Anchoring a Lathe to a Slab

Z

Zebra13

Member
Gents,

I am finally getting around to setting-up the machines in the shop of our new pad. All is well, except for my Emco Super 11 lathe. While it is a little jewel of a machine, it is light, to the tune of 850 or so pounds. As such, it has a touch of the wobblies that you can feel when running it, which is unsat. So I've started entertaining the idea of anchoring it to my slab.

One idea I've had is to make riser blocks out of aluminum, about 5 inches tall, drilled and tapped to accept a length of threaded rod. The rods would go through the holes in the base of the machine, with nuts/washers being used for leveling, much like conventional machinery leveling feet. The purpose of the riser blocks is to raise the lathe so as to be more comfortable whilst working away. My other lathe is set-up similarly and it makes a world of difference comfort wise during long sessions at the lathe.

None of the above is new, but my thought was using a high-strength epoxy of some sort to anchor the riser to the slab, which I've never heard of anybody doing. This would, in effect, anchor the lathe to the slab.

While I'm no Epoxiologist, it would seem that modern epoxies would be plenty stong for this application, especially considering the stress on the epoxy joint would be minimal. Further, my Emco has leveling bolts on the bed, i.e., I can adjust the bedways INDEPENDENT of the conventional leveling process. If the lathe stand was seriously askew, and conventional leveling would unduly stress the epoxy joint (think twisted lathe stand being torqued straight during the leveling process), I can mitigate this stress by using the leveling/adjustment capabilities of the bedways.

Another option would be to pour the riser blocks out of concrete and epoxy them to the slab, if this would result in a stronger bond.

So what say you guys? If feasible, do you have any epoxy recommendations?

Thanks for your replies,
Justin
 
I AM an epoxiologist and will state as absolute fact that you cannot epoxy that thing down to the slab. Well, not and get it to "stick."

Were it me (and I know IT AIN'T!) I'd consider bolting it down onto hockey pucks
 
alinwa said:
I AM an epoxiologist and will state as absolute fact that you cannot epoxy that thing down to the slab. Well, not and get it to "stick."
Click to expand...

In my yute, when in urban environments, we used to take left over Hilti epoxy (something like HY200?) and glue quarter to sidewalks for entertainment....

I’d bet there’s still several odd epoxied rock formations on mountain tops all over CA and NV...
 
Lifted this from Long Rifles Inc. This is one epoxy application I would have bet not to last.

"We also offer a machined/welded stand for our vise. The floor plate can be bolted or epoxied* to the floor.

*LRI relocated to its current facility in 2011. The barreling dept stand was glued to the floor using JB weld. It has never failed. This was done because our shop has radiant floor heat and the risk of accidentally cutting the tubing matrix embedded in the concrete was just something we weren't willing to gamble on.

Simply grind the floor clean with an abrasive pad (36 grit), remove the powder coating from the bottom side of the floor plate. Tape off the plate's footprint. Mix JB Weld and spread an even layer approximately 1/32" thick. Place the stand inside the square, peel the tape, and let it rest for a full 48 hours. (if the floor is cold, you may want to wait an extra day) Assuming all mating surfaces are sterile, you can work with confidence once the resin is cured. Should the stand ever need to be used, a rosebud torch can be applied to the base to warm it up and break the bond. Know that this will almost certainly ruin the powder-coat finish so its best to plan well ahead when deciding on placement."
 
Single-point non-working loads with large surface area will rarely fail.

You can weld an 8" square flange onto a 4" steel post and either bend the post or rip up a hunk out of the floor. I can't imagine a vise stand, grinder/buffer/worktable failing.
 
NezRongero said:
Lifted this from Long Rifles Inc. This is one epoxy application I would have bet not to last.

"We also offer a machined/welded stand for our vise. The floor plate can be bolted or epoxied* to the floor.

*LRI relocated to its current facility in 2011. The barreling dept stand was glued to the floor using JB weld. It has never failed. This was done because our shop has radiant floor heat and the risk of accidentally cutting the tubing matrix embedded in the concrete was just something we weren't willing to gamble on.

Simply grind the floor clean with an abrasive pad (36 grit), remove the powder coating from the bottom side of the floor plate. Tape off the plate's footprint. Mix JB Weld and spread an even layer approximately 1/32" thick. Place the stand inside the square, peel the tape, and let it rest for a full 48 hours. (if the floor is cold, you may want to wait an extra day) Assuming all mating surfaces are sterile, you can work with confidence once the resin is cured. Should the stand ever need to be used, a rosebud torch can be applied to the base to warm it up and break the bond. Know that this will almost certainly ruin the powder-coat finish so its best to plan well ahead when deciding on placement."
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If the contractor was smart enough to bed the radiant slab "wersbo" tubing in sand under the slab rather than in the concrete,anchoring issues would not exist.
 
If you are OK with casting concrete rider blocks, I would epoxy rebar into the slab at the block locations, roughen the concrete surface where the blocks would go, then use a bonding agent on the slab when you place the concrete. Structural engineers accept properly epoxied anchor bolts and/or rebar all the time. The key is "properly", making sure all the dust is cleared from the drilled hole. There are pretty good bonding agents used when placing concrete toppings on slabs. I wouldn't rely soley on a bonding agent, the epoxied rebar would keep it where it needs to be.

Edit:
Let me add, the weight of a lathe should keep riser blocks in place. I raised mine 5" with cast blocks, set in place, and they haven't moved in 10 years I think. If I recall, Mr. Tooley had pieces of steel rounds (4 or 5 inch) cut to place under his lathe, I don't think he anchored those.
 
