I take a slightly different approach. Being mean, I buy only the length of ballscrew needed for thread :-) I face the ends (hold the bs in an purpose-made alloy split collet in the 3-jaw) with a carbide tipped tool. Didn't need to soften or grind anything. Then center, drill, bore, ream to take an adapter. I used 8mm reamer for a 15mm nominal BS. At bottom of reamed hole I have about 10 mm of 6 by 1mm thread. Adapter has 8 mm portion and 6 by 1mm thread used to draw adapter into bs. Final fix is with Loctite (tm). Just finished the x-axis for a Senior mill using this approach. I used 500mm of bs for a leadscrew with total length of over 850mm, including portion to couple to stepper motor. |