The Stovebolt Site Forums The Shop Area The Tool Chest Does thes exist? Or am I imagining it?

My dad told me a few days ago about a special impact driver his dad had. It was a large (1 inch drive) ratchet that, as you turned it, it would load a spring, then "fire," putting a hammer blow on whatever you were twisting on. Grandpa apparently got it from the National Guard, they used it to work on tanks (he used it on tractor wheels). My problem comes from me looking for it. Beyond the story, (and whatever farmer decided to dish out $1500 to buy it off my grandpa,) there is no evidence of this tool existing. Google believes that a mechanical, non-powered ratchet only comes in air or electric powered impact.

Has anyone here heard of a mechanical, hand operated impact wrench?

Yes, but nothing on that kind of scale. You would insert a bit of whatever size and set the impact to loosen or tighten then strike the back of the tool and several blows later the screw/bolt would come loose. Still available.

When I was in the service, the tank repair shop I ran had a torque multiplier wrench that was basically a gear reduction box with a lever that you'd put on the ground. Socket on the bolt, torque multiplier on that, then a ratchet or breaker bar turning the input of the torque multiplier. It was a 3/4 inch or 1 inch square drive, IIRC. And took the biggest mechanic in the shop to even carry it.
Here's' a similar item but more compact than I remember. Torque Multiplier Wrench
Here's something that works on that principle, but somewhat different in operation. Cheater Wrench
For a spring loaded impact thingy to work, you'd probably have to turn it backward to wind up the spring which would then release and drive a hammer against the part holding the socket. Not impossible to do mechanically, but kind of complicated and cumbersome, IMO.

You might be thinking of something like this
https://catalogue.facom.com/fi-en/c.../3-4-drive-dynapact-manual-impact-wrench

Not quite, my dad describes it as a cast rectangular housing, with a T knob on top (to set direction) and and a pipe handle. It really sounds like some souped up ratchet that hammered every 10 degrees or so of rotation. It certainly wasn't a torque multiplier (they cannot take any hammering) but it may have had some kind of planetary reduction.

I can build something like it, but why build, when i can possibly acquire?

What I linked to may not be same shape as what you remember but I think it functions as you describe. A manual impact wrench, offered in at least 3/4 and 1” drive if not others.

They are interesting tools to have in your collection, and "one can never have too many tools" but I'm wondering why you even need something like that, when a pneumatic or electric impact gun can do the trick.

The dynapact is promising, and may be what i get anyway, but i personally like the "all-in-one" approach; a ratchet that will hammer the nuts off anything I want. Though the dynapact says 60 degrees, versus my dad's claimed 10-15 degree (a nitpick, but something to consider if short throw is a factor), I hope that it can drive off anything I put it to, 737 ft lbs is a fair bit, but may not be enough, I'll have to look into that.

My primary use for it is to remove the lug nuts on my truck. 6 lug Budds request 500 ft lbs torque to install, and a blowout on the road leaves me SOL. I tried using a 3/4 ratchet with a 4 ft cheater, and I got nowhere. It would also come in handy on my backhoe and Allis Chalmers tractors, and any mower decks using a single mounting nut/bolt.

Mostly I want to know what to look out for, so I may get it for future use.

That cheater wrench looked like the ticket for lug nuts. If you didn't watch the video on that site I posted, it seemed like it wouldn't take that much effort to get a stubborn lug nut loose, although I don't know how tight those were on the demo video. But it's not an all-around tool like the Dynapact would be.

I have a 1/2" drive ratchet set that works as you described via an internal hammer spring. The socket extensions shafts are about 1-1/4" in diameter to prevent flexing when it hammers. I'll take a look at it next time I'm in the shop to see who made it. I carry it when I'm walking the junk yards.

Mike B

The OP's description sounds like a Swench. I think Curtiss Wright made them years ago. I have never seen one in the flesh. Search eBay for "swench" and you'll see quite a few examples. I'll stick with a cordless impact.

SimS

It does sounds like the Swench is what he might have been describing. They're still available new from Power Hawk Technologies, and I just saw one on eBay for $150.
Might be a handy field tool where now electric power or compressed air is available. I've had a few bolts that were too rusted to get loose with an impact wrench and needed the blue-tip wrench. Might have defeated one of the smaller Swench wrenches (rated at 500 ft-lb), too.

Yup, that's what I have, a Swench 1/2" drive set with Ratchet, Sockets, Extensions, Adapters and metal carrying case. It's a great tool and I always carry it when walking the junk yards!

Mike B