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View Full Version : Webster I.C. engine redesigned as "Hit and Miss" engine



brian Rupnow
08-25-2010, 06:53 PM
Last year, I built a Webster I.C. engine from plans that I downloaded off the internet. http://bbs.homeshopmachinist.net/showthread.php?t=41092&highlight=webster They are a great set of plans, and I am most impressed with the engine. I haven't machined much lately. Its summertime, and the hotrod cruise/show season is in full swing, and my (other) hobby, a 1931 model A roadster pickup has been filling my spare time. BUT----I 'bin thinkin'------
I think hit and miss engines are kinda neat. I built the Chuck Fellows hit and miss steam engine, and it performed well. Once I have built an engine, worked out the "bugs", and have it running well, its just not that interesting anymore. (after you've showed your wife, your kids, your grandkids, and any unsuspecting friends or neighbours that drop by---)
I've been looking at the Webster, and thinking---The thing that makes a hit and miss engine hit and miss is a function of some type of centifugal governor energizing a mechanism to hold the exhaust valve of its seat at high RPMs untill the engine slows down, then the exhaust valve is allowed to seat once more and the engine fires again untill the RPMs pick back up again.
Now if I was to move the gas tank, and run a jackshaft in a set of pillow blocks in the spot where the gas tank now occupies, and drive it with a chain drive, and the jackshaft had a set of bob-weights on it and a lever---and the exhaust valve lifter is right there close at hand---Hmmmmm----Food for thought----
http://i307.photobucket.com/albums/nn294/BrianRupnow/gastankinstalled004.jpg

brian Rupnow
08-25-2010, 06:54 PM
I'm going to do it!!! I checked today, and I can move the outboard bearing support over about half an inch. This will give me enough room to take a peice of 4" diameter brass or steel x 1 1/4" wide, hog out one side to 3.75 dia. x 0.75 counterbore, drill a 3/8" clearance hole on center, and slide it right over the existing flywheel and screw it to the face of the existing flywheel. This lets me keep the same crankshaft with no changes. That should give ample weight for the engine to keep rotating in a "open valve" state. I will have to machine a clearance pocket right below the flywheel to let me go from the existing 3 3/4" flywheel to the larger 4" diameter. I just finished building the 3 ball governor----I'm excited about this!!!

brian Rupnow
08-25-2010, 06:55 PM
School me, my brothers---Do you think it falls into the world of possibility to drive a govenor on a hit and miss gasoline engine with an o-ring drive belt? It works very succesfully on my twin horizontal steam engine, but when it "fires" there is nowheres near the same blast of torque that you get from an I.C. engine. Now, methinks this could go two ways. First way, that sudden blast of torque when the engine fires is sure to make the drive pulley slip a little bit in the o-ring belt.--However, it will probably catch up fairly quickly, and speed the governor up enough to lift the exhaust valve and slow the engine down. Second way---those neoprene o-rings are very elastic. I'm not sure what the result of that will be, but I think it will be the same as the First case---the o-ring will stretch elastically during the power stroke, then quickly "unstretch" during the exhaust, intake, and compression cycle. The net result will be a bit of lag from when the engine "hits" untill it begins to "miss". I have spent some time today studying the "silver Angel" engine, which has a most unique vertical camshaft, driven off a horizontal crankshaft, thru a set of 90 degree bevel gears. The flyball governor is attached to the camshaft. This makes me think that "all things being equal" the flyball govenor should rotate at 1/2 the speed of the crankshaft, thus a 1:2 ratio on the pulleys. I know in my heart that I SHOULD be using a gear drive to turn the flyball governor on my engine, however the configuration of my Webster doesn't lend itself very well to doing that. It seems to me that in the dark recesses of my memory, I have seen "full scale" hit and miss engines on which the flyball governors were belt driven, but I could be making that up-----. I guess that if the belt broke, one could be faced with a "run away" engine. Thinking---thinking----

