# Router Bit-Rabbet with 1/4" shank



## belaire445 (Oct 21, 2012)

It's been quite a while since I'm posted anything but now I'm hoping someone can direct me to where I can find a rabbeting bit with a bearing at the top, not at the bottom. Now when I refer to the top I mean when installed in the router the bearing would be closest to the router. I searched the Whiteside router catalog and could not find one. I need to make a 1/4" rabbet on the side of a cabinet I built. I can't rout from the inside. I'm making a large opening for glass on both sides of the cabinet to duplicate the glass doors.on the front side. thanks


----------



## DesertRatTom (Jul 3, 2012)

Could you use a mortising bit for that? Going to be hard to find a rabbeting bit with a quarter inch shank. A mortising bit will give you a flat bottom cut. Here's a pix. This has a half inch shank, but I found a Yonoko brand bit on Amazon that has the quarter inch shank. I use it for hinge mortising with my Colt. Works fine. Here is a link to a CMT mortising bit with a quarter inch shank and top mounted bearing. The pix is of a half inch shank with a profile to show the flat bottom. You can lay a straight edge on the door, clamp it and use it to guide this bit.


I found a


----------



## DesertRatTom (Jul 3, 2012)

Here's the link to the CMT bit. Couldn't edit the previous post. 



https://www.amazon.com/CMT-801-128-11B-Mortising-2-Inch-Diameter/dp/B001FD7K86/ref=sr_1_35?dchild=1&keywords=Mortising+bit&qid=1613113891&sr=8-35


----------



## papasombre (Sep 22, 2011)

Hi, Blaire445.
It is not difficult to buy that bit. In fact, I bought mines for 1/8" and 1/4" rabbets a long time ago.
Rockler has a rabbeting bit set that can be used with several bearings to get any rabbet size.








Rockler 1/4" Shank Rabbeting Bit Set


Includes a set of four bearings to achieve the following cutting depths: 5/16", 3/8", 7/16" and 1/2". Unconditional guarantee.




www.rockler.com


----------



## DesertRatTom (Jul 3, 2012)

papasombre said:


> Hi, Blaire445.
> It is not difficult to buy that bit. In fact, I bought mines for 1/8" and 1/4" rabbets a long time ago.
> Rockler has a rabbeting bit set that can be used with several bearings to get any rabbet size.
> 
> ...


That's a nice bit, however, as I read his post, Belaire is working on an already assembled door frame, so the large diameter will not get into the corners very well. The smaller bit will cut closer to the corner, so he will have less hand work to do to square up the rabbet into the corners. That was my thinking anyhow.


----------



## belaire445 (Oct 21, 2012)

DesertRatTom said:


> That's a nice bit, however, as I read his post, Belaire is working on an already assembled door frame, so the large diameter will not get into the corners very well. The smaller bit will cut closer to the corner, so he will have less hand work to do to square up the rabbet into the corners. That was my thinking anyhow.


The router bit that I am looking for, as noted in my post, needs to be a 1/4" shank but the bearing needs to be on the "other" side of the carbide cutter. I have numerous rabbeting bits but the bearing is on the 'wrong" side of the cutter. I need one that has the bearing on the router side of the cutter. I hope this makes sense.


----------



## Bob Bengal (Jul 24, 2020)

So the router will be on the outside of the already built cabinet and you want the rabbet to be on the inside?

I don't know, but will throw a couple of ideas out there. Maybe a slotting bit, with a bearing that can be placed above or below the cutter, you can get a bearing with a different O.D. to change the depth of cut.

An example

Or instead of a bearing use a bush guide.


----------



## DesertRatTom (Jul 3, 2012)

belaire445 said:


> The router bit that I am looking for, as noted in my post, needs to be a 1/4" shank but the bearing needs to be on the "other" side of the carbide cutter. I have numerous rabbeting bits but the bearing is on the 'wrong" side of the cutter. I need one that has the bearing on the router side of the cutter. I hope this makes sense.


Yes, that is a top mounted bit. Am I correct in assuming the doors are already assembled as in the picture? If it isn't assembled already a rabbeting bit isn't necessarily what you want, and I don't think I've ever seen a rabbeting bit with a bottom mounted bearing. If it isn't assembled, you can simply use a straight bit and run the piece against the fence and you don't need the bearing, depending on the profie of the piece. For either a bearing or a fence to cut a rabbet, the profile must be flat to a height slightly higher than the rabbet so there is something for the bearing to run against.

That's why I mentioned attaching a straight edge for a mortising bit's top mounted bearing to index against. 

Is the door already assembled or still in parts? I suggest you take a bit of scrap material you used for the rails and stiles, and on the end, mark out what you want to cut out. If there is straght material left above the rabbit, then you have a lot of options. But I still would not use a rabbeting bit if it's assembled already.


----------



## Biagio (Mar 2, 2013)

Hi Belaire, it sounds like you intend to cut out the opening on each side, then you want to undercut the openings on the inside, in order to fit the glass from the inside? If so, you will be using the cut edges of the openings for guides, as there will be no place for a straightedge.
There is nothing to stop you from using a rabbeting bit, as you suggest, with a bearing and collar on the shaft. The collar has a grub screw to hold the bearing in place. You could remove the lower bearing for this purpose, or simply leave it on. The bearing and collar would be in position like in the bit shown by Tom above. The image is from Amazon.


----------



## CharleyL (Feb 28, 2009)

WOW, is this ever going to be a tough job to get right on a cabinet that has already been built. It might be easier to just start over and make another cabinet of similar design.. If cut as proposed, the grain above and below the new opening is going to be running in the wrong direction for strength. With such a small amount of it left after the cut out, it may fail sometime later too. I can fix a lot of problems during my project builds, but I develop considerable "sweat and tension" when I have to go back and make significant changes after the finish has been applied. The chances of disaster are just too high.

Charley


----------



## Chris Itin (Oct 15, 2019)

I assume that you intend to cut out a portion of the sides and then install a glass insert from inside the cabinet to look similar to the doors.
Maybe it would be easier to make panels just like the doors and install them in cutouts you make in the sides. They would be raised from the carcass, but installed permanently, not on hinges.


----------



## Tagwatts (Apr 11, 2012)

You can purchase exactly the bit you want from Amazon. There are several sizes of bearings that come with a set in both 1/4 inch and 1/2 inch. There are enough variety and brands to choose what it may be that you need.


----------

