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Hard turning, finishing the part.
- Thread starter P. Waller
- Start date
The facing went as as well as expected, the face grooving not so well. This 25" X 100" lathe will not power feed slow enough for this tool so it must be done by hand. It is difficult to keep the tool loaded enough that it will not chatter at the bottom.
Are you referring to the rust coloured stain on the ways?
If you would elaborate on this I would appreciate it. Seems like the last thing I would expect to happen.
This is a joke, several weeks ago someone posted a thread on this forum about waylube staining their machine ways, I advised him that the best way to avoid this is to have 2 machines.
One to use and one to admire, I got mail for that comment.
To answer your question lubrication products and use will discolor the metal surfaces over time, this is inevetable, the machine pictured above is nearly 20 years old and has been in a working job shop since new, rode hard and put away wet so to speak.
Also the facing operations went well, the face grooving took forever.
Faced the second part today, reasonable finish with just a wee bit of chatter marks between the jaws as so often happens.
40 RPMs(260 FPM) at the OD, .050" DOC, .008" Feed rate using a CNMT insert for roughing.
Used a TPG 431 insert for finishing at 28 RPMs, .015" DOC and .006" feed for finishing.
.006" Feed Per Minute X 28 RPMs is .168" per minute X 6" length of cut = 1 hour of spindle time for the finish pass alone.
This sort of thing will drive a hobbyist chasing tenths absolutely bonkers, you will never get a 25" part that has had its OD milled by circular interpolation to have 0 run out. The mill used for this part did an excellent job of it however considering that it was done in halfs, a 24" travel Y axis machine will not mill a 25" circle (-:
Back in the day, we cut similar parts for the oilfield.
Supported the part with bolts and t-nuts.
Parts had to be flat within .005”
Looked somewhat like what you have there.
Toughest part was the sealing faces, full radius about .500”
Think that your part had a thicker ring around the OD.
Usually started out as torch/plasma cut plate, it was a bear to get through.
Supported the part with bolts and t-nuts.
Parts had to be flat within .005”
Looked somewhat like what you have there.
Toughest part was the sealing faces, full radius about .500”
Think that your part had a thicker ring around the OD.
Usually started out as torch/plasma cut plate, it was a bear to get through.