brian Rupnow
08-25-2010, 06:55 PM
I know it sounds trite but---Size isn't everything---The valve spring on my webster engine which holds the exhaust valve closed is a very fine spring, only about 0.020" wire diameter. The attached images are of a "Silver Angel" i.c. engine with a 3/4" bore and stroke, similar in size to the Webster. It has large balls on it---probably 5/8" or larger. I know that with the governor I just built, it takes very little "spin" to make the balls fly out---but then again, the spring on the governor stempost is a very lightweight spring as well. This engine has a very unique vertical camshaft---and the cam is the round silver disc at the top of the vertical shaft. From remarks I have read by people who built this engine, the governor works very well, and since it is part of the "cam shaft", it would be rotating at 1/2 the speed of the crankshaft. One of the advantages that I see in driving the governor with a belt instead of a set of gears is that if the speed of the governors is to great or to little to be effective, it is a simple matter to change a pulley size. These neoprene o-rings will stretch to accomodate different pulley sizes, and have a relatively high coefficient of friction.
http://i307.photobucket.com/albums/nn294/BrianRupnow/SILVERANGELFLYBALLGOVENOR-2-1.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/SILVERANGELFLYBALLGOVENOR-1.jpg

brian Rupnow
08-25-2010, 06:56 PM
It begins---The first thing I have to do is change the flywheel weight on my Webster engine to be MUCH heavier. This is so that when the engine "misses" it will continue to rotate instead of quickly stopping as it currently does with its aluminum flywheel. I don't want to change the basic character of my engine. This is almost the ONLY change to the engine itself. I don't want to mess with the integrity of my current flywheel, because it has the one timing gear mounted in the side of the hub, and is pinned to the crankshaft with a pair of 3/32" diameter dowel pins. By doing things this way, I only have to move the outboard bearing support over a bit to make room for the new flywheel addition (This requires two new holes to be drilled in the baseplate.) The current flywheel is 3.75" diameter and the height of the crankshaft centerline is 2" above the baseplate. This will allow the outer diameter of the new flywheel "addition" to be 3 7/8" which will give me a rim 1/16" thick all around the original flywheel and still clear the base by 1/16". I will drill and tap the side of the old flywheel 1/4"-20 in 3 locations, and drill c'bored matching holes in the face of the new addition to bolt it to the existing flywheel. I REALLY would like to make this new flywheel addition from brass and polish it, but I'm afraid a peice of brass that big will cost a fortune. Steel would work as well, but it would be a pig to machine a c'bore that big in the side of it.--Of course it would be much, much cheaper, and I could paint it----
http://i307.photobucket.com/albums/nn294/BrianRupnow/WEBSTERENGINEREDESIGNEDFORGOVERNOR.jpg

brian Rupnow
08-25-2010, 06:58 PM
So---We're at the point of no return. I went uptown to one of my steel suppliers this morning and spent half the Rupnow fortune (actually $70) on a big old chunk of brass, 4" diameter x 2" thick. This will become the new heavier flywheel addition for the hit and miss Webster.
http://i307.photobucket.com/albums/nn294/BrianRupnow/BRASSFORLARGERFLYWHEEL002.jpg

brian Rupnow
08-25-2010, 06:58 PM
The bandsaw kept trying to rip the chunk of brass out of my hands, so I walked it out to the big old power hacksaw that I built about 40 years ago. Its sitting out there in the garage now chewing away---Makes a Hell of a racket, but the wifes at work so thats okay.
http://i307.photobucket.com/albums/nn294/BrianRupnow/sawingoneoff002.jpg

brian Rupnow
08-25-2010, 06:59 PM
Well, that went very fine!!! I even have a peice about 7/16" thick left over. The new brass flywheel fits snugly over the existing flywheel and makes an incredible weight difference. Tomorrow I will polish the brass to a mirror finish and put the Webster back together and see what difference it makes to its "coasting" ability.
http://i307.photobucket.com/albums/nn294/BrianRupnow/newbrassflywheel002.jpg

brian Rupnow
08-25-2010, 06:59 PM
Now THIS is a flywheel!!!! It certainly weighs a heck of a lot more than the original did. I always have this morbid fear that once I have taken a well running engine apart to modify it, that it never may run again. I hope this time proves me wrong. Now I'm off to the garage to test fire this beast!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/newflywheelinstalled002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/newflywheelinstalled001.jpg

brian Rupnow
08-25-2010, 07:02 PM
Hah---No worries! Runs like a champion. Good Lord, will it ever idle slowly now. And at about 1/4 throttle, if I shut off the ignition switch that new flywheel has enough momentum to turn the cranks shaft 5 to 7 times before all motion stops. If I reach in with my long screwdriver and hold the exhaust valve from closing, the engine will miss for 3 or 4 cycles, then if I let the exhaust valve close, it fires again and keeps on Running smoothly. This is very encouraging. Next thing required will be some more in depth design work to set up the flyball governor properly.

brian Rupnow
08-25-2010, 07:02 PM
And here is a short video of it running with the new flywheel. this is a new video---I spent an hour on the phone with Cannon and hopefully got the problems with my camera sorted out.
http://i307.photobucket.com/albums/nn294/BrianRupnow/th_websterrunningwithlargebrassflywheel.jpg (http://s307.photobucket.com/albums/nn294/BrianRupnow/?action=view&current=websterrunningwithlargebrassflywheel.mp4)

brian Rupnow
08-25-2010, 07:04 PM
I went and picked up my bevel gears yesterday, and surprise, surprise---The ones they got in were not the ones I ordered.--Thats okay, I can redesign to accomodate that. Now I believe Chuck and Mr Britnell, who have both told me that I don't want to hold the exhaust valve open gradually. I want to prop it open all at once. Therefore I have redesigned the linkages to slide a steel "slider block" under the business end of the rocker arm when the engine reaches the RPM at which I want it to start missing.
http://i307.photobucket.com/albums/nn294/BrianRupnow/WEBSTERENGINEREDESIGNEDFORGOVERNOR-2.jpg

brian Rupnow
08-25-2010, 07:04 PM
Some encouraging experimentation---I measured and found that when my exhaust valve is at maximum lift, I have 0.419" clearance between the underside of the rocker arm and the aluminum base. I made up a peice of aluminum bar 0.417" thick. I ran the engine at mid range RPM and slowly advanced my peice of aluminum untill it was riding against the side of the rocker arm. It only took a very light push to get under the rocker arm, and my engine immediately stopped firing and began to coast. I pulled the peice of 0.417 aluminum away (it took very little effort) and the engine immediately began to fire again. This exactly replicates what will happen with the "red slider" in the drawing above.

brian Rupnow
08-25-2010, 07:05 PM
And now you know how I spent MY afternoon!!! Its not finished yet, but you can see the detail of it laying underneath. That is the main frame for the 3 ball governor when I get it mounted on the Webster.
http://i307.photobucket.com/albums/nn294/BrianRupnow/GOVERNORFRAMEANDGEARS001.jpg

brian Rupnow
08-25-2010, 07:06 PM
And of course, I had to make a test block to mount my new bevel gears on to check and make sure the center distances in the catalogue were correct.---and they were bang on!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/GOVERNORFRAMEANDGEARS002.jpg

brian Rupnow
08-25-2010, 07:07 PM
Today it was back to more machining and some trial assembly on the governor frame.---I'm getting there!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/ASSEMBLYPICTURE001.jpg

brian Rupnow
08-25-2010, 07:07 PM
The bottom yoke on this flyball governor keeps evolving. Originally, I built it to move a pivot arm with a 3/16" brass pin in the slot. Then as I got a bit deeper into using it to work on my Webster engine, I decided it should have a pair of bearings in there instead to help take the load and run friction free. This afternoon I machined a peice of 1018 mild steel with a slot just large enough to accept 1/2" o.d. ball bearings, and press fitted the original lower yoke into it, along with some of my favourite 638 Loctite. Both peices were reamed to 3/16" diameter, then I inserted a shaft after applying the loctite to keep everything lined up true. I'll wait 24 hours for the Loctite to cure, then tap the shaft out and re-ream the assembly.
http://i307.photobucket.com/albums/nn294/BrianRupnow/BOTTOMYOKEEVOLVING003.jpg

brian Rupnow
08-25-2010, 07:08 PM
Sometimes I outsmart myself!!!---In that last picture I posted, the diameter on the extreme right of the lower yoke is supposed to be a seperate peice, with a set screw in it. I knew that!!! Anyways, I came down to me shop this morning and thought--"Hey---I could combine those two peices and make it all in one." It wasn't untill after I had machined it and posted it that I realized it can't be all one peice. Oh well, nothing damaged except my pride. I'll stick it back in the lathe tomorrow and machine the offending lump off.
http://i307.photobucket.com/albums/nn294/BrianRupnow/3BALLGOVSETUPFORBALLBRGYOKE-3.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/3BALLGOVSETUPFORBALLBRGYOKE--BALLSIN.jpg

