Pultra 17/70 crosslide feed screw nut


NAWCC Member
Oct 18, 2019
In the cotswolds UK
Had to do some running repairs on my Pultra crosslide as the crosslide lead screw nut had worn, when I took it apart I found I could slide it up and down the lead screw without even having to turn it, there is adjustment to take up the slack but all the adjustment does is put a slight twist on the nut putting it at an angle and that will only work so many times and a prerequisite is it has to have some thread in the nut.
A nice friend thinks he has one but is unable to find it at the moment, even if he can find it will it be metric or imperial, my crosslide is imperial 1/4" X 40 tpi one full revolution of dial = 0.25" and as I need to use the lathe I needed to make a running repair, I couldn't use the lathe because I couldn't fathom a way of holding it so I put it in the mill opened the hole to 7mm with an endmill but I could still go a fraction bigger but not much, I ended up going to 9/32" ( 7.14mm ) not much more but I wanted as much of the bush wall as possible, I then turned a bush on the lathe to be a very tight fit using a graver and with a 3mm hole ( easier to get hole central in lathe ) for me anyway, pressed it in and drilled hole to 5.5mm for tapping, I started to cut thread with the tap and promptly turned the bush out so a rethink was in order, as I had some silver solder paste I decided to solder it so after cleaning it up I wiped a small amount of the paste around the bush and pressed it back in and heated until the solder flowed, well that did the trick finished the thread cleaned up and put everything back together and no play whatsoever.
But this is only a temporary fix if My friend can't find the one he thinks he has or decided not to sell it then I need to make a new replacement, but what to make it out off brass or bronze if brass what brass, if bronze what bronze ?.
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