- Joined
- Sep 20, 2021
- Messages
- 152
Think you're right... I thought these levers did the same thing....Sounds like your problem. The gear sets engaged for power feed and the half nut are different.
Think you're right... I thought these levers did the same thing....Sounds like your problem. The gear sets engaged for power feed and the half nut are different.
No, the one youre using is a mechanical geartrain inside the apron that is for removing material from the diameter of the part.Think you're right... I thought these levers did the same thing....
That should be that, then! Next pic, smiling with 18 tpi threads!Think you're right... I thought these levers did the same thing....
You know what they say here, pictures, or it didn't happen! Show us your threads!Yippie - yes, 18tpi on the money! Thx all
Using the wrong feed lever really makes sense.Based on the chart, the 80t and 127t gears are simply acting as idlers. The ratio of the a and b gears, along with the QC gear box gears determine the thread pitch. In the configuration shown, the input shaft to the gear box should be turning at the same RPM as the spindle.
I see two possible explanations for your result. First, the half nuts may be engaged at the wrong position on subsequent passes, giving the effect of a multi-start thread. Second, lathes that I have seen using your setup have an alternative method of using power feed; namely, there is a key slot in the lead screw which drive the power feed to produce a finer lead than would be obtained with the typical method using the half nuts. Assuming that you are cutting decent threads but the wrong pitch, it would suggest the latter.
It takes a village!Thanks, fellas!
Those threads look quite nice !But of course..