Hardware Store (HS) Extruder

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This is a variation on the extruder design (sans heater at the moment) that can be made from elements found at a common hardware store. Total cost for the extruder without the drive motor or any electronics is approximately $20. The great benefit of this extruder is that it can be made without exotic materials and with a minimum of tools; namely a drill press, a hack saw, a couple drills, and a #10-32 tap.

Here are the basic steps to construct this extruder:

  1. Fabricate the tension bearing bracket
  2. Fabricate the frame
  3. Strap the drive bearings to the frame
  4. Attach the drive screw
  5. Assemble the tension bearing bracket
  6. Attach the tension bearing bracket

Of course, calibration follows each of these steps and the build as a whole so this simplistic view of the construction maybe isn't correct enough to give you an exact idea of the time required. From personal experience, I find that it takes me about 4 hours to construct and assemble one of these extruders.

Let's get too it!


Bill of Materials

# Item Dimensions
1 Steal Bar Stock 1/8" x 1/2" x 8"
2 U-Bolt 1-1/4" x 1"
3 Skate Bearings 608
1 Vynil Aquarium Hose 1"
2 Angle Bracket 2" x 2"
1 Bolt 1/4-20 x 1/2"
1 Nut 1/4-20
1 Shoulder Bolt M6 x 5

Tension Bearing Bracket

The tension bearing bracket is a small L-bracket that bolts onto the extruder frame to hold a bearing and guide slightly less than a filament width away from the drive screw. The filament feeds down the guide and gets pressed to the drive screw by the bearing. The tolerances on this piece of the extruder are the most critical. The more time you take here, the better your extruder will work though you can get a very rough model to work wit a little extra effort.

The bracket is made up of several parts:

  • Two 2" L-bracket
  • One 608 Skate Bearing
  • One M6 Shoulder bolt (or equivalent)
  • A few Flat washers

The steps below show these simple steps:

  1. Bend the 2" L-bracket into shape.
  2. Drill holes in L-bracket for shoulder bolt.
  3. Drill two holes in other L-bracket for guids.
  4. Cut two guide flanges off.
  5. Bend guide flanges to shape.
  6. File or grind guide flanges to final shape.
  7. Assemble tension bearing bracket.


<More to come!>