Problems Cutting Full Bullnose

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Cutting a profile in pine stock on a router table. March 14, 2004

I'm looking for information on how to correctly cut a full bull nose profile on pine stock on a router table. I need to bull nose a 1x4 along the face and both sides. I purchased a router table because the set up time to do it with a straight edge just takes too long and it becomes difficult as the size of the stock is small.

The problem I am having is that the fence halves on the router table do not move independently. As I run the stock along the first fence half everything is fine. The wood makes contact with the bull nose bit but when it reaches the second half of the fence, the stock no longer is in contact with the fence. I understand that an amount of material was removed to create the full bull nose and the size of the gap is equal to the amount of material that was removed. This is not a problem as I can keep even pressure along the first fence half and keep the stock straight. The problem occurs when I reach the end of the stock and it is no longer supported by the first fence half. The end either falls too deep into the bit and gouges the wood or I try to push the edge that was just cut against the second half of the fence which shifts the stock in and creates an unevenness or wave in the cut.

I would try to just cut the stock long and cut off the ends on a table saw, but then I would still have the problem running the bull nose on the short sides. Any tips on how to cut a full bull nose profile on both sides of a small piece of stock?

Forum Responses
(Architectural Woodworking Forum)
Add a strip of wood to the exit fence to adjust for the amount removed. You can also run the material with the uncut edge at the fence and use a feather board to hold it down.

The above suggestion of a strip of wood on the outfeed fence is the best way to handle this. You can use double stick tape to attach it. Taper the lead-in edge of the add-on strip. This way there will be no butt end for the moulding to hit as it leads onto this outfeed strip.

Why can't the fence be adjusted so that the bit creates the bullnose profile without creating any offset?

From the original questioner:

The fence is a one-piece design that will only adjust for the depth of cut by moving forward or backward.

Sounds to me like the fence is not straight and true. Check it against a straight edge.

A straight fence will work if you remove zero amount of stock from the highest point of the profile. The problem of missed sections occurs when the wood-blank is not perfectly straight. Even a half of 1/64" leaves a noticeable snipe.

The idea of the stepped fence is the most productive way to get what you need. 1/32" "depth of cut" will work if your stock is reasonably straight and can be held to the fence by feather boards or a power-feeder.

The adjustable fence is nice, but a quick alternative is to add a wood face to the fence. Create the step by running the face on the jointer set @ 1/32", stop the cut where the cutter will be. Now cut the hole / space to clear the router bit to the leading (thinner) side of the step.

When you have a rougher blank, make the step deeper. This will also clean up stock with a sawn edge, saving time spent shooting stock through the jointer.

When you cross cut the ends you must have a backer block to keep it clean and a guide system to keep it safe. Remember to cut the ends first while the edge is still square, otherwise you will have to make two backer blocks - one in the negative of your router profile.