Fixing Cross Slide Backlash on my South Bend 11 

Thanks for coming

Great to hear! Thanks

Thanks for watching!

Very true! Thanks Matty!

Very welcome Thanks for the comment.

Thank you sir! This has been bugging me for a while. I can deal with .005 or even .010" but .040 was way too much.

Interesting... thanks

Nice work! You almost have to have at least .001!

I agree, Thanks!

Thanks!

Thanks... I definitely should have used oil!

Thanks!

Thanks, I'm glad it looks stock, I didn't milling my classic lathe but it added to it's function.

Thanks! It went much smoother than I expected.

Exactly! Thanks!

It is odd. South Bend changed there design after they made mine,

Thanks, yeah, it came together much better than expected. I figured the lead screw was worn.

Thanks. I actually made an extension and made a larger dial. I need to put a self locking nut on the handle.

I probably missed the video, and don't know anything about SB to have recognized a

Go for it

Thanks Richard!

I think so too. Thanks!

Thanks Jim

I'm not sure that was a positive of negative comment. I'm kidding, Thanks!

@@WinkysWorkshop LOL. I didn't think of it that way. I wasn't bored, I had just eat and you know a person can get a little sleepy after a big meal.... Hopefully they gave you two views !!!

@@dannywilsher4165 No worries... just messing with you.

Thank you!

Thank you so much! Somebody else said the same about the cutting edge.

Thanks for watching!

Thanks... I got lucky, everything just worked!

Thank you !

Your welcome, Thanks for watching!

I don't know, it looked original but you are right... a silly thing to overlook. Thanks.

Thanks for the visit

Glad you enjoyed it

Thanks Ray, you're too kind!

Thank you sir

My pleasure

Thanks !

Thanks James~!

Yes the tap handle is simple and super nice. Thank!

True, thanks

Thanks... I'll admit, it went smoother than expected.

Thanks

Thank You!

Impressive! I'm glad I have two lathes, they have been handy on several occasions. I originally planned to sell one but can't bring myself to do it. The SB is more solid than by Logan but the Logan cuts slightly smoother and the carriage controls are easier to use.

@@WinkysWorkshop Decisions, decisions eh, LOL.

@@TomokosEnterprize The Logan is gone and I miss it now.

@@WinkysWorkshop I bet. We sure love our old iron eh.

You can avoid brass grabbing on a drill and pulling it into the cut by grinding a negative rake to the two cutting edges. That trick also works when drilling plastic.

Hello Danny! thanks for watching!

I like this lathe, was the bolt holding your nut sticking up ?

@@WinkysWorkshop Yes, it does have the bolt that restricts the rotation of the compound.

@@RAYAR54 Thanks, the only reason I asked is that after posting this video I had several tell me that mine was not original. I suspected it was and you just confirmed my suspicion.

Yay! Thank you!

That's a good idea. Fortunately the south bend cross slide cover comes off easy. I keep it well oiled. Thanks for the idea!

Thanks Danny!

Thanks!

Thanks

Yeah, I need to drill the hole for oil. I like the nylon idea but this nut is fairly thin, I'd be worried about strength.

@@WinkysWorkshop its not as strong as brass in compression but it is actually pretty rigid stuff. You should order a piece of it and check it out. I use it for lots of stuff I even put a piece of it on the edge of my old snow shovel for a wear edge.

@@ALSomthin I may try it but probably not for this lathe.

I think my south bend if more solid but the logan cuts smoother. I like them both.

Wow... Thanks!

Thanks!

Thank you sir

Mine was cast also... I think brass wears about the same or a little better and it is easy to work with

Thanks 👍 I found out later that south bends changed there design later and made it the same as mine. I basically copied there design.

Thanks, Oddly enough, this modification made my lathe like most other South Bend lathes. Apparently this bolt was only used on early South Bend 11" lathes.

I noticed that in some pictures - Thanks for the info.

Same with my 1939 SB 11"×4'.

Interesting, I never heard this about the acme taps but it might be true. I've had good luck but it takes a lot of torque.

@@WinkysWorkshop Funny, I was just watching, yet another Cross feed video and guess what he says? ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-HbUzO_Ecxic.html

Thank you! Cheers!

Thanks you sir!

Thanks

Brass is easier to machine and better than steel for wear plus it's fairly strong. I'm sure some sort of bonze would be better but I'm not sure what type.

@@WinkysWorkshop When I was making silver chopsticks(.925 Sterling)(I have a couple video's on them) It was necessary to toughen up pure silver so the sticks wouldn't bend out of shape when being used. I was originally using copper as the alloy but was having some difficulty with getting the metals mixed so no copper would show. A good friend suggested I use zinc (another soft metal) so I went primarily with zinc and a touch of copper and brass. I had to pour the mix a total of 5 times to get it properly mixed. I am still amazed at how tough the mix was/is. Effort is needed to cut the 1/4 x 3/16 in sticks with a 18 in pair of bolt cutters that if the mix was pure silver a 12 in bolt cutter would easily snip through them. Perhaps a copper/zinc alloy would work for you in this case. It would be easy enough to pour a block of it. Possibly a new project for you when you have nothing else to do, LOL. In the spring I can put a pour of it together for you for fun. It would be great to do a small project together. I would just need an approx. weight and rough casting sizes. I would think an 1/8" on all sides would give you a nice clean piece when finished. I still can't get over how 2 or 3 soft metals will make a really hard one. A while back a pourer called "Backyard Bullion" from England and I did a trade. He did a really nice video on the sticks.

