I would try this kind of question over at Practical Machinist and the 
Old Woodworking Machines forums. Of course, someone here might be of 
help and reply - I sure don't know the answer, but those are the two 
places I would go for folks who almost certainly do.

- Bill T.

On 5/14/2012 1:33 PM, Paul Gardner wrote:
> GG's
>
> Apologies for the off charter nature of this post, but since many
> Galoot denizens are problem solvers by nature,  I thought I'd throw
> this out and see if any spiffy ideas come back.
>
> My father has a Taiwanese vertical mill (Bridgeport clone bought
> second hand) that has acquired a problem. Having dropped it in a low
> gear for a routine operation, he found that he couldn’t back it out
> again.
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