How to Build a Kossel Legacy 3D Printer

This page has instructions and hints to help you assemble your Kossel Legacy 3D printer.

Assembly:

Special Note...

Do not clean out every hole with a drill. Some holes are intended to capture the nuts without requiring a nut.

Captured Nut Beams

You may notice that it can be significantly easier with captured nut beams to put the nut on first and then slide everything on after it is already threaded. Alternately, we specifically try to use magnetic nuts so you can push them around in the beam with a magnet.

Carriage Stepper Motors

Motor - 4 m3 8 mm screw
Motor Spindle - 1 m3 Nut, 1 m3 8 mm screw

Spindle

Install 1 m3 nut with an 8 mm m3 screw.

Lower Bracket to Beam

Use 8 nuts to the extrusion using 6 mm screws.
Install m3 20 mm button heads screws through the corner pieces.

Top Bracket

Prepare, but do not attach to the extrusion, 6 m3 8 mm screws to the frame cheeks. Use 6 m3 20 mm socket head screws with nuts for the top corner pieces.

Idler

Install the 608ZZ Bearings into the 3 plastic idlers and connect the 3 m3 40 mm tensioner bolts with a lock nut to the top corner piece. Then put the idler and everything else into the open beam all at the same time.

Install the 3 limit switches on the frame cheeks with m2.5 12 mm socket head screws.

The Carriages

** Note, be especially careful not to drill out holes any more than necessary unless the screw needs a nut. The 6 bearings, for example, do not require a nut but instead are held in by the plastic.

Each bearing requires 1 m3 12 mm screw, 1 washer and 1 623zz bearing in that order.

The limit switch screw currently uses a 16 mm m3 screw. The string anchor uses an m12 m3 screw.

Center Head

The center head uses the same 20 mm m3 screws and up to 2 nuts, 2 washers and 2 jam nuts to adjust.

The Rod Ends

Prepare each rod end by wrapping it in string before drilling it with a 3.3 mm drill bit. Then tap it with a 4 mm coarse tap. Be especially careful to frequently reverse the tap.

Each carriage rod connector uses 20 mm m3 button cap head screws and up to 2 nuts, 1 jam nut and 1 washer. When you are all done, you will want the spacing between the rods to exactly match at the carriage and on the head. A small adjustment can be made when adjusting the carriage tightness around the beam by tightening the inside or outside screws, however, you may find that you need to play with nuts, washers, jam nuts, etc. to get them to match exactly.

The Extruder

You can hang a beam from the middle of one of the sides to hang the extruder. HB designed an Airtripper mounting bracket which you can download:

https://docs.google.com/file/d/0BwwU9Nx1dsISODVCb1V5X213SEU/edit

The bracket takes 2 8 mm and 2 12 mm m3 button cap screws with fender washers on the airtripper and a nyloc nut to be certain it does not vibrate loose.