brian Rupnow
08-25-2010, 07:09 PM
I have been thrashing away today at the fitment of all the parts, correcting the boo boo I made on the lower yoke, and making the lever with the ball bearings on it that rides in the yoke. Everything is going together very well, only a couple of levers left to make. No one in Barrie carries #5-40 set screws, so I have ordered a box of 100 that should be here in a couple of days. Meanwhile the assembly looks a bit like a porcupine with #5-40 socket head capscrews in all the holes that will eventually get the 1/8" long setscrews. My fingers are sticking to the keyboard ( residual Loctite) so I better go wash my hands before the keyboard and I become one.
http://i307.photobucket.com/albums/nn294/BrianRupnow/SEMIASSEMBLED002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/SEMIASSEMBLED004.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/SEMIASSEMBLED003.jpg

brian Rupnow
08-25-2010, 07:09 PM
Well guys---Its all assembled, and I must say, it seems to work fine. The mechanism works freely. I have installed it on a temporary base to show the "action" of how it works. In the first picture, the govenor is in a 'balls in" condition, which would indicate no engine speed, or a very low speed. the arrow drawn on the temporary base shows the "mousehole" which the exhaust valve lockout" hides in when the governor is in this condition. The face of the aluminum main frame with the 'mousehole" in it will set about 0.030" from the side of the rocker arm on the Webster engine.
http://i307.photobucket.com/albums/nn294/BrianRupnow/finalassembly001.jpg

brian Rupnow
08-25-2010, 07:10 PM
And here we have it in a "balls out" condition. Centrifugal force has caused the balls to fly out into this condition as the engine reaches a high enough RPM to overcome the governor spring. This consequently tilts the top lever, which through the chain of other levers causes the "exhaust valve lockout" to advance out of the front of the main frame and slide under the rocker arm on the Webster when it is in the "exhaust valve open" condition. This prevents the engine from firing, as it can no longer build up compression, because the valve is held open. As the engine begins to slow down (The large flywheel is keeping the engine turning over, even though it is not firing). The governor turns more slowly, and returns to a "balls in" condition as the govenor spring expands to its "normal" length. This retracts the "exhaust valve lockout" into the "mousehole" in the main base. Now that the rocker arm is no longer held open, the exhaust valve can close and the engine will fire again, picking the RPM up and repeating the cycle. I am really looking foreward t getting my #5-40 set screws so that I can do a test run of the governor, using my variable speed drill. I will post a video.
http://i307.photobucket.com/albums/nn294/BrianRupnow/finalassembly002.jpg

Doozer
08-25-2010, 09:04 PM
Brian- It looks like you have as much fun mating components in solidworks as you do building them. Governor looks great!

--Doozer

Duffy
08-25-2010, 09:36 PM
Brian, that is a GREAT effort and the results speak for themselves. I have a couple of questions for you;- did it not occur to you to raise the engine assembly on 3/8" blocks so that you could have added a thicker brass or zamak rim to the fylwheel? I would think that even a 5/16" increase in flywheel radius would have given all the momentum you could want.
While it IS a fine piece of work, what does a 3-ball governor do better than a 2-ball unit?

Tony Ennis
08-25-2010, 09:48 PM
What a great posting! Keep it coming!

brian Rupnow
08-26-2010, 07:11 AM
Duffy---It did occur to me to rise the engine up, or even to mill a slot below the flywheel for clearance, but it was easier to move the outboard bearing support. What will a 3 ball do better?---maybe nothing, but I've already built a 2 ball version two years ago.

brian Rupnow
08-26-2010, 05:59 PM
So chaps, here it is!!! The video I promised earlier, driving the governor with my variable speed drill. It has quieted down a lot after 10 minutes of continuous running. The action of the governors and lever mechanism works exactly like I had anticipated. I'm not certain that turning the Webster engine into a Hit and Miss will be succesfull, but the governor itself is indeed a success.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/th_TESTRUN--3BALLGOVERNOR.jpg (http://s307.photobucket.com/albums/nn294/BrianRupnow/?action=view&current=TESTRUN--3BALLGOVERNOR.mp4)

dp
08-27-2010, 01:44 AM
Brian, that's one hell of a nice governor you've built there. I've been a big fan of flyweight governors since the first time I saw one running on a penstock driven generator. I think now it must have controlled a gate electrically. It had 6" balls at least, and turned with high grace atop the stack of machinery it adorned. I can't recall where it was as I was a very small kid at the time, but it had to be a dam on the Williamette river in Portland, OR.

