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oxford
12-24-2011, 10:12 AM
Hi, new to this forum. I am going to be finishing up the inside of my garage soon and the Clausing 5914 will be set into its new home soon. I was wondering what the thought are of anchoring the lathe down to the concrete floor? Is it really needed? I know none of the machines at my work are bolted to the floor, although its not like they they always do things right there:rolleyes:. Thanks for any input.

Also is there a section for wanted, for sale, barter on this forum?

loose nut
12-24-2011, 10:42 AM
Also is there a section for wanted, for sale, barter on this forum?

Not on this forum, sorry.

When you decide to bolt down your machinery be careful. Most garage concrete floors aren't very thick, 2 to 3 inches maybe. When I was bolting down my lathe I drilled holes for the REDHEAD anchors (the kind that you drive into a hole then tighten the nut to expand the base) that I was going to use and the first one I dropped into a hole fell through into a cavity under the floor. Watch the hole depth.

dalee100
12-24-2011, 10:43 AM
Hi,

I'm not a big fan of bolting machines to the floor. Buildings and floors move with the seasons and time. That movement can be transferred and reflected in your lathe with twist and warp.

And if you are concerned about your lathe walking across the floor during use, just go a bit slower and lighter on the cut.:)

dalee

oxford
12-24-2011, 11:00 AM
And if you are concerned about your lathe walking across the floor during use, just go a bit slower and lighter on the cut.:)

Thanks. No I am not really concerned, and would rather not mess with bolting it down if I don't have to. I was just not sure if good practice to do so.

Loose nut, I belive the floor to be fairly thick. I had to cut out a section of floor near the footing to move a water line and it was around 6" there, but who know what the rest of the floor is. Good call on not going to deep with the acnchors though.

jugs
12-24-2011, 12:29 PM
Hi,

I'm not a big fan of bolting machines to the floor. Buildings and floors move with the seasons and time. That movement can be transferred and reflected in your lathe with twist and warp.

And if you are concerned about your lathe walking across the floor during use, just go a bit slower and lighter on the cut.:)

dalee

X2

And if you are concerned about your lathe walking across the floor during use or being top heavy/unstable -

just mount/bolt the machine on an oversize steel pallet with 4" high feet, load the spare areas of the pallet with heavy tooling/steel offcuts etc,
- it makes the machine stable,
-reduces vibration,
-allows easy movement of equipment (with a pallet truck) when you need more space,
-raises the machine to correct your posture,
-gives extra toe room,
-etc........& you don't have to go a bit slower and lighter on the cut. :) :D

All my equipment upto 2.5ton is "portable" like that, the 4.5ton horizontal borer....... just sits on the floor:D

Forrest Addy
12-24-2011, 12:54 PM
In a perfect world a machine tool would be rigidly attached to an isolated reinforced concrete foundation, dully cured for six months, leveled and aligned, and finally grouted. In the real world of the home shop we have solid seeming concrete floors that may be only a few inches thick over subsided grade. I've leveled machine tools where merely walking around the machine caused the vial to register my passage.

The best you can do is the best you can do. Set the machine is place and level/align it. If the floor flexes a trifle it will have little effect on small scale work. I don't suggest you bolt it down unless you machine large unbalanced workpieces.

If you discover subsidence of the soil underlying your concrete floor, you might call in a concrete guy to consult about pumping grout under the floor. They drill holes on a 4 ft grid and pump in a highly fluid grout to fill the space. If the subsoil is stable that will permanently cure any floor deflections that plague you. Machine tools of considerable wieght and those having large moving tables (planers and horizontal mills for example) will certainly benefit from the solid support. A lather weighing only a ton or so will accrue no significant benefit.

Dr Stan
12-24-2011, 12:57 PM
As others have indicated it is not common practice to bolt a machine tool to the floor. The only times I've seen this is on board ships so they would not move in heavy seas.

The coefficient of contraction & expansion for concrete & cast iron is quite different. If you bolt the lathe to the floor with the changes in the seasons over time you will put a serious twist &/or bend in the machine. It will also make it much more difficult to level the lathe.

If for some reason you are concerned about the lathe tipping over or moving, determine the high spot of the machine and secure it with one anchor bolt. That would hold the machine in place and still allow for the differential in the expansion & contraction of CI and concrete.

BTW, welcome to the forum.

loose nut
12-24-2011, 01:26 PM
The best you can do is the best you can do. Set the machine is place and level/align it. If the floor flexes a trifle it will have little effect on small scale work. I don't suggest you bolt it down unless you machine large unbalanced workpieces.


What do consider small scale under 1# or under 100#.

