Bridgeport Rehab - or How To Lose Your Wife In 10 Days

[jmiller]

So on first the first run everything seems smooth and quiet. Spindle has under .001 runout. Power downfeed does not seem to be working and the down feed speed selector will only go into the top position.

The back gear selector only works in the "out" position and stalls the motor when "in" is selected. I think this might be a clutch issue. The clutch seams to be siezed.

Looks like I'll be tearing into the head.

 

[pontiac428]

When engaging the downfeed and shifting in and out of back gear, it helps to turn the spindle a little a little by hand to line up the dogs. If it still doesn't drop in, then yeah, time to look into it.

 

[jmiller]

When engaging the downfeed and shifting in and out of back gear, it helps to turn the spindle a little a little by hand to line up the dogs. If it still doesn't drop in, then yeah, time to look into it.

The back gear will shift in but when i torn the motor on it won't spin and quickly overloads the vfd.

The down feed lever does and worm gear do engage but the spindle doesn't move down, or up for that matter

 

[jmiller]

Yup, there be yer trouble.


EDIT: nevermind. That is supposed to be bent to lock that nut. Ill keep digging.

 

[jmiller]

I'm an idiot. But this is how we learn, right? I think I figured out the issue and the issue was me the whole time. I had removed the clutch cam assembly to remove the rust a while back. It was just sitting there on the work bench waiting to be reinstalled. So when I was shifting into low gear I wasnt able to, or even trying to, disengage the clutch. I am fairly certain this is what was locking the spindle and motor up. This is what I get for rushing. When will I learn. I dont think I caused any damage as I was quick to cut power when nothing was turning. At least I got to take apart the the pully housing, check some bearings, and give it a good cleaning. I will reassemble the top end tomorrow and give it another test run.

 

[tq60]

Turn by hand to check function as you build it.

Sent from my SM-G781V using Tapatalk

 

[jmiller]

With everything reassembled the clutch and back gear seem to operate properly by hand. However the cam ring pin screws are all buggered up. I thought I had ordered replacements but appearently not. I dont want to wait for shipping and they seem easy enough to make so it looks like I have a side project for today. Best I can tell these are M6 1.0 threads. The pins are too stripped to measure properly, but that's the screw size that I got to thread in there nicely.

 

[jmiller]

Started with some .500 cold rolled. 1018 I believe. Turned down the large and small diameters.


Tapped to M6 1.0. I turned the tap around and ran it backwards to get as much thread as i could on there. Then went in and cut the area down that didnt get threaded.

Did my first parting operation and failed to cath the piece so I had to dig it out of the bowels of the lathe. But you can see a side by side of the original on top and my replacement on bottom.

Still need to face it off and cut the slot for a screwdriver. But i think I'll cut the other first while I think about how to slot this. My first thought is to grind a HSS tool and turn it sideways to use the lathe crosslide as a tiny shaper. I only need to go maybe .050. Probably could use a cut off disk in the dremel but that feels hacky and doesnt really teach me anything. I really wish I had a milling machine right about now because I do have tiny end mills that would work for this. Open to suggestions.

 

[jmiller]

First one took about an hour. Second one took maybe 10-15 minutes. I wanted to show my parting setup here.


I know my lathe isn't the most rigid thing, but i think this is pretty low stickout. I drowned it in cutting fluid but there was quite a bit of rubbing/chattering sounds until i got to the last 25% of the cut, then it got nice and smooth for the remainder. The blade still feels sharp and the parted face actually looks decent. Is this to be expected for parting?

 

[jmiller]

I have to say this set up worked remarkably well! .002-.003 passes were nice and easy. All in all that took about 10 minutes to get to .050 depth. I had to do it twice because the tool was quite narrow and one pass wasnt wide enough for a mid sized screwdriver. I found the tool already ground in a lot of HSS bits I bought off ebay a long time ago. It was in the box labeled "Worthless Tooling I Will Probably Never Use And One Day Grind Into Something Useful". Low and behold it was the perfect tool for one of my first meaningful lathe projects. Heres the setup and finished piece.