Myford ML7 Resurrection - A New Summer Project

[SightlessSeer]

I came across a Kijiji ad for a "Myford ML7 Lathe for Parts" on Monday about an hour after the seller posted it. Looking through the pictures all of the major parts seemed to be there and it came with a whole bunch of other random stuff (some was related to the Myford but plenty was not). The guy wanted $300 CAD for all of it and he was only 30 mins away from me. It felt like stars were aligning to tell me that I need a second lathe in my life.

Spoiler: Kijiji Ad

By noon yesterday the seller had gotten back to me and confirmed that it was mine and after work I went with my brother to pick it up and we continued my habit of bringing lathes home in the trunk of a silver sedan.

While I could see a lot in the ad's pictures, It wasn't until I got home that I was able to take a decent inventory of all that I bought. On top of the mostly complete ML7, I got a 3 jaw chuck for the Myford, a 1/3 motor with pulley, a couple dead centers and a cheap live center, a bunch of assorted HSS blanks (quite a few of them are ~3/4", which I'm not sure what to do with), a bunch of misc. metal stock (mostly steal of unknown type), a decent looking little keyless jacob's chuck with a MT2 arbor, and what I'm 90% sure is a second but much cruder lathe. On this second "lathe" there was a 6" 4 jaw chuck with a 1 1/2 - 8 tpi thread that fits my Atlas lathe, which was a nice surprise! There are also a bunch of random gears that seem to have nothing to do with the ML7.

Spoiler: The Haul

A bit of a tangent, but the crude little lathe is marked on several of its parts exp27. I think I can very faintly make out a "CMA" marking on one of the castings, but that is literally all that I know about this thing. If anybody knows anything about it I would be interested to know more. Looking over the pictures from the ad now, I think there was another section of dovetail plate and another dovetail slide (cross slide maybe? or possibly an incomplete tool rest for wood turning?) for the crude lathe that I didn't actually end up getting with everything else, but I'm really not very concerned about it.

As for the ML7, here is what I know is missing.

• The gear on the back of the spindle to drive the change gears
• Probably several change gears (I have maybe 5 or 6)
• A bunch of random screws and fasteners
• The cross slide gib
• Belt covers (I can live without these or fabricate something if not)
• Change Gear cover (I would like to either find one of these or fabricate on if I decide to keep this lathe long term)
• Several oilers
• Spindle bearing oil cups
• Quite a few gib screws
• Bull gear (present, but missing one tooth)

In addition to the missing bits, just about every single part of this lathe has very obviously been taken apart and messed with. I haven't found a single nut, bolt, or screw on the whole machine that is actually tight. I'm also pretty sure that there are a couple of pins in the spindle missing. A major part of this project is going to be taking the whole lathe apart and putting it back together again.

I did a cursory inspection last night and so far I've concluded.

• The spindle doesn't have any noticeable play side to side, although there is probably 0.005" of end play, but I'm pretty sure that's adjustable and can be attributed to nothing being tightened down properly.
• The bed looks pretty decent and there aren't too many nicks and no big gouges in it or any obvious signs of wear. I'll have to look closer to confirm this.
• The cross slide is in a bit rough shape. It's pretty dinged up and there are two spots where the T-Slots, which tighten the compound slide have had broken out. The one part that I think is mechanically fine is the tailstock.
• The countershaft assembly seems completely fine except for a missing oiler

This should be a fun project for the summer and hopefully I can get it into some sort of decent mechanical condition in time for winter. Then I'll be able to play with a lathe inside instead of freezing in my unheated garage in -20° C.

 

[djberta]

Super cool find. Very interested to see your thread on the resto.

 

[Dan Dubeau]

Congrats on the haul. That was a great find.

 

[Tom O]

The 3/4 tooling can be used for parallels.

 

[SightlessSeer]

The 3/4 tooling can be used for parallels.

That's a really interesting idea. I definitely wouldn't have come up with that. They might be a bit big for milling setups on my lathe though. Maybe I'll eventually find a deal on a milling machine that I can't ignore. Might be more useful on that scale.

 

[jorogi]

Wow, I would have thought you would have dozens of " YOU SUCK"s by now.

 

[Tom Kitta]

Stuff other then the lathe looks like is worth $300.

• Several oilers
• Spindle bearing oil cups

I got these off aliexpress - you can get nice brass ones.

 

[SightlessSeer]

Stuff other then the lathe looks like is worth $300.

• Several oilers
• Spindle bearing oil cups

I got these off aliexpress - you can get nice brass ones.

I'm debating making the oil cups myself. It sounds like a fun project, but what gives me pause is that I'm not sure if can manage a sight glass for them that won't leak. I'll check out AliExpress though. If they're cheap enough I might just go for that

 

[djberta]

I'm debating making the oil cups myself. It sounds like a fun project, but what gives me pause is that I'm not sure if can manage a sight glass for them that won't leak. I'll check out AliExpress though. If they're cheap enough I might just go for that

I just watched a vid the other day where the guy makes these, he even cut the glass from I think was test tubes. I will have to find that video now. It was done by one of the English machinist channels.

