$5 RAIL BENDER

I’ve seen a number of expensive rail benders and they seem fairly easy to make, except for the roller. I’ve designed, made and used a bender that is cheap, easy to use and relatively easy to make. Some lathe work is required, but great skill is not needed.

From 1/8" steel, cut two 5" X 5" pieces. Bend one piece in half to form a 90 degree "L".

Cut slot in the bent piece (5/8" x 2 5/8") for adjuster and movable roller guide (5/8" x 3/8"). Drill holes ( 3/8") for fixed rollers which also hold the pieces together.

MAKE 3 ROLLERS 1 ¼ X 1 3/8"dia. OUT OF A HARD PLASTIC (PVC). DRILL A HOLE IN THEM TO ALLOW FREE TURNING OF THE BRASS SPACERS (3/8 X 2 ¼").

THE ADJUSTABLE ROLLER BOLT IS SOLDERED TO THE ADJUSTER. IT HAS A HAND CRANK WHICH IS ATTACHED WITH 2 SCREWS. IT IS HELD ON THE SHAFT (BOLT) WITH A SMALL WASHER AND WING NUT ON TOP. THE OTHER TWO ROLLERS USE A 3/8" BOLT, 2 LARGE, ONE SMALL WASHER AND A NUT.

MAKE THE THREE BRASS ROLLER SPACERS FIRST. THE LENGTH IS DETERMINED BY THE LENGTH OF THE BOLTS USED. CUT THE ROLLER STOCK (1 ½"PVC ROD MATERIAL) ½ INCH LONGER THAN FINISHED LENGTH. DRILL THE ROLLERS TO TURN OVER THE BRASS ROLLER SPACERS. MOUNT THE ROLLER ON THE SPACER BETWEEN THE LATHE CENTERS. A SCREW IN THE ROLLERS END WILL KEEP IT TURNING ON THE FACE PLATE. TURN THE OUTSIDE ON ALL THREE ROLLERS TO A SMOOTH CONCENTRIC SURFACE. TURN THE GROOVES WITH THE SPECIAL LATHE TOOL. THE LATHE TOOL IS MADE FROM A PIECE OF THE RAIL TO BE BENT SOLDERED TO A PIECE OF BRASS (SEE ABOVE). SHARPEN THE RAILS EDGE TO FORM A CUTTING EDGE. TWO TOOLS CAN BE USED TO CUT SEPARATE GROOVES IF MORE THAN ONE SIZE RAIL IS TO BE BENT. MAKE SURE ALL GROOVES ARE THE SAME HEIGHT FROM THE BASE.

AFTER GROOVING ALL THREE ROLLERS, CUT THEM TO LENGTH SO ALL GROOVES ARE AT THE SAME HEIGHT.

SOLDER THE ADJUSTABLE ROLLER BOLT TO THE ADJUSTER THE ADJUSTER FITS INTO THE SLOT IN THE BENT 5 X 5 PIECE. THE ADJUSTABLE ROLLER BOLT GOES THROUGH SMALL SLOT IN FLAT 5 X 5 PIECE. ADJUSTMENTS IN THE DEGREE OF RAIL BEND ARE MADE BY TURNING A WING NUT WHICH IS SOLDERED TO A HEADLESS BOLT. THIS BOLT GOES THROUGH THE ADJUSTER AND INTO A NUT SOLDERED TO THE BACK SIDE OF THE ADJUSTER. SOLDER THE "L" SHAPED ADJUSTER STOPPER IN PLACE.
MAKE A HANDLE TO OPERATE THE MOVABLE ROLLER. IT NEEDS TO BE THIN AND CURVED TO CLEAR THE MOVABLE ROLLER'S SMALL FLAT WASHER AND WING NUT.

OPERATION

MOUNT THE BENDER IN A STABLE VICE, BY THE LOWER FLANGE OF THE BENT PLATE.
LOOSEN THE ADJUSTABLE ROLLER WING NUT AND MOVE THE ROLLER AWAY FROM THE OTHER ROLLERS UNTIL THE RAIL FITS EASILY IN THE GROOVES OF ALL 3 ROLLERS. TIGHTEN THE ADJUSTER WING BOLT TO MOVE THE MOVABLE ROLLER TOWARD THE FIXED ROLLERS. TIGHTEN THE ADJUSTABLE ROLLER'S WING NUT TO REDUCE THE STRAIN ON THE ADJUSTERS. TURN THE CRANK WHILE HOLDING THE LONG END OF RAIL. IF YOU MAY NEED TO PUSH THE RAIL TO HELP THE CRANK, YOU ARE PROBABLY OVER WORKING THE BENDER. DO NOT TRY TO MAKE THE FULL BEND IN ONE PASS. REVERSING THE CRANK WITHOUT CHANGING THE SETTINGS WILL BEND THE RAIL MORE ON EACH PASS. I SUGGEST DRAWING ARCS ON A PIECE OF PLYWOOD OR PAPER FOR EACH CURVE NEEDED AND TESTING THE RAIL TO THEM. CURVED RAILS CAN BE INSERTED "BACKWARDS" AND THE CURVE REDUCED UNTIL THE RAIL IS STRAIGHT, IF NEEDED.