@@TomokosEnterprize - Thanks for the offer. I might take you up on something like that in the future but I'm not sure I want to make the nut again seeing as how it works quite well. I think it will likely last too. Brass might not be idea but compared to steel on steel it's much better... likely better that steel on cast iron too... which is what the original was.

Thats a cool idea!

Thanks for the visit

Thanks 👍Yeah, Old time sounding, I like it too!

Thanks!

Same design as the adjustable leadscrew nut on my Harrison. The split line is about 1/3rd from the back side with 2 small Allen screws to do the adjusting of backlash with.

My nut was cast iron. It probably would not flex at all. My mill is made like what you describe.

Thanks Tom!

Thank you! Cheers!

Thanks

Thanks!

Thanks Joel!

Thanks!

I like the 11 inch lathe. Yes I was looking at a lot of pictures and most are made different. Mines a 1931.

@@WinkysWorkshop I could see that yours was older than mine from the apron controls, but many things do look identical. You wouldn't have an extra follower rest you're not using, would you? I have a steady rest, but no follower. Also, I am curious to see if your spindle threads are the same size as mine. Mine are 1 5/8 X 8 tpi.

@@cleophusA - Yes that's the size of my spindle too. I don't have a follow rest of steady rest although I plan on making both at some point.

@@WinkysWorkshop Oh, good! I'll look forward to seeing that. There's really only a couple of things I would like to get for my lathe that I don't have yet. One, as I said is a follower rest, and the other is a 3 or 4 jaw Buck or Bernard scrolling chuck. Do you have a supplier for cast iron backing plate blanks?

@@cleophusA - I prefer steel and make my own back plates. It's a big job but still worth while.

Your welcome, thanks for watching!

Thanks

I'm pleased with the results for sure! Thanks!

This old Tony did a video where he tapped inside acme threads. The tap is way easier and only cost me $22 on ebay. Thanks!

Thanks, yes and that is a good thing. I hated to drill the casting but the original design was limiting.

Thanks

Cool - Thanks!

Thanks!

Glad you like the video. Thanks

Well you can cut thread with the compound to the left front but the chuck tends to get in the way. It looks like South bend corrected this problem after my lathe. Mine if a 31 model and a guy commented that is 1937 lathe was not made like mind. Thanks for the comment Andy.

Many many thanks

Yeah... I like to make sure a modification is worthwhile before I alter a machine but if it's worthwhile I do it. Thanks for the compliment!

Thanks!

I've heard that before... thanks!

I was just going to mention the grub/pinch screw tightened onto the leadnut extension boss. It is a good method of securing the lead nut.

Glad to hear it!

I had one on the left side of the camera. It was very HOT!

"Lions and tigers and bears? Oh my!" Hahaha... sounds very interesting actually. Morning coffee with the view might be nice. Thanks for the offer and I watch for the candle. ;o)

Thanks Paul, nah, the regular large screw driver works fine.

I thought about that too but I've been giving the lead screw a shot of oil. I'm sure it is adequate. Thanks

It was a 1/2"-10 LH Acme tap. I got it on ebay for about $24. I still have some backlash but it's much better.

Thank you for the information. I measured mine, it is a 7/16"-10 ACME LH thread. After watching your video, I disassembled mine and found a couple loose bolts that had contributed to the issue. I cleaned and reassembled the unit. I was surprised and glad that the backlash is much, much better now. .007” vs .018” of backlash. I wish I can completely eliminate it. What do you think about making an anti-backlash nut by using maybe one third of the old cross slide nut (I call it the tension nut) and bolting it to the new one with a spring in between them? In my case I would use a 1/2" dia X 3/4" spring outside the lead screw and two #10 bolts (in the area above it) to bolt the tension nut to the cross slide feed nut

@@TinhNguyen-mb7gx - Honestly .007 is fantastic. Without ball screws and some kind of thrust bearing at the dial you can't expect much better than that. I think a anti-backlash nut of some type would help but I'm guessing you will always have .004" or more. I'm not sure it is worth the effort. I've seen people modify the nut by cutting part way through (as if you were separating the nut it into two nuts) and adding a small set screw that separates them at the cut. The uncut section flexes a little and removes the backlash when you tighten the set screw.

Thanks for the input. I'm not sure there is enough room to do this although I might try if the nut starts to wear. Currently the amount of backlash is very slight and even slightly tight on one end of the travel. Also, when I ran the tap through the nut again it opened a small hole between the mounting bolt threads and the acme. I think I might drill a small oil port in the mounting bolt.

@@WinkysWorkshop if you drill a hole thru the mounting bolt.. put a piece of felt at the bottom of the 3/8-16 hole in the brass part..

@@waynep343 - Sounds like a plan.

Several others have said the same about bronze and I'm sure it would be better. I'm guessing brass will wear better than the original cast iron and it lasted 90 years. Brass is used in car water pumps and boat propeller shafts because it resists corrosion better than bronze so I'm sure it will be adequate.

Maybe if I need to. Right now it works great. I'll keep the threads lubricated, the cover just drops on. Thanks