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Bridgeport Series 1 Power Quill not working

TTMotorsports

Plastic
Joined
Nov 10, 2021
Ok so I have a bridgeport series 1 that i acquired recently for my shop. Now I want to use a boring head to precisely bore some items for my offroad fabrication for a light press fit, like 0-1 thou. To do this good I would like to use the power quill to get the feed rate correct fora nice finish. Everything works as it should on this mill except the power quill feed engagement lever is stuck all the way in. Now what can I do to free this up and get it working for me. The power quill little knob you can push in or out works and the large pieces spins the correct way BUT the level is stuck all the way in so I cannot get it to work.

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First off a LIGHT press fit is on the order of 1/2 thou per inch of diameter ! Second to your issue , the usual reason is dried ,gummy oil on all the moving parts of that area. Sometimes broken or damaged parts. I have got many of those gumed up BP feeds to work by washing down ALL the moving parts with a mix of ATF and acetone. The power down feed will not engage when the quill stop is hard against the top stop,pull the hand feed lever down to where the stop is oh a 1/8" below the top before ingaging power DF knob. The threaded rod the adjustable stop nuts are on needs to move freely about a 1/8" upand down once the upper stop has moved down the 1/8" or so. You need to get the free PDF parts break down that are on the web and see all the little bits that have to move freely for that system to work.
 
On mine it was the last pin at the end of the little horizontal driveline with the ball inside. This is the one that has the forward and reverse thimble at it's end, but the pin is at the farthest back end.
Buy one of the repair books off ebay, they are very good. (Rebuild Manual for 1hp Bridgeport "J Head" Mill | eBay)

You can chase the power train from where that forward and reverse thimble shaft sticks out, if its turning (When engaged) you know power has reached that far, if not then likely you need to go up, if it does turn then you need to go towards the back, but if the crown clutch isn't turning it may be that little pin.
 
Ok the little power thimble thing does turn when it is engaged in or engaged out. The previous owner said they never used the power quill so it's probably gummed up a bunch. Gonna use some atf/acetone mix to clean it which I had to use on my clausing lathe in a few spots to get that to work as well. I was hoping it was something obvious like a set screw was tight but I don't think I'm that lucky this time. Shouldn't that lever be hanging straight down and easy to move in or out normally?

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Shouldn't that lever be hanging straight down and easy to move in or out normally?

No.

The lever should be at the 5 o clock position when not engaged, and at the 7 o clock position when engaged.

The engagement piston is what you need to clean, and operate with some lubricant to free it up properly.

If this fails, there is an adjustable clutch in the downfeed mechanism that is your next object of scrutiny.

This all should be covered in your new book.
 
Ok I watched numerous videos AND i cannot get the little ball out of the wheel that spins when you engage it. So I cannot remove that piece with the lever on it. With the clutch piece removed the lever still will not move at all, even with light tapping on it with a plastic hammerPXL_20220326_181706815.jpgPXL_20220326_181655166.jpg
 
Getting that ball out will drive strong men to drink and Saints to give up religion ! The least bit of oil gum and you are SOL ! I have NEVER found a fool proof way of getting them out. About the only thing I have not tried is sticking a TIG tungsten to the ball,mainly because the tool dealers shop I worked part time did not have a TIG machine. A super stong magnet might help after soaking the hell out of it for a few days with the ATF mix.
 
How do you guy suggest getting out the small ball bearing on the quill knob so you can tear all that down.

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