Linear Bearing for Router Table

[PaulH]

I built a router table (non CNC, like this one) for constructing cabinet doors and the like. Presently I clamp the fence down to the table top with a couple of C-clamps. This works reasonably well, but can be difficult to square up with the T-track that my miter gauge rides in.

As I see it, I have two choices:

First, I could set this up like the fence on a table saw. Look at a Delta Biesemeyer or Jet XACTA fence to get a better idea of this. Basically it's a slot with a T-square. The top of the T sits in the slot and the vertical leg of the T is the fence. There is some kind of cam that locks it into position. Pros: quick and easy to set up. Cons: fence doesn't always stay square when the lock is released.

Second, I could take a page from the CNC Router book and put a rail on both ends of the table and have the fence ride on the rails. Then it would always be square to the table and the rails, within the limits of whatever slop the setup has. Pros: Always square even if it's unlocked; easy to set up. Cons: A lot more complex; How would I lock it down?

I'm soliciting input here, so feel free to brainstorm, even if you think your idea sounds a little crazy!

[anoel]

I don't really see a point in it... there's no real reason to use both the fence and the miter slot at the same time. When you use the fence you typically use a push block and/or feather boards. And when you use the miter slot you typically back the fence off or remove it so the offcut of the work piece clears it.

[ger21]

I use an Incra Jig Ultra http://www.woodpeck.com/ultra.html for my router fence. I built my own fence, didn't buy theirs. Locks down in 1/32 increments, with .001 adjustability. Super quick and easy to change positions. I owned their previous version before this one. Although a little tedious, it's also possible to cut dovetails with it because of the repeatability. I've made a batch of 10 dovetailed drawers pretty quickly with it.

[ger21]

Originally Posted by anoel I don't really see a point in it... there's no real reason to use both the fence and the miter slot at the same time. When you use the fence you typically use a push block and/or feather boards. And when you use the miter slot you typically back the fence off or remove it so the offcut of the work piece clears it.

For profiling the ends of narrow stock, it can be much faster to use the fence as a "stop" while using the miter gauge.

[mxtras]

I think he is refering to the adjustment on the fence - where the said slot is perpendicular to the fence....I think. I see the merit in his endevour.

Another option might be to use racks in the slots and then a common axle for two pinions to act against the racks. By turning the pinions, it would move both sides equally and maintain parallelism. The rack could be the guiding, perhaps. Locking could be accomplished with either an expanding wedge arrangement of some sort inside the slots (built onto the racks) or a compression collar on the axle - like a motorcycle triple clamp gripping a fork tube.

Just an idea.

Gotta run - sorry to be so brief! Gotta catch a plane!

Scott

Scott

[spalm]

One thing to keep in mind is that the fence needs to be easily removable. A lot of operations use the bearings on the bits for alignment.

For years I used a T-square that I made, this would align it self with the T-slots. I locked it in place with two small bar clamps. The fence on a router table needs to be firmly locked as their can be quite a kick back some times.

Steve

[PaulH]

As I have found while using the router table, the fence doesn't necessarily have to be removeable; usually it can be pushed all the way to the back of the table and have the same result.

I found two sites with plans for router tables fences that caught my eye for one reason or another:

http://www.woodsmithstore.com/wfenceclose.html -- This is the classic fence. It clamps to the table, but there is no alignment mechanism. To set it up quickly you would have to align it to the bearing on the bit. To align it to the miter slot would be no different than what I do now.

http://www.patwarner.com/routerfence.html -- Very interesting concept, but seems to be overkill. This uses dados in the wood and flat pieces of metal as the guides. For course adjustment the whole assembly moves. For fine adjustment, only the top part move. This is actually quite similar to the Incra fence that Gerry linked to.

I'm thinking of putting two rails, probably drill rod or something similar, under the table. I could easily make some bushings out of delrin or something similar to ride on the rails. If the rails are mounted in adjustable bearing blocks like the X-axis of a gantry-style CnC router, I would be able to adjust one to be perpendicular to the miter track and the other to be parallel to the first.

To hold the fence in place, I'm thinking turn the entire fence into a big clamp. Have a jaw at each end and a piece of threaded rod that runs through the length of the fence. All I would have to do is tighten a handle down that draws the jaws against the edge of the table to hold it in place.

Thoughts?

[Jan]

Check your local TV listings or google for "the router workshop".
This is a show about using the router with a table and all the things these two make.
The old man is the star of the program and does not have any t-track installed in the table, matter of fact the fence is never "square to the cutting bit", reason being is this is a rotating bit, not a table saw type machine.
No need to bring table saw thinking to the router table, there apples and oranges

[ger21]

Originally Posted by Jan Check your local TV listings or google for "the router workshop". This is a show about using the router with a table and all the things these two make. The old man is the star of the program and does not have any t-track installed in the table, matter of fact the fence is never "square to the cutting bit", reason being is this is a rotating bit, not a table saw type machine. No need to bring table saw thinking to the router table, there apples and oranges

If using a miter slot to feed your stock, to make box joints or dovetails, for example, the fence MUST be parallel to the slot. Sure, you can just use the fence, but the miter slot gives you some added stability for certain operations.

[anoel]

Fence for boxjoints and dovetails??? Never... only the miter slot and jig, why on earth would you use the fence? For sliding dovetails only the fence is used and not the miter...

I cut box and dovetails all the time for my guitar amp cabinets. Using the miter and the fence together is like cutting to stock to length on a table saw using the fence as a stop... Big recipe for a bind and a kick back and a potential injury. It's just not something that you do.

The only thing that really matters with a router table is that the fence face be 90 degrees from the table face and the distance of the fence face to the Router bit.

I've watched the Router Workshop guy many times and have seen many shops using router tables for custom cabinets and furniture. (In fact one of my drinking buddies runs a successful custom woodworking shop. Never seen him use the two together.)

[ger21]

When routing dovetails with the board standing on end with a miter gauge only, how do you position the stock? With box joints, you use a jig to hold the position.

[anoel]

Well, I use a dedicated Halfblind Dovetail jig. Never tried anything but sliding dovetails on a router table.

But Even for Through dovetails I can see how you could route the tails but how are you going to do the pins on the table? I've been racking my brain trying to figure out how but can't come up with anything.