Build

Sheet metal brake

By telleropnul, May 19, 2023

Also called a pan brake or sheet metal folder.  Not to be confused with sheet metal guillotine shear.  A sheet metal brake is for bending sheet metal.

Part names:

  • Bending leaf
  • Bending leaf handles (2x preferred)
  • Stationary Bed
  • Clamping bar (acute angle wedge shape with sharp corner, horizontally adjustable to perfectly align with bending inner radius to support different thickness sheet metal to bend)
  • A clamping bar with individual fingers is helpful when you need gaps, for example, when folding two sides of a box corner.

Key design elements:

  • Bending leaf and stationary bed need to have a near perfect sharp corner.
  • Clamp needs to be wedge shaped to allow for over-bending sheet metal past 90 degrees.
  • Hinge pin center line = pivot.
  • Hinge plates will always have a surface that is perfectly aligned with center line.
  • Flip 1 hinge plate to get range of motion needed for bending.
  • To position the hinge horizontally, notches will need to be cut out in the bending leaf and stationary bed.
  • Mount one hinge plate on top of the bending leaf using bolts.
  • Mount the other hinge plate recessed into the stationary bed (or use a piece of timber and mount both the stationary bed and hinge plate side-by-side for the same effect, if of the same thickness).
  • Steel angle needs to have a sharp corner.

Note to self: buy a used second-hand professional metal brake rather than make something that does not work as well.

Thought of getting a pair of these.  Won’t work a second pair won’t be able to hold the work piece as you can only insert about 20mm.

 

Don’t buy this – weak clamp:

FP30 $239 AUD
Has individual fingers.  Limited to 300mm.  Uses a die set, so better suited for thin material only.  Might be better to use a die set on a hydraulic press at some point.

Vice mount sheet metal bender $70 AUD
Has individual fingers and open ends (no hinge).  Limited to 125mm.  Die set. Bench vice may obstruct material being inserted; I have room to insert 60mm of material in my vice.  This will work for now.

Got this Kinchrome one ($75 AUD): https://www.supercheapauto.com.au/p/kincrome-kincrome-vice-metal-bending-brake/593989.html
Surprisingly good quality.  Heavy.  Magnets clip on well.