Bridgeport stuck feed nut

I'm splitting my feed nuts due to the very large and very annoying amount of backlash. I've bottomed out the adjustment screws as well. Y axis was a simple but the X axis nut will not come out. I'm trying to avoid removing the table if I can. I've tried pulling, prying, and using the lead screw to pull against the nut to try and get it out with no luck. The original adjustment screw was replaced by a hack job and the set screw was also missing. Anyone have any fixes for this besides heating up the feed nut housing? Don't want to go heating up cast iron but I don't see many options.

Also, anyone have a hardware fix for replacing the lock and set screws without having to order them? They are pricy for what they are.

figured it out. Found a ground down cap screw in the oil nut hole of the feed nut assembly. There doesn't appear to be a screw in this hole in the parts diagram.

Thread's a couple weeks old, but just thought I'd mention in case you are still interested. I drilled and tapped that hole in mine, when I had it apart. I had read here there is no reason to have that hole with an auto oiler, which has lines to the feed nuts. The hole just allows more dirt/shavings to get in there, so I plugged it.

Someone may have done the same thing to yours, but it sounds like the cap screw drifted down or someone screwed it in too far (probably worried the head of the capscrew might hit the bottom of the table).

I made my own custom cap screw to plug that hole. Basically a tapered machine screw with a slot for a flat screwdriver. The head of the screw sits flush with the top of the feed nut housing. Clears the bottom of the table and won't drift in the hole. I used a bit of locktite to make sure it didn't back out on it's own, but that part probably wasn't necessary.

@RandalThor Whether you have an auto lube system or not isnt what would make you need/not need that hold to oil the screw/nut. How are you getting oil to you nut? Are they ballcrews so the lube gets injected directly into the nut?

Jon

Hi Jon,

The housing for the brass nuts has holes to feed oil to the nuts. The auto oil lines go in those holes. When I bought new brass feed nuts (from H&W) I drilled oil holes in the nuts to make sure they matched the holes in the housing. So the oil goes from the oil lines right through the housing, through the nuts and to the feed screws. So the big manual oil hole on the top of the housing was no longer needed.

I can't remember for sure, but the brass nuts I bought from you may have had holes for oil passage already in them, but if they did, they didn't quite match the holes in my brass nut housing. I just remember having to measure very carefully to drill holes in the nuts.

Learn something new everyday... As the DRO/power feed guy here, I don't deal much with the nuts and yokes. Barry just told me that there are some yokes from BP that had the oil lines way up near the front and that sometimes you do have to drill into the nut. I had no idea lol

Ah so it was an old zerks yoke. That makes sense.

Normally when I am dealing with lube and the screws, its on a CNC retrofit so I am just not as well versed in that stuff.

Jon
H&W Machine Repair