Author Topic: Harrison 140 lathe question  (Read 3495 times)

Offline hanermo

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Re: Harrison 140 lathe question
« Reply #25 on: March 11, 2017, 11:13:08 AM »
This may be so, but I think, honestly, not..
All sorts of lathes by thousands have been used on ships and boats of all types for decades and worked fine.

As you said, if it has an accurate-to-lathe-body (spindle) subframe, this will be a great help, and You can just move it / chuck the subframe into any place and it will be fine.
No personal experience on that lathe.

But boats/yachts/ships twist, quite a lot, in machinist terms.
This does not hurt any lathe, but for top-accuracy the lathes should theoretically be soft-mounted on relatively rigid subframes.
Afaik, this is not routinely done.

A huge nr of manual lathes are on soft mounts and do excellent work.
The common wisdom and factory recommendation on manual lathes is soft mounts.

I am not advocating/insisting on soft mounts ...
just pointing out they are the common-average factory recommendation, and work well.
A hard mount is modern practice with big cnc turning centers (+vmcs), that are all soft and floppy, volumetrically.


Worth noting the 140 was designed to go on the back of a Army or Air Force 10 ton Truck or in the engineering shop of a ship, frigate or battle ship. So leveling is not essential but preferred.
That is why it is Near fatal to ever part the lathe from the special frame it is bolted to.
For that reason it is the only lathe I know that can be put on wheels and still stay accurate.
Mine is on wheels ! I posted a pics long ago
Trev

 :)

Offline Biggles

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Re: Harrison 140 lathe question
« Reply #26 on: March 11, 2017, 03:08:59 PM »
Not too sure of all models John. My old L5a you can engage both if you so wish. Having said that, there are security shear pins, one is the connection between the cross slide screw and gearwheel and the other is in gear box. (Havenít seen this one though). There could also be another in the saddle. (For those not in the know these taper pins are made of mild steel and designed to sheer when excess force is applied to the machine mechanisms) (Obviously donít mean you John  :bow:).

Offline Ian.C

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Re: Harrison 140 lathe question
« Reply #27 on: March 14, 2017, 02:38:21 AM »
Thanks again chaps. I'm attempting to make a 3C collet block!

Offline Biggles

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Re: Harrison 140 lathe question
« Reply #28 on: March 15, 2017, 01:35:12 PM »
Good on you Ian, lots of pictures please.  :thumbup: