in my opinion no. u have to sharpen them more often to keep the edge,and they dont shear across the shearbar like the 491/492 knives do. its almost like they pinch the material instead of cut it.
as far as the sharpening more often i relise on a 980 compared to a 960 you are going to have to sharpen more,but im comparing a 900 to a 960 or 950 now that claas has changed all the hp ratings again.

 

Interesting observation my friend, I know you spend a lot of time inside of these machines....your opinion carries alot of weight, thanks for the input !

 

As far as cutting I do not think they are as good. We have a hard time getting all of the hardfaced edge used up, you cant set the knives back out after they are half gone.

We had some crack and fly out too. That was expensive but claas finally took care of it.

Throwing ability is a whole different issue. I wonder if you really would have to have the accelarator for corn. These knives can really throw the crop well, which I think frees up some of the parts that follow in crop flow.

 

O.K. , so the older knives are as good as if not better than the new knives in some cases. But throwing ability ? really ? How is that determined, cutter cylinders are both rotating at the same speed. Just trying to validate the differences, and thanks for the feedback joblo.

 

Because the knives have the curve it allows them to cup and throw with less crop coming back around and being relased to the crop flow.

The original krone blower paddles were that style of design and were by far superior than flat paddles at throwing the crop out and not carrying feed around.

How much can you throw with your hand cupped verses perfectly flat. Quite a bit of difference.

 

i to have had some crack,fortunatly i caught it before major problems.
they(claas) have updated the arms that make anvil pivot on the newer machines which allows the shearbar to travel further and use more knife.

 

I will agree with you on the fact the flat knife is a better choice. But, this idea you have that a curved knife is going to RELEASE the crop better than a flat knife....Ain't buyin' it. Is it just speculation? opinion? or fact? Did someone from Claas tell you that this condition exists? "Inquiring minds want to know", and besides, why would Claas make that drum for over a decade if there was a recirculation problem?

In MY opinion, Claas didn't make it better....they just made it different.

I guess the real question is " why did Claas find it necessary to make the curved knife? "

 

my opinion of the diff/new knife is because the compepetors are catching up,and r&d deceided they needed something new to stay ahead.
would be interesting to see what a 980 with the old style knife drum would do compared to this new style. ik a 900 and 960 with run side by side speed wise,not sure on tonnage.
and that cupped knife design is not new,look up some very old literature on allis chalmers pull type choppers,they use the same cupped knife design.

 

I think that in the future we will see some unexpected changes.

 

As for readjusting the knifes. You can see it also from the other side ,that you do not need to pull them out!?

 

Come on guys, we all know this design was a step towards a open center drum that would allow for a longer length of cut for some biomass crops. Problem was the open drum was junk. I personally have no knowledge of these knifes, just hear some complaining. The idea of the bent knife does make sense because you will have much more metal mass in line with cutting direction. In theory this should increase knife life, obviously this is a false theory. Have not heard anything from you lately, what's been up?

 

The thing that the new claas knife does is allow it to cut a thicker crop mat without having road blocks in the way. The knife drum, the nut bar, all are road blocks in the way of crop flow as it is cut. Think of it as pushing feed up a flight of stairs. Both of those things are stairs that have to be filled in order for feed to make it farther around. I believe that if you put the new knife drum in an older machine and ran in next to a sister machine that the new knife drum would cut more. I also believe that the width of the knife is to great. The 492 had 4 bolts to keep them in place. The 494 have two because of the cup shape of the drum. But this leaves the middle of the knife unsupported causing cracking.

 

Junior, I don't know if any of that makes sense or not. I'm going to examine that concept a little more. FYI....the 492 machines had 4 knife bolts. Thanks for the words of wisdom.

 

I was tired fixed it

 

Junior was thinking about his favorite harvesting machine, the KRONE , with five knife bolts. This is amazing, I agree with everything junior said in his last post. I would add that the old style of knife might not of cracked as often do to the fact it could slide back when it hit a object. New knifes just have to take the abuse.

 

Hello all. Although this is my first post I have followed the forum for quite some time.
We run a claas 970 in Ireland and are having serious issues with the chopping cylinder blades. The machine has completed its 3rd season now. I'm not quite sure what the full part number is but the first 2 seasons we ran .2 and .3 which we were quite pleased with, although this season we have moved on to .4 blades which have been a complete disaster! These latest version are breaking in the middle continuously and wearing out extremely quickly. At the end of the season claas supplied ous with 1312501.0 blades which seem to be fantastic but we are now told that they are not available in the uk and are for the American market. Would it be possible for a member to varify with a claas dealer in America if they are available there. Many thanks. William

 

Is any of you finding that you 492 knifes are not lasting as long as years past

 

Claas knives have been a disappointment for many years, I don't use them any more.

 

We are really happy with our 494 with the v max drum/knives, its a 950 which replaced our 492 890, which more or less are the same hp.
The output of the 950 is noticably more than our old 890 with the old knives which we put down to the knife shape.
Also in very dry condition's where our remaining 492 870 is chopping grass, it blocks between the drum and and accelerator fan. But if we bring in the 950 and it never blocks.
Maybe because the 950 is the baby it doesn't seem to break knives? But we harvest some rough land all sorts of foreign objects going through (we turn off rock stop because we wouldn't get anywhere otherwise)
And also on a side note, the problem we have with the classic drum after 4000 odd hours is on the drum where the 4 bolts bolt the knife onto the drum wears down so much we have to replace the whole drum because the steel wears right down to the holes. Not sure if thats a common problem in other parts of the world but all our soils are volcanic ash which wears everything out. But you dont have that problem with the v max the bolting points are protected.

Just my opinion from down here in little old New Zealand.

 

Wearing out knife ledges is common is some areas of the US. That problem is solved by putting on drum covers that were dreamed up by some cutters in California. Thin piece of AR steel bent in L shape with holes to match bolt pattern. Goes above nut bar and covers leading edge of knife ledge. Krone has added a single pass of hard surface to leading edge of latest machine. I think it needs a second pass to cover complete front edge.

 

Kiwichopper I'd like you to come back to me after 4000hrs on the 950 and then tell me which is cheaper. I'd say you'll find that the v max drum is very costly to run

 

so far the 494 knives do not last as long as 492 in my experince. used to be able to get 400 hrs on a set of 492 knives in an 870 sized machine,can only get about 200hrs out of a 940

 

200 hours? wow what are we doing different? Our knives which came with the machine have done 300 chop hours maize chopping and 200 hours with half of those knives chopping grass and we are just about to put a new set in for our next maize harvest? Maybe our length of cut is far different? 11-15 in maize and 21-25 in grass.
It is a bit of bummer that when we put a full set of knives back in we have to put in a new set because you cant move the knives like the classics. So I guess when you break 1 you have to grind it down to the same level as the remaining knives on the drum?

 

I have a 960 here that got 310 hrs out of a set of knives over the season. If I am only going to get one season out of these new knives, I would much rather have the original style knives. They work good and are less expensive. Why would you pay four times the price for the same quality and performance ?

 

the 494 knives just dont stay sharp like the 492 knives. so u have to sharpen them more,so u wear them out faster. claas has changed the design of this new knife three or four times i belive.