Bridgeport Mystery

D

dfletch

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In Dec. 2012 I decided to retire and moved my remaining machines home, among them a Bridgeport 2J Varidrive. For the move I removed the head from the ram, laid it on it's side, and strapped in down on some cardboard and blocks in the bed of my pick-up. Once home I reinstalled the head and set up a VFD to run the machine on single phase. While testing I find a dowel pin laying in a tee slot on the table that I swear was not there when I cleaned the machine before the move. The pin measures 2" X .625" and I find no reference to such in the manual. I'm thinking it could be a pivot pin for the head to swivel from side to side or it doesn't belong to the machine. I haven't removed the head to check. That's part of the mystery.

Sense then I have not used the mill, only running the motor every 4 to 6 months in an apparently unsuccessful attempt at preventing the belt from taking a set. Now I am wanting to get it running for a project and I discover that there's a problem with the quill feed. I can only remember using quill feed 2 or 3 times in the 15 or so years I've owned the machine but it worked. What I now find is the quill feed selector which normally has three positions, up, back towards the motor, and down now is pointed forward away from the motor and will only move about 15 degrees down. In the forward position the quill moves but can be stopped with a little pressure on the hand wheel as if being moved by friction rather than a positive engagement. During the move the head remained stationary so I don't believe the lever was hit or was under any pressure. I will remove the cluster gear cover for a look before tearing it down. Any ideas would be appreciated.

Doug
 
dfletch said:
In Dec. 2012 I decided to retire and moved my remaining machines home, among them a Bridgeport 2J Varidrive. For the move I removed the head from the ram, laid it on it's side, and strapped in down on some cardboard and blocks in the bed of my pick-up. Once home I reinstalled the head and set up a VFD to run the machine on single phase. While testing I find a dowel pin laying in a tee slot on the table that I swear was not there when I cleaned the machine before the move. The pin measures 2" X .625" and I find no reference to such in the manual. I'm thinking it could be a pivot pin for the head to swivel from side to side or it doesn't belong to the machine. I haven't removed the head to check. That's part of the mystery.

Sense then I have not used the mill, only running the motor every 4 to 6 months in an apparently unsuccessful attempt at preventing the belt from taking a set. Now I am wanting to get it running for a project and I discover that there's a problem with the quill feed. I can only remember using quill feed 2 or 3 times in the 15 or so years I've owned the machine but it worked. What I now find is the quill feed selector which normally has three positions, up, back towards the motor, and down now is pointed forward away from the motor and will only move about 15 degrees down. In the forward position the quill moves but can be stopped with a little pressure on the hand wheel as if being moved by friction rather than a positive engagement. During the move the head remained stationary so I don't believe the lever was hit or was under any pressure. I will remove the cluster gear cover for a look before tearing it down. Any ideas would be appreciated.

Doug
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Doug, for some reason I am thinking that the pin you found in the slot of the table is the locking pin for the head. This pin is on the left side of the head and, since the head is so top heavy, prevents the head from spinning more than 20+ degrees without a conscious decision from the operator.

Regarding the quill feed, it seems strange that quill feed selector moved because the head is completely independent form the rest of the machine. The only thing is between the two is the four lug nuts that hold the head in place.
 
A 2 x .625 dowel pin would be the size that you would use for aligning something to the T-slots. I'm sure it was just laying in there. There is no pin of that size in a BP.

I would pull the shift lever cover off and re-align the pin with the selector inside. I don't think that there is a real big problem there.
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You have got 4-5 things/handles/levers to play with to get the quill feed to work. First, you need to engage the feed with that lever on the right side of the head. If you don’t do this, nothing will work. And it will be impossible to change speeds because the feed gears are not turning and can’t mesh. That’s why the lever you are talking about will not work as it should. Please read you manual…Good Luck, Dave.
 
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I thank everyone for the replies. I did check all of the devices I have that use alignment pins and none are missing. I have read the manual just to be sure of the correct operation of all the levers. The quill feed selector is way out of any normal position but the quill will still move both forward and reverse, one speed and neutral only. I will have more time to check it out this week. Once again thank you all for the replies.

Doug
 
The shop gremlins put that pin there I tell ya. The little suckers come out when it is dark in our shop. And they move things around and hide things. They like playing games like that to make us think we are going crazy.



Really I have no clue. But I swear them gremlins are real.
 
That speed selector lever can be moved into a strange area/position making you think something is wrong/broken. But I do not think you have any big problem. Changing the speeds with that lever can be finicky. Just make sure you have the feed engaged with the other lever on the right side of the head. Then with patience, try moving that speed selector lever. It may not “just go in”, you might have to play with it to get it into that hole/position of choice.


And tell me about those Gremlins! I don’t want them in my garage anymore! Someone else, please take care of them for me.
 
The T-slots are 5/8". Pins are used for quickly setting something parallel to the "X" axis. I have several I use for quick setups. Bang 2 of them into a T-slot, put a parallel against them and indicate it. You will find that it is pretty parallel to the axis. Just pry them out when you are finished. They are great for quick set-ups.
 
Found the problem , I think. Pulled the side cover with the quill feed selector and found the sliding block that is supposed to straddle the sliding gear was disengaged. The gear was sitting on top of the block rather than in the slot. Put it back together and every thing worked as it should. Just looking at the way everything works it doesn't appear as tho that could happen. The selector handle own my machine will move forward past the vertical and that's the way I found it after the move. My guess is that combined with the head laying on it's side allowed it to happen. Seems like there would be a stop to prevent the handle from moving that far but if there is it must be broken on my machine. I plan to explore further.
Yes I know about them Gremlins! Thanks for the tip Jeff, that will come in handy. Now if the Gremlins will leave me a second pin I'm set.
 
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