14x40 lathe power feed improvement

I didn't elaborate on this aspect much, but maybe worth mentioning with a pic. Yet another potential fitting tweak you might encounter. The brass gear that engages the steel worm gear is mounted on a shaft with a key. The steel worm gear drives the brass gear which drives the internal carriage gear train to traverse the carriage. That's the power feed mode.

The brass gear can only go on one way. It has a depression on the outboard side for a washer & cap screw. But what I had not appreciated until I chased down my particular misalignment issue step by step is that the brass gear can actually be set improperly. I assumed it should butt up against the shaft shoulder (and I suspect that's how its supposed to be). But for whatever reason, probably related to my apron not being positioned correctly on the carriage top (but nothing I can do about it) its possible to have a perfectly concentric PF rod running within correctly set up bushing block, but if this brass gear is off center even a slight amount, that will make for binding. Because the gear has kind of a saddle profile, any in/out deviation really aggravates this misalignment. Hope this makes sense. Anyway, that's why I ended up having to make a brass shim washer between the apron casting & brass gear to establish this distance because if I tightened the gear end cap fully, the gear slid it down the key & was out of alignment.

Now whether I'm correcting 'factory' issues or this is an inherent design thing, I can only guess.

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I was looking at my today and oiled the devil out of it and noticed that there's 'rub' marks on the PF shaft in the sweet spot since I really started using the lathe.
I'm in denial/ignore mode now. Have to cross my fingers and get through the next few weeks. Just picked up some more side-work this evening.
I'm going to have to go through your posts in detail and figure it out from there. And figure out when to fix the Low gear klunking.
 
Its hard to speculate. From what I've now seen, I think there was a significant amount of final hand fitting work when it comes to these machines, at least this particular model/era. Don't get me wrong, its great value & quite accurate. But some corners cut that could have made a good machine much better.

Here are some interesting pics I forgot to post but maybe another clue. See how it has no wear on the apron side of hole, you can still see original drilling & even overspray paint. But its rubbed shiny on outboard side of hole? That tells the same story of how my blocks wanted to be shimmed to run concentric once the straight rod was installed as the datum. The ‘extra’ shim thickness came about because I mimicked the hole center dimensions of the original C-bracket bore & it was wrong to begin with. The question is when did this occur, slowly over time or aggravated by when the gear issue occurred.

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I got lucky & Modern Tool in Calgary was able to source me some parts from factory in Taiwan including the springs. I don't have other lathe brands to compare but my hunch is they may be generically similar to others if that helps.
 
cd_edwards said:
knew I'd seen some others pics of this. . Where did you find the new springs? seems I need one to replace the roll pin someone installed in place of one of the springs..
Click to expand...
Mine were made of rather heavy wire, diameter was a tad smaller than 1/4" about 3/4" long. Rather crudely made. Ends were just cutoff, not ground.
I did have a hunk of the same type in my parts drawer, but didn't bother to make proper new ones.
I've got pictures somewhere - but of course can't find them at the moment...

My gears looked decent during the tear down to fix the half-nut a few ago.
Wish I had remembered this thread so that I could have modded it while I had it tore down.
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