I have a problem with a operation I am using my Sunstrand CNC lathe, with Fanuc controls, for. I am turning the ID of a can that houses a Hermetic Commercial motor. I put the motor/can assembly on the lathe using the ID bore of the motor. I am cutting the ID of the can that contains the motor. The size of the bore is 4" and my expanding segments expand to .04 bigger than the bore and is 4.75 inces long. The problem I am having is that it is impossible to create a perfectly straight bore. At the cut end of the can I am allowed to have a runout of .006. I get runout readings from .002 to .012. My lathe arbor measures .0008 runout. The ID of the can being cut is 7.8" and we cut .0135 off for an area of 1" depth. The can is 14" long and the area being cut is around 6" past the end of the end of the arbor. Is the runout problem caused by the .0008 runout in my arbor or is the machine not capable of holding a .006 tolerance? Any real suggestions? I am not looking for a website. Thanks.
2006-11-23 03:47:20 · 2 answers · asked by dprut 2 in Science & Mathematics ➔ Engineering
Your material is moving while you cut it. You are setting up a "wave", which you push with your cutter. The point at which the cutter rolls "over" the wave is the point you are seeing as run-out.
If you would like, a print would be helpful in determining a solution. It is counter-intuitive, but taking a bigger bite during your cut might help; if you are taking too small a depth of cut, your cutters may be trying to grind, rather than truly cut. This will cause the problem you are seeing. Also, if you can adjust the rake of the cutter, this will help. You want a positive rake here.
info@HaysEngineering.com for more detailed help.
2006-11-30 02:57:28 · answer #1 · answered by www.HaysEngineering.com 4 · 0⤊ 0⤋
create a new tool use 2" tool steel to make an arm to hold two or three cutters to cut at the same time its tricky but can be done remember to hog out the part first then fine cut it with this double or triple cutter last to bring it into tolerance i can keep that type of head in .001 tolerance when i did work for insulfab on the star wars project before the scraped it good luck use extra coolant jets and slow down the lathe or it will chatter enough to kill you the two or three heads will keep the right tolerance two cutters are easy to set the tolerance three is a little tricky if you have to make a lot of parts this way use the two cutter head its cheaper and you can check the cutters faster for loss or chips or you could turn the can around and cut in from the other side and make a screw on cap for easy access to motor components
2006-12-01 02:06:41 · answer #2 · answered by botany128 1 · 0⤊ 0⤋