ClappedOutBport
Cast Iron
- Joined
- Mar 30, 2016
I am specifying a knurl for the first time at work. I've made a few on my own, mostly crappy but sometimes passable.
I inspected some of the old ones from before I got here. Some are ok, but others downright unacceptable. Double and triple tracked, barely a few thou deep. I could sandblast them for that much grip. I would like to ensure that doesn't happen again.
These are large (between 1.5" and 3.125") nuts that need a reasonable amount of grip, but won't tear the plastic gloves our workers are always wearing. The material is 316 SS.
My two questions are:
Unfortunately we will probably go with the same company that goofed on the last ones. Which is why I need to be a bit more anal than the last engineer who only specced: "Diamond Knurl". I'm a bit worried about driving up the price, but if that's what it takes for good parts, so be it.
GD&T and engineering noob here, so I appreciate any advice.
TIA,
COB
I inspected some of the old ones from before I got here. Some are ok, but others downright unacceptable. Double and triple tracked, barely a few thou deep. I could sandblast them for that much grip. I would like to ensure that doesn't happen again.
These are large (between 1.5" and 3.125") nuts that need a reasonable amount of grip, but won't tear the plastic gloves our workers are always wearing. The material is 316 SS.
My two questions are:
- What would you specify for a nice knurl in regards to finishing with a nice, grippable, but not sharp surface? I was thinking 96 or 128 DP and then finish by cutting the height down some to make some less sharp flats on the tops.
- How would you specify this? I was thinking:
Code:DIAMOND KNURL PER ANSI/ASME B94.4-1984, CLASS 1, XX DP FINISH TURN TO NOMINAL DIAMETER
- If I wanted to give machinists choice to cut knurling, how could I specify that as well?
Unfortunately we will probably go with the same company that goofed on the last ones. Which is why I need to be a bit more anal than the last engineer who only specced: "Diamond Knurl". I'm a bit worried about driving up the price, but if that's what it takes for good parts, so be it.
GD&T and engineering noob here, so I appreciate any advice.
TIA,
COB