Chamfer help

The face of the chamfer.

The right angles.

UA100

Not unless established woodworking convention is opposite from engineering and metalworking (machining). A 1/2" x 45 deg chamfer would have two short legs of 1/2 inch each and a face width (hypotenuse) of (1.414)x(1/2)= .707 inch.

David Merrill

A "chamfer" is often refered to as a "bevel" in woodworking, "bevel" being one of the accepted definitions of "chamfer".

In woodworking, if a client asks you for a 1/2" 45 degree chamfer on a table leg, you'd best measure the face. Put a 1/2" 45 degree chamfer on a 3" X 3" table leg with your engineering formula and you would not have a leg left to stand on.

Using a CAD program, AutoCAD in particular, the chamfer command requires 2 distances, the resulting chamfer is not a part of the formula.

I agree with Swingman, the face of the chamfer measures to be 1/2". I did my 1st one in class tonight, it will translate to a blade depth* of 3/8" from the router's face plate/ \table to the top of the blade. Then you get your 1/2" - 45º bevel face, just to be "straightforward" about it.

Alex

Not really true. A chamfer is always 45 degrees. A bevel varies.

While all chamfers may be a bevel, not all bevels are chamfers.

First, saying "45 degree" chamfer is redundant (see above).

A 1/2" chamfer on a 3" face would leave 2" of "flat".

It's been that way since Grandpa taught it to me and I'm fairly certain he didn't make it up.

UA100

Since there appears to be some debate, even amongst engineers and woodworkers, it would appear that if a client (who may have their own, possibly different assumptions) asked for a 1/2" 45 degree chamfer, you'd better ask them EXPLICITLY what they mean (with diagrams where neccessary).

BugBear

Which is usually is. Woodworking chamfers are the face measurement, because they're cut by hand in repeated passes, and you stop when you've made the face to the right size. If we had more milling machines and fewer spokeshaves, we'd probably do it the other way.

Not really true. Check any dictionary/encyclopedia for a definition of "chamfer".

See above

And I learned it the other way ... from a different Grandpa, who I'm fairly certain didn't make it up either. Not to mention that working in wood with architects, it's been a face measurement more often than not ... not that I would use the breed as a definitive reference on most anything to do with woodworking.

Nonetheless, next time an someone specs a chamfered edge on a rail, you'd do well to get a clarification.

And even that may not be your salvation, particularly if that "client" is an architect, or female, or both. I see a radius spec'ed quite frequently on trim details and almost always prepare for a battle when said radius is seen for the first time, in context, in its surroundings, and precisely as drawn.

That's where the phrase "executed per plan" becomes the final word on the subject, the pouting bottom lip notwithstanding.

Precisely. If you're lucky, the trim detail sheet will usually show the desired results.

If I were making a "1/2 inch chamfer" by hand, I would start by drawing a line 1/2" in from the edge of the board on the two adjacent sides. I would then cut away with the spokeshave until I reached both lines. As long as the surface was flat, that would give me a 45 degree chamfer. Thus my answer to the OP is that the 1/2" is the measurement of the legs of the triangle that intersect at 90 degrees. Note that is only MY answer, I in no way assume that it is THE correct answer.

Dave Hall

If I marked out before making a chamfer (even a lambs tongue) other timber framers would laugh at me !

Chamfers belong to that great tradition of hand work. I know people who even frown at the use of a shave to cut them, rather than a bare drawknife. Look at Gimson or Barnsley work - those stopped chamfers right into the corners of frames, all perfectly placed, and with the edges of the taper pointing exactly into the stop of the facing chamfer. You can't get accuracy like that by marking it and trying to cut to a line, it has to flow spontaneously from the tool.

Oh, the Zen of chamfering. I guess I am just an unwashed hobbyist - the "force" just isn't with me yet.

Dave Hall

BUWAAHAHAHAHAAAAaaaaaa! Exactly.

Alex