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View Full Version : New member with possibly dumb question about building a lathe base.



seattle smitty
06-24-2014, 12:23 PM
I am an old, but still rank amateur "machinist," have had a Craftsman/Atlas lathe and a Taiwan vertical mill in the past. I recently bought an older Enco 12X36B lathe, no gap. By the look of it, it had been used very little, though it is very dirty. I know enough about Chinese tools to consider them conditionally-acceptable for my sort of light-duty, hobby-level use, the condition being that you regard them as pre-assembled kits that the buyer should completely disassemble, clean, de-burr, chamfer, replace rough-feeling bearings, and then assemble, mount and level, and adjust. I have this chore ahead of me for my new-old lathe.

My question is about building a base for it. Previous owner had it on a heavy homemade wooden base. The guy was trying, but I doubt he did any leveling, and even if he did, the wooden base has surely settled since then, and will continue to move. I'm going to weld up a heavy steel base (incorporating cabinet space underneath). I know that any welding I do locks stresses into the finished assembly; time and vibration will tend to unlock some of those stresses and cause things to move around a little. I don't especially want to spend the money to have my finished lathe-base stress-relieved, nor machined. As stated, this base is going to have some real mass to it, and enough bracing to keep it rigid . . . but maybe not on the scale of accuracy needed for a lathe. I suppose I could peen each weld, though there will be lots of welds, and possibly it would help to "ring" the finished base by whacking at it for a while with a heavy hammer (Yes? No?). But maybe this is getting carried away. No doubt some of you have welded up your own machine bases. How much do they move around, in service? With the base lagged to the shop floor, I'll check the mounting pads for level and add shims as needed before mounting the lathe. Should I expect to have to re-level the lathe very often after that?

Also, I understand that a cast iron base is more desireable for reasons of dimensional stability and vibration damping. But I have to go with welded steel. Has anyone found that putting some sort of vibration absorbing material between the steel base and the lathe, say pads of Delrin, has value?

I suppose I should have waited for an old American machine to come up, but the price seemed okay, so it got this Enco while I could, and think it will do for my needs.

Ian B
06-24-2014, 12:41 PM
Hi Smitty,

You mention 'level' a couple of times. Lathes don't particularly need to be level to function properly - lots of ships have lathes in their machine shops, these work just fine!

What's more important is that the surface that you bolt your lathe to is flat, and doesn't impose any stresses on the bed. For home shop use, I'd not expect any real noticeable variations in accuracy due to a welded frame moving. However, if you are after mass (which always seems good to me), then how about casting a concrete slab and grouting & bolting to that? The slab can be raised up on a welded steel frame.

Good luck,

Ian

spongerich
06-24-2014, 12:56 PM
What about looking for a cabinet/chip pan from a similar sized South Bend / Logan / Hardinge? By the time you buy the steel, you might find a suitable base for the same money.

RPM22
06-24-2014, 01:11 PM
I read an account where the Atlas lathes being mass-produced for their WWII duty were recommended by Atlas to be mounted on a concrete slab - this was done to handle the stress to the bed of almost continuous machining.
As Ian B mentions, it's more important to be flat and stable for lighter-duty lathes - my 12x30 Atlas is mounted on a 1 1/2" thick plywood table-top covered in Formica, screwed to the wall - it has never had problems of the bed warping.
Richard in Los Angeles

Ric

bob308
06-24-2014, 01:19 PM
I wish people would put a general location. you could be across the street around the corner or across the country from me . if the first 2 I would be more then will to help you out.

I had a 12" atlas that I mounted to a bed made from 8x18 h beam milled the top flat put legs on it bolted on the lathe. I have a 9" south bend mounted on a stand made out of tubing now.

jlevie
06-24-2014, 01:26 PM
Since you will be building the base, there is a good chance that you won't wind up with a dead flat surface. I'd say the build the base and shim it's feet until the top is pretty level. Then set the lathe on and shim it for cross level. It probably won't need any attention for a long time, but you should still check it periodically.

ptjw7uk
06-24-2014, 01:27 PM
I wish people would put a general location. you could be across the street around the corner or across the country from me . if the first 2 I would be more then will to help you out.

