Splicing a sickle bar

[Freewheelin]

I have a New Holland 450 sickle mower that I use on food plots. Yesterday the bar broke at the end of the head on the hole for the 4th section. I see there are splicing kits but because of where the break is at I can't use a 2 piece like a lickity split. . The first 2 rivets on the head are unique to the bar. So removing a couple sections and sliding the long piece onto the nead isn't going to work. Even if I removed all the sections the ends aren't the same so that won't work either. I know welding is an option but it looks like the sections should be removed to get the bar flat & stright and then be welded to the section at the break. Correct? Short of finding a donor bar to splice or buying a new one, anyone have any ideas? Thanks y'all.

 

[Janicholson]

I have a New Holland 450 sickle mower that I use on food plots. Yesterday the bar broke at the end of the head on the hole for the 4th section. I see there are splicing kits but because of where the break is at I can't use a 2 piece like a lickity split. . The first 2 rivets on the head are unique to the bar. So removing a couple sections and sliding the long piece onto the nead isn't going to work. Even if I removed all the sections the ends aren't the same so that won't work either. I know welding is an option but it looks like the sections should be removed to get the bar flat & stright and then be welded to the section at the break. Correct? Short of finding a donor bar to splice or buying a new one, anyone have any ideas? Thanks y'all.

Welcome to YT forums. You solved your issue but didn't recognize it. Do take the few involved sections off and drive bracket. The take it to a professional welder for a fix. (with the sections taken out so the repair person can make all spaces correct. Not a big issue. Make sure all guides and clips are to manual specifications to avoid a repeated stress failure. Jim

 

[wore out]

I have a New Holland 450 sickle mower that I use on food plots. Yesterday the bar broke at the end of the head on the hole for the 4th section. I see there are splicing kits but because of where the break is at I can't use a 2 piece like a lickity split. . The first 2 rivets on the head are unique to the bar. So removing a couple sections and sliding the long piece onto the nead isn't going to work. Even if I removed all the sections the ends aren't the same so that won't work either. I know welding is an option but it looks like the sections should be removed to get the bar flat & stright and then be welded to the section at the break. Correct? Short of finding a donor bar to splice or buying a new one, anyone have any ideas? Thanks y'all.

Sounds like the "knife back" broke, if the actual bar broke you'd have larger problems, LOL! Move the "knife back" over to the left and drill some holes as needed to put the "head" back on, then weld the broken off piece on at the far end where the weld will be under a lot less stress. Will probably have to drill a couple of holes there, as well.

Or, have you priced a new aftermarket knife at a farm store or from WEBB Cutting Components on the 'net?

 

[wore out]

Welcome to YT forums. You solved your issue but didn't recognize it. Do take the few involved sections off and drive bracket. The take it to a professional welder for a fix. (with the sections taken out so the repair person can make all spaces correct. Not a big issue. Make sure all guides and clips are to manual specifications to avoid a repeated stress failure. Jim

Sounds like a plan 'cept for the fact that a "professional welder" will likely charge half or more of the cost of a new knife.

Unless his knife sections are in really good condition a new knife likely would be a good in investment. IF the sections are worn/ not in good condition that may have contributed to the knife back breaking

 

[DanielW]

Sounds like you have a broken knife back, not a broken bar. Very common, especially around here in the Canadian shield where everything's so rough and rocky and gets beat to heck. Often caused when a section works loose, angles up, and jams between guards. Welding is the typical method to fix one, and oodles of knives have been welded over the years (some of my grandfathers' knives had broken and been re-welded in so many places there was more weld than original metal - or so it seemed).

Unfortunately they always break at a rivet hole, and to get a strong weld it's best to cut it back further and weld between rivet holes (use a section to hold the rivet hole spacing correct) . It's handy to have an old donor knife you can cut pieces out of. Admittedly, lots of rush fixes have been done by welding the original pieces back together at the break location, then grinding flat and drilling out the rivet hole in the weld. Not really proper, but when you need hay down in a hurry, you have to work with what time allows.

