Culver LFA Posted May 8, 2020 Report Posted May 8, 2020 Some of you may remember that I toyed with the idea of converting my M20F back to Johnson bar about a year ago. It was produced as a J-bar in December of ‘66, converted to electric for the first owner in ‘67, and stayed that way until the Coronavirus lockdown. The conversion back to j-bar went well, very straightforward operation and was a great opportunity to strip and repaint the control and gear pushrods, clean and lube all the rod ends so they are like new, and also super clean any oil and dirt from the underside floor. It was a really satisfying annual with gear conversion that stirred up lots of comments and questions from the airport drive by experts. I’m really enjoying the manual gear, it’s a big enough change that the airplane feels ‘new’ and exciting to me. Such a simple and wonderful design and the old girl dropped a few pounds as well. You all know what a Johnson bar looks like but I’ll post some pictures later because I’m really proud of the work. If anyone is interested in a complete conversion kit to electric gear, everything you need will be posting in the classified area soon! 11 Quote
cferr59 Posted May 8, 2020 Report Posted May 8, 2020 It would be nice to see your new shiny johnson, but welcome to the club! 1 Quote
gsxrpilot Posted May 8, 2020 Report Posted May 8, 2020 I almost wish that conversion was available for my 252. You gotta love a good Johnson bar 2 Quote
Shadrach Posted May 9, 2020 Report Posted May 9, 2020 52 minutes ago, gsxrpilot said: I almost wish that conversion was available for my 252. You gotta love a good Johnson bar I bet it wouldn’t be that tough to get to the DER approval. Would make for a very unique 252! 2 Quote
chriscalandro Posted May 9, 2020 Report Posted May 9, 2020 I have had a few opportunities to upgrade from my C, but at the end of the day the simplicity and the low maint. of the J-Bar came out on top. Quote
Hank Posted May 9, 2020 Report Posted May 9, 2020 1 hour ago, chriscalandro said: I have had a few opportunities to upgrade from my C, but at the end of the day the simplicity and the low maint. of the J-Bar came out on top. It works better for those without right shoulder issues. But the plane I found was electric anyway, it really wasn't a consideration. Since then, though, I've been glad to be electric. And my right shoulder surgery was 6 years before Mooney ownership. Quote
Kmac Posted May 9, 2020 Report Posted May 9, 2020 3 hours ago, Culver LFA said: Some of you may remember that I toyed with the idea of converting my M20F back to Johnson bar about a year ago. It was produced as a J-bar in December of ‘66, converted to electric for the first owner in ‘67, and stayed that way until the Coronavirus lockdown. The conversion back to j-bar went well, very straightforward operation and was a great opportunity to strip and repaint the control and gear pushrods, clean and lube all the rod ends so they are like new, and also super clean any oil and dirt from the underside floor. It was a really satisfying annual with gear conversion that stirred up lots of comments and questions from the airport drive by experts. I’m really enjoying the manual gear, it’s a big enough change that the airplane feels ‘new’ and exciting to me. Such a simple and wonderful design and the old girl dropped a few pounds as well. You all know what a Johnson bar looks like but I’ll post some pictures later because I’m really proud of the work. If anyone is interested in a complete conversion kit to electric gear, everything you need will be posting in the classified area soon! Would like this post twice if I could. Thanks for the write up. 2 Quote
Ross Taylor Posted May 9, 2020 Report Posted May 9, 2020 Like yours, our E came off the line and had the first factory test flight (and COA) issued with a Johnson bar...then got converted in less than 2 weeks. I'll not bother converting it back, after all this time, but it's the only thing on our plane that wasn't "ideal". I like the manual gear simplicity. I also like that there's no minimum speed limitation on raising it. I'll soon be adding an override button on ours, because sometimes I want to raise it before the speed sensor activates. Good for you - and I'll be watching for pics! Quote
carusoam Posted May 9, 2020 Report Posted May 9, 2020 Hi my name is Mooney, my pronouns are... Ross, There may be an adjustment on the airspeed switch you have... Any idea what speed it is requiring for raising the gear? Best regards, -a- Quote
Kmac Posted May 9, 2020 Report Posted May 9, 2020 When I was searching for my first Mooney a manual gear was a must on my list of wants. As soon as I would see an ad where one was converted to electric I would move on. I may have even passed on some with potential. If I look for another Mooney in the future I'll consider electric gear because of the information @Culver LFA provided. Looking forward to the pictures... Quote
cctsurf Posted May 9, 2020 Report Posted May 9, 2020 Gotta wonder what a reverse conversion would require on a plane originally built with electric gear...Say a late model F model...of course not one with a quadrant. Sadly, I believe early model Js were all quadrants... Quote
Culver LFA Posted May 9, 2020 Author Report Posted May 9, 2020 3 minutes ago, cctsurf said: Gotta wonder what a reverse conversion would require on a plane originally built with electric gear...Say a late model F model...of course not one with a quadrant. Sadly, I believe early model Js were all quadrants... First thing I would inspect is the fuselage tubing just below the nose gear hump, to make sure that the pivot points are there for the Johnson bar, the bellcrank for the electric gear is located about 5” aft of where the Johnson bar bellcrank goes. My airplane had both pivot bushings in place and it appeared that was from new, not added on at the conversion to electric. Maybe they are all that way. 1 Quote
Ross Taylor Posted May 9, 2020 Report Posted May 9, 2020 16 hours ago, carusoam said: Ross, There may be an adjustment on the airspeed switch you have... Any idea what speed it is requiring for raising the gear? Best regards, -a- I definitely think mine is too high. If I remember what I've read on this, it's supposed to be close to 80mph...but ours is closer to 90. When we're next behind the panel, I'll get that addressed (that's where the adjustment is, right? on the sensor behind the airspeed indicator?). At first, I thought we had a finicky squat switch and cold donuts...then discovered that the '66 Es don't have a squat switch. Quote