And you are !

andywander
06-24-2014, 01:38 PM
Funny-you don't list your location!


I wish people would put a general location. you could be across the street around the corner or across the country from me . if the first 2 I would be more then will to help you out.

I had a 12" atlas that I mounted to a bed made from 8x18 h beam milled the top flat put legs on it bolted on the lathe. I have a 9" south bend mounted on a stand made out of tubing now.

andywander
06-24-2014, 01:39 PM
All true-but one of the easiest ways to make a surface flat is to make it level.


Hi Smitty,

You mention 'level' a couple of times. Lathes don't particularly need to be level to function properly - lots of ships have lathes in their machine shops, these work just fine!

What's more important is that the surface that you bolt your lathe to is flat, and doesn't impose any stresses on the bed. For home shop use, I'd not expect any real noticeable variations in accuracy due to a welded frame moving. However, if you are after mass (which always seems good to me), then how about casting a concrete slab and grouting & bolting to that? The slab can be raised up on a welded steel frame.

Good luck,

Ian

dian
06-24-2014, 02:06 PM
http://i973.photobucket.com/albums/ae218/romandian/mkbohrer034.jpg (http://s973.photobucket.com/user/romandian/media/mkbohrer034.jpg.html)

http://i973.photobucket.com/albums/ae218/romandian/DSC00404.jpg (http://s973.photobucket.com/user/romandian/media/DSC00404.jpg.html)

this is an epoxy concrete table on hockey pucks. its heavier than the lathe. just great, it dampens exteremly well and is rigid enough to straighten the bed.

probably easier, than welding something up and less expensive too. the top layer of epoxy will be lelf leveling.

(i know, i posted this before.)

Mike Amick
06-24-2014, 02:11 PM
I wish people would put a general location. you could be across the street around the corner or across the country from me . if the first 2 I would be more then will to help you out.


I agree .. but .. the suggestion seems more valid when you, yourself are willing to put your location in your account info.

Royldean
06-24-2014, 02:16 PM
funny-you don't list your location!

burn!

jep24601
06-24-2014, 02:23 PM
In Bob308's defense - HE wasn't the one asking for help.

tlfamm
06-24-2014, 02:39 PM
this is an epoxy concrete table on hockey pucks. its heavier than the lathe. just great, it dampens exteremly well and is rigid enough to straighten the bed.

probably easier, than welding something up and less expensive too. the top layer of epoxy will be lelf leveling.

(i know, i posted this before.)


That's beautiful - shop-made or commercially made? What goes into the mix of "epoxy concrete"?

chipmaker4130
06-24-2014, 02:50 PM
Build it any way you want. With the possible exception of the type shown above by dian, you'll need to periodically re-level your lathe anyway. (most people here already know that 'level' doesn't mean level in the common sense. Its just the terminology/process we use to flatten the bed)

michigan doug
06-24-2014, 03:22 PM
Level/flatten the base (made with wood/metal/concrete) then level the lathe on the base by shimming the feet.

Repeat every 12 months unless you can tell something is funny.

I ran my old pos shoptask on a base made of 2 x 4's glued and nailed together to form a solid/laminated top 3 1/2" thick. Then I put a sheet of plywood on top of that, glued and screwed. It never moved around much. Not as good as a heavy steel or cast iron base, but it was cheap fast and effective.

doug

bob308
06-24-2014, 03:33 PM
thought it was in there I added now. oversight on my part. but would still help if he is close.

Gettysburg pa.

The Artful Bodger
06-24-2014, 03:51 PM
Hi, I had an entire concrete bench cast and I am very pleased with it.

https://farm7.staticflickr.com/6140/6030221621_170e654cb4.jpg

Joe_B
06-24-2014, 04:25 PM
https://www.youtube.com/watch?v=ztA-0KSi1FM

I found this a week or so ago, may be of interest to you.