Richard Wilson
08-27-2010, 07:22 AM
Nice work!
Lots of full sized engines, especially steam engines had the governor driven by a belt. at the speeds we are looking at here, I don't think 'belt lag' is going to be a problem.
Not all hit and miss engines had the governor operating on the exhaust valve, some worked by holding the gas valve shut so no fuel could get in.

Regards
Richard

ldn
08-28-2010, 08:31 AM
Looks great. I've always liked those kinds of governors and have wanted to build one too.

From the video it looks like the balls may not be tracking each other very well. I'm not sure if that's an issue or not, it probably doesn't matter. It might be causing some vibration.

brian Rupnow
08-28-2010, 11:47 AM
So, here we are, all ready to rock and roll, and wouldn't you know it----I don't have an o-ring the right length, and the place where I buy them isn't open untill Monday!!!! If I manually lift the balls (Nevermind ya filthy bugger), the engine does miss. Now I wait untill Monday to see if it works.
http://i307.photobucket.com/albums/nn294/BrianRupnow/readytorun002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/readytorun003.jpg

brian Rupnow
08-28-2010, 11:51 AM
IDN---good eye!!! I never noticed untill after I had made the video that one of the pins had come out that holds the upper arms with the brass ball on it to the arm below which runs to the bottom yoke. A little locktite on the ends of the pins has fixed that.---Brian

brian Rupnow
08-28-2010, 12:06 PM
IT WORKS!!!! IT WORKS!!!! I just had the brainwave of holding a third small pulley on a shaft in place as a belt tensioner while the engine was running. As soon as the governor began to rotate, the entire "hit and miss" cycle happened just as I had hoped it would. Its going in and out of hit and miss mode quite rapidly, which indicates that I need a stronger spring on the stempost, but it is definitly operating as a hit and miss engine!!! YIPEEEE!!! I will get a correct size o-ring and a slightly stronger spring on Monday, and get a video up.---Brian

brian Rupnow
08-28-2010, 03:26 PM
Now I have to put my thinking cap on and think on this for a while. Wife and I just sat on the back deck, under beautifull sunshine, 85 degrees F and drank a bottle of Australian wine, Yellowtail Shiraz---MMMMmmmmmm. Oh yes---I was thinking---the engine starts well, revs up to midrange speed, the governor balls fly out at what I would deem an "appropriate time" and then the engine goes into "miss" mode. The "miss" mode is very brief, perhaps one or two full engine revolutions, then the engine slows enough for the balls to pull in and start the engine firing again. This rapid cycle between firing and missing is what I want to correct. This, if I remember my engineering lessons from the distant past, is called "Hysteresis". I want the governor to engage exactly as it does now, in the RPM range it does now. However, I want more of a time lag between the engagement of the "exhaust valve lockout" and the disengagement of it. (This will give more "missing" cycles between when it starts to miss and stops missing ). I don't think a stronger governor spring would give this effect. All it would do is increase the point at which the RPM range got high enough to force the balls into the "full out" position ----and it would also shorten the time span of the 'miss" cycle proportionally, because the stronger spring would retract the balls sooner. It seems to me that perhaps the secret lies in the way the bottom lever engages with the slot in the top of the "exhaust valve lockout". Right now, it engages pretty well 1:1---That is to say, for every increment of movement of the lever, there is an equal increment of movement in the "exhaust valve lockout" (the red thing in the cad model). Perhaps if I were to widen the slot in the "exhaust valve lockout", on the side away from the rocker arm, then the exhaust valve lockout" would still engage at the same time, but there would be more of a delay before it disengaged, because the lever would have to move though a "dead space" before it came in contact with the other end of the slot in the "exhaust valve lockout" and caused it to completely withdraw from under the engines rocker arm. If you can understand this, and agree or disagree, let me know please.----Brian

brian Rupnow
08-28-2010, 04:12 PM
Since I had a heavier spring here, (.023 dia. wire as opposed to .019 wire) I went ahead and tried the heavier spring approach. It didn't work. In fact, with the current pulley set up, the balls didn't create enough centrigugal force to overcome the springs strength to make the balls fly out far enough to even begin the "hit and miss" cycle. I had to try. In the wonderfull world of "Try it and see if it works" engineering, you have to try every approach available.

dp
08-28-2010, 04:56 PM
What you need is a heavier flywheel, Brian. That is the only energy present to keep the crank turning while the engine is not running. That will also keep the flyweights up longer.

