Thanks, I have watched just about every video there is on the subject. I'm sure I can do it. Getting the right sized balls (and the right number) is my main concern. How are they measured?
Thanks, I have watched just about every video there is on the subject. I'm sure I can do it. Getting the right sized balls (and the right number) is my main concern. How are they measured?
A micrometer is the best way, but when measuring old ones, do it a few times around the ball turning the ball slightly each time.
They can get football shaped.
Lee
I'm getting .0925 - .093 I'll probably need to convert that to mm?
Tim
Tormach 1100-3, Grizzly G0709 lathe, Clausing 8520 mill, SolidWorks, HSMWorks.
Good point. I had ruled it out but from a different viewpoint. Thanks for the confirmation.
That is whay I suggested that he try it with a V bit or something. To rule that out. It would not have to be much deflection to get that kind of error on such a small engraving. The fact that some letters appear straighter may very well indicate a worn spot in the barrel of thee drag bit.
Lee
How are you holding your stock?
Step
I'd suggest as another test, engraving an uppercase T and L. The T will be single, along-axis strokes and the L will be a single along-axes stroke but with a 90-degree turn during the movement. That should isolate axis movement vs. flex/runout/backlash. Is it possible that you have accidentally turned on Formula Axis Correction in Mach3? If you have ever used it in the past, the equation you used will still be present.
Randy
I have never used it and I wouldn't know how to turn it on or off. We all bump keys at the wrong time so anything is possible. How would I check?
I'll try the T & L test but it will probably be tomorrow. I'm way behind in getting some computer generated samples worked up for customers.
I should restate that I have found that I have .007 - .008 backlash in my X axis.
After the adjusting the gibs and the thrust bearings I'm thinking it has to be down to the ballscrew. Even with less than 3000 hours on it. I had to replace the Z ballscrew at about 2000 hours. That was a little more obvious with little chrome bits in my way oil.
Spindle slop is also a possibility but I can't feel any.
Finding the right sized balls to replace the ones in the ballscrews is now my biggest problem.
That seems like a lot more than should be expected. A while back I traced a few thou of lost motion in the X-axis of my 1100 to a loose ball nut carrier on the X axis. The lost motion largely disappeared when the SHCS in the mounting block were tightened.
Attachment 307548
Here is another ball source, though I haven't ordered from them.
They can get you very close to 2.38 mm chrome steel balls. They also have .093" size. Those look like they are 10 cents each. Part number 37432.
Bal-tec
$20.00 minimum order.
Lee
I read about someone else having that problem and wished I had checked when I had all the guards and covers off.
I will check that out but I will have a replacement on hand before I tear it down that far again. Maybe I can fish a long extension in there and check them?