The Bridgeport here at the shop is making a really obnoxious noise when lowering the knee. I believe it is a series I with the 2J head. The sound is like a resonating/high pitched whining sound and only happens when cranking the knee down. I regularly pump the centralized oil dispersion pump to keep the ways oiled. Any suggestions?

http://img.photobucket.com/albums/v94/YJTypeR/0821090926.jpg

I don't own a BP, but:

1. It's possible the knee screw needs to be lubed separately.

2. Sometimes the individual lube lines get clogged.

Squirt some lube on it and see what happens.

Try snugging the knee lock before lowering ... our shop has a shit load of BP's and ever one does the same thing.... from one year old to 30+!

Don't lock it down just create a drag , helps keep the weight of everything from overrunning the knee screw.

If the noise is reduced by doing this then a small gib adjustment might be the answer.

Jeff

On some models there is a grease fitting on the brass nut that moves the table up and down.

Our 3 BPs do that too. It doesnt really bother me much and my boss is going def so I don't think he even hears it. We were going to try to cut a handle up and weld it to something that we could put on the impact and make raising and lowering the knee a lot faster. Seems like when we lower it faster the noise goes away or atleast fades some.

Yep, common trait with BP's. Grease the ball screw & use thicker way oil. Still not a gaurentee it will stop it. Slight drag may help as was said. When you mill do you lock the table lock. I ALLWAYS drop the table a couple of cranks lower then what I need, then crank it back up a couple of cranks then lock the table. You want to try to keep small chips from getting in between the knee and base ways. That does not help the situation.

Have you checked the gib adjustment?

Does not hurt to squirt some way lube on the knee screw.