Sometimes, a board to be slotted is slightly longer than the maximum allowed by the carriage.  It is still possible to slot these, and the example below illustrates the temporary modifications to the machine and outlines the technique.  In this case, board slotting was used on a small edition of 12 books.  The large (46 x 31 cm) medium density fiberboard covers were covered with burl veneer, and the artist, Accra Shepp, and I decided that slotting would be an ideal method of firmly attaching the laminated paper/ linen spine to to heavy boards, while keeping their clean, unobstructed visual appeal.  More information about the book including images is available at my blog.


First the clamping bar is removed and a four cm. thick plywood spacer is added so that the boards will clear the edge of the carriage.  In this case, 2 clamps proved adequate to keep the MDF from shifting during the slotting process.  For typical binders board, it may be necessary to clamp it between plywood during the slotting.



As the slotting progress, the clamps are moved so they do not hit the blade guards.  As long as only one clamp was moved at a time, the position of the board did not shift.  The MDF was very easy to slot.



Once the left side of the carriage cleared the motor, the board was clamped on the on left side.  It is necessary to turn the machine on and off a number of times to adjust the clamps– it would be dangerous to leave the blade spinning when adjusting the clamps.



When the machine reached the end of the available space, the carriage was brought back to the center of the machine.  If you look at the position of the board relative to the plywood spacers you will notice that the board has been shifted about 5 cm to the left, then reclamped.    In this case, it was necessary to release both clamps, and slide the board to the left so that the right side of it could be slotted.  Depending on how exactly the board is repositioned at the front of the machine, it may be necessary to readjust the height of the blade to reenter the exact position of the previous cut.



Once again, the clamps are moved and pictured here the board is finished being completely slotted.  If a number of oversize boards were to be slotted, it might be prudent to glue the stacked plywood together, so that they don’t shift, or even attach them to the base in the pre threaded 1/4″/ 20 tpi holes for the original clamping bar.  The book board itself could be clamped in a simple press (two pieces of plywood with 4 carriage bolts at the corners) to eliminate some of the shifting of the various components that I encountered.  This would make the repositioning of the board much easier and more accurate.