# head power down-feed not working



## quickcut (Sep 5, 2014)

Good day all

My bridgeport clone power down-feed has stopped working. Any pointers where to start before I start stripping. many thanks


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## Rbeckett (Sep 5, 2014)

The planetary gears seem to be the weak link in all of them, so pop off the end cover and have alook at the gears inside.  you should find the problem pretty quickly if the motor is running and nothing is moving.  If the motor isn't turning then you will have to do some different trouble shooting to discover what is goin on with that.  It could be bound up because of gear chips or something else may be causing the issue.
Hope this helps.


Bob


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## JimDawson (Sep 5, 2014)

That is a pretty complex system.  Is there anything turning, like the little knob in the center of the hand wheel hub?  There are 5 separate items that have to engage in order for it to work.  One is the gear engages that the main drive from the spindle worm (lever, upper right hand side), the next one is the speed selector gears, the next is the forward/reverse knob, next is the slip clutch on the left side of the head, and the last is the dogs on the quill shaft.

Each of these item has a key that drives it.  If any of the keys shear, it won't work.  Many times it is as simple as adjusting the clutch, but you will know if it is slipping, it makes a lot of noise.

It would be helpful if you can tell us what happened just before it quit working.  Any noises?  If you engage the feed, can you move the quill lever? (you should not be able to with out a lot of force on the handle).

You just need to go through a logical trouble shooting progression to find the area of failure.  We can help you through that if you like.


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## quickcut (Sep 6, 2014)

Many thanks for the kick-start. It would appear that the gears and downfeed selector are all working. Next I removed the clutch cover and found that that ratchet shaft is not turning. The little shaft in front of the head is also not turning. Thanks in  advance.


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## Rick Leslie (Sep 6, 2014)

This is a very timely thread. Not to highjack, but mine has the same problem. Only everything seems to be turning on mine and the manual downfeed lever will not move when the clutch is engaged. No noise from the clutch either. Everything seems to work fine until I actually try to power downfeed, then it just goes through the motions or kicks out. 

I'm very interested to see what you find with yours.


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## JimDawson (Sep 6, 2014)

quickcut said:


> Many thanks for the kick-start. It would appear that the gears and downfeed selector are all working. Next I removed the clutch cover and found that that ratchet shaft is not turning. The little shaft in front of the head is also not turning. Thanks in  advance.



I would start by removing the feed engage lever, upper right had side of the head.  Make sure that the gear that engages the quill drive is not worn out and that the lever moves the gear into position.  Here is a good parts list with pretty good drawings.  This may not be exactly your machine, but I think most of the parts are close enough for trouble shooting.  http://www.hhrobertsmachinery.com/S...arts-Lists/Topwell/Topwell-3VK-parts-only.pdf

The next area to look in is the speed selector, once that cover is removed, you can see a lot of the parts to see what is turning.  I have never tried to run anything with that cover off, but you could turn the spindle by hand to see what is moving.

As you can see, there are a lot of little parts (#1-#126) in there so it is just a matter of finding the failure.



Rick Leslie said:


> This is a very timely thread. Not to highjack, but mine has the same problem. Only everything seems to be turning on mine and the manual downfeed lever will not move when the clutch is engaged. No noise from the clutch either. Everything seems to work fine until I actually try to power downfeed, then it just goes through the motions or kicks out.
> 
> I'm very interested to see what you find with yours.



If it kicks out then that would normally mean the the engage pin is out of adjustment.  Take a look at parts 92-99 from the above drawing.  The adjustment screw is #118 on the drawing and is accessed from below the flange of the quill stop.  Make sure that all of the moving parts in that area are free to move.


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## quickcut (Sep 7, 2014)

Once again thanks for the pointers . It would appear that the shaft that connects the hand wheel in front had a problem. To activate the down feed this shaft needs to be pushed in in my machine. When pushed in it did not activate. I stripped it out and instead of a ground pin the used a split roll pin.Now replaced with a solid pin and everything is working, just a bit tight when pushing the shaft in to engage the feed. Thanks again.


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## JimDawson (Sep 7, 2014)

quickcut said:


> Once again thanks for the pointers . It would appear that the shaft that connects the hand wheel in front had a problem. To activate the down feed this shaft needs to be pushed in in my machine. When pushed in it did not activate. I stripped it out and instead of a ground pin the used a split roll pin.Now replaced with a solid pin and everything is working, just a bit tight when pushing the shaft in to engage the feed. Thanks again.




I'm always happy to help out.  Glad to hear you have it working again.


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## Rick Leslie (Sep 7, 2014)

Thank you for the pdf. Will check that today (I hope).


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## workhardening (Sep 17, 2014)

I'm right at the same point in rebuilding the power down feed on a Series 1 J head that I'm repairing.  Bridgeport calls out a 3/32" x 3/4" roll pin for this part. (This is the pin that goes through the feed reverse clutch and the reverse clutch rod.)  Though a solid dowel pin would probably work just as good, and last a lot longer, it might be beneficial to make sure that the dowel pin will pass through the hole in the reverse clutch rod easily.  If it is a press fit, it might expand the end of the reverse clutch rod slightly, and this could be what is causing it to move in and out with resistance.


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## jmarkwolf (Sep 25, 2014)

I had the same problem when resurrecting my old Bridgeport.

As I recall. a pin through the handwheel shaft had broken. 

I bought a new replacement (roll pin) but it was too big or too long or something. 

I ended turning a solid pin from a nail, as suggested on this or other forums. 

Works fine now.


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## workhardening (Sep 28, 2014)

I rebuilt the feed worm shaft assembly last night, and ran into a problem.  I had ordered a new worm shaft and clutch rod, as the old ones were too badly damaged to reuse.  Once I got the assembly together, the clutch rod was very tight.  I could just barely get it to move in and out, and it was requiring too much force to do this.  At first I thought that I might have bent the roll pin when I reinserted it, so I drifted it out, and replaced it with a new one.  Once it was back together, I still had the same problem.  I decided to take the assembly back apart, and find out whats going on.  When I looked at the clutch rod, I found out that the hole for the roll pin in new clutch rod was smaller than the roll pin hole in the original Bridgeport part.  I checked to find out what diameter of index drill bit would pass through the hole on the OEM part.  Then I drilled out the hole on the new clutch rod with a #37 index drill.  After I did this, the feed worm shaft assembly went right together and works smoothly.  The roll pin needs to be a close fit to the hole in the feed reverse clutch, but it only needs to pass through the clutch rod.  I hope this information helps.


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