Bridgeport questions

I have a J head B`port with step pulleys that Im in the process of trying to get going and have some questions. The speeds for high and low are listed on a plate on the front of the head, Im not sure how they correspond with the pulleys. Meaning, is the smallest pulley on the motor the highest speed or the lowest speed? I have a friend who is going to hook it up to the phase converter and I want it in the lowest speed in high range. Also, when in low range (back gear) is it true the spindle turns the opposite direction? Forward is actually reverse? I want to make sure we have the direction hooked up correctly. Sorry for the basic questions, but its been a long time since I ran one. Thank you, Craig

Reply to
monkers
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I forgot this on the other post. When changing to low range, there is a clutch handle on the top of the head that is supposed to be moved to the right. My question is how far does it actually move? Mine goes about half the distance of the slot in the outter ring of this assembly, should it be going all the way to the end of the slot? If so, what would be keeping mine from traveling the full distance? Thanks again, Craig

Reply to
monkers

On pulley drives if the pulley that is driving is the same diameter as the driven pulley the speed will be the same as the motor.

If the driving pulley is larger than the driven pulley, then the speed of the shaft that is driven will be faster than the motor. If the driving pulley is smaller then the driven pulley then the shaft will be slower than the motor.

When you have a Bridgeport in low range the switch will operate in reverse.

Keep an oil can handy and keep your oil cups filled.

Reply to
Roger Shoaf

Reply to
RoyJ

and be sure to change the Low/high Range lever in the proper position thats located up on TOP of the head. Makes for stinky shop if you get em wrong as the belt squeals

Gunner

Rule #35 "That which does not kill you, has made a huge tactical error"

Reply to
Gunner

Smallest motor pulley is the lowest speed. I have a friend who is

Yes.

Jon

Reply to
Jon Elson

It should go all the way. Check that the ring-cam is not cracked. If cracked, it can usually be brazed and will serve for years. Check the pins to make sure they don't wobble in the piece they screw into. If so, make new pins on a lathe, with a larger thread, and re-tap the piece they screw into. Mine goes

If it doesn't go to the right and back, that is what you need for low-range. Something must be sticking. Mahe sure the spindle brake is off. That is the little handle right on top of the belt housing. To go to low range, the cam ring lifts the pulley by its bearing set through the pins. The bearing assy must be free to slide upwards. There is a big spring in there, too.

If it doesn't come back to straight forward (high range) then something is preventing the pulley-bearing from moving down, or binding the cam ring. The dog clutch should not jam the cam ring, it will just ride up until the clutch dogs engage, then the pulley and all will drop down with a clunk. You can do this by twisting the spindle with your hand.

And, of course, it may just need cleaning and oil.

Jon

Reply to
Jon Elson

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