Into the Head - Bridgeport 2J2 Variable Speed

[ctwo]

I'd love to, Ken. I'm hesitant in my skill in properly dismantling and assembling the spindle correctly (more worried about breaking something along the way...), and I'm already over what I wanted to spend getting the machine running, still need a few items, including the big Erickson spindle "nut" for ~$250. Spindle bearings look to be ~$300 to $500 depending on quality and a few other unknown to me parameters. It is hard to stop twisting the nuts and bolts though...

I still have not taken off the housing shown at the top of page 2 of this topic, because the alignment procedure still evades me. However, I would like to bust into the quill drive and check that out. I was saving it for another time, unless I get so inspired at this most opportune moment.

[stevec]

the big Erickson spindle "nut" for ~$250.

ctwo, I hesitate to ask but, have you not considered making the nut yourself?

[ctwo]

I will give it a shot. The actual nut is fine, just the inside piece that actually holds the tool holders is chewed. It's not too complex a piece, but just hard (for me) to get all the dimensions just right. I believe they will need to be within a few tenths for it to actually work, and made from a relatively strong steel. It is like a ring with two outside and two inside faces that must all be within spec.

[Harold_V]

I will give it a shot. The actual nut is fine, just the inside piece that actually holds the tool holders is chewed. It's not too complex a piece, but just hard (for me) to get all the dimensions just right.

I expect that the insert you speak of is heat treated, and would not function properly over the long haul if it was not.

Harold

[ctwo]

It may even be heat treated and then ground. I'm sure a few days banging my head against it will convince me that the $250 "nut" is really a good deal after all...

You guys will likely be the first to know when I get around to it.

[ctwo]

BP spindle bearings are OIL lubed ,constant loss system . You squirt oil in the one port daily and it runs down through the bearings .

Hi Guys. Does anyone know for sure if the CNC Boss3 with the knod/tilt head has sealed or oiled bearings? My head has a label that says do not oil because it has a grease packed head, but there is an oil line from the auto oiler that goes in about where the Z-axis drive belt wraps around the quill, and it gets oily. The spindle bearings feel dry, but that might be a normal feel for them.

I'm just hesitant to tear it down further because I have not found any directions or illustrations on this head configuration, and it all seems to work just fine as it is.

The worst case is that the spindle bearings need oil and the oiler is not getting it all the way down where it's needed, or the bearings are sealed and they've dried out - both cases resulting in burned out bearings which are now tight and very smooth running.

[ctwo]

This looks like cast...

[Russ Hanscom]

Most likely not cast but heat treated and left hard and brittle.

[ctwo]

OK, not so bad...at least now it's straight!

[ctwo]

While cleaning out the old grease inside the head, I found a row of small ball bearings just sitting on top of the quill.

I can only imagine they came from the quill ball screw, but how? Could that happen if the quill was over extended? It does not seem possible. I can see a lock ring in the quill that would seem to prevent that from happening. I suspect the ball screw could still function if it was missing some balls, but it surely would not be good.

[ctwo]

I have come to discover that if someone had removed the quill stop/guide bracket, then the quill could be over extended allowing the ball screw nut to come off the end of the ball screw. And that is exactly where the balls would end up, right on the top end of the ball screw where I have some sitting in grease.

[ctwo]

I pulled the ball screw housing off. Any advise on inspecting the screw, what to look for? How to tell if these loose balls came from this screw before I mess up something that's not? How many balls should it have?