Bone screw machining

Machining challenge is to avoid burr formation in milled features in the tip when doing the thread whirling operation.

Benefits

• Good surface finish
• Secure process
  

Machining solution

1. Turning of tip
2. Milling of grooves
3. Thread whirling of tip (for more information, see below)
4. Deburring pass with mill
5. Thread whirling complete

Machining solution – thread whirling of tip

Selected component features

• Machining tip
• Machining thread
• Machining head

Machining the long and slender thread is preferably made by thread whirling to avoid bending and vibrations.

Thread quality is a challenge when high feeds are used in the thread whirling. Facets is a common problem.

If the thread diameter is changed, the setting angle of the whirling ring has to be changed too. Use the calculator for correct programming.

Every whirling spindle has a gear box reduction, due to size restrictions of the unit. Remember to take this into consideration. The programmed rpm will not the actual output. In our case the reduction was 50 %.

Benefits

• Good surface finish
• Good dimensional accuracy
• Secure process
• Productive
  

Machining solution (example)

Machining solution – thread whirling

The cutting data as below will give a good cutting process with acceptable

sound levels. It is possible to surpass these values, but the sound level will

increase rapidly and facets are formed.

Machining solution – Head

1. Turning front of head
2. Roughing back of head
3. Finishing back of head
4. Parting off
   

Benefits

• Chip control
• Secure process