Anchoring Machne tools to floor

The some of the smaller machines don't have provision for bolting them to the floor but all the bigger ones ive worked on do have leveling bolts and provision to anchor the machine to the floor. The ones that arent anchored are the ones that don't cut straight.

John

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John
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There was a mild earthquake in ny state about four years ago that was felt here in PA... I felt it about 6 am... At first I thought it was me until the glasses on the counter made some noise. It was somewhere in the saratoga area if i recall.

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John

Reply to
John

One of the possibles - have the bolts in the floor - and through the equipment with nuts on - but not tightened onto the metal. e.g. trapped from walking or bucking - e.g. safe from problems - but not torking the frame out of shape as it flexes in temperature during a season or day.

Martin

Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder

David Utidjian wrote:

Reply to
Martin H. Eastburn

According to David Utidjian :

O.K.

Hmm ... My Clausing 12x24" lathe has six holes -- four under the headstock pedestal, and two under the tailstock one. The manual for the lathe recommends (assuming that there is some slope as there is with my garage floor, designed to run water to the outside), that tapered shims be made up for the full length of the pedestal front and back edges. (Easy, if you have a big enough milling machine. :-) This is to avoid stress on the pedestal which will warp it over time, I suspect.

Probably -- unless you plan to put a big heavy workpiece well off center on a faceplate or in a 4-jaw chuck, and then go through the speeds looking for where you get resonance.

Where I worked, cut-off bolts just barely long enough to go through the feet were placed in putty to keep the inspectors from finding fault with the installation. :-)

With only four points of support, that might well work nicely.

Proably so -- just so they fill the holes better. :-)

You want more than that, I think. I had to get to the back of mine to install the taper turning attachment, and I have had to sit on the floor and remove the back panel of the headstock pedestal to access the motor to replace the starting capacitor a couple of times. (Next time, it gets a three-phase motor and a VFD -- both of which are already in hand), and once to replace the three paralleled belts running from the countershaft to the spindle pulley. There, it is nice to have room to lean back with the motor in your hands, without wedging your back against the wall.

Of course -- now this space is at least partially filled by my air compressor, but that is on wheels, so it can come out if I need to go in. :-)

You might be able to live without the bolts. I have, so far, with a machine about 50% bigger than yours in terms of swing, though the length between centers is quite a bit less.

Good Luck, DoN.

Reply to
DoN. Nichols

That is a good idea Martin.

The room these machines are in is temperature controlled. Over a year it does not vary much more than 10 degrees F. By my estimation the length of the cabinet will vary by about 0.00584" for a temperature change of

20 degrees F. The cast iron lathe bed by about 0.00472" and the concrete floor by about 0.0064" over the distance between mount points. The difference in length change is greatest between the cabinet and the bed... about twice that of cabinet and concrete. Naturally the actual geometry of the interactions can make a much larger change in alignments.

The way the bed is mounted to the cabinet appears to be designed so there can be some variation in the distances between mount points over time and temperature. Each mount point has an externally threaded bushing. The external thread on the bushing mates with internal threads on the actual bed of the lathe. The threads on the bed of the lathe pass right through to the underside of the bed. Then there are bolts that pass through the top of the bushing, down through the bed, through the cabinet top with nuts and lockwashers underneath. There is some clearance around these bolts and the ID of the bushings they pass through. The leveling of the bed is done by screwing the bushings up or down as required.

The manual from the manufacturer for this lathe claims that alignment was done at the factory before shipping by mounting and leveling the cabinet properly and then leveling the bed.

The bolts I was intending to use for mounting the cabinet to the floor will be smaller than the holes of the mounting tabs on the cabinet. 1/2" holes and 3/8" bolts. I could use 1/2" bolts as the holes are slightly larger than 1/2" some are even elongated but I don't think I can drill the holes in the concrete that accurately.

Seems to me that experience, opinion, and practice is mixed on whether to mount the lathe to the floor at all. Personally, I want to do the method that gives me the most precision. Practically, I have to do the method that I am required to do which is bolt the machines down. This isn't a home or privately owned shop.

Thanks again for your suggestion.

-DU-...etc...

Reply to
David Utidjian

The question is whether you have to satisfy the OSHA people or the company's safety engineer, who may have a different view of the regs. I remember one place I worked the safety engineer required that elaborate guards be put on a press that had been there since before WWII with no injuries in all that time. After the guards were installed they had five injuries in the next two years all associated with the guards.

This same safety engineer wouldn't issue a respirator to a guy spraying urethane because according to her elaborate air quality measurements that probably cost ten times as much as the respirator the guy didn't need one.

Reply to
J. Clarke

This is the exact wording:

"1910.212(b) Anchoring fixed machinery. Machines designed for a fixed location shall be securely anchored to prevent walking or moving."

I think this leaves some wiggle room . Add a pair of wheels to the headstock end that just barely clear the floor. If any questions come up, say the machines are meant to be moved/shifted from time to time depending on how they will be used...

Reply to
Leon Fisk

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