The Home Machinist!

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Looks familiar.

The dimensions represent length and diameter.

Not slit like the TG's I have.

Soft copper isn't very nice to machine in the first place, but an ultra sharp tool helps a lot.

I have also seen many times where using milk as a cutting fluid supposedly works very well when machining copper. You might want to clean things up really well after though!

Most yellow metals will "self feed" if pilot drilled.

You can reduce the rake on the cutting edge of the drill to eliminate that issue. Well worth the trouble if you are doing a number of parts or work with these alloys a lot.

Bill Shields wrote: ↑Sat Jan 20, 2024 3:59 pm actually...if the wiggler is not rotating, it will not make a difference where the point is relative to the center line....

the DTI will stay stationary

That makes sense!

Thanks!

I don't see this. If the chuck is adjusted so that the wiggler does not move when the chuck is rotated (according to the DTI), it seems to me that the point of the wiggler must be on the lathe's rotational axis. I don't see that the shape of the wiggler matters in any way. If the point is not conce...

Harold_V wrote: ↑Fri Jan 19, 2024 5:28 pmSo then, how did they create such pistons years ago?

The ones I am familiar with from the '40's were ground on the O.D to achieve the ovality and taper required. .005" ovality, and .005" taper, so fairly easy.

But them there is Honda, taking it to an extreme!

DTI's don't always read the same when you turn them upside down.

It's that gravity thing again.

Good news!

I was about to give in...

If you could post an image of the lathe I'm sure someone could help.

There are lots of generic Taiwanese lathes out there that were marketed under various names.

Harold_V wrote: ↑Sun Dec 10, 2023 6:12 pm Certainly not strong enough to overcome the (limited) tensile strength of grey iron, let alone ductile iron, which is generally the material used for cranks.

Forged steel with hollow journals in this application.