To tear down or not to tear down...

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Hukshawn

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So, many of you know I just got a b-port clone j-head mill.
The quill power feed doesn't work. Nothing binds or grinds, all levers seem to work, but something isn't turning somewhere.
My experience with mechanics/machinery is decent to intermediate, my experience with a j-head is about 0.1 as I had to have Mr Pete tell me what all the levers do...
I'm terrified of breaking something by tearing it down to fix it. I'm so happy to have a full size mill, I really need to not wreck. Everything else seems to work fine.
 
First thing to do would be to get familiar with the power feed innards before you try to take it apart; get the drawings and parts list and study them.
Also see if there are any special wrenches or tools you might need. Then go for it.
Forewarned is forearmed I always say.
Mark S.
 
Only you know your own ability on dismantling and reassembling machines. Do you know how to handle tapered pins, springs, snap rings, thust bearings, etc.
Are you confident on documenting the disassembly sufficient enough to get it back together without having extra parts left over?
If so, than go for it, and you’ll have lots of support from folks here and on youtube. If you’re not sure perhaps better to follow your gut and find a friend that can help you.
I’ve seen lots of dismantled machines out there where someone got over their head.
 
I started taking the table apart cause thats easy. Its cleaning up quite nice
It's just all the springmathings and parts in the head. I was watching Keith Fenner do his current Bridgeport referb, and the number of items he had to remove just to remove one certain device. That's the part that intimidates me, I suppose.
I'm trying to obtain an exploded views manual, but finding info about these Firsts is rather difficult. The long chang company doesn't return emails, it seems. I realise this is a Bridgeport clone, but I've read before that there are some differences.

I've already encountered bearings in the x-handles that need replacing. So, I'm not optimistic the quill feed is something simple.
 
You only learn by going in to uncharted territory, if there is no grinding or other mechanical violence, it sounds like a shear key or pin has failed.get the tools out!
 
The first thing I would do is get a hold of a manual for the Series I machines and study it. There are several online sources for free PDF versions. Then contact H&W Machine Repair and Rebuilding. Their website is MachineryDepot.com:

http://www.machinerypartsdepot.com/

They are experts on Bridgeport machines and very easy to talk to. Over the years I've purchased several parts from them and have gotten excellent advise on how to install them. The problem you describe could be very simple to correct. There is a small part which I believe is called a feed trip lever that often gets broken . It's easy to replace and only costs about $23.00. Be sure to get directions on how to install it. Many times it gets installed incorrectly and breaks

It was broken on my machine when I got it from a local high school. It took less than half an hour to replace, and now the quill feed works flawlessly.
 
Digital pics are your friend. Photo document every step of your disassembly, and clean and lay out your parts in the order they go back in with notes as to which side goes in which direction. If your unsure how a certain part is held on check here or You-tube. Every time you work on something it gets a little easier. After 50 some years of it, I'm almost competent. :big grin: Mike
 
Many BP mills have a quill stop mechanism, this will likely be the first thing that fails, determine whether or not this has become a permanent condition.
 
I think the keyway option may be the culprit. When I engage the worm I can hear and feel something engage, but the hand wheel collar doesnt turn, and when I crank the fine feed, it doesn't turn anything. But you can feel gears meshing.

I will get there. Right now I'm tearing down the table and lower end. Cleaned out the pump, the sump is FULLLLLL of chips... The one shot, the flood nosle, various other lower end/table stuff.
One of the x bearings are shot, I have a local industrial supply shop ordering me parts.

When I get to the head I'm sure I'll be glued here.
 
Since my mill is a bridgeport clone, how would I determine what series or model it is a clone of?
 
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