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A Man Who Has Nothing In Particular To Recommend Him Discusses All Sorts of Subjects at Random as Though He Knew Everything

Hydraulic To Lift, Mechanical To Support

OK, there’s another piece of equipment we’re going to be using, and it’s fraught with peril. It’s not a sawmill with all the guards removed or anything, but a little caution will go a long way with it. We’re going to buy some bottle jacks.

Bottle jacks are cheap, and they’re very powerful. Their lift ratings are way beyond anything from our screw jack calculations from yesterday. I bought a handful of 10-ton bottle jacks to help with the process. You could, too, if you were lifting up your own crappy abandoned Victorian dustcatcher at the edge of the map. But I promised to lay a Golden Rule for house jacking on you, and it involves bottle jacks, and screw jacks, and shores, and any other version of things to prop up a house. Here goes:

Use hydraulic jacks to lift, use mechanical jacks to support. To shorten it even more: hydraulic to lift, mechanical to support.

This is tres importante, people. Hydraulic jacks like bottle jacks are way, way more powerful than almost any screw jacks, but they have two fatal flaws that can be fatal to you, too. You just can’t rely on hydraulic jacks to keep holding things over your head for very long. Firstly, when a hydraulic jack fails, it fails utterly. If it blows out a seal, the plunger in the jack plunges immediately under its load. Bottle jacks don’t often fail, but then again, you don’t die very often, either. Once is generally enough for both to happen. That’s why smart mechanics might use a hydraulic jack to raise a car, but they won’t work under it until they place stanchions (a form of shore) under the frame. Hydraulic to lift, mechanical to support.

Secondly, even if the hydraulic jack doesn’t fail internally, it can tip over. It’s a hinky little process to align a solid base under a bottle jack, a metal plate on top of its plunger to spread the force over a larger area, and then keep the jack both plumb (level, except vertically) and centered under the weight it’s lifting, which by the way is moving around. Your house and the ground want to spit that bottle jack out sideways like a watermelon seed.

There’s another problem with really powerful jacks. They can lift 20,000 pounds each. So what? your house is not a dump truck. There’s no place to put a jack on your house to lift the whole thing, so don’t bother looking in your house’s owner’s manual to find the jacking location like you do with your Audi. If you put a 10-ton jack under a spot in your house and start pumping the handle, you’ll just puncture a hole in whatever you’re trying to lift, or whatever the jack is sitting on. Your house is more like a tent than a solid structure, remember?

Now here’s another handy tip: Go to flea markets. Look for something called a railroad jack. It might be called a trumpet jack, or something similar. It’s a trumpet-shaped, cast iron blob with a steel screw and head coming out of the top of it. A new one looks like this:

But you don’t want a new one. A new one can lift 20 tons, but it costs $200. Farg that noise. Go to flea markets and poke around, and you can find them for twenty bucks or so. Antique-type places just think they’re vaguely industrial knick-knacks, suitable for conversion into the center leg on a Fire Island coffee table. But no matter how old a railroad jack is, it will still work, and they’re absolute beasts for picking things up. I bought one to go with my stunningly curated collection of bottle jacks.

So, despite our Golden Rule, we could just use our screw jacks to lift the house, and skip hydraulic jacks altogether. They’re very unlikely to fail catastrophically, and they act as shores the moment you stop turning the screw. Why do we need bottle jacks, anyway, you ask?

Because we’re lazy. Indolent, almost. I have to lift a house, but I don’t want to lift a house. I don’t want to die while lifting the house, or end up wearing a truss for the rest of my life, either. But you try turning the screw on a screw jack while a house is sitting on it. The sales brochure is accurate. It says it’s possible. It didn’t say it wasn’t hard.

And remember, you have to turn a whole bunch of them, basically all at the same time, if you want to lift a house properly. On a good day, when the teenager is awake before noon, we’re just two people working. So we use hydraulic jacks to lift a little, and then spin the screw jacks like crazy, with the pressure mostly taken off them, and repeat, over and over, while the plaster flies off the walls upstairs. Because we’re lazy, and in a hurry, remember?

The advice you always get, to only raise your house 1/8″ a day, is for people who care if the plaster in their house hops off the wall. They must live in a nice house, to care about something like that. Me? I bought a house that cost less than a motorcycle. There’s no way I can make it worse, so what me worry? The plaster in my house will hop off the wall whether I jack the house up or not. Forcing it to immediately will save me having to demolish it later anyway.

Enough of all this theory! Tomorrow, let’s get physical.

2 Responses

  1. Great to see ya back, homie
    When does Unorganized Hancock: The Making of the Band come out?
    Left Coast Dave

  2. Dave! Tell an interfriend that Sippican Cottage is back.

    Unorganized Hancock got more irregular when The Heir got all adulty and moved out, but they will return, too.

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