Bridgeport Mill Head jammed

[Doug Arthurs]

Seems to be a lot of mill threads lately so I thought I would start my own. I have an old Bridgy had it for maybe 8 years. Its pretty worn but I still get good parts from it. One day I hope to get a good deal on a replacement thats heavier duty but for now it works. One problem I have had from day one is the ram is jammed. I have sprayed penetrating oil in and around it but never been able to get it loose. Of course I loosen the lock bolts but it won't move. Somebody prior to me broke the handle off you use to move it. Does anyone have any experience with this. There really aren't any good spots to put a homemade press in order to break it free. I am not sure if the ram is jammed or the locking bolts aren't releasing.

 

[WhoWhatNow]

This is probably not the problem but what are you using as a handle to move it. Mine had a 2" bolt as a replacement handle and even with the bolts loosened completely it was really hard to move. Replaced that with a 12" handle and it moves like butter now. Leverage is a wonderful thing.

 

[Doug Arthurs]

The handle is actually broken so I grabbed it with a pipe wrench.

 

[Provincial]

Is there any movement (gear backlash) of the handle when you try to move the quill?

There are three possibilities. First, the shaft that the handle attaches to is siezed, in which case there would be no movement or backlash at the handle.

Second, the quill power feed is not working, but engaged to the quill. In that case, the handle would have backlash, and the quill would try to move up and down slightly.

Third, the quill is siezed in the head. In that case, the handle would move slightly because of the backlash in the gears, but the quill would not move at all.

Report back with your results.

 

[larry_g]

Is there any movement (gear backlash) of the handle when you try to move the quill?

There are three possibilities. First, the shaft that the handle attaches to is siezed, in which case there would be no movement or backlash at the handle.

Second, the quill power feed is not working, but engaged to the quill. In that case, the handle would have backlash, and the quill would try to move up and down slightly.

Third, the quill is siezed in the head. In that case, the handle would move slightly because of the backlash in the gears, but the quill would not move at all.

Report back with your results.

I don't think the quill is jammed, I think the Ram he speaks of is the ram that moves forward and back changing the Y position of the spindle in relationship to the knee. But the question of backlash is a good one, does the gear/pinion shaft move at all?

Also I would ask is this a round ram machine or dovetailed, they made both?

I don't have any experience here but would have to ask, If the turret is unbolted and removed is there access to the bottom of the ram to inject magic juice to help free things up?

lg
no neat sig line

 

[Doug Arthurs]

The problem is with the ram not the quill. One of the locking bolts is actually missing the other is loose. When I try and turn the shaft to move it forward I can feel a little backlash and the shaft moves out a little if I pull on it so its not siezed. I feel like the locking mechanism inside the ram is not releasing. Also this is a dovetail machine.

 

[Doug Arthurs]

Here is a picture.

 

[larry_g]

Here is a picture.

I don't have any experience here but would have to ask, If the turret is unbolted and removed is there access to the bottom of the ram to inject magic juice to help free things up?

lg
no neat sig line

 

[rsanter]

Odds are it is grime and some rust.
If you have everything loose, I would use a good block of wood and a sledge hammer on the back side. Give it a wack and see if that will break it loose.
Actually before that you want to inspect the areas where the ram goes into the turret. Clean out any **** and spray penetrating oil along the parting seam between the two items.

Also, for that screw that someone broke off the handle.....remove the set screw that holds it in and pull that thing out.
Look in the hole for the condition of the gear teeth and inspect the gear teeth on the screw.
Then either mill some flats on the end of that screw (I have mine milled to use a 1 1/4 wrench on) or weld a large nut on the end of it. Bigger the better so you can use a big wrench on it. I always hated that little POS single position handle they came with

 

[jmarkwolf]

The dove tail ram on my Bridgeport was jammed also when I bought it. The handle was also broken off at the pinion. It had been this way for at least 6-8 years that I'm aware of.

Here's what I did.

I removed the pinion. After removing the capture screw it will just slide out. Makes a good spot for spray access for the penetrating oil. I removed the broken stub of the handle (took a little doing) from the pinion, and screwed in a long bolt (3/8in as I recall) as a temporary handle.

Bought aerosol penetrating oil with a straw and sprayed liberally every and all nooks and crannies.

I put a Sharpie mark across the seam so I could easily see it if it started to move. Then I put a couple long bar clamps on it, to apply pressure on axis with the ram. Would hate to hammer on it.

Just before I was to switch off the shop lights for the night I looked at my Sharpie mark and lo and behold it had moved a little and the clamps had loosened. I tightened the clamps again and the Sharpie mark moved more.

Then I removed the clamps and started cranking the ram back and forth with the temporary handle. At first it would only move back and forth about 1/4 inch, but eventually moved more and more. I kept spraying it and working it back and forth, and finally go it to easily move nearly full travel (about a foot total travel, or better if I recall), to the point where the underside of the dove tail is slightly damaged.

Let us know if you're successful on you ram.

 

[Doug Arthurs]

I will remove the pinion tonight and start spraying it.