Upgrading Harbor Freight 20-ton Press to Air

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SteveHGraham
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by SteveHGraham »

The HF air jack also has a handle.
Every hard-fried egg began life sunny-side up.
spro
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by spro »

So that means it works like a two stage hydraulic pump? Hey, whatever Works is good.
chief
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by chief »

Liveaboard,
I added a HF 20 ton air over hyd jack to my press, and it has the standard jack handle style pump as well as the air system. I use that, as you suggested, for fine control.

Terry
spro
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by spro »

Right. There is feedback from what you are doing, looking at the pressure gage and moving things around because it can't be that tight. The worst thing with these type presses is misalignment. There is all that pressure and its going to do it but a race may not be a race anymore. Pressed at a slight angle and its over.
spro
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by spro »

Something else: Press accessories like stepped cones of various diameter. Some look like clutch alignment tools but they aren't aluminum. These are heavy solid discs and cones from OTC and many other great manufacturers. The screw may have blew but these are things to have.
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liveaboard
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by liveaboard »

I had a look for a second, high volume pump; the ones I found cost more than the rest of the press.
So I'll be wiggling the one handle as necessary.
Went to the post office; no seal has arrived.
grumble, grumble...
spro
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by spro »

Don't quit looking for the two stage pump. Like many things, too much pressure blows the frame or distorts things but that was then. The unit that did that, is detachable. One hydraulic hose and some bolts.
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by spro »

It's okay. I hope your seals have arrived so you continue with the press project. The one press is a bench press with a pressure gage but the pump is separate "power pack" which can be mounted anywhere. It is just fine.
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by spro »

BTW, I'm one of those guys who purchased the iron bed plates. So far so good but I stand at the side because the pump is at the side for one thing. The larger press has thick steel plates underneath the iron....but fracture could still happen.
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by spro »

Okay. Before somebody says it, here goes. I talk about alignment then how does he put iron plates on steel plates and expect perfect alignment? I don't. I check and reset along the way, it is easy. The further the ram is extended under pressure, it is distorting the frame in ways we don't see. Since it is longer extension it magnifies the inherent play which is already there. So when it gets crunchy or too much feedback, something needs attention and shift things. I could have faced off those iron plates. I could have made them very square and true to what purpose? I hear they are going to explode anyway.
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Re: Upgrading Harbor Freight 20-ton Press to Air

Post by spro »

Btw, old hacks like me save bearing races for a purpose. They may be torn up inside but accurate to height and very hard. One can see the imprint of these over time. What I mean is imprint into bed plates. I'm not throwing a bearing upon a rough surface, there is always something to space the work. The hard races do imprint.
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