Consider all of your machinery as well. Sometimes a part can be made simpler and stronger by machining in two parts, then welding or brazing together, or sometimes a difficult lathe operation is easy on a mill. Sometimes a slot can be filed faster than workholding to machine it, etc. I sometimes find myself fixated on the machine in front of me, when the simple solution is off to one side.
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Lathe Order Of Operations?
- Thread starter mzvarner
- Start date
Agree with the above. Main thing on the lathe is to do all your stuff to your workpiece while it is still in the chuck, i.e., don't be taking it out, doing something else to the work, then putting it back in. Unless you have to, for some reason, and accuracy isn't too important for that project. Then it's ok. As mentioned, it's hard to get it back in the exact same spot if you take it out of the chuck, or even loosen and then re-tighten it. So plan your operations so you leave it in place until finished with that end of the work, if you can.
- Joined
- Jul 10, 2013
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If you are not sure of the order of machine operations, try making the item out a cheaper material. It may take longer, because you will have to do it again. However, its better than having to order some more expensive material.
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- Apr 12, 2015
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All excellent comments. I cannot add, except to say that when I first started machining, tool changes, material handling, etc were wearing me out. A lot of needless steps. You start to learn fairly quickly what you should of done after you have done it the hard way a couple of times. I like to plan out the part I need to make and visualize how I will machine it. Since adding my mill to my shop, it has changed how I tackle certain jobs and certainly what I do on my lathe.
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- Jan 18, 2016
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Totally agree
- Joined
- Sep 29, 2014
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- 2,102
It will come with experience, the more times that you do it the easier it becomes.
I did 4 identical parts last week, 9 1/4" OD X 1" wall steel tubing 56" long.
1 Rough turn OD to 9.100 held internally in a 3 jaw and the tail stock end held with a plug, 4 each 300+ LB parts.
2 Put steady rest on lathe and face one end and bore to 8.00 diameter .5 deep, turn part 180° face other end and bore to 7.825 X 1.25 deep, turn a 20° included angle taper on this end 1/2" long, once again on 4 parts.
3 An end cap with a rough bore is then welded in one end, then it goes back into the lathe and the end cap is finish bored and the part faced to finished length.
4 It then goes into a milling machine on a spacer where a 3" Dia. hole is milled 180° apart one having a 2" wide X 3 1/2 long slot for another weldment to fit through.
5 After the cross tube is welded in it goes back in the lathe for the finish OD turning. 8.992-8.995 diameter, a 6" portion of the center where the crosstube is welded in is undercut by .010 because you can never get a decent platable finish turnining over the holes and welds.
6 Back into the mill and the cross tube bores are finished and some 1/4 NPT tapped holes are added
7 Off to the plater for hard chrome where the OD finishes at 8.998" +0-.002
This takes roughly 60-70 hours between my lathe work and someones mill work, you will notice that the parts have to be put in a lathe 4 times, end for
ended once, welded twice then set up in a mill twice. Also they cannot be scratched near the end as they are hard chromed last.
Roughly like this
I did 4 identical parts last week, 9 1/4" OD X 1" wall steel tubing 56" long.
1 Rough turn OD to 9.100 held internally in a 3 jaw and the tail stock end held with a plug, 4 each 300+ LB parts.
2 Put steady rest on lathe and face one end and bore to 8.00 diameter .5 deep, turn part 180° face other end and bore to 7.825 X 1.25 deep, turn a 20° included angle taper on this end 1/2" long, once again on 4 parts.
3 An end cap with a rough bore is then welded in one end, then it goes back into the lathe and the end cap is finish bored and the part faced to finished length.
4 It then goes into a milling machine on a spacer where a 3" Dia. hole is milled 180° apart one having a 2" wide X 3 1/2 long slot for another weldment to fit through.
5 After the cross tube is welded in it goes back in the lathe for the finish OD turning. 8.992-8.995 diameter, a 6" portion of the center where the crosstube is welded in is undercut by .010 because you can never get a decent platable finish turnining over the holes and welds.
6 Back into the mill and the cross tube bores are finished and some 1/4 NPT tapped holes are added
7 Off to the plater for hard chrome where the OD finishes at 8.998" +0-.002
This takes roughly 60-70 hours between my lathe work and someones mill work, you will notice that the parts have to be put in a lathe 4 times, end for
ended once, welded twice then set up in a mill twice. Also they cannot be scratched near the end as they are hard chromed last.
Roughly like this
- Joined
- Jan 2, 2014
- Messages
- 8,854
Agree with above, but I'll add one tip:
In my early days I would do simple little sketches of all operation steps showing how it was held....even for simple parts.
Eventually you'll find you can just walk it thru in your mind.
For more complex parts I may still do some sketches.
-brino
In my early days I would do simple little sketches of all operation steps showing how it was held....even for simple parts.
Eventually you'll find you can just walk it thru in your mind.
For more complex parts I may still do some sketches.
-brino
- Joined
- Sep 29, 2014
- Messages
- 2,102
Today's mistake, made 2 of these parts, 2 3/8 OD X .885 wide with a .190 Rad. groove with a minor Dia. of 2.125 and a .063 X 45 Deg. chamfer on one end, the other end has no chamfer. I put the chamfer on the wrong end and had to make them a second time, order of operations brain fade.
Small aluminum parts so no great loss. Took about 1 1/2 hours to make the first 2 wrong and less then 1 hour to make 2 correctly as the set up and programming was already done (-:
Small aluminum parts so no great loss. Took about 1 1/2 hours to make the first 2 wrong and less then 1 hour to make 2 correctly as the set up and programming was already done (-: