Installing SMS-50 sickle bar on my 953

[c-series don 8,688]

 @cafoose Let me start by saying that I’m far from an expert on these things. I’ll tell you what I do know, I hooked mine up to the manual lift using it mostly for transport. The little bit that I used it I lowered the main frame down and ran the bar on the ground. However in the area I was cutting I knew there was nothing to hit, like rocks, broken off metal fence posts etc. I never really messed with it enough to see if I could run it off the ground, say 6” or so? That’s probably how I would want to run it if I was going to seriously use it. 
 I bought mine for two reasons, I am a collector of all things Wheel Horse! So as most of us know a sickle bar is a rare attachment, and when one became available to me I had to buy it. The second reason was that my wife and I have this dream of someday owning a small farm and I would use it around there. That will probably never happen, but if it does I’ll be ready with 18-20 Wheel Horses. All with different attachments ready to go to work 😂👍🏻

[Racinbob 11,050]

On 6/7/2024 at 10:24 PM, cafoose said:

I got the sickle mounted on the tractor It looks good to me so far Looks like the lift lever mounted to the sickle is too sloppy to lift the bar in the last two pictures. Any suggestions how to fix it? Also, do I need to hook up the hydraulic lift to it? If so, how can I do it? Is it supposed to ride on the ground or do I need to somehow hold the frame up a little?

 

I'm sure you know that lift is only to lift it over an object, not raise it up to the vertical position. Your tractor life raises the wobble box and you manually lift the bar vertical to the transport position. It's held there with a bar connected to the tower. I use a chain. You do have a lot more wear at a critical area. It was probably slipping off multiple times because the slop wasn't taken out. I rarely even lower the wobble box because 95% on my mowing with it is done at about a 45° angle. I do mow under a few large pine trees with the bar down but I still don't lower the box. 

 

Edited June 10 by Racinbob

[cafoose 3,354]

5 minutes ago, Racinbob said:

It's held there with a bar connected to the tower. I use a chain.

Do you have any pics of how your wobble box connects to the tractor lift? I'm still not sure how to connect it.

7 minutes ago, Racinbob said:

You do have a lot more wear at a critical area. It was probably slipping off multiple times because the slop wasn't taken out.

Do you have any suggestions how to take out the slop? My neighbor suggested maybe a small winch to raise and lower the cutting bar.

[Pullstart 62,834]

On 6/7/2024 at 10:24 PM, cafoose said:

Looks like the lift lever mounted to the sickle is too sloppy to lift the bar in the last two pictures. Any suggestions how to fix it? Also, do I need to hook up the hydraulic lift to it? If so, how can I do it? Is it supposed to ride on the ground or do I need to somehow hold the frame up a little?

Awesome progress!  The pulley size should yield 1482 RPM at WOT on the engine.  I bet you’ll find it still prefers 1/2 throttle.

 

As for lift, my research says there are two lifts.  One is for the height of the mower wobble box and the side arm is for the angle of the mower.  You’ll need to tighten that side lever up somehow.  Does it just bolt together?  Shorter bolts?  Washers?  Something to take up the slack.  You’ll also need the hydraulic lift on the tractor hooked to the wobble box frame.  

[cafoose 3,354]

4 minutes ago, Pullstart said:

1482 RPM at WOT on the engine.

Here's what I get based on 3.25 drive pulley, 8.5 driven pulley, and 3600 rpm 1376.4705882352941 RPM

7 minutes ago, Pullstart said:

You’ll need to tighten that side lever up somehow

I sorta realized that. The lever slides onto a shaft. I think the hole in the lever where it slides onto the shaft is worn out. How can I fox it? with a bushing is my thought. Also maybe w washer?

11 minutes ago, Pullstart said:

You’ll also need the hydraulic lift on the tractor hooked to the wobble box frame.

That's what I need to figure out

I'm thinking of using a winch or something to raise and lower the bar because that handle makes it heavy.

[Racinbob 11,050]

Keep in mind that your sickle has several differences than mine. Here's the lift for the wobble box.

 

 

@Pullstart That lift in the bar itself isn't really for adjusting the angle. It's just to lift it a few inches to clear an object. I don't think there was anything to actually set it at an angle. Here's my scientific method.

 

 

This works fine but it does get in the way a bit on the taller stuff. It doesn't let it fall backwards easily. I spent a few hours mowing with it yesterday and was pondering that. Maybe an electric linear actuator mounted close to the wobble box?

 

 

[Racinbob 11,050]

8 minutes ago, cafoose said:

Here's what I get based on 3.25 drive pulley, 8.5 driven pulley, and 3600 rpm 1376.4705882352941 RPM

 

 

I said I'd check the actual rpm a while back and I haven't yet. I'll do that this morning. Just a swag estimate but I figure I'm running the engine at about 1200. With my 2.5" to 5" reduction obviously that's 600 at the sickle. I'll verify. Plenty fast enough.

[Pullstart 62,834]

15 minutes ago, cafoose said:

Here's what I get based on 3.25 drive pulley, 8.5 driven pulley, and 3600 rpm 1376.4705882352941 RPM

 

huh.  Coffee.  Mathin.  Yep, I got that too on the second go round!!  

[Handy Don 12,212]

43 minutes ago, cafoose said:

Here's what I get based on 3.25 drive pulley, 8.5 driven pulley, and 3600 rpm 1376.4705882352941 RPM

Unless, of course, the belt ride a bit high or low on one or the other or both pulleys, then there might be a variance of 1.34992314 RPM (plus or minus).

[Racinbob 11,050]

OK guys. Just spent a few minutes with the tach. 

 

 

So much for my SWAG estimates. I'm running the engine at about 1840 RPM. Faster than it sounded to me. So, with the 2.5" drive pulley at 1840 makes the driven pulley at 920. But there's another reduction. The pulley centered directly under the engine is a drive pulley and is another 2.5".

 

 

The belt from that goes around the 90° idlers to the 4" input pulley on the wobble box. That would be a driven pulley. That is turning at 512 rpm. I'm thinking that would be a good rpm to shoot for at the input of the wobble box. 

[cafoose 3,354]

26 minutes ago, Racinbob said:

So much for my SWAG estimates. I'm running the engine at about 1840 RPM. Faster than it sounded to me. So, with the 2.5" drive pulley at 1840 makes the driven pulley at 920. But there's another reduction. The pulley centered directly under the engine is a drive pulley and is another 2.5"

I was focusing on the first driven pulley from the engine. If it matches the rpm of your driven pulley I don't give a **** what the rest of it is because it's not gonna change Then I know the speeds are fine

[Handy Don 12,212]

Curiosity got the better of me and I did some time searching the all-knowing inter web.

 

It seems that several commercial implement manufacturers aim for around 1650 strokes per minute (~25 strokes per second) on a sickle--a stroke being a blade movement in one direction.

 

If one full rotation of the input pulley on your wobble box yields one “out and back” that’d be two strokes. Given that, 825 RPMs in gets the “right" blade rate.

 

The caveat here is that all the manuals I saw were for bars mounted on larger, liquid-cooled tractors which could run at ½ or ⅔ throttle safely. I’d think that on an air-cooled WH working under load that you’d want to run at least 2500-2800 RPM while still keeping the stroke rate from tearing the thing to pieces.

[Racinbob 11,050]

27 minutes ago, cafoose said:

I was focusing on the first driven pulley from the engine. If it matches the rpm of your driven pulley I don't give a **** what the rest of it is because it's not gonna change Then I know the speeds are fine

 Not necessarily true. The only pullies that I'm sure are the original size are the engine pulley and the wobble box pulley. I have no clue about the two inbetween. If those two are different on yours the final speed would vary.

 

3 minutes ago, Handy Don said:

Curiosity got the better of me and I did some time searching the all-knowing inter web.

 

It seems that several commercial implement manufacturers aim for around 1650 strokes per minute (~25 strokes per second) on a sickle--a stroke being a blade movement in one direction.

 

If one full rotation of the input pulley on your wobble box yields one “out and back” that’d be two strokes. Given that, 825 RPMs in gets the “right" blade rate.

 

The caveat here is that all the manuals I saw were for bars mounted on larger, liquid-cooled tractors which could run at ½ or ⅔ throttle safely. I’d think that on an air-cooled WH working under load that you’d want to run at least 2500-2800 RPM while still keeping the stroke rate from tearing the thing to pieces.

 

That's interesting. If it translates to these little units I'm a bit slow. But I just go by the seat of the pants shake-o-meter and sound.

 

As far as engine RPM goes, I've never bought into the minimum speed thing to keep airflow up or to splash the oil enough. I'll run full RPM when needed for a given attachment like a mower deck, snow thrower, etc. I've been running hours at low RPM's for over 6 decades and never had an issue. 

[pfrederi 17,723]

I wouldn't worry about engine RPM either.Sickles do not use much HP.  Old sickles were drawn by one or two horses.  old troybilt tlllers had a front sickle and were 2.5 hp.

[cafoose 3,354]

36 minutes ago, Handy Don said:

If one full rotation of the input pulley on your wobble box yields one “out and back” that’d be two strokes. Given that, 825 RPMs in gets the “right" blade rate.

That's exactly what mine is, I just went and checked. One rotation of the wobble box pulley is two strokes. That's one direction being one stroke.

[squonk 41,067]

Install a variable pitch pulley and fine tune  the speed. 

 

[cafoose 3,354]

@Racinbob @Lane Ranger I disassembled and cleaned the cutter bar today. The wobble box to cutter bar pin looks good to me and no play in it I had a visitor watching me work

 

[evanloock 221]

I have a SMS-50 that came with my early (Ross steering) 953.  If you need any pics of it, I'd be happy to help.  Like most I have seen, the one on my tractor was running off the PTO that came with the RMR-483, not the small engine pulley that was made for the sickle mower.  I'd love to find one of those.  Part # 3694.

[cafoose 3,354]

52 minutes ago, evanloock said:

I have a SMS-50 that came with my early (Ross steering) 953.  If you need any pics of it, I'd be happy to help.  Like most I have seen, the one on my tractor was running off the PTO that came with the RMR-483, not the small engine pulley that was made for the sickle mower.  I'd love to find one of those.  Part # 3694.

Still trying to get mine hooked up. By all means post any pics you can especially of the mounting to the tractor and PTO and belt configuration. For $20 you can post all the pics you want for a year

https://www.wheelhorseforum.com/store/

[cafoose 3,354]

I got the sickle working My high tech height adjustment works fine The PTO isn't bolted down to the drive pulley. No bolt holes in either the PTO or the pulley Do I need to change the drive pulley and the PTO to get the bolt holes to bolt it down? @953 nut @Ed Kennell?

 

 

[953 nut 55,188]

@Sparky,  please put this thread in the Instructional Threads and Video section. It is very well documented and contains links to additional threads that will be a helpful resource for others.