- Joined
- Apr 12, 2013
- Messages
- 562
My 60 degree gauge 'thread fish' has rounded bottoms in the vee notches. When I round/blunt my threading bit tips to match, my threads look bad and are too tight, so I end up cutting too deep (per 3 wire measurement vs. 'book' dimension) to get a nut on. I'm beginning to wonder if the no-name gauge should have a relief in the tip. With a sharp bit the tip catches the radiused bottom before I can get the edges against the notch to really check my angles.
In the picture below I'm trying to build a 1/2-28 mandrel. To get the thread protector on, I had to cut to the point the thread measures .011" undersize...for a 2 hour to build paperweight!
Should I relieve the tip of the vee notch in my thread fish, or is that radius the proper tip geometry and I have another problem with my threading?
![Threads_zps6dff7b3b.jpg Threads_zps6dff7b3b.jpg](https://www.hobby-machinist.com/data/attachments/139/139069-e967e6eabccedb0f9e3d40163ecc8f80.jpg)
![Threads_zps6dff7b3b.jpg Threads_zps6dff7b3b.jpg](https://www.hobby-machinist.com/data/attachments/139/139068-e967e6eabccedb0f9e3d40163ecc8f80.jpg)
In the picture below I'm trying to build a 1/2-28 mandrel. To get the thread protector on, I had to cut to the point the thread measures .011" undersize...for a 2 hour to build paperweight!
Should I relieve the tip of the vee notch in my thread fish, or is that radius the proper tip geometry and I have another problem with my threading?
![Threads_zps6dff7b3b.jpg Threads_zps6dff7b3b.jpg](https://www.hobby-machinist.com/data/attachments/139/139069-e967e6eabccedb0f9e3d40163ecc8f80.jpg)
![Threads_zps6dff7b3b.jpg Threads_zps6dff7b3b.jpg](https://www.hobby-machinist.com/data/attachments/139/139068-e967e6eabccedb0f9e3d40163ecc8f80.jpg)