Mittler Bros Machine & Tool 2800 72” Ultimate Box & Pan Brake - Manual (Page 8)

02-08-2013 Rev 4
OPERATION
Your brake is a general purpose tool for bending and forming sheet metal. The brake is operated in the
following manner. The clamp of the brake is opened by pushing the clamp handles toward the rear of the
brake. Insert the material to be bent into the opening between the clamp and table assembly and clamp
the material in place by pulling the clamp handles forward. Raise the apron to bend the material to the
desired angle.
Capacity
The capacity of the 48" Brake is 16 gauge mild steel or 20 gauge stainless steel.
The capacity of the 72" Brake is 18 gauge mild steel or 22 gauge stainless steel.
Box & Pan Bending
The fingers can be removed and repositioned on the clamp assembly by moving the clamp handles fully
to the rear and loosening the finger clamp screws. Reposition the fingers to assemble the desired width
and secure the fingers to the clamp by tightening the finger clamp screws. Be certain that the tops of the
fingers are flush and parallel with the milled edge on the clamp and that the finger clamps are parallel with
the bottom edge of the clamp. As a general rule, use the wider fingers first and fill in with the narrower
fingers. Small gaps between the fingers may be left with no adverse effect to the work piece.
Hemming
The brake may be used to form hems on the edge of the work-piece in lighter materials. A hem is formed
by making an acute (reverse) bend in the work-piece and then clamping the bend flange under the clamp
to press the flange closed (to 180 degrees). Often the hem will not fully close in the center of a long piece
due to the fact that the outer ends of the brake are more rigid than the center. This situation can be
improved by inserting a strip of material (of the same thickness as the work-piece) between the work-
piece and the clamp block slightly longer than the open portion of the hem. Re-clamp the clamp to close
the hem. A tinner’s mallet or hammer is also useful for closing hems. Use caution not to use excessive
force on the clamp handles to close the hem.
NOTE: Forming hems is a secondary operation for a hand brake. If you adjust the brake to close a hem in
the center of the work-piece the brake most likely will not bend straight.