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How to properly raise a machine that sits on the floor?

Frigzy

Aluminum
Joined
Apr 26, 2018
I have a bulky (3000 lbs) milling machine, that stays on the garage floor. There is a tiny gap (3/8") between the machine's base and the floor. I want to lift the machine a little bit to install adjustable rubber legs. What is the proper way to do this? I think about a breaker bar, but I don't feel like it's safe - there is a lot of load and tension on the bar and it puts significant stress on the bottom of the machine, which is made of cast iron and may crack. The only crane I have is a 2-ton cherry-picker crane which I have really terrible experience with - last time I tried to lift the mill with that crane, it almost tipped over on me.

Thanks!

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A breaker bar is used with sockets to break tough bolts loose.

A riggers bar is a large prybar for lifting machines.

You could lift that little thing with a claw hammer or a 2' prybar. If that's scary for you then just drive wedges in.
 
Right in the front of the photo is a hole for bolting machine to floor.

Usually sized close for 5/8 threads.

Check hole size and drill out as needed to allow tapping for bolt.

Now use long all threaded high grade bolts to simply raise the machine carefull and slowly straight up...1/4 turn on each foot going arround it.

Place blocks or other spacers to support as you go.

The adjustable feet may have stud mount so tap to same size.

We lifted our 6800 pound L&S 6 inches to allow pallets under it this way.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk
 
A pinch bar or other heavy lever is the way to get started. (Around here, a breaker bar is a non-ratcheting socket wrench handle.)

You will need a stack of 1/2" hardwood plywood (better) or metal (not so good, slippery) plates at least 3x3" or 4x4" (6x6" is much better when the stacks get higher), perhaps a comparable stack of 2-3" thick hardwood blocking, a pinch bar, and ideally a toe jack. A second human with enough common sense to keep fingers out from under the machine can also be a real help. :)

You can possibly use high-quality softwood plywood, but my limited experience is that it will crush under the machine feet and end of the pinch bar much more readily than the hardwood plywood. Cheap CD plywood with internal voids filled with putty is strictly to be avoided for this procedure! Consider a sheet of hardwood plywood as an investment in your rigging tool kit. BTW, hardwood plywood here means all the plys, not just the wafer-thin veneer on the faces.

Using the pinch bar, raise one side of the machine and slide a plywood plate under each foot on that side. Make sure the foot bears on the center of the plate, not just near an edge (much less just near a corner). Move to the opposite side of the machine and repeat. If that's not high enough to get the toe jack under the edge, put a plywood plate on the floor where you were using the pinch bar and repeat. The machine is now 1" higher off the ground, which should be high enough to get a toe jack under the edge. If you don't have a toe jack, keep raising all the stacks 1/2" at a time, including the fulcrum stacks for the pinch bar.

If you need to protect the finish or surface coating on your floor, put a thin plywood plate under the pinch bar fulcrum even for the first 1/2" raising.

If you have a toe jack, after the machine is high enough, get the fulcrum plates out of the way, and use the toe jack to raise the machine more than 1/2" at a time (don't be reckless and tip it over), and increase the stack height accordingly. Alternate sides until the machine is high enough to get rollers, leveling screws or whatever under it. For convenience in manipulating the stacks and greater piece of mind, you can replace bunches of plywood plates with thicker blocking when the machine gets that high.

Now, if you put the plywood plates squarely under the machine feet, the odds are good the stacks of blocking are going to interfere with whatever you want to do with the machine. Not a major problem. The machine is now at a proper height. Work on one foot at a time. Put two stacks of blocking next to each foot. They will be a bit short. Raise that side/corner of the machine just a little bit. Pull out the original blocking stack and bring the two nearby blocks up to full height and set the machine back down again.

Tony's suggestion of tapping the base holes and jacking it up also works, but the ends of the jack bolts will grind into your floor a little bit. You also need to be prudent about how high you jack it up. Columns under compression will deflect abruptly, when either the load or the length gets too large. I would treat anything under 3/4" jack bolts like the pinch bar, and continually update the stacks of blocking as you raise the machine. That way, if anything goes wrong, the machine will be caught before it falls or tips very far.
 
Right in the front of the photo is a hole for bolting machine to floor.

Usually sized close for 5/8 threads.

Check hole size and drill out as needed to allow tapping for bolt.

Now use long all threaded high grade bolts to simply raise the machine carefull and slowly straight up...1/4 turn on each foot going arround it.

Place blocks or other spacers to support as you go.

The adjustable feet may have stud mount so tap to same size.

We lifted our 6800 pound L&S 6 inches to allow pallets under it this way.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk

Jeez.. all that to avoid using a heel bar in the pockets provided for that very purpose?

I guess I could see doing it for a 7k lb machine (although at that point I'd rather use toe jacks), but this is 3000 lbs - you could lift it with a straight pry bar and some blocking, or hell, even with a 2x4 if it didn't have any knots.

OP, don't overthink it - stick a lever under it and pry it up. There's no science to it.
 
Riggers bar and 2x6 scraps. Go slow and don't lift it more than you need to for the next block. Having a helper makes it go easier but a luxury I rarely have, wife isn't into this stuff.
 
Thank you guys for all your replies! The answer for me was "riggers bar", which is also called "pry lever bar". I will order one right now - life is awesome!
 
How do you plan on adjusting them once installed?