Richard Bronson Posted May 9, 2020 Report Posted May 9, 2020 When I owned the airplane, I had to have the switch adjusted several times. Coming out of Key West about 10 years ago the gear would not come up at any speed. I had it adjusted to about 70 MPH. I would bring the gear up pretty early... 1 Quote
Ross Taylor Posted May 9, 2020 Report Posted May 9, 2020 2 hours ago, Richard Bronson said: When I owned the airplane, I had to have the switch adjusted several times. Coming out of Key West about 10 years ago the gear would not come up at any speed. I had it adjusted to about 70 MPH. I would bring the gear up pretty early... Thank you, sir, for still watching over me! For those who don't know, we became stewards of our E from Mr. Bronson and he put a lot of love into it. It recently had the first annual in our hands and our A&P/IA (who also owns two Mooneys himself) was super impressed. I hope you are well - and please know that this aircraft is still loved and enjoying new adventures! 2 Quote
PT20J Posted May 10, 2020 Report Posted May 10, 2020 You know, the Johnson bar originally referred to the reverse lever on steam locomotives, supposedly colloquially named after an engineer at Baldwin Locomotive Works. Not to say it's a throwback, but .... I enjoyed it on the Ranger I used to check people out in at a club in San Jose, CA so many years ago. But, I like the little switch on my J Skip Quote
carusoam Posted May 10, 2020 Report Posted May 10, 2020 Skip, Did you write this? https://en.wikipedia.org/wiki/Johnson_bar_(vehicle) They even reference the M20... Many machines use a Johnson bar... But who is Mr. Johnson...? Best regards, -a- For real fun, see the limitations section of the Johnson bar... A reminder to not unlock the J-bar at cruise speeds...(or high steam pressures) https://en.wikipedia.org/wiki/Johnson_Bar_(locomotive) PP thoughts only, not a mechanic... Best regards, -a- Quote
N201MKTurbo Posted May 10, 2020 Report Posted May 10, 2020 Strange, I’ve been trying to completely understand the Walschaerts valve gear. And here you are talking about Johnson bars... Quote
Tcraft938 Posted May 10, 2020 Report Posted May 10, 2020 On 5/8/2020 at 7:00 PM, cferr59 said: It would be nice to see your new shiny johnson, but welcome to the club! If you show “your shiny new Johnson” you May have to run for President. Quote
PT20J Posted May 11, 2020 Report Posted May 11, 2020 19 hours ago, N201MKTurbo said: Strange, I’ve been trying to completely understand the Walschaerts valve gear. And here you are talking about Johnson bars... One of the keys to steam locomotive efficiency is setting the cutoff -- the point at which steam is no longer admitted to the cylinder. When starting from a standstill, there is a need for maximum torque and the steam is admitted for most of each power stroke (steam engine pistons are double acting so the steam pushes it both ways, and there are four power strokes per revolution). But at higher speeds, it is more efficient to admit steam for only a small portion of the stroke. The reverse lever controls the cutoff from full forward admission to no admission to full reverse admission and all points along the continuum between the forward and reverse extremes. The three main valve gears were the original Stephenson used on US locomotives in the 1800s, the Walshaert developed in Germany and widely adopted in the US and the later Baker. All three were progressive refinements to the difficulty of using a purely mechanical system to adjust valve timing. It's pretty interesting stuff. Skip 3 Quote
steingar Posted May 11, 2020 Report Posted May 11, 2020 Yeah, I'm an afficionado of the bar. Wouldn't even look at ones without. I've probably had more trouble with mine than most, and I still wouldn't trade it. Quote
N201MKTurbo Posted May 11, 2020 Report Posted May 11, 2020 1 hour ago, PT20J said: One of the keys to steam locomotive efficiency is setting the cutoff -- the point at which steam is no longer admitted to the cylinder. When starting from a standstill, there is a need for maximum torque and the steam is admitted for most of each power stroke (steam engine pistons are double acting so the steam pushes it both ways, and there are four power strokes per revolution). But at higher speeds, it is more efficient to admit steam for only a small portion of the stroke. The reverse lever controls the cutoff from full forward admission to no admission to full reverse admission and all points along the continuum between the forward and reverse extremes. The three main valve gears were the original Stephenson used on US locomotives in the 1800s, the Walshaert developed in Germany and widely adopted in the US and the later Baker. All three were progressive refinements to the difficulty of using a purely mechanical system to adjust valve timing. It's pretty interesting stuff. Skip I’m glad somebody gets it! The piston valve was very inefficient because admission cutoff also cutoff exhaust, which is not what you want. Im just trying to memorize the name of all the rods and bars, and be able to picture in my mind how they move. The expansion link and the radius bar were the hardest to wrap my head around. All that monkey motion to move a piston valve back and forth an inch or two. I actually found a site that did a mathematical analysis of every link. Quote
PT20J Posted May 11, 2020 Report Posted May 11, 2020 12 minutes ago, N201MKTurbo said: I’m glad somebody gets it! The piston valve was very inefficient because admission cutoff also cutoff exhaust, which is not what you want. Im just trying to memorize the name of all the rods and bars, and be able to picture in my mind how they move. The expansion link and the radius bar were the hardest to wrap my head around. All that monkey motion to move a piston valve back and forth an inch or two. I actually found a site that did a mathematical analysis of every link. It's kind of a mechanical analog computer. My wife says I'm enamored of archaic technology. That's why I volunteer at a museum with lots of old round engine airplanes and hang out around steam engines Skip Quote
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