Gap when Half nuts are closed

[joebiplane]

Hey folks
In a 9" SB Workshop when the half nuts are closed is there abit of a gap between the two halves ot do they fit tight against each other ?

second what can strip them out in 10 or 15 seconds ? this happened to a friend when he engaged the half nuts.
They jumped around and the result was they were cleaned out in very short time 5-15 seconds

Any thoughts ?

And are the remanufactured half nuts sold on e- pay are brass or bronze threads in OEM units worth the money ($ 150.00)

Thanks , Joebiplane

 

[joebiplane]

picture show the damage

 

[loggerhogger]

Is it possable that he had the carriage locked when he engaged the half nut? Common mistake. If the half nut is engaged, the lead screw is turning and the carriage cant move, something's gonna break.

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