Bolted sickle vs rivitted sickle

[Dan Nickels]

I have an IHC model 100 balanced head sickle mower (had it for 40+ years). I decided to upgrade to bolted sickle. Bought the knife and couple boxes bolts for infield repairs. 2 trips around 6 acre field and knife started clattering and jamming. Bolts through the head assembly were missing or broken..Back to shop and replaced bolts with new and put them in good and tight..2 more trips and same scenario.. Again replaced and tightened bolts and now missing sections.. 2 more trips and same thing...I am now out of the longer bolts for knife head...So... I put rivitted knife in and mowed rest of field (rivitted knife also ran much quieter) I then moved to next 4 acre field and mowed with no problems..
My question is... Does everyone else use bolted sickle with no problems? Am I doing something wrong? I expected better results from $250 knife!?!?
Thanks for any thoughts.....Dan

 

[joeysmith]

The new knife was registered correctly?

 

[rustred]

i been using bolts for years and years, no problems. do you have the correct bolts ? they pound in from the bottom then use a lock nut on top.

 

[Bob Bancroft]

I have an IHC model 100 balanced head sickle mower (had it for 40+ years). I decided to upgrade to bolted sickle. Bought the knife and couple boxes bolts for infield repairs. 2 trips around 6 acre field and knife started clattering and jamming. Bolts through the head assembly were missing or broken..Back to shop and replaced bolts with new and put them in good and tight..2 more trips and same scenario.. Again replaced and tightened bolts and now missing sections.. 2 more trips and same thing...I am now out of the longer bolts for knife head...So... I put rivitted knife in and mowed rest of field (rivitted knife also ran much quieter) I then moved to next 4 acre field and mowed with no problems..
My question is... Does everyone else use bolted sickle with no problems? Am I doing something wrong? I expected better results from $250 knife!?!?
Thanks for any thoughts.....Dan

I use only bolts on my old AC twin wheel sickle bar mower without any issue.
It sounds like you didn't have them tight enough to draw the serrated part of the bolt up into the knife bar? Bolts/nuts hitting something?
If I ever break a bolt, there's no such thing as the remains of it missing, because they fit in the bar so tight. Takes a good punch with a good back up to get them pounded out.

 

[DanielW]

Not sure about the 100 in particular, but on the earlier IH pitman ones and on my IH 990 haybine (same balanced head design), IH offered different hold-downs for bolted sickles. The standard hold-downs have just a little too low of an arch to clear the nuts properly. That might be your issue, although if you were able to slide the knife in without issue then perhaps not - I would have thought it would have fought you when trying to put it in. Did the knife slide in easily? How is the clearance under the hold-downs? Also check the end of the bar where the knife slide in the outer shoe for clearance too. Who knows, maybe someone goofed at the factory and put the bolts in the wrong way with the nuts facing down? These days I just buy aftermarket high-arch hold-downs for the whole bar.

A lot of old sickle mowers have seen various parts cobbled on them over the years - JD/Ford pattern guards bolted to IH or Massy mowers (or vice-versa) so the clearance beneath wasn't quite correct, NH wear plates on IH pattern bars that hold the knife out too far, etc. Many times it will work OK with these improper parts cobbled on there, but maybe with a bolted sickle the clearance was just not quite right somewhere due to something like this?

Don't just look at the head-end of the bar either: The fact that the knife head bolts were the ones that broke is just because they're the ones sending power to the rest of the bar. You issue could very well be elsewhere on the bar.

I know I'm alone in this, but I never understood the love bolted sickles. If everything's adjusted properly, you can pull a knife out and put it in quite quickly. And it takes no time to smack a rivetted section off and put a new one on. In my mind, if you break a section, it's worth it (to me) to spend a couple extra minutes taking the knife out to inspect the rest of the knife and tune up accordingly. At least for a sickle mower. For something like a 20' combine header, that'd be a different story.

 

[Phill Tibbetts]

I have used bolts for years and never had trouble with them loosening. Hate to think I had to go back to rivets.

 

[paul]

Something was wrong. Used many different riveted and bolted sickles on the combines, hay mowers, swathers, etc. generally moved most to bolted and liked the easier repairs of a broken section, not much difference otherwise.

Did you over tighten and stretch the bolts?

Were the bolts too long and hit the hold downs?

Were the heads the proper design; flush, bulb, too fat a head or such? Proper bevel if flush mount for the bar?

Something is wrong with what you are doing, the bolts have always been as tough as the rivets in my experience on various applications.

Paul

 

[Briar Hill Brittanys]

Went with bolted sections a few years back for my JD #9W. Also replaced the hold-downs with the higher arched adjustable ones. Performance wise, I haven't noticed any difference, but it is easier to replace broken sections. Like stated above, the hardware is inserted from the bottom of the bar, nuts on top.

