OK, the back story. I am a complete nubie, but usually quite handy with other tools in other areas. On the Logan lathe I recently got home and am starting to set up, I noticed that the set screw holding the cross feed graduated collar was not going to come loose easily. This lathe has been sitting for more 30 years, unused, but in very good shape considering. I did the normal things, days of soaking in different loosening agents, heat and cool cycles making sure not to get it too hot, mild taping to try to break bond. Nothing was working. I also though that it must be a very short set screw since it was so deep in the collar. ( this part is a hint )
Fast forward to me getting impatient and starting to drill out the set screw with left hand drill bits, occasionally measuring depth so I would not go to far. Drilled and then tried to get collar to move, nothing. Drilled deeper, nothing. Now, I am below the level of the shaft but still cant get it to move. Went deeper still and then it finally started to move and I got the collar off. I completely drilled through the shaft and slightly into the other side of the collar.
Now for the mystery. In examining the shaft, I noticed that part of the "hole" I had drilled had threads in it. My father in law was a master machinist and was second generation in owing a full machine shop. To say that he was skilled is an understatement. This was a small hobby lathe that he had in his retirement. It is my assumption that he drilled out then tapped a deeper hole into the shaft and collar to "Lock" the collar in place. Can any of you tell me why he might have done this? If he did it, he did it for a reason,. I just am puzzled.
Now for your suggestions. I have a hole in a shaft that is not small, but the shaft is not needing too much strength. What are your suggestions, again knowing my very new skill levels? I could re-drill shaft hole and fill with plug or threads and then machine to original measurement, or should I use something like devcon or jb weld and fill the area and machine that down. Open to other thoughts too.
As mentioned in an early thread, I have quite a bit of backlash and at some point it will be likely that I have to replace this shaft anyway but following many of your suggestions, I was hoping to get a few chips under my belt first before spending the money to buy new parts.
Thanks for your thoughts.
Fast forward to me getting impatient and starting to drill out the set screw with left hand drill bits, occasionally measuring depth so I would not go to far. Drilled and then tried to get collar to move, nothing. Drilled deeper, nothing. Now, I am below the level of the shaft but still cant get it to move. Went deeper still and then it finally started to move and I got the collar off. I completely drilled through the shaft and slightly into the other side of the collar.
Now for the mystery. In examining the shaft, I noticed that part of the "hole" I had drilled had threads in it. My father in law was a master machinist and was second generation in owing a full machine shop. To say that he was skilled is an understatement. This was a small hobby lathe that he had in his retirement. It is my assumption that he drilled out then tapped a deeper hole into the shaft and collar to "Lock" the collar in place. Can any of you tell me why he might have done this? If he did it, he did it for a reason,. I just am puzzled.
Now for your suggestions. I have a hole in a shaft that is not small, but the shaft is not needing too much strength. What are your suggestions, again knowing my very new skill levels? I could re-drill shaft hole and fill with plug or threads and then machine to original measurement, or should I use something like devcon or jb weld and fill the area and machine that down. Open to other thoughts too.
As mentioned in an early thread, I have quite a bit of backlash and at some point it will be likely that I have to replace this shaft anyway but following many of your suggestions, I was hoping to get a few chips under my belt first before spending the money to buy new parts.
Thanks for your thoughts.