If a machine is not bolted down IE: sitting on homemade "hockey puck" levelers, would adding extra weight to the base help. When I made my lathe stands, they are 22" square x 16" (I think ????) high, I left a port so I could load them up with ballast. About 200# each. This would bring the weight of the two stands to about 900# plus the weight of the lathe a 13 x 40. about 1100#.

I do feel a slight vibration at some speeds.

oxford
12-24-2011, 01:31 PM
Thanks for the replies. Like I said, no concern for it walking across the floor, tipping or anything. I do belive that the manual for the lathe does state for it to be anchored to the floor, and I would have to look but I am positive that the leveling feet on it are setup for it. I was just wondering if people were doing it.

I'll have some more question when it comes time to do the VFD conversion on it:)

dian
12-24-2011, 01:37 PM
"The coefficient of contraction & expansion for concrete & cast iron is quite different."

steel and concrete are the same. is cast iron different?

jugs
12-24-2011, 02:15 PM
The coefficient of contraction & expansion for concrete & cast iron is quite different. .

http://smileys.on-my-web.com/repository/Confused/stupid.gif Sorry stan but they are almost the same

coefficients
Steel =10.8
iron =11.8
concrete =12
:D

edit- thats 10-6/C

danlb
12-24-2011, 02:25 PM
In my area earthquake safety is a concern. Large, top heavy machines have a habit of laying down and resting after a quake. There are a lot of ways to 'anchor' them so that they do not tip or shuffle across the floor without inflexibly afix them to the floor.

I wish I had not written that. Now I have to think about doing it correctly in MY garage.


Dan

JoeLee
12-24-2011, 02:32 PM
I have a Clausing 5913. Never bolted it down. It has a nice set of vibration dampening and leveling pads. At 1100 Lbs. + it's not going anywhere. If I want to move it...... no problem. Also agree with all the other comments on expansion etc.

JL.................... Merry Christmas............

Dr Stan
12-24-2011, 02:36 PM
"The coefficient of contraction & expansion for concrete & cast iron is quite different."

steel and concrete are the same. is cast iron different?

In the imperial system the coefficients are:

10-6 in/in degrees F

cast iron 6.0

Concrete 8.0

Steel 7.3

These factors are from http://www.engineeringtoolbox.com/linear-expansion-coefficients-d_95.html

Naturally the amount of force/stress imparted on the secured machine tool would also depend on the temperature differentials over the seasons.

On edit: I guess the same or different is a matter of perspective. In any case I would not use more than one anchor bolt to secure a machine tool.

As to earthquake prone areas, that's a different issue. I'd probably go with a single anchor or something like a heavy cable or chain attached to or looped around the machine tool with the other end securely anchored to the floor. I'd have a minimal amount of slack in the cable or chain to allow some movement, but to hopefully prevent tipping. I'm interested in hearing if any commercial shops on the west coast have taken steps to reduce earthquake damage.

Kenny G
12-24-2011, 04:05 PM
I have a Clausing 5913. Never bolted it down. It has a nice set of vibration dampening and leveling pads. At 1100 Lbs. + it's not going anywhere. If I want to move it...... no problem. Also agree with all the other comments on expansion etc.

JL.................... Merry Christmas............

I would fully agree with JoeLee. My Colchester Triumph is fitted this way and never shown any problems.
Kenny G:)

loose nut
12-24-2011, 04:12 PM
In my area earthquake safety is a concern. Large, top heavy machines have a habit of laying down and resting after a quake. There are a lot of ways to 'anchor' them so that they do not tip or shuffle across the floor without inflexibly afix them to the floor.

I wish I had not written that. Now I have to think about doing it correctly in MY garage.


Dan

What about mounting your equipment on big springs.:D :D :D

John Garner
12-24-2011, 04:19 PM
The city of Mountain View requires that the machines in my employer's shop not only be bolted to the foundation, but that they be surrounded by bolted-down stop blocks to isolate the hold-down fasteners from shear loads.

Dr Stan
12-24-2011, 04:42 PM
The city of Mountain View requires that the machines in my employer's shop not only be bolted to the foundation, but that they be surrounded by bolted-down stop blocks to isolate the hold-down fasteners from shear loads.

I expected as much, but I'm glad to have first hand confirmation. Thanks for the info.

Grind Hard
12-24-2011, 05:22 PM
The machines I have in my workshop are on machine mounting pads.

I managed to convince the sales-rep to part with a dozen of the "light duty" ones... which are plenty good enough for a mill and lathe seeing home-shop-type work.

The "new" stuff I have coming in will be put on pads too, once they arrive. Should be in after the holiday.

barts
12-24-2011, 07:06 PM
In areas with significant probability of major earthquakes, some thought at least should be given to prevent toppling of top-heavy designs.

- Bart