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Wedge Anchors might be part of the answer.

Build your risers to length.

Wield a flange onto each riser.

The flange will be used to bolt risers to concrete slab via the Wedge Anchors.

I would bolt the risers with flanges to the lathe, then drill the holes into the concrete, using the flange holes as a guide.

If you ever want move the lathe unbolt it and cut and grind the bolts flush with the floor.

Anyone ever use motor mounts for this type of application?
 
I pour, mend and patch concrete for a living > www.sierraconcretefoundations.com < and agree with all the methods listed.... except just gluing her down.

My issues with only gluing the lathe and block are that the lathe, under temperature variations grows and shrinks in length, and while the concrete floor expands/contracts at very nearly the same rate (ie, similar expansion coefficient) it's driven by a different set of variables. In other words, the lathe and the concrete floor are both 'alive' but not part of the same unit, and that epoxy under a working/vibratory load will fatigue/fail.

Epoxied joints hate flex/vibration



edited to add, link does not work..... don't know why
 
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Your pad will constantly move, let the lathe float on its own/IE leave the anchor bolts loose.

NEVER bolt a machine tool tight yo a pad.


,
 
JerrySharrett said:
Your pad will constantly move, let the lathe float on its own/IE leave the anchor bolts loose.

NEVER bolt a machine tool tight yo a pad.


,
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Works fine if the pad is large enough.
The concrete pad under our largest lathes was five feet thick.
It had lathes as large as 40 feet used to turn casting up to
around six feet in diameter.
I have a basement pad that is around 8 inches thick.
It does not have ANY cracks in it.
The 14 x 48 lathe bolted to it is not moving any time soon.

I generally prefer to use epoxy secured threaded inserts and
them level everything at the top of the mounting bases.

The bases are used to hold the inserts in position during curing of the epoxy.
When fully cured tighten the nuts up.

Final leveling and alignment is between the drip pan and lathe feet.
The Starrett 12 inch Machinist Level is very sensitive.
You would swear the glass tube is an almost perfect cylinder.
It moves plenty with 0.0010 inch shim under one end.
Rated at 0.005 in per foot.
 
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Gents,

Thank you all for your replies. The epoxy idea has been relegated to the "Good Idea if it didn't Suck" file.

All right, Sharrett...you've set-up a machine or two in your time. How would you go about setting-up my lathe given the issues presented above?

Justin
 
The loads on a lathe with a large out of balance item being turned are huge.

We anchor them so they do not tip over.
 
Not completely relevant, but I'll tell it anyhow. Back in the summer of 1970 or '71 I was working construction in Springfield, Vermont. The Jones & Lamson plant was just over the bank from my parent's house. I was on a job there to bust up a machine base with jack hammers. The whole shop was operating so we had to build a plastic house around the base and keep it wet down with water for dust control. That sucker was about 20 feet square and 6 feet thick. Full of rebar of course. We hammered at it for 8 hours a day with 90 pound jack hammers for weeks. Every once in a while we'd stop and cut off the exposed rebar with torches. I hated that job. All my fingernails got blisters under them and then they fell off.

The base we replaced it with was much bigger on a side, but only 4 feet thick. I never saw either machine. I do remember that there were pallets of 155mm artillery shells on the loading dock that had probably been there since WWII.

Ironically, after I finished college, I ended up just up the river at Fellows Gear Shaper running a Reishauer involute grinder making gear cutters. Not part of the plan for a religion major, but it got me into my first programming job. Still doing that today. Better to be a gainfully employed programmer than a starving professor wannabe.
 
vtmarmot said:
Not completely relevant, but I'll tell it anyhow. Back in the summer of 1970 or '71 I was working construction in Springfield, Vermont. The Jones & Lamson plant was just over the bank from my parent's house. I was on a job there to bust up a machine base with jack hammers. The whole shop was operating so we had to build a plastic house around the base and keep it wet down with water for dust control. That sucker was about 20 feet square and 6 feet thick. Full of rebar of course. We hammered at it for 8 hours a day with 90 pound jack hammers for weeks. Every once in a while we'd stop and cut off the exposed rebar with torches. I hated that job. All my fingernails got blisters under them and then they fell off.

The base we replaced it with was much bigger on a side, but only 4 feet thick. I never saw either machine. I do remember that there were pallets of 155mm artillery shells on the loading dock that had probably been there since WWII.

Ironically, after I finished college, I ended up just up the river at Fellows Gear Shaper running a Reishauer involute grinder making gear cutters. Not part of the plan for a religion major, but it got me into my first programming job. Still doing that today. Better to be a gainfully employed programmer than a starving professor wannabe.
Click to expand...



I machined the bodies and nose cone for the 155mm artillery shells at Intercontiental MFG in the middle to late 60s. I also worked on the 500lb and 2,000lb bomb lines before transferring into the tooling dept. I did run a jacjhammer in the summer of 1960. I think that was the source of my carpel tunnel problems.
 
Well designed grade beams are a serious PITA to remove.

The rebar gives the composite beam the same strength in tension
as the concrete has in compression.

We had a very large vibration table.
About 10 feet by ten feet.

We used it for testing entire racks of U-2 equipment.

The concrete base under it wend down to bedrock.

When it was running the whole building vibrated.

Most larger test had to be run at night when
the place was pretty empty of employees.
 
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