Messing around in the shop

[Eugen]

You had your full day of adventures @JSinMO. I'm even worse when it comes to work clothing, because I never bought any. I keep thinking I'll do it, but then it doesn't happen. Your sickle mower repair look good to me. It'll probably last for years, it's not what it look like, but how well it holds, right?

[Harry]

I agree with David on the work in the shop. and Eugen, JSinMo your fix on your sickle looks fine. I’m hoping to install my generator starter back on the 444 today. Then get to fire up the Kohler and check the oil flow after fixing the inlet pipe leak. Harry

[Eugen]

I agree with David on the work in the shop. and Eugen, JSinMo your fix on your sickle looks fine. I’m hoping to install my generator starter back on the 444 today. Then get to fire up the Kohler and check the oil flow after fixing the inlet pipe leak. Harry

Let's see that 444 running Harry!

[JSinMO]

@JSinMO Any bad day messing about in the shop ( as long as no serious injuries) is better than a "good" day sitting on the couch. imo.

Well said Mr Dave!

Back at it today. Took a look at the zero turn mower and sure enough one tank had more water that gas in it! drained the water and ran off the other tank and all is well, runs just fine. Now I just have to figure out how the water got in my tank in the first place.

Moved on to that 2N and verified it was a plug wire issue. This is why I don’t throw thing away. I dug out the wires from Herbie the truck and stuck it on the tractor. Along with a slight carb adjustment and it’s running smooth again! I’ll have to put new plugs wires on the list.

With that taken care of. I thought I’d try the sickle mower. As I suspected the pitman arm I made broke almost instantly!

However in the 8.2 seconds before it broke I confirmed everything was rotating and moving back and forth so that’s a win! I’m out of lumber so I’ll have to hunt up a couple of good pieces of hardwood and try again.

Even though I was taking care of problems that just sprang up it was still a satisfying day in the shop.

[Eugen]

Of course if everything works perfectly what would we do all day?!

I do wonder though, why would it break? Where are the forces acting on it coming from?

[JSinMO]

Of course if everything works perfectly what would we do all day?!

I do wonder though, why would it break? Where are the forces acting on it coming from?

I dont know what we would do! If the day ever comes that everything works perfectly I guess I’d have to thinks about what to do next!

The force is basically push - pull on the wood. The eccentric on the tractor end converts rotational movement to linear movement to move the knives back and forth.

There are a few reasons I think it broke.
1. The knives are still kind of sticky in the bar so there’s more force on the wood.
2. There is a ball and socket connection on the bar end. I don’t think I had enough spring tension on that connection to keep it locked so the was some shock load on the wood too.
3. I cut the wood too thin at the bar connection. I should have left more meat on it.
4. Last night I noticed a knot in the wood close the the bar connection. Because it’s a push - pull action you really want straight grain hardwood with no knots. They just make a weak point.

Well there’s a bit of a wooden pitman arm ramble for you!
I guess I could have shortened that up by just saying its still rusty and I should have gotten a better piece of wood!

[Eugen]

But like this I understand a little more about what's going on. Is there a reason not to use a steel bar/pipe?

[JSinMO]

But like this I understand a little more about what's going on. Is there a reason not to use a steel bar/pipe?

You can use steel for that connection but you risk doing damage to the bar or the eccentric and maybe the power take off on the tractor. The wooden pitman arm is a designed fail point. Most manufacturers back in the day built them this way. The idea is if there is ever an obstruction that stops the movement of the knives the wood is supposed to break before anything else can be damaged. Wood is cheap, metal components on the mower or tractor are not! Having said that I have considered using a metal bar instead. Since this is belt driven I’m thinking I could run the belt a little loose so it can slip if there is an obstruction but I’m not sure I want to try that yet!

[Spike188]

If the wood was replaced with spring loaded telescoping tubing, metal would work for a while. That is until it was left outside, rained on, and seized. Calculating the spring load needed would be fun.

[Eugen]

That makes sense, thanks! Why mess with something that worked well in the past.