Glug
06-24-2014, 06:33 PM
I like this method. Haven't done it.


http://bbs.homeshopmachinist.net/threads/44193-Concrete-work-bench?p=602672#post602672

dp
06-24-2014, 06:42 PM
thought it was in there I added now. oversight on my part. but would still help if he is close.

Gettysburg pa.

I'm going to guess that with a nick like Seattle Smitty he's probably a lot closer to me than to you, and I'm 300 miles farther from Seattle now than the 10 miles distance I was a month ago before I moved.

Anyway - I bought a leg set from Grizzly in Bellingham, a 2" solid core door from Home Depot, and a drain pan from O'Reilly's auto parts in Bellevue and that worked for 7 years under my Grizzly lathe.

PStechPaul
06-25-2014, 12:32 AM
I really need to mount my lathe on a better base. At the moment I have it bolted to a piece of 2x12 PT framing lumber which is in turn bolted to a rather flimsy bent metal machine tool frame. It sits on a rather rickety plywood floor that is warped and getting worse.

http://enginuitysystems.com/pix/tools/Lathe_1173_800p.jpg

For my mill/drill I made a frame from 4x4 and 6x6 lumber and a top made of 2x4s and a thick particle board top. The whole thing is mounted on heavy duty (900 lb) casters so I can roll it away from the wall for cleaning and reposition it as needed. I have a chain fall bolted to the ceiling joists so I can maneuever the table under it and lift the mill and lower it onto a dolley.

For the lathe, I'm thinking about using the two drawer sections from a large, heavy, wooden desk, the top for which has warped and may be unusable. Each of the drawer sections has four very stout legs, and the drawers would be handy for tooling storage. I might be able to use a bunch of 2x4s to make a solid top, and I might even be able to bolt the original top to them to take out the warp, but it may be better to use thick particle board possibly covered with Formica or similar material. I have another set of casters I could use, although that might not be a good idea. However, I also have some retractible "feet" that could lift the table so they could support it instead of the casters.

My lathe is a HF 9x20 so it's only about 250 pounds and a footprint of about 16" deep and 37" wide. It might even fit on the opposite side of my milling machine table, or I could fit them both on a new table the size of the wooden desk, which was about 30" x 60". It might be convenient to move the table with both machines (and also a vise and maybe a small drill press and grinder and arbor press), into the middle of the room and have access to hand tools and materials on the walls, and then roll it back when finished with them. Hmmmm. :cool:

dian
06-25-2014, 07:33 AM
That's beautiful - shop-made or commercially made? What goes into the mix of "epoxy concrete"?

i poured it in place. its concrete aggregate mixed with epoxy. i added some fibres too.

DS_park
06-25-2014, 07:45 PM
I wish people would put a general location. you could be across the street around the corner or across the country from me . if the first 2 I would be more then will to help you out.

I had a 12" atlas that I mounted to a bed made from 8x18 h beam milled the top flat put legs on it bolted on the lathe. I have a 9" south bend mounted on a stand made out of tubing now.

With a user name seattle smitty, I'd say the greater Seattle Washington area is a good possibility.

DS_park
06-25-2014, 07:56 PM
seattle, welcome to the forum. Lots of good folks here with much experience and many opinions.

I sought similar advice when attempting to redo my bench top a few weeks ago. see- http://bbs.homeshopmachinist.net/threads/63354-Bench-Top-Advice-Sought

My take on all the feed back is there are many acceptable solutions to a bench project. Choose a method/materials you are comfortable with and that fits your budget (money and time).

It was more important to me to test out my refurbished lathe first so I simply repaired and reinforced my current bench.

For a future project I will build a totally new bench. I like wood for the bench top so I will probably stick with that but will incorporate metal plates under the lathe bed feet. Frame and legs will be steel.

DS