Mounting new LMS bench lathe

I'm about to order a tabletop mill and was thinking of putting it on the Sams tool chests, small version of what Falcon67 used. How did everyone level the machine?
 
I leveled the tool box with a carpenters level, then leveled the aluminum plates in X and Y relational to each other using a digital level. The trick here is to have the mounting plates at the same height and on the same plane so as not to induce uneven loading into the lathe bed (flex). I used shim stock between the plates (the bigger one on the 3/4" plywood to provide a stable reference, the other on top of that).

I also didn't cinch the mounting bolts, as I just want them to induce unwanted stresses in the lathe. I just want them to keep the lathe from moving in the horizontal.

No problems so far, and the machine is way more accurate than I am.

The mill is even less critical than a lathe. I just leveled the top of the tool box with my digital level. Works great.

Bill
 
My Logan came bolted to a substantial 12 drawer cabinet. I didn't level it at all: I don't have a precision level. I did flatten it by shimming the right front foot until it cut straight.
 
Well, I got it mounted on the tool cabinet. Thanks to all for your input. :)) Now to finish cleaning it up and start making some chips.
View attachment 83396

I just got one of those! It's on the LMS cabinet. I've only made a few test cuts with it. Seems to be very capable. I'm upgrading from a Sherline, and just the ability to make interrupted cuts on small pieces of steel blows me away.

BTW, if I had to do it again, I'd do it your way instead of the LMS stand. It's a royal PITA to put together. If it weren't for my wife and her smaller hands, I'd still be trying to put it together.


Bob
 
Yes I’m bringing an old thread back from the dead. I also have an LMS High Torque 8.5x20 lathe. I’ve had it about a year and a half now. I also have LMS cabinet and while it is nice having storage under the lathe it is more flimsy than a wet noodle. I shimmed the base of both ends when I first got it and thought it was good. As time past I realized that the lathe was no longer level and I would get inconsistent diameters at the ends of test pieces. I took a DTI on a magnetic stand and placed the magnet on the chip pan and then had the DTI setting on the foot of the lathe with a 2” span. I then pushed the lathe in all different directions and found over .030” of movement. I also had my 6” Starrett level on the cross-slide and when I would push on the lathe it would move .015” and stay where I pushed it, not move back to its original position! If I were to do it again I would mount a steel plate (preferably boxed or square tubing) spanning the 2 feet of the lathe base. I have a 1-3/4” x 8” steel C-channel that I am mounting on top of the chip pan. Hopefully this will help with leveling and be consistent over time. I like the cabinet but just think that it’s just not strong enough to hold this lathe consistently in position. Also I forgot to add, I do have the cabinet mounted to a concrete floor in my basement with 8 lag bolts. I will report back here with how the C-channel worked.

I just got one of those! It's on the LMS cabinet. I've only made a few test cuts with it. Seems to be very capable. I'm upgrading from a Sherline, and just the ability to make interrupted cuts on small pieces of steel blows me away.

BTW, if I had to do it again, I'd do it your way instead of the LMS stand. It's a royal PITA to put together. If it weren't for my wife and her smaller hands, I'd still be trying to put it together.


Bob
 
HMF let me know about your reply, and it's pretty interesting. I've never measured my lathe like you mention.

When you get your mod done, it would be cool to post a picture of it. I'd be interested in what you do.

Are you lifting the lathe off the chip pan and putting your C-channel between the lathe's feet and the chip tray, or putting it on top of the feet in the tray, as it's mounted now?
 
Before I mounted the 29” long C-channel to the cabinet I did a few tests to see how sturdy it was. I took a dial indicator on a magnetic base and extended the arm as far as it would go which was about 14”. I then placed the magnetic base on the top in one corner and placed the indicator tip in the middle towards the opposite side. My goal here was to measure the flex and flex It! I layed the channel on a flat piece of concrete and propped up one corner about a 1/2”. Without even applying pressure to measure the flex it already showing .020” twist. When I applied a twisting motion I got .050” in each direction. Needless to say this C-channel isnt going to work so I decided that a larger piece of steel along with the C-channel was necessary. I have 2 pieces of A36 3/4” thick steel plate thats 6” wide by roughly 14.5” long. I Stick welded these 2 plates to the top of the C-channel. I got a tiny bit of warpage from the heat of welding these 2 plates to the C-channel but nothing that cant be shimmed plus I have to shim to get the small twist out of the bed anyway. Here is a picture of the base. With the indicator mounted the same way I get maybe a thou twist. The entire base weighs 60 pounds, Today I just mounted the base to the cabinet. I am now in the process of drilling and tapping 6 M8 holes for the studs to mount the lathe.

