We’ve got a big granite chimney top assembly coming from the stone yard. To get it in place, we’ll need a crane.
The whole thing is 39 inches wide by about 14 feet long, and is made up of 10 pieces of precision-sawn granite. Three lower slabs, each about 39 x 55 inches by 3-3/8 thick, weigh about 690 pounds apiece. Four columns, each 4-1/4 x 39 x 18 inches tall, weigh 276 pounds per. The top slabs, three of them, at 4-1/4 thick, each weigh about 860 pounds.
We will need to be careful. Total weight of all the granite parts is a little over 5,700 pounds.
I’ve been doodling up something on CAD, a lifting cradle assembly, made up of some steel angle, bar, and some 2×4 spreaders. Short pieces of 3 x 3 angle make up the “edge hooks” that will allow us to place the large slabs without bottom interference.
It is shown on the attached pic. The crossbars shown, two of them, are 3/8 x 2-1/2 bar stock, and will permit slings to grab the whole thing by wrapping below the “ear” ends. You can see the 2×4 spreaders in the pic, lagscrewed in place through the bars. The crossbars flip over and mount to the clips in the lower set of clip holes to handle the thinner bottom slabs.
We may be able to rent or borrow something to do these lifts from a local granite shop, but maybe not. If not, we need to make something up.
Is there an easier way to do this? Slinging it plain would mean we would have to block up the lower slabs off their landings, in order to get the slings out. Lifting one end then the other, to get the blocks out, seems tough to me.
Comments? Suggestions?
Gene Davis, Davis Housewrights, Inc., Lake Placid, NY
Replies
I've hired a crane a few times to move stuff. He brings a couple of big job boxes full of tricks--slings, spreader bars, etc.-- and wants to do it his way, which is usually quite smart and efficient.
Wouldn't mind seeing a pic of all that assembled. You say it's going up on the roof??
use slings , land it on blocks of ice
Good idea! You've done this? What if my 700 pound block turns into an ice crusher?Gene Davis, Davis Housewrights, Inc., Lake Placid, NY
No, haven't done it myself. But, I do know that's how they set the glass panels in the Monterey Bay Equarium (sp?).
Let's see if this photo copies through so you can see it.
View Image
The stone chimney top arrangement, three sections across the bottom, the center one with the flue hole, four upright "columns," and the three-section top can all be seen. This is the prototype house in Vermont. Ours will be a copy, but we're losing the standing seam steel roof. Client didn't want to go the thirty grand upgrade over architectural shingles.Gene Davis, Davis Housewrights, Inc., Lake Placid, NY
Thirty grand MORE for the metal roof? More than what? Ouch, I wouldn't either.
I don't see why you can't sling the pieces up there as usual and then use crowbars to pick up the corners and get the slings out. None of those pieces is that heavy, at least to a large crowbar or rock bar. I assume you are going to scaffold the thing to working height anyway, so it shouldn't be that hard.
The ice... interesting idea... what's to stop a piece from just sliding off onto your toes?
The ice... interesting idea... what's to stop a piece from just sliding off onto your toes?
Pushing hard enough to make sure it slides the other way?
Joe H
I'm not too sure if this would work but basically how the ice would work is something like this. Use 2x4s nailed together and placed on the corners of the chimmney (sp?) with pipe clamps (make sure that the 2x4s extended above the chimmney). Place four blocks of ice on each corner. Inside the blocks of ice, set tie wire so that you can tie the ice to the 2x4s, so they don't slip off before you get the granite slab on. Place the granite on top of the ice, come back in two hours, cut off the tie wire, etc.
bump
Scratch your head a little and try to recall if you have any old connections in the commercial building construction business.
There are devices for placing large granite and marble panels on large buildings. The granite supplier might be able to give you a clue.
I've been looking. Tomorrow we'll see what a guy we know that has a granite fab shop has for gear we might rent or borrow.
My crane guy doesn't have gear this specific, but he is a capable welder and fabricator, and can make this up if needed.
Googling all over the web for any kind of "granite lifting," "stone hoisting," and all possible combinations of search words, all I have been seeing is tongs that do the grabbing from top edges, or suction cup lifters for polished stone work.
We aren't lifting from the edge, with the parts upright. We must pick these up by catching a relatively narrow area of the bottom edges. Sort of like handling large sidewalk sections.
In the industrial world, there are lots of heavy tong lifter items available, like for handling blooms, ingots, and slabs in steel and hot strip mills. Way too huge for what we are doing here.Gene Davis, Davis Housewrights, Inc., Lake Placid, NY
Make the slabs suck helium...poof, yer up. Spheramid Enterprises Architectural Woodworks
You think that's funny? Watch THIS!...I can only do it once tho'
Standard steel channel iron
5" Web, 9.0lb/ft, 1.885 flange width, .325metal thickness
5.35" clear between flanges
1.56" flange depth
2 at 72" long. Drill 2 9/16" holes just inside each flange, 28" each side of center of length. 4 pieces of 1/2" allthread 48" long. 6 1/2" channel outside of allthread to hook your slings around.
Take two more pieces of channel, weld a plate from flange to flange across one end, weld an ear plate across the back of the web to run the all thread thru. Cut a "hook" hole in the other end of the channel thru the web.
SamT
Havine a hard time speeling today
Edited 8/7/2005 5:02 pm ET by SamT
Edited 8/7/2005 5:06 pm ET by SamT
Why not let the crane guys handle the whole thing? They probably have the necessary equipment - and experience - to do the job. I also doubt if they would want to use a homeowner designed lifting cradle unless you sign a liability waiver. - lol
I built this set of stairs from 2x4x8" granite blocks. I got a couple pieces of angle iron and welded up a scissor assembly that applys side pressure with the weight of the blocks. Kind of what they use to move Jersey barriers.
I set them in place with a backhoe
Sorry for the size of the file
Edited 8/9/2005 10:34 am ET by maverick