Ok I have to make a note here, other day could mean last week or 2006, so I will have a good look.

 

[djberta]

I just watched a vid the other day where the guy makes these, he even cut the glass from I think was test tubes. I will have to find that video now. It was done by one of the English machinist channels.

Ok I have to make a note here, other day could mean last week or 2006, so I will have a good look.

So the one with the test tubes was Quins video where she made the oilers for here vertical engine build. The one I was thinking of was Steve Jordans video from like 7 years ago. I might put this on my list of "why not make one".

 

[SightlessSeer]

So update regarding the spindle/the need for oilers. Last night I pulled the spindle out to see what I would find and I was ... surprised

Spoiler: Spindle Pics

Both of the white metal plain bearings have been replaced. The rear one was replaced with some kind of sealed bearing and the front one with a bronze (I assume) sleeve. Honestly, whoever did the Bronze bearing didn't do a bad job. I don't notice any play between it and the shaft and it's a snug fit into the spindle casting and cap. What is ... interesting is that instead of turning a shoulder onto the bearing to butt against the casting and act as thrust surface like the original, whoever did this bodge cut the front of the old white metal bearing halves off and used them as a 2 piece spacer/thrust bearing for the spindle. The two pieces are free to spin independently of either the spindle shaft or the spindle casting and are held captive by the bearing cap on the smaller outer diameter of the spacer. I suppose this isn't the _worst_ solution I can imagine, but I definitely don't like it. The rear sealed spindle bearing setup is also a bit of a mess in its own way. Again, the bearing is a really nice fit on the spindle. No perceivable play between it and the spindle shaft and I can't feel any play between the outer race and the inner one either. The two issues I see here are that

1) The outer race is larger than the original rear bearing was. This means I can't secure it properly with the rear bearing cap (although thinking about it now, the issue might actually be that the bolts of the cap aren't inline with the bearing so the cap tilts as it tightens. I'll have to look again later to know for sure)
2) The threaded collar at the back of the spindle which is normally used to adjust the end play of the spindle has nothing that is can press against to take up the slack.

I'm going to have to think long and hard about what I want to do here. The impression that I've gotten from people around the internet is that split plain bearings like were originally there are matched to the shaft, so I don't think I can simply pick up a used or even new pair of bearings and call it a day. I would have to buy a new the spindle shaft to go with new bearings. On the other hand, the sealed bearing that I found on the shaft already has gotten the cogs turning in my head. Maybe I should replace the plain bearings with either a pair of tapered roller bearings and tension them with the collar at the rear of the spindle (similar to how the Atlas 10F's spindle is setup), or use angular contact ball bearings (I believe that Logans use this setup). If I go with either route maybe I can get sealed bearings and reduce the need for oiling/greasing them. That would be a nice quality of life improvement! To do this though I think I'd have to bore some grooves into the spindle casting for the new bearings. My atlas is a bigger lathe so should be able to line bore it, but I'm not sure if that's the route I want to go for yet.

What I'll probably do leave the spindle bearings for last and deal with this situation when/if I have the rest back in shape.

 

[SightlessSeer]

[...]
Maybe I should replace the plain bearings with either a pair of tapered roller bearings and tension them with the collar at the rear of the spindle (similar to how the Atlas 10F's spindle is setup), or use angular contact ball bearings (I believe that Logans use this setup). If I go with either route maybe I can get sealed bearings and reduce the need for oiling/greasing them. That would be a nice quality of life improvement! To do this though I think I'd have to bore some grooves into the spindle casting for the new bearings. My atlas is a bigger lathe so should be able to line bore it, but I'm not sure if that's the route I want to go for yet.
[...]

I actually found a thread where somebody did exactly this after a quick google.

 

[SightlessSeer]

Haven't made any dramatic progress since I last posted, but I have made 7 new 3/16" BSF gib screws. Of course the first step of this was grinding a 55° threading tool.

I got my process down to where I could single point one from start to finish in ~20 minutes, which I think is pretty decent. I ended up doing the turning facing and parting all using the threading tool and it worked well enough. I was using 3/16" stock held in a MT3 collet in the Atlas so there wasn't too much material to remove. I put a nice round on the ends of the screws with a file. Once they were parted off I cleaned up the head with the file before cutting the slot on the bandsaw. In an ideal world I think I would harden these, but I don't have a blowtorch or any other way to get them to temp, and I'm not sure what type of steel they are, so I'm probably not going to bother.

Spoiler: Gib Screws

The pictures up to this point are all of the first gib screw that I made. This one was a bit of a failure. While it fit fine in the 3/16" BSF nut that I was test fitting, it ended up too tight in the cross slide. I found that the nut from the half nut gib was a tighter fit, so I used that one as my reference going forward and that worked much better.