FD780D56-0E1F-454A-8D4F-4969D0B417B2.jpeg
Please ignore my ground down welds on the end of the p base. I can usually get good welds when welding flat but flat welds on the side I am just learning. I know what I did wrong with my stick angle. It may not look pretty but theres good penetration as I tested the same welds on a spare piece of the 3/4” plate and C-channel. Also, in the below picture you can see the square sheet metal platforms under the C-channel which is what the lathe originally mounted to. They are made from 3/64” plate and spot welded to the top tray of the cabinet.
6207D550-3ACC-4326-A545-C89E63668804.jpeg


HMF let me know about your reply, and it's pretty interesting. I've never measured my lathe like you mention.

When you get your mod done, it would be cool to post a picture of it. I'd be interested in what you do.

Are you lifting the lathe off the chip pan and putting your C-channel between the lathe's feet and the chip tray, or putting it on top of the feet in the tray, as it's mounted now?
 
I'm not going to say anything about welds because I can't weld and don't see a lot of difference between your welds and the little spots on the sheet metal of the cabinets. I've seen a billion welds like that.

I am surprised though that you can twist that C-channel .050 by hand. Seems like a lot. I guess something held one end and you twisted the other?

When you're using the lathe, where does that twisting force come from? Does it come from cutting at the end of long pieces? It seems like anything that would cause twist would have to be pretty aggressive. Wouldn't it be twisting the lathe around the long axis and get transmitted to the base?

Guess I just don't picture the forces involved.
 
Take a look at the 2nd picture again. There is a major difference between my continuous arc welds and the chinamen’s MIG spotwelds on the cabinet. The MIG spot welds penetrated the riser but not the table top as can be seen in the picture. My welds as I said, may not be pretty but have good penetration. I also ground down some of the welds because I’m not so proud of their appearance, not to hide a ****ty weld. If you watch a little bit of welding videos you will come to the understanding that appearance of welds doesnt totally determine penetration. It may lead someone to assume they are not adequate but appearance isnt everything, There is a lot of skill required to master a perfect arc weld, especially joining 2 vertical pieces. I’ve had a lot of help from what I would consider a master welder. Starting, stopping, different angles, amperage, drag angle, cleaning up slag after the weld, joining 2 substantially different thckness parts together, etc. Actually, from the 2 photos I posted above, you can only really get a good look at the ends of my part. What you cannot see are the welds joining the 2 3/4” pieces and along the length of the part that are actually pretty decent. The only weld that actually determines the rigidity of the 3/4” plate is the joining weld in the middle. Besides, these welds on the ends are not that important as the 3/4” plate did not prove to be any less flexible than before I welded it to the C-channel. I welded the C-channel to the 3/4” plate as I needed a way to fasten the 3/4” plate and I thought this was a good way of going about it. I could have spot welded the 2 pieces together and the 3/4” plate would not have gained a substantial amount of rigidity. Now the cabinet is a different story. If the cabinet would have been welded fully it would have helped but the material its built from is just not thick enough to withstand flexing and bending.

No I did not apply a lot of force to the C-channel in order to have it flex what it did and I had no help. C-channels really arent impervious to twist. They have their areas of strentgh but only when joined with other components to form a structure that must not be to rigid such as bridges and skyscrapers. I was innitially wrong in assuming the C-channel would be addequate. It flexes and twists from its own weight which was around 15lbs of I remember correctly. All together, the 3/4” plate and the C-channel weight 60 lbs.

In regard to flex while using the lathe, I can see it while turning 2 identical parts. This is a tabletop lathe, and while it is the bigger of its cousin (the 7x14) it requires a solid base to mount to. Just moving the carriage from one end to the other applyies weight to the bed unevenly on the opperators side and the transfer of weight applies force to the beds legs and that transfers to the cabinet. What I am seeing is totally different than a lathe mounted to a solid wood countertop. Granted most mounting will vary, but in general its a rigid setup disregarding the movement as seasons change. As I said previously, I can physically apply pressure to a portion of the lathe and after I release the pressure the damage has been done. This pressure physically tweaks the entire cabinet and in effect throws the bed out of alignment.

I now have the lathe mounted to the base. Rather than use shims to get it into alignment I used an epoxy. I have yet to test it out. Hopefully in the next day or 2


I'm not going to say anything about welds because I can't weld and don't see a lot of difference between your welds and the little spots on the sheet metal of the cabinets. I've seen a billion welds like that.

I am surprised though that you can twist that C-channel .050 by hand. Seems like a lot. I guess something held one end and you twisted the other?

When you're using the lathe, where does that twisting force come from? Does it come from cutting at the end of long pieces? It seems like anything that would cause twist would have to be pretty aggressive. Wouldn't it be twisting the lathe around the long axis and get transmitted to the base?

Guess I just don't picture the forces involved.
 
I really do like having the ability to roll the lathe out of the way when it's clean up time. I even have my little bench mill mounted on one. There's a thread or two where I've posted pics of my little shop if interested in doing a search.

I've talked to one or two people who own that LMS lathe, but not sure they hang out here.

I'm also a pioneer, as I don't think there are any other SB 8ks on this board. But I'm quite comfortable being a loner. :))

Bill
Don’t you also have a somewhat unique milling machine?
 
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