The spring sets the RPM at which the miss starts (along with the weight of the flyweights, of course), the flywheel sets the point at which the hit starts when coming off a miss cycle.

And it's just occurred to me how you can up the flywheel weight. Hollow out the brass part you made, shave down the part it mounts to, and fill the gap with lead. There's 1.6 million pounds of it out on the highways you can use :)

brian Rupnow
08-28-2010, 05:02 PM
What you need is a heavier flywheel, Brian. That is the only energy present to keep the crank turning while the engine is not running. That will also keep the flyweights up longer.

The spring sets the RPM at which the miss starts, the flywheel sets the point at which the hit starts when coming off a miss cycle.

DP---That flywheel IS a heavy little bugger. I made it from solid brass. and fitted it over the existing aluminum flywheel. You may well be right, but since I don't have the option of making the flywheel heavier, I have to find another way. The engine is NOT slowing down all that much when the governor balls start to come into a "balls in" position. Right now the engine comes up to speed, the balls fly "out", the engine misses, and almost immediately the balls start to come in and the engine starts firing again. I have to come up with a proper "delay" so that the balls coming into the "in" position don't immediately pull the "exhaust valve lockout" out from under the rocker arm. Hmmmm---There's food for thought there---Perhaps I need a lighter spring. The balls would fly out and engage sooner, but they wouldn't be so quick to retract the "exhaust valve lockout" either---

RichardG
08-28-2010, 05:50 PM
Brian,
You could drill out some of the brass plugs on the back side of the flywheel where they don't show and pour some lead in would make the flywheel heaver quick .
Richard

ldn
08-28-2010, 06:05 PM
Old style carburetors used to have a device called a "dashpot".

http://en.wikipedia.org/wiki/Dashpot

It would reduce the rate at which the throttle was allowed to close when you let up on the pedal.

Maybe you could make something similar to provide mechanical hysteresis. For example, imagine a piston sort of like in an air pump. Push it in and a ball valve opens and it moves easily. Pull it out and the ball valve closes and air has to be sucked in through a very small hole, slowing down the rate at which the actuator can disengage.

I've seen the videos of the old hit and miss farm engines and they do seem to go quite a few cycles in miss mode before firing again.

dp
08-28-2010, 06:09 PM
The next trick then is to make the flyweights heavier, or make the arms longer, or both. You can also up the pulley ratio to make the flyweights spin faster for a given crank rpm.

You can also invert the flyweight mechanism so they swing down rather than up, and put a detent in shaft where the collar slides to create controlled hysteresis. A detent can be as simple as a small bb sized ball pushed out by a mild spring such as in a ball-point pen. The ball shape has a high release pressure but very little drag once it is pushed in by the sliding collar.

Hollowing out the flywheel and packing it with lead is easier, though.

The Artful Bodger
08-28-2010, 06:37 PM
Hmmmm....

I feel the duration of the miss period is influenced by the power of the hit and the friction losses during the miss. I have a feeling that a heaver flywheel may invite double hits.

One way to reduce friction of the miss period may be to reduce friction in the exhaust path.

John

Toolguy
08-28-2010, 06:37 PM
I would agree with making the slot in the red lockout block wider as you suggest. I would also make the original spring have a little more resistance by taking it off, stretching it a little and re installing. That would make the engine run to a little higher RPM before engaging the red block and possibly make more revs before disengaging the red block. It's kind of hard to tell without being able to study it in person.

brian Rupnow
08-29-2010, 07:48 AM
Thanks guys, for all your excellent suggestions. The dashpot is a good idea. Before I start to add parts, I want to play more with the parts I have. It seems to me that to get the maximum number of revolutions from a power hit, I want to reduce the mass of the governor somewhat, making it easier to spin. I currently have a set of 5/8" diameter balls on it. I have a set of 1/2" balls left over from my governor build two years ago, and this morning I will try them. I will also try a weaker spring. in theory these two changes should let the engine get more revolutions per "power hit" and a weaker spring with smaller balls should delay the collapse of the governor and the consequent rapid decay of my miss cycle.

brian Rupnow
08-29-2010, 07:59 AM
Brian,
You could drill out some of the brass plugs on the back side of the flywheel where they don't show and pour some lead in would make the flywheel heaver quick .
Richard

I just looked it up in the Machinery Handbook---Brass weighs .304 pounds per cubic inch. Lead weighs .409 pounds per cubic inch. Thats a difference of 0.1 pounds per cubic inch. the flywheel is 3/4' wide with a total of 8 brass plugs. Thats a total of 0.36 pounds of brass---If changed to lead it would be a total of .48 pounds of lead. Thats a hell of a lot of work for a gain of 0.12 pound. When I made the large brass flywheel to fit over the existing aluminum flywheel, it added 2 1/4 pounds.

brian Rupnow
08-29-2010, 08:53 AM
I just tried it with the 1/2" diameter balls, and I see some improvement. I will be able to judge things much better come Monday, when I can get an o-ring the correct length and have access to some different and lighter springs.