I use a rigging bar to adjust mine and have it sitting on shims

Sent from my 2PS64 using Tapatalk
 
I prefer a stair step pattern with 1-1/4" treads and 3/4" risers cut into 4 4x6 blocks. A lot less stuff slipping around than with individual small pieces when trying to lever up a heavy load, plus you don't need to worry about pushing a piece under the machine by accident.
 
I moved two mills and three lathes the last couple weeks. We could have used pinch bars and blocking to get it high enough to get skates under it. Instead we used a cheap Chinese toe lift jack. It saved a lot of work and, in my opinion, was safer.

Before raising the machine I suggest blocking it up high enough to get your fingers under it. Feel around below the screw holes. I think you will find there is no iron directly below the screw holes that would bear on your anti-vibration pads. You could tap out he screw holes. Remove the studs from he pads. Countersink the tops of the pads. Use large setscrews through the tapped holes. They would bear on the countersinks in the pads. As Tony said you can use the screws to raise the machine. Use temporary blocking (one corner at a time) to hold the machine up as you install the pad and run the screw down into the countersink.
 
With a mill you have a built in screw jack... cut a 2 x 4 of appropriate length to wedge under the table (ideally near to the Z screw as possible) and crank the table down on the lumber.

Once high enough place something in the "center of gravity" middle of the base and crank table back up. Rock machine down so that rear of machine is up off floor. If still not high enough place lumber under back, rinse and repeat procedure until it is high enough.

Of course a toe jack would be even easier.
 
With a mill you have a built in screw jack... cut a 2 x 4 of appropriate length to wedge under the table (ideally near to the Z screw as possible) and crank the table down on the lumber.

Once high enough place something in the "center of gravity" middle of the base and crank table back up. Rock machine down so that rear of machine is up off floor. If still not high enough place lumber under back, rinse and repeat procedure until it is high enough.

Of course a toe jack would be even easier.

I've done it that way before. On a " Bridgeport " I've put the timber under that bracket that carries the cross axis leadscrew. You're only lifting half the machine at any point. I'd be careful on anything much heavier than a " Bridgeport " though.

With a 3000 lbs machine I think you'd be OK with those rubber mounts. The manufacturers usually tell you what each individual mount will carry.

Regards Tyrone.
 
just curious- does one really want rubber feet under a mill?

Yeah mine sits on rubber pads on the corner of the base were the rasied feet are cast in on a bridgeporrt textron machines base, no - with out issue as does my lathe. IMHO the real risk is the feet the OP is proposing to use and using them in the bolt down holes, IMHO that puts them too far in and makes the machine dangerously tippy, most the old machines had bases and are designed around sitting on the rim of that base, the bolt down holes are for just that, bolting it down, putting feet there that far in under the machine and things are way to unstable for my liking.
 
I think people have failed to properly understand the OP's question. . if the machine is really floating 3/8" off the floor he can just increase the anti-grvity generator until it is high enough to attach the rubber pieces then turn it off slowly and allow the machine to settle down onto the new leveling feet.
I think it is very dangerous to tip the machine while the antigravity is on. A slight angle could cause the machine to tip over at a extreme angle with no warning.
Bill D
 
Best/cheapest source of shim wood is oak pallet slats. Thin, wide, rough and free.

Just did this recently on my Toolmaster. 5' bar was enough, as long as someone else was sliding in the wood. Don't use 2x material, as you won't be able to lift that high in each bite, and you want to limit how far it can fall if things go awry.
 
How do you plan on adjusting them once installed?
The feet are adjustable. If you rotate the bolt, the feet base would raise or lower against the rubber pad. They claim 2000 lbs of weight capacity each. The model is: Sunnex Machine Mounts 10002

I think you will find there is no iron directly below the screw holes that would bear on your anti-vibration pads.
That's what I ended up with.

With a mill you have a built in screw jack
On my mill the table would resist only to down force, but not to the lifting force. It will simly separate from the machine's base, at least that's what I read from other people.

IMHO the real risk is the feet the OP is proposing to use and using them in the bolt down holes, IMHO that puts them too far in and makes the machine dangerously tippy
I kind of realized that. The user's guide for the machine doesn't mention how to mount it. The machine was first made in 1956, may be they didn't concern about mounting those days. What are my options? I think about putting a steel strip or a C-channel underneath the mil, make it extend a few inches sideways out of the mill base and put rubber feet into the extensions.

I think people have failed to properly understand the OP's question. . if the machine is really floating 3/8" off the floor he can just increase the anti-grvity generator until it is high enough to attach the rubber pieces then turn it off slowly and allow the machine to settle down onto the new leveling feet.
Bill D
I tried that, but instead of machine lifting up, my entire house went down and now it's half buried underground. They should have mentioned that in the user manual, unfortunately it was in chinglish.
 
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I kind of realized that. The user's guide for the machine doesn't mention how to mount it. The machine was first made in 1956, may be they didn't concern about mounting those days. What are my options? I think about putting a steel strip or a C-channel underneath the mil, make it extend a few inches sideways out of the mill base and put rubber feet into the extensions.

Yeah if your going to put them in the end of the channels, no probs, should work well, just when this has come up before people have simply tapped the mounting holes and IMHO on a Bridgeport that's kinda iffy if you want to say do heavier jobs hung of the back of the table with the turret spun around to one side.

as to no mention in the manual from back then, gotta remember back then the default machine mounting style was to level and grout hence the base would very much end up supported right to its outer edges.
 








 
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