Sickle bar turned to banana

Bkpigs · Jul 31, 2013

Putting new knives on my sickle bar mower. As I am hammering the rivets in I am noticing the bar is curving up like a banana towards the knife blades. I am hammering the rivets on my vice so it is being done on a flat stable surface. Is this normal? Will it straighten out after use? Thanks.

tbish · Jul 31, 2013

its normal hammer it back straight as u go

Traditional Farmer · Jul 31, 2013

Need to hammer it on a long flat surface that the whole blade can lie on flat.A riveter would be better and if all else fails you can buy a new sickle with sections installed for not much more than the sections cost from Webb's Sickle Service
and their sections and blade material is better than most.

James Howell · Jul 31, 2013

You will probably want to straighten the knife after all the knife sections are installed.

Lay the knife on the floor and a rubber mallet will probably work.

If the knife is not straight, then there may be wear and friction on top of the sections from the knife hold-downs.

There is a sickle section tool that installs the rivets on knife sections.

It may take a little longer, but does an excellent job on the rivets.

The sickle section tools are available from TSC and others.

Hope this helps.

Leroy · Jul 31, 2013

Depending on how that vise is mounted it may not be as stable a unit as you think and may not get rhe rivets completely tight. I know mine, at least a 60 year old vice but mounted on a wood workbench is not that stable as there is enough give in the bench, I have a hundred pound anvile I use, at least I always thought it was a hundred pounder but it is the same size as ones I see called a 125# or 150# and anymore I cannot lift it and always was just barely able and the wood stand it is on is made out of about an 8" block. Not much vibration here.

Bret4207 · Jul 31, 2013

After doing it both ways, I've never understood why anyone would use rivets instead of nuts and bolts. Tradition maybe? A couple bucks difference in cost? All I know is with the nuts and bolts replacing a bad section goes a lot faster and if I get a loose section I can fix it right then without resorting to hammers and anvils and blood.

DaninKansas · Jul 31, 2013

This.

John B. · Jul 31, 2013

I never messed with replacing all the sections. I might put one in here or there if the sickle was fairly new. I always bought a new sickle for my sickle mower for $63. Bring it home and put it in. I can't remember the last person I heard putting rivets in their sickle until now..
No offense.

Traditional Farmer · Jul 31, 2013

Alot of the older sickle bar mowers don't have enough clearance on the hold downs and on the guards to use the bolts

old · Jul 31, 2013

I gave up on rivets a few years back and only use bolt on section now days. Saves on time and money in the long run and I have yet to find a sickle mower that I can not use the bolts on yet. Yes you may have to reset the hold downs but that is not all that hard to do. To date I have switched out a NH450 a NH44/45/46 a Farmall mounted on that fits the A and in my case it is on my BA which is half B and half A. Also did the bolts on a JD#9 and an A/C belly mount for the C I have

LonM · Jul 31, 2013

I still rivet ours, and its not that big of a deal versus bolts (we have bolt type sickles too on other stuff). When the whole thing gets curved from working on it you can put it in a vise and straighten it out with a hammer or by putting pressure on certain points to get it straight. Running a crooked sickle will wear things out faster and not cut as well. Just don't assume it will straighten itself out (been there).

Bob · Jul 31, 2013

You MAY be mashing the rivets more than you need to.

If you do not "set" them enough, you will have loose, rattling sections in a few hours.

If you smash them TOO much the deforming of the knife "back" will be even worse.

You need to find a balance between the two, and mash the rivets only enough so the sections stay tight!

retired farmer · Jul 31, 2013

You are mashing the rivets down too hard. Use the round head on a ballpein hammer to round the ends. I have a rivet punch that is for rivets, it has a depression in the end specially to form the ends. If the bar starts to curve up, it will also lengthen the bar and throw the sections out of register. Might be better to buy a new bar.

rusty6 · Jul 31, 2013

(quoted from post at 05:02:43 07/31/13)

There is a sickle section tool that installs the rivets on knife sections.

<img src="http://i200.photobucket.com/albums/aa5/jameslloydhowell/John%20Deere%20Equipment/350%20Mower/Installing%20a%20New%20Knife/IMG_3216.jpg" width="650" />

.

Yes, the riveting tools work well and eliminate the hammering on rivets. But they do break. In the photo, notice that the other side of the tool is not closed. This is how they get broken. Closing up the other side while you wrench on the opposite side of the tool will give it added support and prevent breaking the riveting tool in half. Yes, I have seen it happen.
And its true, rivets do not take a big hammer approach. Better to tap away with a small one to gradually flatten the heads.
But having said that, I have mostly bolt in sections on my cutterbars now and would not go back to rivets. You might need different hold down clips to provide clearance for the bolts but the guards usually have enough room. Still, new guards can make an old machine cut like new so don't be afraid to replace them.

James Howell · Jul 31, 2013

Many years ago, rebuilt a knife on our 39N sickle mower.

All new sections and guards; <a href="http://www.youtube.com/watch?v=ZLND2DifdD0&feature=share&list=TL4KO_r6XCcyc">cut really good for the short time it was used</a>.

Bkpigs · Jul 31, 2013

Thanks guys, will take your advice.

Bret4207 · Aug 1, 2013

(quoted from post at 08:57:38 07/31/13) Alot of the older sickle bar mowers don't have enough clearance on the hold downs and on the guards to use the bolts

Yeah they will, Put the nut on the bottom. A lot of people seem to think the nut has to go on top. I don't believe there is a guard made that won't let the nut clear.

mkirsch · Aug 1, 2013

If you do that, you defeat the whole purpose of using the bolts.

The bolts are knurled so they draw into the bar and stay put. This makes it easy to replace sections; you just undo two nuts, swap the section, and nut 'em back up again.

If you put them down through you can't get to the nuts to replace a section without pulling the knife bar out of the mower or removing the guard.

BTW, my IH #22 mower doesn't have enough clearance for the nuts, top or bottom.

Bret4207 · Aug 2, 2013

Okay, you have the one sickle bar in the world that won't accept them, you got me there. As far as the "defeating the purpose", I don't know how many times I've put them in "upside down" and had absolutely no issue whatsoever replacing them. I can't think of more than maybe a half dozen times I've been able to reuse a nut and bolt after it's been on for however many acres. As far as I'm concerned they are consumables.

Sickle bar turned to banana

Bkpigs

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tbish

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Traditional Farmer

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James Howell

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Leroy

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Bret4207

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DaninKansas

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old

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