Video Transcript: 

All right everyone Christian from MacDon again.

Today it's time for everybody's favorite chore - knife maintenance. Guards and sections are probably one of the most overlooked and sometimes neglected parts on the header, but it can have one of the biggest effects on your cut quality. We’re going to inspect some of these parts and show you what's good, what's bad, and what's in between. Because of course, we don't necessarily have to replace these every single day, but there is a point where at some point they are going to have to be replaced.

Today we're working on an FD2. We got some: brand new, not  bad, a little bit worse, and horrible. What we've got here is we've got a brand new guard and a brand new section and a properly adjusted hold down. And we're just going to do a little cut comparison. I'm just using a zip tie here. There you can see it sheared it cleanly right off.  there's a nice clean edge right there which is, perfect for, crop that you're going to cut repeatedly. If it's hay, alfalfa and stuff like that, that promotes a good regrowth where a ragged cut can stunt your growth.

On our next section here, we've got a brand new section and we've got a marginally worn guard.  This one still has a little bit of life in it, but it's definitely far from brand new.

Again, the same example. There that did a not bad job. Pretty clean cut, till definitely acceptable. This is a good guard with a worn section. Okay, we were able to achieve, an okay cut quality. What actually happened there is you actually saw the crop, briefly get pulled in between the guard and the section before it actually sheared it off.  It did more of a tear than an actual clean cut. Next scenario is a fairly worn guard, fairly worn section. Let's see how it cuts. There we can see it actually grabbed it, got stuck in between the guard and the section, and it actually tore it more than it actually cut it. You can see the tip of it is bent as well. We're getting worse and worse all the time. Last but not least, a really worn guard and a physically damaged section. Some of you probably got a few of these rolling around on your some of your headers. On these sections right here, you can actually see these little striations going across the top that going to be caused by, improper hold down clearnance. Where now the knife is actually hitting the top part of the guard. Or it gets caused by crop getting basically wedged in between there and going back and forth. Let’s all watch the carnage together. At this point, basically what we're doing is we're just chewing up the crop. We're not really cutting anymore. We're just macerating it until it finally gives up. Imagine that the whole length of your 50ft knife, that's where you're going to get your stalling or you're going to have to reduce your ground speed so much that it's just going to ruin your day.

We've assembled our arsenal of tools here.  We've got the big impact with the 18mm, because I know you're going to use an impact. We got the baby impact with a 10mm. One baby torque wrench for turning their section bolts, some feeler gauges to check the hold down clearance. We've got a new section and a new guard, and a little bit bigger torque wrench for torquing down the guard bolts.

I'm going to put my hand underneath to catch the bolts. That’s one, there's two. Now, with the section lined up between the guard, it's relatively easy to remove here. The bolts will drop out at the bottom. Also on the bottom is your poly, you'll want to inspect that for wear at the same time. This is in good shape, it's basically brand new. And now I can wiggle up my guard, and now that we've got the guard out, we can examine it for actual wear. Obviously this is our cutting edge, and you can see that this is quite worn down. You can see right here where there's a big gap how much it's worn down compared to new. This part of the edge here where we're not doing any cutting is actually still nice and sharp. But unfortunately, there's no guard to cut on that. This is all rounded right over. And this area here is also worn too, it’s actually gotten wider.  This guard is done. Now that's pretty straightforward, but you may not notice on a visual inspection is this back plate right here. This back here or sometimes referred to it as a ledger. You can see how worn that is compared to a new one. As your knife wears as you or as your knife strokes back and forth, this is where the knife head actually wears. And there's always going to be constant pressure going against it because of course you're moving in this direction. It's important that this also gets checked, we're not concerned just about our cutting area, we are also concerned about back here. If this wears completely off what can happen is the knife can actually become dislodged, and it can actually end up going too far back, and it'll actually end up on top of the guards. You're looking at it and they're all down and then all of a sudden the knives are all laying on top.

Now we're going to replace the section. Now notice these little dog bone connectors here, these are installed on the end of the knife closest to the drive end. And these are actually reinforcements, so make sure that you put these back on if you're stripping the whole knife down. Yes. I'm putting a chrome socket on an impact gun, give me your hate in the comments. I'm doing it dirty style. There’s only one 10mm in this entire shop and this is it. Probably have to loosen these ones off a little bit to. All right, goodbye, old section. Hello, new sickle section. Genuine MacDon part. Always the best. Austemempered. Whatever that means.

Austempering is a heat treatment used to form pure B9, a transitional microstructure found between perlite and Martin site. Austempering consists of rapidly cooling the metal part from the austenite…

These are fitted bolts, unlike the, FD1 FlexDraper® and prior series, these don't have to get pressed in,  they just go in from the bottom. There we go. Put your nut on, with the dome of the nut facing down. Normally you would replace all your broken knife sections. All right.

We'll give this a little gentle zap. Now we're going to torque the section. This is 106 inch-pounds or 12 metric something's. I think they're called Newton meters. I've never met him. You can see that that is not very tight at all, that's basically one finger if you're doing it by hand.

Now we install the guard. The hardware is in good shape, so we're going to reuse it.  Those go into our poly and then up from underneath. On this header the hold downs alternate every other guard.  This one doesn't have one. But if it did we would put one on. Quick little blast, wit the impact. Okay, now we're going to torque down the guard. 63 inch pounds? No, that's not right. 63 foot-pounds or 85 metrics or Newton meters. Whatever you prefer.

Okay, in the case where you're replacing a section that's underneath a hold down, you'll want to double check that clearance. Any time you take the hold down off the clearance may change.  again if we had just replaced that one we would double check the torque. And now we'll measure the clearance. We're looking at between .004 and .020´´.  There's quite a bit of clearance there. I'm using a .010´´. I'm basically taking that and splitting it right down the middle. Push down and make sure that it's against the guard. To just to hold down, there's our hold down adjusting bolt. It's a 16mm, I'm sure you've never ever used that one before. Tighten this up, pushes it down. Hold down clearance is also very important because you want to make sure that that knife is cutting against the bottom of that guard. Otherwise, it's like cutting it with a pair of scissors with the hinges too loose.  Basically that's your hinge, if we're talking about a pair of scissors. Push down on it here. Tighter. If we really want it to be push down and make sure that it's against the guard. Fair bit of drag there. Good to go.

Learn more:
FD2 Series FlexDraper® Header, visit our product page.
FD2 PLUS Series FlexDraper® Header, visit our product page.

For additional resources check out our Owners Resources or visit your local MacDon Dealer.