Design and build side-shaft hit and miss engine from bar stock

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And this is the right point in a build to trot out my favourite governor story.
I grew up in the kinder, gentler, far more poverty stricken world of the 1950's. I have a firm belief that it wasn't necessity that was the mother of invention---poverty was. The lack of money created a world of tinkerers and inventors, simply because there was no money to buy the proper tool or machine. An older friend of mine, named Leonard had built a portable buzz saw for cutting firewood. This was basically a 48" diameter circular saw mounted on the chassis of a model A Ford, circa 1930 or 1931. The lengths of wood were lifted onto a tilting carriage, and the carriage was tilted into the saw to cut up lengths of firewood. The saw was driven by a flat belt and pulley arrangement that came from the rear of the old Fords transmission. Now, Leonard had a problem----The old 4 cylinder Ford engine had babbit bearings, so it did not take kindly to prolonged high speed revving. However, if someone didn't open the throttle and give it some gas when the log engaged the saw, the engine would stall. Leonard was a veteran tinkerer, and somehow come into the possession of a set of flyball governors off an old steam engine. He mounted them with a belt drive from the Ford engine, and hooked them up to the carburetor with a system of levers and pulleys. The theory was quite simple---under no load conditions the old Ford would set there idling, but as soon as the log engaged the buzz saw, the rpm's would drop off, and the flyball governors would open the throttle automatically. This was a perfectly good working theory!!! The problem was that Leonard somehow got one of his lever arrangements bass ackwards. When the last bolt was tightened, and the last brace welded in place, Leonard went to test his creation. He started the Ford---that part worked perfect. As soon as it started however, the flyballs began to fly outward from centrifugal force, and the farther out they flew, the more the lever mechanism opened the throttle. The engine went from zero to a zillion rpm's in the blink of an eye. Leonard leaped from the drivers seat and raced around the car to pull off the coil wire and shut down the engine---and at the same time the flyball governor self-destructed (it too was by then doing a zillion rpm's). One of the steel balls flew and hit poor Leonard directly in the kneecap and broke it into a dozen pieces--then the old Ford engine self-destructed in a scream of tortured babbit bearings and shattered castings!! Leonard eventually recovered, though he walked with a limp ever afterwards. We all survived the 1950's, but it certainly was a time that gave rise to a lot of interesting stories.---Brian.
 
. I broke the shear-pin in my lathe today. I have wondered ever since I bought that lathe what would happen if I ran it past the limits in power feed. Now I know

Do you not have a clutch mechanism between the power feed rod & the headstock shaft that it engages? Its kind of a rudimentary affair. Looks like a cylindrical collar with 2 set screws which act on compression springs which act on bearing balls which sit in matching divots. When the power feed sees torque resistance (set by the springs) they disconnect the drive to the power feed rod engagement & make an audible racket (balls are out of divots). The shear pin is typically the last line of defense & it s a steel roll pin if it has a clutch. At least this is the most common arrangement I have seen on almost every Asian lathe but maybe you have a different flavor. My (14x40) threading screw rod has only a brass shear pin, no clutch.
 
No, no clutch at all. Just the brass shear pin. This worried me at first, and I did seek out a shaft mounted torque limiting clutch to install. The price was $400, so I decided to suck it up and work with what I had. I did design and build a spring loaded carriage stop, which works great.--If you run into it with power feed, it just slides along. If you disengage the power feed and crank up to the stop by hand, it gives a good repeatable stop that you definitely feel. I was running the compound rest in the Y axis when I busted the shear pin. I'm happy to know that a brass shear pin actually does shear and not take out half the gear train.
 
Congratulations again Brian,
listening to the hit n miss it sounded to me that the engine needed quite a few hits to get up to speed, then coast for a similar time? I wonder if it just may be worth removing the off side flywheel and see what happens???
Probably weird thinking on my part only because I hear a friend's, "Farm Boy" running in the model cage at our local agricultural show amidst the other models. His little engine runs almost non-stop for the three show days.
I Look forward to the next installment.
John B
 
Ever since Photobucket got all crazy a year or so ago I have used a paid subscription to Image Shack. Image Shack has now quit working for me and I can not reach anybody at their head office in California to help me to get it working again. I have been very happy with Image Shack up until now.---Brian
 
No joy with the hit and miss action. The engine itself runs great, but I am afraid I am going to have to go for a redesign of the hit and miss mechanism. I will post this YouTube link, and then I probably won't post anymore on this engine until I have sorted out the hitting and missing. For some reason my Image Shack service has stopped working and I can't find anyone there to help get things sorted out, so I have lost my ability to post still pictures. Gahhhhhh
 
I may have solved my problems with Image Shack. This picture (if it shows up) shows that the weights added to my governor weights were not assed as in the 3D model I posted. I decided to mount the weights to the underside of the weights instead. They are less apt to hit the side of the cooling water tower when added like this.---Brian
pl7sCsGij
 
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I may have solved my problems with Image Shack. This picture (if it shows up) shows that the weights added to my governor weights were not assed as in the 3D model I posted. I decided to mount the weights to the underside of the weights instead. They are less apt to hit the side of the cooling water tower when added like this.---Brian
pl7sCsGij
Brian.
I don't see picture
 
For the past two weeks something has been fishy with the images. Some folks see them, some don't. For 2 or 3 days I tried to contact Image Shack to complain, but there is no way to contact them directly. My account is a paid account, so it should work fine all the time. Last night I thought "Maybe if I just log out then log back in to Image shack that will do something, and it did. I can now post pictures again. I really don't know whats going on.
pl7sCsGij
 
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If you can see that image, it must be that you can see them and we can't. I can't see it and couldn't see the one a couple of hours ago that Minh Tranh commented on.

I can upload pictures directly here, and they seem to work, with the "upload a file" button on the lower right. I've never used any of the services.
 
The email notice I got on my phone shows the picture but when I come to the website it is not there.
 
I need to talk with a tech person who is running this forum. My pictures are showing up on all the other forums except this one.
 
I spent most of today fighting the good fight. By the end of the day, I had achieved the closest to hitting and missing that I have seen since building the engine. I think that my flywheels need to be trimmed of some weight, and will do that tomorrow.---Brian
 
Brain !
I asked because I watched your video, in about 53 seconds, I saw the engine was slow, it go down
I have watched it many times but I still don't understand why

No joy with the hit and miss action. The engine itself runs great, but I am afraid I am going to have to go for a redesign of the hit and miss mechanism. I will post this YouTube link, and then I probably won't post anymore on this engine until I have sorted out the hitting and missing. For some reason my Image Shack service has stopped working and I can't find anyone there to help get things sorted out, so I have lost my ability to post still pictures. Gahhhhhh
 
Just my opinion Brian, but I just looked at your "Engine running scary fast" video again and I think your hit and miss issues might be carb related. Basically, I think you're lacking a bit of power. I remember when building/running your first hit and miss design, without the governor hooked up the engine would run so fast that it would self destruct (I can't remember who actually had an ungoverned high-speed failure during the build but one of us did) and there is a lot of flywheel on that engine as well. While this engine runs at a reasonable pace, it's not exactly screamingly fast without the governor, so I don't think it's making full power with that carb. Making a bigger bang on the 'hits' will reduce the number of hits required to get it back up to speed, plus accelerate the engine further into the 'miss' RPM region and give longer 'miss' times.

Btw - I have no idea about your picture issue, although it seems weird to me that you were having an issue with Image shack and this forum at the exact same time. My money's still on an Image shack issue. Hopefully the tech people will have some idea.
 

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