Tony Ennis
08-29-2010, 10:54 AM
When I made the large brass flywheel to fit over the existing aluminum flywheel, it added 2 1/4 pounds.

Also important is where the mass is added with respect to the axle.

brian Rupnow
08-30-2010, 11:47 AM
This morning I rushed across town and bought a pair of o-ring drive belts the correct length, (one is a spare) and a weaker compression spring for the governor stempost. I had to fire it up as soon as I got home. There is considerable improvement in the hit and miss action, but its not quite where I want it to be yet. I know you fellows are anxiously awaiting a video, so here you go. This is not final, but it does very well to show the Webster engine running in "hit and miss" mode.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/th_HITANDMISSWEBSTER.jpg (http://s307.photobucket.com/albums/nn294/BrianRupnow/?action=view&current=HITANDMISSWEBSTER.mp4)

dp
08-30-2010, 12:31 PM
I just looked it up in the Machinery Handbook---Brass weighs .304 pounds per cubic inch. Lead weighs .409 pounds per cubic inch. Thats a difference of 0.1 pounds per cubic inch. the flywheel is 3/4' wide with a total of 8 brass plugs. Thats a total of 0.36 pounds of brass---If changed to lead it would be a total of .48 pounds of lead. Thats a hell of a lot of work for a gain of 0.12 pound. When I made the large brass flywheel to fit over the existing aluminum flywheel, it added 2 1/4 pounds.

Yep - you're right about that. It looks bigger in the pictures! The dashpot is a good idea, but that's what the flyweights should be doing. So heavier weights or a faster governor are still options (as is inverting the flyweight arms). Inverting the arms lets you use spring tension to set the hit speed whereas now the spring sets the miss speed.

brian Rupnow
08-30-2010, 03:39 PM
Well, I think this is about as good as its going to get. The project is a success. I have turned a 4 stroke Webster I.C. into a hit and miss engine. The reality of the situation is that the governor is way too large in relationship to the bore of the engine. I kind of knew that when I set out to do this, but its been a fun project. On a "to scale" hit and miss engine with the governors set into the flywheels, the governors are much more sensitive to engine RPM than what I have here. Add to this the fact that I am limited in terms of how large a flywheel I can mount to this existing engine. The thing I like is that I can run the engine in normal non hit and miss form by simply removing the o-ring drive belt. I have to do a bit of tidy up now, and find a new location for the gas tank, but other than that I will call this project finished. Thanks to all who followed along and expressed interest.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/th_Websterhitandmiss--take-2.jpg (http://s307.photobucket.com/albums/nn294/BrianRupnow/?action=view&current=Websterhitandmiss--take-2.mp4)

ldn
08-30-2010, 03:52 PM
Looks good! I think you've done it. It's nice to see one of those ball governors actually running and working. I've only seen them in museums.

In the second to last video it sounds like it is snoring.:)

I liked DP's idea of adding a detent -- that way it holds at the detent position with the exhaust valve fully open until it is ready to start firing again.

I was also wondering what would happen if you let the ball governor freewheel, like a bicycle hub. That would give you instant response to speeding up and delayed response to slowing down.

Probably not ideal for a hit and miss engine, where it would cause the engine to stall under sudden load, but a neat mechanical concept anyway.

The Artful Bodger
08-30-2010, 04:04 PM
Excellent work and a very impressive outcome!:)

spkrman15
08-30-2010, 05:17 PM
Nice project and post Brian. Thanks. I really enjoyed it. I just wish i had the time.... :)

Rob :)

brian Rupnow
08-30-2010, 08:14 PM
Nice project and post Brian. Thanks. I really enjoyed it. I just wish i had the time.... :)

Rob :)

Thanks for the compliment. Be carefull what you wish for. The only reason I'm screwing around with this is because I don't have very much real work.