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New 9A Cross Feed Help

Alex D

Plastic
Joined
Sep 11, 2019
Hello, I'm new here and a hobby woodworker slowly getting into hobby metalworking. I picked up a nice enough 9A and I'm in the process of getting it up and running.

The main issues I'm experiencing relate to the cross slide and I'm hoping to get a bit of advice from this well-versed group.

1) When up and running, the power cross-feed seems to run backwards (from in to out). That seems counter-intuitive considering what (little) I know about facing operations. Am I supposed to use the reversing gears for the cross-feed, then switch back for longitudinal feed or is there something wrong with the lathe?

2) When turning the cross slide by hand, it starts to bind up after a few turns. I replaced the worn-out nut and it still binds. I removed the nut entirely and it still binds which tells me there is something up with the cross-screw. After removing the compound, it's clear there is a bend in the acme portion of the screw, but since it is still binding without the nut, I'm thinking there must be something boogered up in the geared end of the screw or possibly the bushing.

3) How do I get the screw out? I have the handle and dials off, but it doesn't slide out. It moves in about 3/4" or so, then gets stuck. I don't want to break anything so I'm not using any persuasion on the handle end. I think I probably need to get the bushing out and then figure out how to attack getting the screw out, but my bushing doesn't have any hole for a pin wrench. From what I've read here it sounds like the best method is either a strap wrench or soft jaws and vice grips, but I just want to confirm that. I don't see any setscrews anywhere else on my saddle, just an oil hole on top (and I checked, there is no screw in that hole).

4) Finally, once I get this thing out, is there anyone that repairs these? I've seen repair kits listed on ebay, but I am jut beginning and not sure that trying to remake the screw on my only lathe is a good first project...

Thank you!
Alex
 
1) the facing and longitudinal feed on southbends do that. As you say, you need to change the tumbler reversing gears to go from feed right-to-left and change to facing out-to-in. Do NOT change them when the spindle is in motion. This peculiarity happens because of the apron design in the SB lathes.

2) the screw, bushing and handle can come out by removing the entire assembly. Unscrew the bushing from the front of the apron and you can get the thing on the bench and find out where the binding is happening.
Some of those lathes have a hex on the bushing, some have a pin wrench hole. Or, wrap some copper around it and use vise-grips. Some machines come with vise-grip marks on the bushings from the 'factory...'
 
If you are facing things like rifle barrels and others with a precise bore, you want to cut from in to out. This stops any burr being formed in the edge of the bore.
 
Thank you both. I am going to head to the shop later today armed with a strap wrench, soft jaws and vice grips. Hopefully something will give and I can get the bushing out. It's a bit odd that it doesn't have flats or a pin hole, but maybe it's a shop-made part, or maybe it was made on a Friday afternoon!

I'll update this with pics after I (hopefully) get the bushing out.

Thanks,
Alex
 
If you can not remove the bushing/nut from the cross slide wrap it with a piece of leather & then put some pliers on it .That was te only stuck thread on my 9A when I striped , painted & replaced
my 9A when I first bought it . It was stuck real good ! If I was smart I probably would put some nosieze on it during reassembly .
animal
 
A couple things things from another 9 Junior, junior...
Is this an A with a B apron power cross feed.
Have you had the apron off and cleaned it up so you know it's not the apron causing the cross screw binding?
Perhaps lowering the apron just enough to unmesh the gears may help in your binding search?
I re-watched a video just now to help me. He loosened the apron screws just a bit to lower that gear, removed and reassembled the cross screw. He upgraded his C to a B.
mrpete #817 on the youtubes. I have a model C (not a powered cross feed and individual change gears) so I really don't know but we wish to help.
I hope you get it sorted and I'd like pics.
 
Drill the spanner hole 3/16 dia. 5/32 deep, 3/8 to center from end of bushing.
Heat the saddle around the mount bushing with a heat gun, not a torch, with a cold wet rag on the mount bushing. Heat it up, let it air cool, heat it up, let it air cool, heat it up let it air cool. 3 times or so. Thermal expansion of dissimilar metals should help it break free, then try a spanner tool.
Steve
 
Thanks everyone. I ended up using the aluminum shims and vice-grips and the bushing came out easy-peasy.

With it out, I can't see anything obvious that would be causing the binding. It looks like the there is a tiny bit of concentric marking on the portion between the busing and gear, but it has a spiral shape and I'm thinking that is just the shaft gently rubbing the threads inside the casting. It is uniform around the whole shaft which makes me think it isn't likely to be the cause.

Unless that could somehow be causing the binding, it seems like Duey may be on to something regarding the apron. I ran out of time today, but if I have a moment tomorrow I will try to lower the apron to get the gear out of the equation and see what happens.

And I will definitely drill out a pin spanner hole before I put it all back together to make it easier to remove next time.

Thanks!
Alex
 
Late to the party but here's what I found on mine a while back. The acme screw nut is twisted a bit causing your jamming up.
Loosen the nut up, and back the slide till it binds then loosen the gib screws a bunch. Knock the slide sideways then tighten the gib. See if your binding cleared up. If not, repeat and knock it the other way. Tighten the nut wedge screw when you have it right.

You say you took the nut out and it still binds. The slide? That can only be in the slide and or the gib. Clean it all out and reassemble. Gib in correctly?

edit:
With the brass acme nut out or the whole slide off the screw binds after a couple turns.. Then it's the gear train for the auto feed. If it was in the screw or the holder with the dial it would bind in one spot every turn. In that case go into the apron for the problem such as chips binding something up.
 
Last edited:
Ok, finally got back into the shop today. I pulled the cross slide off and sure enough, the cross slide gear in the apron was binding every 4th or so turn.

