reduce the speed, but it didn't work. I'm thinking about adding a shaft over the bit, screwed into the fence, that would hold in place the other end of the bit. There's a small cavity on the upper end of the router bit and the end of the shaft would keep the end of the bit from vibrating. What do you think of that idea? Anybody had that problem before?

Forum Responses
(Cabinetmaking Forum)
From contributor C:
I got a used planer/molder and make all my crown moldings on that. I paid $400 for the machine and it was worth every penny. For a small shop I think it is great. As for supporting the router bit, good luck. Try shallower passes.

From contributor B:
I have the Grizzly planer/moulder. Definitely the way to go. I use it for crown, base, and frames for mitered doors. Well worth the money for the small shop.

From contributor J:
The over-the-bit support sounds dangerous to me, but some of the others may have a design that works great. I can't really visualize how you would mount it. Your router may not be square to the table top. I recently had a vibration problem on one of my tables and that's what it turned out to be. To check it, place a piece of 1/2" cold rolled steel in the collet and check it with a square that you know is square. Adapter plates are notorious for cocking the router in the table.

From contributor H:
Although there are some folks who would have you believe that you could build the space shuttle with a router and table…you can't. You really need a planer or shaper moulder to do what you are asking, safely. That vibration you are feeling and seeing will eventually lead to the bit breaking or the router bearings. The proper tool for the job always does it best, longest, and with less blood and aggravation.

From contributor E:
I agree with most of what was said above. Most shop built router tables are incredibly flexible in their ability to produce different types of work. However, most are not 400+lb. cast iron boxes with 3 hp induction motors. It is very difficult to eliminate vibration as you move into bigger bit sizes and at some point, the bits are just not safe. There are times when the Yankee in me tries to find less expensive ways to do things, but not at increased risk of injury. If you're a professional, it's time to step up to a shaper or moulder. If you're a hobbyist, you would do much better to find a moulding supplier in your area.

From contributor O:
Try multiple passes making shallow cuts.

From contributor S:
No piece of wood or any result is worth a drop of blood. You're crazy if you think you can stabilize a bit turning at 30K RPM with some jerry-rigged solution. No way would I put a crown bit in a router. I've got a 1 1/2" diameter ogee bit that will cut a 1" profile, and that thing is scary in a router, and it rotates without any wobble. I'm a non-pro and did my own kitchen from the studs out. $500 worth of cheap Ryobi equipment. $60 router. Did the 50' of 4" crown using two pieces of 2.5" solid oak and assembled them. Looks great. All light cuts with non-nasty bits. Never try to make low-end equipment do something it wasn't designed to do. Missing chunks of your body usually can't be replaced.