[Aello]

Hello everyone, this is my very first post and I am, as many others, here to humbly ask for help, or a little clarification.

I am the owner of a Sherline 5100 (metric) milling machine, which I bought second hand. With (little) time, I've noticed some missing parts from the original exploded, so I decided to buy them, along with the replacements for some very worn parts.
So I bought:
- 1 Y-axis backlash nut
- 1 Y-axis nut
- 1 X-axis backlash nut
- 1 X-axis nut
All of them metric, as I measured my axis screw and verified its being metric.
Here comes the issue: I can't get the X-axis screw to fit in any of the nuts, and I believe the same will be for the Y.
It doesn't completely unfit, it does 5-6 spins and then gets hard as hell, like the nut was rather convergent, then a straight cylinder.
And it actually seems to be so, since looking at it from one side I can see some inner surface, while looking from the other I cannot. So how should I handle this? Is it meant to be so? To be forced to spread inside its fitting by the screw itself, or rather by another tool?
Every help is appreciated!

Inviato dal mio GT-I9100 utilizzando Tapatalk

[Fastest1]

Sherlines have had a variety of screws in metric and imperial. A 6mm is awfully close to 1/4-20 so is the odd 6.3mm (I say this because I have a lead screw I am trying to retrofit to my lathe, that is oddly enough 6.3, it is not a Sherline original part). Then there are left and right hand threads. Probably cheaper to go ahead and buy the screw itself that matches your new nuts at this point, 24 bucks?

[Aello]

Now that you mention it, yes when I was measuring my screw in order to define its being metric or imperial, I noticed that apart the pace, clearly metric, its size was 6.3, which was pretty odd. So you are telling me that the replacements I bought are for a newer 6mm screw, mounted on later versions?

Inviato dal mio GT-I9100 utilizzando Tapatalk

[Fastest1]

Not really. The 6.3 I was using is actually a Haydon Kerk leadscrew and anti backlash nut I am going to make work on this lathe. It does thread into a 1/4-20 nut that Sherline sells. This screw has a Kerkote coating so it is bigger besides being proprietary most likely. I have no intention of using the nut Sherline uses in this future set up as it is a preloaded set of nuts in Delrin or some other super plastic. It was just an observation that it did indeed thread in completely. The major diameters are probably the same.