You'll notice that the screw at the bottom is one of the originals with the broken slot

Here you can see the new cross slide gib screws installed into the cross slide. Now I just need to finish the making the new gib ...

Overall, I made 7 screws, which took 9 attempts. The first one was too tight a fit and I took too deep a threading cut on the fourth attempt and snapped it off. Definitely would have been easier to buy these, but it was a fun little mini project.

Last Saturday, I bought a Hardinge UM Milling machine. Once I've made some basic stuff for it (like T-nuts and studs to mount the vice), I'm planning to machine the new gib as my first real project on it. As you can see in the last photo, I have a strip of cast iron roughed out already. I cut this out of a sacrificial scrap wood-lathe bed. It should be suitable enough for this.

 

[trlvn]

Great work. I don't think you really want to harden the screws. If hard, they would just chew up the gib faster.

Love the fishtail gauge--West Germany, eh?

Craig

 

[Dan Dubeau]

Nice job on the screws. Jealous of your recent Hardinge pick up. I've wanted one for a long time (along with an HLV-H). Looking forward to the pics of that .

 

[Susquatch]

Great work. I don't think you really want to harden the screws. If hard, they would just chew up the gib faster.

I've even seen where guys have used brass tipped Gibb screws. Not sure I support that, but I certainly agree with you and wouldn't harden them either. Screws are super easy to replace. Gib wedge plates are not.

 

[kevin.decelles]

Have your considered pouring new Babbitt bearings? I’d like to see pics of that!

 

[SightlessSeer]

Nice job on the screws. Jealous of your recent Hardinge pick up. I've wanted one for a long time (along with an HLV-H). Looking forward to the pics of that .

I'm not sure if I'll make a dedicated post about it or not, but here are a handful of photos that I've taken of it so far. If I do make a post I'll link it in this thread for you.

Spoiler: Off Topic Hardinge Posting

These are the pictures from the Ad. The machine was about 2:00 away from me in Montreal. I paid $3750 for it, which is more than I would have liked to pay for a milling machine, but it really is the perfect size for the space that I have and came freshly rebuilt and kitted out with a pair of VFDs and a DRO. There really isn't anything that I need to do to it other than wire in a longer cord for the VFDs (the one it came with is ~1.5 ft long). The machine is even wired for 110V 15A, which is perfect since my garage doesn't have 220V.

I pulled all 1000 lbs of the mill home behind my little Civic. While I will not be putting that much weight behind that car again (unless there's a particularly good deal on a shaper ), it handled it impressively well. Stopping distances were very noticeably longer and it struggled to maintain highway speed on hills unless I downshifted, but I took it slow and it turned out fine.

I managed to unload it by myself without any issues with the help of my newly purchased engine hoist, but the whole process took about 3 hours.

There was barely enough room to get the hoist through the garage door but we made it.

Once I had the hoist in the garage it was much faster. The smoother cement floor made it much easier to push the whole setup.

And here we have the mill in its new home. I have since wired a new outlet behind it and I still want to wire a new LED light overhead since that corner of the garage is pretty dark once the sun goes down. In the mean time, I'm using a block heater extension cord and keeping an eye on the current draw with the VFDs.

My first (and so far only) project was to make a nice chunky pair of nuts to hold the vice. I want to make some more T nuts and some strap or toe clamps before I'm ready to take a stab at milling the Myford gib. I think that's going to be the first non-tooling project.

Great work. I don't think you really want to harden the screws. If hard, they would just chew up the gib faster.

Love the fishtail gauge--West Germany, eh?

Craig

Good point on chewing up the gib. I was thinking about preventing the slot from getting bent or chewed up instead of the hardening the tip, but I doubt that I could get one without the other on such a small part. I also learned today from the Hobby Machinist version of this thread that the gib screws on a Myford are actually 2BA, not 3/16 BSF ... Main differences are 49.5° thread profile and 31.4 TPI instead of 32. The ones I made fit well enough that I'm not going to remake them (I actually can't cut 31.4 TPI on my Atlas, so it's a bit of a moot point regardless), but if I order anything from Myford then I'll make sure to pick up a set of these.

Have your considered pouring new Babbitt bearings? I’d like to see pics of that!

I haven't seriously no. I really don't know anything about the process and I don't know where I would source the Babbitt. I'm not sure if the remains that I have of the original front bearing is Babbitt or not, but if it is I definitely don't have enough of it to recast the bearings. I would think that you'd still have to bore them out? At that point I think I'd just put shoulders into the headstock casting for Timkin or angular contact bearings.

 

[Tom O]

Keith Rucker has some good vids on pouring Babbit, they are poured with the shaft in place usually in two halves and scrapped to get the right clearances. There are different versions of Babbitt depending on rpm and temperature.

 

[Dan Dubeau]

Thanks for the pics and story of the journey to get it home. I've wanted one of those for a long time, that looks like a great fit for your shop. Congrats.