Good evening, all! I may need to install a bunch of quartz fit-up movements in former Hahl pneumatic clocks in a public building (The Hahl system is almost certainly irreparable). Would like to use radio-controlled movements so that they won't have to reset time in the spring and fall, and so that they'll stay accurate. (Some of these clocks require tall ladders to reach, so nobody wants to have to get up there any more often than absolutely necessary.) Any ideas on what's the best radio-controlled quartz fit-up? Need something reliable, ideally with long battery life. Fortunately, none of these clocks uses a second hand, so no worries about that. And, largest hands are no more than about 12 inches long, so although high torque might be desirable, we can probably balance the hands to help the torque situation as well. Thanks in advance for your help! Best regards! Tim Orr
Attention Moderator: It has been suggested to me that this post might attract more response if it were in a more general category. Would you agree to move it there, or should we leave it where it is? Thanks! Best regards! Tim Orr
I doubt it would attract any more response in any other forum, Tim. There is a fellow who advertises in the bulletin looking for these clocks. He might be able to help you resurrect these clocks. Look for Larry Kruzel. I would like to think anything is repairable by the right person.
Here is one source for battery radio movements. This company sells commercial master clock systems and parts. They also sell a battery booster pack. Nice for hard to reach clocks. Lets you go several years between battery changes. I've purchased master clocks and various replacement movements from them. I've never had any problems. http://www.american-time.com/
Good evening, Luke! Thanks! I'll look at their stuff. The Hahl system is very unlikely to be brought back for our project. Several of the Hahl clocks have been removed and cannot any longer be found. The facility reports that the pneumatic lines were cut during construction many years ago, and they don't want to try to find and repair them. Plus, this is a working courthouse, and the Hahl system is extremely difficult to reset for spring and fall time changes. We can get the master running again - for show - but the feeling is that the secondary clocks need to be something more reliable. Alas, most of what I'm seeing for quartz clocks and radio-controlled clocks looks like pretty cheap plastic stuff. I suppose it may be more reliable than it looks. I like the auxiliary battery packs for extended battery life that American Time offers. Ironically, in its day, the Hahl system was considered to be MORE reliable than electrical clocks. Batteries and electrical systems were considered by Hahl to be much more unreliable than compressed air. Best regards! Tim Orr
Good luck, Tim. You won't find much that isn't made in China, with at best a 10 year life expectancy.
I've been kicking around the possibility of picking up a Hahl's slave, but I like my clocks to work as designed. One thought I've had to bring these back to life is to use a fish tank air pump as a pressure source. For control, I'm thinking that a self-winding impulse driver like a Piexx or one of Ken's winders could drive a Mercedes vacuum switchover valve. The switchover valve uses a 12 volt signal to switch vacuum between two paths, but could just as easily control air pressure. My question is, what pressure and pulse width would be required for a Hahl's slave?
Good afternoon! While I can't tell you the pulse width exactly, I can give you what Hahl had to say about the pressure: In an advertising piece, they said that the pressure is 1 inch of water. That works out to about 0.6 ounces, so it's not a lot. I do not know how much each slave movement requires in terms of volume. An original Hahl "bladder" looks a bit like a small "penny" balloon. Some people have successfully made bladders using fingers cut from rubber gloves. Of course, the size and stiffness of the rubber would affect the volume and pressure required. The volume is what amounts to the "amperage" of the system, while the pressure is the "voltage." And, a "system" of Hahl slaves would need both volume and pressure determined by how many slaves there were and the length of the run from the master to them. The advertising does say that Hahl used 1/4-inch iron pipe for the compressed air, and that is what we saw when we worked on the one here in Colorado. As to pulse width, I'm not sure. The Hahl we worked on cycled at probably considerably less than a second. That's one of those things you might be able to adjust by trial and error. By the way, our project eventually disclosed three slave clocks that were still connected to the master with intact plumbing. Two still had serviceable bladders, and a third was being adapted for the "rubber glove finger" type bladder by maintenance workers when we left it. The missing slaves were located in a clock repair shop nearby (where they had been sitting for years) but I do not know if any attempt has been made to re-install them. They declined to go with quartz fit-ups, even of the "atomic" type, and where necessary, simply installed modern quartz clocks. The "spring forward/fall back" situation remains an issue with the Hahl system. We made the obvious suggestion of stopping the master clock for an hour in the fall, and also suggested stopping it for 11 hours in the spring, since there's no way to "manually" advance the slaves easily. It's a public building (not occupied for more than about 10 hours a day), so we suggested the maintenance people could either stop the master in two separate durations, adding up to 11 hours, or they could shut it down for 22 hours, by stopping it on one day and then restarting it at the 22nd hour on the next. Good luck! Best regards! Tim Orr
Good afternoon! By the way, it looks as though your Hahl mechanism might be using a sort of piston-like actuator. If that's the case, it might be possible to repair it or recreate it. What puzzles me is how you'd avoid losing air. Might not matter with an aquarium pump supply, but I wonder how that worked with the original Hahl bellows supply system. Best regards! Tim Orr
