- Did you try to match the diameter of the tool to the bore?
- What grit paper did you use?
- How much taper was there before you started cleaning up the tool marks?
Lapping a small bore
Re: Lapping a small bore
Great story! As a fellow tightwad with too much accumulated junk, I can relate. Some serious questions:
- Bill Shields
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Re: Lapping a small bore
I am a bit concerned that anyone would think about ball burnishing using the tailstock of a lathe..
.very much a nono on any lathe
My experience is that this type of process is done in an arbor or hydraulic press..never in a lathe (of any make).
The results from your 'eurika' moment are impressive
.very much a nono on any lathe
My experience is that this type of process is done in an arbor or hydraulic press..never in a lathe (of any make).
The results from your 'eurika' moment are impressive
Too many things going on to bother listing them.
- Greg_Lewis
- Posts: 3010
- Joined: Wed Jan 15, 2003 2:44 pm
- Location: Fresno, CA
Re: Lapping a small bore
It is under by about the thickness of the paper plus a fudge factor of about .005.
400. I should have used cloth-backed as the paper tore a bit at the outside end. I think that may be what caused the .004 taper. It and the bore were also sprayed with WD40, some of which remains on my shirt and the window behind the lathe.
Dunno. Didn't think to measure.
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
- Greg_Lewis
- Posts: 3010
- Joined: Wed Jan 15, 2003 2:44 pm
- Location: Fresno, CA
Re: Lapping a small bore
Bill Shields wrote: ↑Sun Sep 25, 2022 7:58 pm I am a bit concerned that anyone would think about ball burnishing using the tailstock of a lathe..
.very much a nono on any lathe
My experience is that this type of process is done in an arbor or hydraulic press..never in a lathe (of any make).
The results from your 'eurika' moment are impressive
If I'd done the bearing ball thing I would have done it in the hydraulic press. The ball-bearing burnishing would have had to have been done in the lathe with the bearing on a rod in the toolpost. There is no way my wimpy lathe could do that. It complains about any cut more than about .030, and even though it's mounted on 1/2-inch plate, I can put a dti on the chuck and watch said dti move when I push on the headstock. And everything is bolted down tight. If the moon's gravity is right I can get results to .0001 but that's rare.
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
Re: Lapping a small bore
Another job adequately done!
RussN
RussN
- Greg_Lewis
- Posts: 3010
- Joined: Wed Jan 15, 2003 2:44 pm
- Location: Fresno, CA
Re: Lapping a small bore
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.