Yes, you will have to remove sections in the weld/break area. But if you're going to own/use a sickle mower, replacing sections is something you're going to get pretty good/quick at regardless. While you have the knife out, be sure to check for other sections that are working loose. Best to go along and tap them with a hammer. A section will rattle and not feel as solid if it's loose.

You don't need to have the best welder in the world do it. Anyone moderately good at welding should be able to do it just fine. Vee out the mating halves to get a nice weld prep root so you get full penetration, weld all around, let it cool slowly, and grind flat. The knife backs are just mild steel, so nothing fancy required to weld. I'd advocate for Mig (real Mig with shielding gas, not flux-core nonsense) as it's going to have the least chance of porosity into he weld: Porosity is a killer with any cyclical/fatigue loading condition.

But if it's an old/worn knife, money spent on a new under-serrated knife is some of the best money you'll ever spend. I wouldn't buy a genuine NH one. AI sells aftermarket knives for that mower that will cost much less and be just as good. And any dealer or farm supply can order from AI.

 

[Freewheelin]

Thanks y'all. I couldn't find the correct nomanclature so I appreciate the "knife back". I did find that a new one is not that expensive so I ordered one. I have a good friend who is an excellant welder so I'll have the broken one fixed for a backup since it's in good shape. Thanks for the tips. Funny thing is that we farmed sand country and I don't remember ever breaking one. Of course, my Dad was a stickler for checking everything before hitting the field. It broke because I was in a hurry and didn't check the sections.

 

[BarnyardEngineering]

You mean to tell me that for 40 years I've thought that the BAR that the SICKLE sections were riveted to was the SICKLE BAR and it's actually the "knife back?"

Which piece is the sickle bar then?

 

[jwal10]

To me sickle bar is the whole thing, head, back and sections with rivets. Each can be ordered separate or all put together....James

 

[DanielW]

You mean to tell me that for 40 years I've thought that the BAR that the SICKLE sections were riveted to was the SICKLE BAR and it's actually the "knife back?"

Which piece is the sickle bar then?

Everyone I know calls the 'bar' the main bar that the guards bolt to. The knife is the moving component consisting of the knife back, sections, and ball/end joint (depending on what style wobble mechanism it has) - sometimes called the 'sickle assembly' as well. That's the way the parts manuals and websites refer to it as well. But I'm sure nomenclature changes from place to place and there's probably no right/wrong answer.

 

[Fritz Maurer]

When you have the broken one fixed, weld it through the rivet hole and drill it out again. Then weld 2 or 3 sections together on either side of the weld at the joint where they butt together. This will spread the load out without adding any more welding stresses to the knife back.

 

[rustred]

I have a New Holland 450 sickle mower that I use on food plots. Yesterday the bar broke at the end of the head on the hole for the 4th section. I see there are splicing kits but because of where the break is at I can't use a 2 piece like a lickity split. . The first 2 rivets on the head are unique to the bar. So removing a couple sections and sliding the long piece onto the nead isn't going to work. Even if I removed all the sections the ends aren't the same so that won't work either. I know welding is an option but it looks like the sections should be removed to get the bar flat & stright and then be welded to the section at the break. Correct? Short of finding a donor bar to splice or buying a new one, anyone have any ideas? Thanks y'all.

without seeing the actual break . i welded one up on my brothers versatile swather. just removed a couple sections. and welded it up hole and all,with lots of peening as thats were it broke. then after regrind it to shape and redrill your section hole. its still holdng. a picture explains things better , as to a yes or no situation.

 

[rustred]

around here its just called a sickle. for example i need to replace the sickle. meaning pull out the old one and slide the new one in.

 

[560Dennis]

We weld sickle bars up on the new idea we have ,it happens , been going 40 years

 

[caterpillar guy]

Get one with bolts instead of those rivets it will be a much happier experience for you. Just take the guard off change section and replace guard back to work. Also the guards if worn at the edge where the sections slide through is worn rounded under the knife section it will cause broken bars as they don't cut good either and check the wear plates in there as well as the hold downs if thew knife can ride up off the guard it will plug rather than cut.