I pulled the whole apron off and turned the gear a few times looking for the problem, then it just stopped binding. Hmm, there was one chip in the apron, maybe that was it?

Reinstalled it all and sure enough it started binding again.

Pulled it apart and same thing happened, it was binding and then stopped almost immediately. That's when I decided to try and pull the shaft to see if there was something going on there. As I was tapping it out, the gear started binding again. Tap it back in, and the binding stopped. I tapped the shaft back and forth until I found the sweetspot where the gear didn't rub on anything in the apron, and also didn't bind. Fingers' crossed, I reassembled everything and it still isn't binding.

It seems like the shaft was tapped in too tight allowing the gear to bind against the apron casting. Now, I fully agree that doesn't seem to make a ton of sense. Why wouldn't it bind every rotation? I have no idea and maybe it isn't a permanent fix, but at least I seem to have narrowed down where the problem is. I'll use it for a bit and see if it comes back.

In the meantime, the brass shoes that belong under the dial setscrews are gone. Can I just replace them with a small piece of brass rod that fits in the setscrew hole?

Also, I found the bend in the acme cross thread. I have a decent sized arbor press, is there any reason I can't use some v blocks and gently try to coax the thread straight again, or is heat needed?

Thanks!
Alex
 
I have straightened several shafts that way, I usually set up a dial indicator that show how far past center I bent it then slowly keep increasing the overdrive until it is bounces back to straight. Its easy to go too far. If the arbor press is not too big you may be able to get a feel for the force.
Brass rod or even solid copper wire seems to work for the dial set screws.
 
I have straightened several shafts that way, I usually set up a dial indicator that show how far past center I bent it then slowly keep increasing the overdrive until it is bounces back to straight. Its easy to go too far. If the arbor press is not too big you may be able to get a feel for the force.
Brass rod or even solid copper wire seems to work for the dial set screws.

Thank you! I'll give it a try with the press tomorrow. Thanks for the tip on the copper wire. I have a good variety of sizes lying around so I should be able to find the right size.

Thanks again,
Alex
 
You can use a small fishing weight or a piece of soldier to replace the missing brass on the dial screw .
animal
 
I finally turned something! Nothing fancy, but I was to make a mandrel to install the gits oilers that were missing on the countershaft. Very basic, but fun and rewarding.

Surface finish was crap and I'm pretty sure I was using the wrong tool, but I'll get there.

I seem to have resolved the cross-slide binding, but it definitely takes some effort to crank the handle when under load. I expect a lot of that has to do with user error and tool position, but that will come with experience.

The main question I have (for now) is how to shim the cross-slide screw. I have about 1/16" of end play. I have seen many posts recommending shimming, but where does the shim go? Between the bushing and the casting? Between the bushing and the dial? Or between the handle and the dial? I tried the second and third options and the smoothest seemed to be when I shimmed between the handle and the dial and then didn't crank down on the retaining nut. When I shimmed between the dial and bushing things got very tight no matter how loose the gibs were set.

Thanks!
Alex
 
You need to remove the leadscrew, bushing and dial as an assembly. Take it apart on the bench to see exactly where the wear is. The end-play you see is the result of wear. The answer you will probably get is "everywhere." The bushing will be worn on both ends so it wil be short. The boss on the leadscrew that bears on the backside of the bushing, will be worn thin. And the dial will be worn thin.

Getting it all tight again means putting a shim in there someplace, often between the backside of the bushing and that boss on the leadscrew. The wear will have the parts worn with non-flat, there will be concenteric ridges on everything. If you face the parts so they are flat again, you'll increase the lash so make the shim after all that's done.

Another way is to *shorten* the parts that fit inside the bushing. The thinner part of the leadscrew that goes through the dial and bushing has its 'length' defined as the distance between the outer end of that boss, and the face of the thinner part that the round nut bears on (nut holds the handle on, has that cylindrical dutchman key in there). You can face that shaft shorter but at some point you will run out of room to extend the threads to put the nut on.

One way is to cut the end of that shaft off, silver solder on new material, and then re-fabricate the end so the face is in the correct (ie shorter) location.
 
You need to remove the leadscrew, bushing and dial as an assembly. Take it apart on the bench to see exactly where the wear is. The end-play you see is the result of wear. The answer you will probably get is "everywhere." The bushing will be worn on both ends so it wil be short. The boss on the leadscrew that bears on the backside of the bushing, will be worn thin. And the dial will be worn thin.

Getting it all tight again means putting a shim in there someplace, often between the backside of the bushing and that boss on the leadscrew. The wear will have the parts worn with non-flat, there will be concenteric ridges on everything. If you face the parts so they are flat again, you'll increase the lash so make the shim after all that's done.

Another way is to *shorten* the parts that fit inside the bushing. The thinner part of the leadscrew that goes through the dial and bushing has its 'length' defined as the distance between the outer end of that boss, and the face of the thinner part that the round nut bears on (nut holds the handle on, has that cylindrical dutchman key in there). You can face that shaft shorter but at some point you will run out of room to extend the threads to put the nut on.

One way is to cut the end of that shaft off, silver solder on new material, and then re-fabricate the end so the face is in the correct (ie shorter) location.
Jim,

Thank you so much for the very detailed and helpful response. I'll pull everything this weekend and start looking at the best option for taking up the space. Right now I have a shim between the handle and the back of the dial. I think that is sort of an ugly version of the second option?

Anyway, I'll report back. Having lots of fun working on this great machine.

Cheers,
Alex
 
It's a bit fussy but these repond well to TLC. The lead screw is probably a bit worn and you could take it to the next level by retrofitting a section of new acme lead screw. You can lock the cross-slide with the gib screws and turn the compound to point directly across the bed, and use the lathe to repair itself. It's been done.
 








 
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