wrote:


and the carcasse. How square do things need to be and what sort of
fixes might I entertain if I determine that something isn't square
enough?


Basic premise: Cabinet "components" (generally speaking the casework,
the drawers and the doors) are all made up of individual "parts".

Perfectly square is the goal for all these components, and often "close
enough" will work if you can shim "components" into square during final
assembly of the cabinet. However, once you start shimming you're wasting
time that could better be spent doing something else, and there is NEVER
a guarantee of satisfactory results.

'Measuring diagonals' will tell you whether the four sides of a
"component" (drawer, door, drawer front, or the casework) are square to
each other; using an 'accurate square' of any kind will also tell you if
the corners are square (keep in mind that without proper preparation,
the stock between square corners could still be twisted, bent, warped,
or vary in thickness, and still cause problems).

The first step in solving your problem is to answer the questions:

Did you pay particular attention to the elements of "square" when you
built both your cabinet and drawers - IOW, ALL individual component
"parts" are indeed the specified project thickness, width, and length?

Did you use properly milled, straight, stock, of the equal thickness,
for each part?

Did you "batch cut" these parts before assembly? (more below)

Did you take steps during component assembly and glue-up to insure a
square results? (measuring diagonals, proper clamping techniques to
preclude warping by too much pressure, etc?)

The pursuit of "square" is the holy grail of cabinet making ... if you
did none of the above, you may well need to start over again as you can
spend hours attempting to shim the drawer slides and non-square
components, in all planes, and still not have a satisfactory end result.

One simple method/practice which will take you a long way to insuring
that your basic components (drawers, doors, casework) end up square is
to "batch cut" ALL "parts" of like dimension for these components.

"Batch cutting" parts is the practice of using the EXACT SAME machine
setup to cut ALL like project parts BEFORE changing machine settings
(move the table saw fence, move the planer table, etc).

AAMOF, this practice can't be stressed enough and will take you a long
way toward alleviating the problem you are currently experiencing.

Examples of this:

Cut ALL your "parts" (drawer sides, rails and stiles, casework sides,
etc.) of like WIDTH in the ENTIRE project, BEFORE you move your table
saw fence from that WIDTH setting.

Cut ALL your "parts" of like LENGTH in the ENTIRE project, BEFORE you
move your table saw fence from that LENGTH setting

Thickness, to project specs, ALL stock with the SAME final setting on
your planer, BEFORE you change that setting.

Etc, ad infinitum ...

This one simple practice (which does require some organization, planning
and thought) will insure that ALL project components parts, that have
identical dimensions, in thickness, width, and length, are indeed
identical and have not been subjected to errors introduced when moving
fences, machine tables/settings, etc..

(There are other things, like when using face frame cabinets, build your
face frames first, taking the time and necessary steps to insure they
are square, then assemble your cabinet sides on top of the already
"known square" face frames).

Paying particular attention to "square" with steps like the above when
building the three basic components of a "cabinet" (the casework, the
drawers and the doors) will save countless hours of trying to fit
non-square components during final assembly.

Multiply that by the number of cabinets in the average shop built
kitchen and the importance of pursuing the holy grail of "square"
becomes paramount.

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)