DIY machine jack

I assume you're referring to one of the Porta-Power type hydraulic kits, with the spreader cylinder, an extension cylinder and various poles and attachments. These are pretty much essential kits to have if you deal with anything heavy even occasionally. Indeed they have attachments for the extension cylinder to use it as a toe lift, I had to use that attachment when my forklift crushed through the plywood I had run it on over gravel.

I made just such a gadget to level my spa, which I had made by a concrete septic tank manufacturer. It had settled a bit on one side. I carved a bit of the foam under it away to insert the edge of the hook. After jacking it up, I used a grout pump to pump grout into the resulting gap. The tank is a 6 foot OD cylinder of concrete 3 inches thick, so it weighs a few thousand pounds.

I recommend that you don't make the angles 90 degrees. You might want the edge under the tool to be a little higher than the welded edge. This will give it some grab, so it doesn't slide out when you lift. It will also apply the force further from the edge, avoiding damage. Similarly on the jack edge. A little angle down towards the jack will help it stay on the jack.

I just did the best weld I could with my 135 amp AC machine. As an amateur, that was not very good, but it held just fine.

I used 3/8" or 1/2" steel plate about 4-5 inches wide, IIRC, rather than the rod you suggest. I used a standard 3 ton automotive floor jack to lift it.

Hi John,

Here are the pictures of the machines:

-- Timur

Bob, that's a good point. The commercial units also have perforations on the toe, but I think that is not so critical as the slightly lower angle is.

Ok, I have 3.2mm 6013 rods and my machine is 250 amps, so that should be fine. The seller told me that this machine will even burn 6 mm rods, but I doubt it. Maybe it will do 5mm, I don't know...

I will also use a 45 degree endmill to create chamfers at the edges of the pieces to fill in the rod. For a 15 mm piece, what kind of chamfer do I need?

I have bought a 5 ton jack. It was really cheap, somethink like 30 dollars.

-- Timur

BTW, the lathe already has some feet installed, but these were installed incorrectly, so they will be removed first and will be installed correctly.

Make a frame like this and hang a two ton hoist on it. It is dismantled easily and portable and you can use it for lots of things in the future (car engines etc)

This is a Johnson bar:

handle is hardwood, about 50mm thick by 1.5 meters long. The steel plate on the end would be about 12mm thick by 100mm wide, perhaps

200mm long. The handle is sandwiched between the plate on top and another one below that holds the casters. The bent end is milled or forged into a wedge. Are there still blacksmiths in Turkey?

It doesn't need wheels if you are only lifting. They allow a crew to move the load with one J-bar in each corner. It still needs a plate on the bottom to spread out the force on the handle, though

I've picked up one end of a ~2000 Kg machine with one when I was younger and lighter, ~70Kg. Position a wedge next to the machine and have a stick or broom handy to push the wedge under it when you lift.

Be Careful - if you lose control the handle can give you a bad whack in the chin.

jsw

What's that Lassie? You say that Gunner Asch fell down the old sci.engr.joining.welding mine and will die if we don't mount a rescue by Sat, 14 Nov 2009 05:20:11 -0800:

I must second this. Bricks, masonry blocks etc. can and will fail all at once, without any warning, with bad results.

Noted, and thanks. --Glenn Lyford

We actually like you Glenn..and would wish you a long and happy life.

Gunner

"Aren't cats Libertarian? They just want to be left alone. I think our dog is a Democrat, as he is always looking for a handout" Unknown Usnet Poster

Heh, heh, I'm pretty sure my dog is a liberal - he has no balls. Keyton

When I was a millwright we used rol-a-lifts to move lathes and mills. With a Johnson bar You tip the machine up enough to insert the forks, do likewise on the other side, strap the two together and jack them up. You now have your machine on wheels in case you want to relocate it. you may not want to buy two of these but at least you can get some ideas from the pictures if you're building some devices.

Engineman

Excellent equipment.

I dont see very many of these in California..most folks simply hire riggers and have them move Stuff with fork lifts..but I can Definately see the utility value of these devices.

Gunner

"Aren't cats Libertarian? They just want to be left alone. I think our dog is a Democrat, as he is always looking for a handout" Unknown Usnet Poster

Heh, heh, I'm pretty sure my dog is a liberal - he has no balls. Keyton

So what happened exactly, what kind of bricks were they and how did they fail?

i

The local train men - yea the ones that pick up trains and train wrecks - a retired one is a personal friend.

They use wood - big blocks of wood. And long levers and brute.

The wood is used as artificial rails allowing the wheel flange to dig in and stabilize. It was 'walked' back on top of the rails...

Some of the stories are hair raising from what they went through.

Brick and concrete bricks have a certain pressure design level.

Exotic designs have to be done when stacking high brick walls. They begin to compress towards a shatter point.

Our lodge downtown was over 8' in base wall brick. It was a 3 story. (still lasts - we moved.)

Mart>> NEVER use Brick!! Evernevernotevenalittleevernever!!

3 hole cinder blocks with a 2x6 on top of them. As I recall..one of them (2x6 split)..the metal contacted the cinder block and it instantly collapsed, taking out 2 others at the moment of "bang" on the floor.

It crushed his chest and evidently as he started...he looked upwards and took the bottom of the transmission directly in the center of his forehead...which then crushed his skull and largely turned it into a flat wad on the floor. A flattened ball with all the cottage cheeze squeezed out of it.

Not the worst way to die..it was nearly instant. Best as I and the coroner could figure. But it was ugly. His wife took to the bottle and was years crawling out of it.

Shrug. Not one of the best ways to go..or one of the worst. Ive seen far better..and far worse. But..he was only 27, with 2 kids and a very lovely and loving wife.

Gunner

"Aren't cats Libertarian? They just want to be left alone. I think our dog is a Democrat, as he is always looking for a handout" Unknown Usnet Poster

Heh, heh, I'm pretty sure my dog is a liberal - he has no balls. Keyton

Many thanks for all replies.

I really want to build an engine hoist with 2 ton capacity so that it can be used for this job and any other moving jobs, like the milling vise, the rotary table etc, but this will likely take a long time to plan and finish. So I think I will try building the hook from 15 mm thick mild steel and then will use it with the bottle jack. I drew up the design, it's available here:

Any critique or suggestions for improvements appreciated :) I would love to hear any comments about the following:

- The hook is currently attached to the top of the bottle jack, using the extension rod that is screwed into the piston. Do you think a side rail is necessary for the hook to slide up and down?

- I want to weld the bottle jack to the base. The bottle jack bottom is cast iron and the base is mild steel. I have read that nickel rod or low carbon rod needs to be used for this, but my concern is that the bottle will deform from the heat and will fail to retain the hydraulic oil in it. Can this happen that heat deformation will cause the cylinder and the piston and the hydraulic pump loose their tight tolerances?

(...)

Yes definitely. You don't want to cause the piston to bend or stick in the cylinder due to side loading. The coupling between the top of the piston and your hook should allow a few thousanths of 'flex' because you want the side force to travel through the frame, not through the piston and cylinder.

I expect you could put a wet rag in the cylinder to keep it relatively cool. It is critical that the welding be done with the piston completely separated from the body of the jack. You don't want to convert the jack into a steam boiler!

There are experts here that can help.

--Winston

Ok, I can see now how the side force can cause the hook to dislodge. I have revised the design so that it includes the rails as well. For completeness, I am including it here as well:

I think I will try heating the cast base of the bottle jack to 100 degrees celsius using a hot air gun and then I will put small tacks around the base and let it cool in between. Let's see how it works out ...