 

[Dan Nickels]

Thanks for all the replies!! the first time bolts broke was the factory installed bolts in new knife.so most likely installed correct. The next to times, I had put bolts in by driving them flush with bottom then putting nuts as tight as I dared to (I even broke one by overtight). Not hitting on arches because I am using high arch holddowns.Knife slides in and out with out binding of hitting.No problems with rivited sickle . .I guess I will take bolts out of new knife and replace with rivits.
Thank you guys...Dan

 

[rustred]

Show us these bolts and nuts .

 

[Willow Lane]

Never been around the 100 mower, but is it possible that you have some slack where the knife attaches to the wobble box, basically where the pin goes into the bushing in the head of the knife. Since you have a new knife, the bushing should be fine, but if whatever it has that goes into the bushing is worn, the knife will stop at each end of the stroke and get quite a snap when it starts going in the other direction.

 

[Dan Nickels]

...does anyone know happen to know a torque spec for these bolts?? Perhaps if I used a torque wrench in stead of guessing how tight?? Maybe??

 

[Roger in Iowa]

Are your guards worn out with very rounded cutting edges. That would cause heavy loads to the knife.
Something is not right.

 

[Dan Nickels]

I broke the cutter bar last year (mowing too close to tree in fenceline), and put new guards on when I replaced cutter bar.

 

[Dan Nickels]

I still maintain nothing wrong with mower... Works great with rivits sickle.. I am thinking bolts on knife head were not tight enough... Hoping to get torque spec...

 

[joeysmith]

Ime when a repetitive issue like that happens its cause its not registered properly.
Odd that the new sickle would be different but that would be the first thing I would check
Like others I have never had issues with the bolts holding

 

[rockcreek4630]

I have an IHC model 100 balanced head sickle mower (had it for 40+ years). I decided to upgrade to bolted sickle. Bought the knife and couple boxes bolts for infield repairs. 2 trips around 6 acre field and knife started clattering and jamming. Bolts through the head assembly were missing or broken..Back to shop and replaced bolts with new and put them in good and tight..2 more trips and same scenario.. Again replaced and tightened bolts and now missing sections.. 2 more trips and same thing...I am now out of the longer bolts for knife head...So... I put rivitted knife in and mowed rest of field (rivitted knife also ran much quieter) I then moved to next 4 acre field and mowed with no problems..
My question is... Does everyone else use bolted sickle with no problems? Am I doing something wrong? I expected better results from $250 knife!?!?
Thanks for any thoughts.....Dan

You say the riveted one is quieter this is your best clue find why the bolted one is making more noise.

 

[rustred]

View attachment 126276...does anyone know happen to know a torque spec for these bolts?? Perhaps if I used a torque wrench in stead of guessing how tight?? Maybe??

Yep that’s the bolts and nuts. Well if a person can’t tell what’s tight enough on a 1/4 inch bolt Houston we have a problem here. 3/8 ratchet and 7/16 socket I hope ur using. Even if you did torque them you need an inch pound torque wrench. But never heard of such a thing yet. Tight is tight and that’s it.

 

[rustred]

You say the riveted one is quieter this is your best clue find why the bolted one is making more noise.

Ya I bet because he don’t have the bolts tight enough. You can feel when the bolt is pulled up to its end then give it a bit more to make the nut tight.

 

[DanielW]

I'd have a hard time believing the bolts weren't tight enough from the factory. Sounds to me like a clearance problem. Either a wrong guard is on there somewhere, a hold-down has too little clearance somewhere, or the adjustable top ledger at the far end of the bar is a little too low for a bolted sickle. If it was rattling and clanging, something was making contact where it shouldn't be.

I'd pull the knife out and look for witnesses/shiny spots around all the guards, hold-downs, and shoes. You should be able to find your culprit. I wouldn't be changing the whole knife over to rivets: Even though I said in my earlier post that I don't get the huge appeal of bolts, there's certainly nothing wrong with them, and a proper bolted knife should work in that mower just fine. If it didn't, something is awry somewhere, and should be looked into regardless.

The only other thing I can think of: Are you sure your dealer sold you the correct knife with the correct knife head? The IH haybines like the 990 and 1190 used the same IH balanced drive, but the knife heads were just a little different between the their haybines and sickle mowers. Someone gave me their old knife from a 1100 mower (which I believe is just a slightly newer version of your 100) to use in my 990 and the knife head was 'almost' the same, but not quite (I think the pin connection point was a smidge further ahead on the sickle knife if I remember right). If your dealer ordered a knife meant for the IH balanced head haybines rather than their sickle mowers, the geometry of the knife head would not be right and it would tear something up. Do you have the part number of the knife they ordered?