disassembling Bridgeport or Kondia PowerMill - how hard to remove head and table?

On 10 Dec 2003 16:25:16 -0800, T.Inoue put forth the notion that...

Removing the head and the turret are pretty easy, but they're still heavy. I'm guessing a J-head weighs in at around 250-300 pounds with the motor. You can pull the ram off the turret pretty easily, but you'll probably need a cherry picker or something to lift it. I've never removed the table on one, but if you can avoid it, I would.

I have good news. You don't have to remove the head. You just loosen the

4 bolts on its face and swivel it upside down. There is a 3/4" bolt which turns a worm gear to rotate the head. Be careful, sometimes teeth are stripped in there and a BP head falling over can kill you. (Keep one hand on the motor and the other on the wrench as you slowly lower it down and you'll be fine.)

To remove the table, remove the handle from one end, then lift off the dial assembly and then remove the 4 socket head cap screws and tap off the end piece. Then go to the other end and screw out the X lead screw entirely. At this point you can just slide the table off the end. Put a table or bench or something up next to the mill, adjust the knee so the height is right, and just slide the table off. Two guys can carry the table. The rest of the mill can easily go through a door 28" wide and 74" tall - I've done it! Here's a picture of a mill ready to move. Note the plywood on top of the knee - after you remove the table, it's a good idea to snug the knee up under the head with plywood in there.

One cautionary note: when moving one of these on a truck do NOT rely on the knee not moving down to keep a strap taut! That's how you tip over a BP mill ..

Grant Erw> I'm looking at potentially getting one of these machines and in order

To elaborate, the failure mode apparently is that if one straps or chains a b'port down, with the binders over the table, the elevating screw can strip its nut and that allows the knee to fall down, and loosens the straps or chains.

Machine is then free to, well, free-fall.

Jim

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Grant Erwin wrote: snip

Not a problem if you put a block under the knee...

I know the Bridgeport pretty well. It will actually fit through a narrow doorway with a trick. You pull the door off. You crank the table all the way to one end, and all the way back toward the column. Then move the machine up to the door at an angle, and crank the table all the way to the other end, and then use the Y crank to extend the saddle away from the column. You should be able to then swing the machine into the other room. I think I did this with a 30" door! You may have to remove one or both handles in some cases.

The head is fairly easy to remove in 3 pieces. This applies to the

1J head, with the 4 belt grooves. There may be some differences doing this on the varispeed (2J). First, remove the motor. 2 bolts hold the motor to the belt housing. 2nd, there are 3 nuts just below the belt housing that secure it to the main head casting. Remove the nuts, and you should be able to pull the belt housing straight up and off the spindle splines. Now, the main casting and quill are REALLY heavy, amybe 150+ Lbs, and nothing good to grab it by. You can use the table and a wood block to support it. There are 4 nuts on the front of the casting that hold it on by t-bolts. Remove the nuts, and be ready to grab the housing and slide it off the bolts. (When reassembling, those nuts are to be tightened to 50 Ft-Lbs, +/- zero. Nice spec., that's exactly what it says in the Bridgeport manual.)

Really, don't remove the head unless you have to. It can be tilted on its side easily to clear the doorway.

Jon

Yes!

gunner

The methodology of the left has always been:

1. Lie
2. Repeat the lie as many times as possible
3. Have as many people repeat the lie as often as possible
4. Eventually, the uninformed believe the lie
5. The lie will then be made into some form oflaw
6. Then everyone must conform to the lie

Yes again! and recommended even if strapping over the ram. Thats one heavy chunk of iron to be bouncing on a trailer. Always block the knee on any mill etc before driving very far.

gunner

The methodology of the left has always been:

1. Lie
2. Repeat the lie as many times as possible
3. Have as many people repeat the lie as often as possible
4. Eventually, the uninformed believe the lie
5. The lie will then be made into some form oflaw
6. Then everyone must conform to the lie