Thread: Purpose of this toolpost feature?

There's a threaded 3/8" hole on one side of a toolpost.
I suppose it could be handy if I wanted to bolt something to it.
It's about 5/8" deep. I screwed a UNC 3/8 bolt in it for the photo.
Anyone know if there's a specific reason for it?

Could be to screw in a bar/lever to make it easier to rotate into a position?
Kryn

Hi Guys,

Possibly a pinch bolt to stop the eccentric sleeve from working loose ! Which shouldn't happen !

Anything in the hole ? besides the bolt.

Hard to imagine it being a fastening point used during manufacture, the only other suggestion I can think of is for an indicator mount. Did you buy the tool post new, or was it secondhand, and might a previous owner added that particular feature?
Edit.. Red face Department here, — I just went out and had a look at one I purchased recently for the lathe at our local Mens Shed, and it has a similar feature that I had not previously noticed. This one is a wedge lock design, the same size as yours, which if I am not mistaken is a piston design. FWIW I purchased this one from Mag Pro in Derrimut.

The Chinese versions of these posts were all copied from the original Aloris post. As we know, sometimes people copy things blindly without realising what they are for.
Originally, that threaded hole on the Aloris was for a tool stop -
Annotation 2019-10-26 204240.png
Aloris don't feature to stops in their later catalogues - this picture is from a 1987 version. Not even sure the hole is still there, but the copiers are carrying on the great tradition of putting the hole on the QCTP...

Michael

That looks like the answer, thanks Michael.
- and everyone else for their guesses.

Originally Posted by Michael G

The Chinese versions of these posts were all copied from the original Aloris post. As we know, sometimes people copy things blindly without realising what they are for.
Originally, that threaded hole on the Aloris was for a tool stop -
Annotation 2019-10-26 204240.png
Aloris don't feature to stops in their later catalogues - this picture is from a 1987 version. Not even sure the hole is still there, but the copiers are carrying on the great tradition of putting the hole on the QCTP...

Michael

Thanks Michael for the heads up on that one. Your explanation reminds me of a report I read several decades ago now, about a Japanese firm, Fujitsu rings a bell, but I am not too sure of that given the time elapsed since I read the article. Basically the same story as your example, the Japanese company cleverly stripped back a large memory chip, layer by layer, photographing the resist patterns and circuitry as they went. They then used these copied designs to fabricate their own chips in their own chip foundry, and proceeded to market them all over the world. Their skulduggery only came to light when the Americans became suspicious of the Japanese chips hitting the market so soon and examined one of them in much the same way that the Japanese had done their work. The crunch came when a flaw in the American design, was copied exactly by the Japanese company! (From memory 4 redundant transistors, which in the end served no purpose, and had been tied to ground rather than a whole new series of resist patterns being created, and a whole lot of chip wafers scrapped.) At the time memory was about $100 per Megabyte, so really big money at stake.