# New Holland BR7000 series net brake problem



## Gearclash (Nov 25, 2010)

Question for mike10, was there an official NH fix for the net brake being quite tight on a full roll of net, but not braking enough on a near empty roll? Never had a problem with this on my 7090 till this year, then suddenly the net wouldn't start wrapping because the tail was almost nonexistent. Had to back the brake off and lengthen the knife arm linkage to get everything happy again.


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## Beav (Feb 14, 2016)

Had similar problem with our 7060 it was not the brake, had to replace the grip blades for the net wrap roll


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## mike10 (May 29, 2011)

On the 7000 balers NH increased the amount of brake pressure being applied. The vast majority of balers will not have an issue, but occasionly I will run into one where it is an issue.

If I have a problem baler, I have a ring the same diameter of an empty net roll cardboard tube. I place this ring on the net support rod and under the counter roller and adjust the brake so there is lite drag when turning the brake drum.

The tension on the net roll increases as the net roll gets smaller. If the gripper plates are bent down or loose the increased tension will strip out the cardboard tube and you will loose braking action. The net will still cut, but you will end up with a ragged cut. You will also get an occasional bale which is not wrapped to the edge.

When removing the used up net cardboard tube, engage the lock and rotate the tube while pulling the tube off the support rod. Just pulling the tube straight out without rotating will damage the grpper plates. If you can pull the tube off without rotating the tube then you need to check the gripper plates for damage.

You also need to check the gap between the baffle and duckbill. The baffle is the bottom plate of the opening you stuff the net into. The baffle should make light contact against the duckbill. There should be no gap except at each end. If you have a gap the net will pop back up the duckbill.

Lenghtening the knife linkage should not have had any effect, but if it works. I would be a little concerned about the bearing, on the knife linkage, which rides in the slot of the duckbill being hammered out by hitting the top of the duckbill slot. Did you adjust this linkage or the brake linkage?

When I hear the type of issue you have and the baler has not had a problem in the past, I look first at the gap of the baffle and the condition of the gripper plates.


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## Gearclash (Nov 25, 2010)

I can't slip the net tube on the grippers so i doubt that is the problem.

The first problem I had when this baler would't wrap was actually that there was too much gap in the duckbill. Near as I could tell the net tail had hooked something during insertion and bent the angle on the baffle just enough that it was impossible to adjust it to spec. Had to remove the baffle and gently bend it using two pieces of angle steel and a vise. After that, even with the baffle touching pretty firmly in the middle there would be insufficient tail to start the wrapping process. I adjusted both the net brake spring linkage and the knife trip linkage. Adjusting the brake had little effect. Adjusting the knife linkage did. I will take a look at that follower bearing!


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## Gearclash (Nov 25, 2010)

The knife linkage follower bearing is in splendid working order . . .


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## mike10 (May 29, 2011)

Once there is a gap between the baffle and the duckbill dirt packs in around the upper mounting angle so trying to adjust the baffle will not work until the baffle is removed and the dirt cleaned out. There usually is not that much dirt, but enough where the baffle can not pivot up when the nuts are tightened.

As long as the bearing is not contacting the top of the slot in the duckbill you are ok.

If you have too much drag on a full roll of net, you will have even more drag as the roll shrinks. As the net is used up the brake spring tension is decreased and you be would be correct to think the brake spring apples less pressure to the brake. However, another force is in play along with the spring tension applied to the net. That force is leverage. The bigger diameter of the roll there is more leverage to pull the net. As the roll shrinks there is less leverage so it take more force to rotate the roll of net. This is not just a theory. On the new Roll Belt balers when they first came out we had issues of the duckbill stalling when the roll of net got to small. On the new balers the duckbill does not stop at a precut position but continues to the home position. The duckbill would stall before the duckbill would return to the home position because of the load. The system would work fine until the roll of net got small. To confirm my theory I took a baler that we installed the updates to and did the net pull test. I removed the customers small roll of net and installed a new roll. I adjusted the brake so it took 85 lbs pull to unroll the net. I then installed the customers small roll and checked what force was required to pull the net. It took 95 lbs of force to pull the net.

So what does this say about your situation? It indicates either the spring was loosened too far and thus no braking when the roll got smaller, or the cardboard tube was stripped and thus no braking action was being applied to the net.

To check if the cardboard tube is stripped out rotate the tube in the direction the tube rotates when the net is being applied. If the brake disc does not turn with the tube then the tube is stripped out. A stripped tube is harder to remove than one that is not because a depression is cut out of the tube and traps the gripper plates. Another way is to check how the net is being cut. If the net is cut cleanly then the brake is working. If the cut is ragged then the tube is stripped.

I had a customer who wanted to run black net and we could not get the tail to remain in the duckbill. As you know the end of the baffle has teeth. I welded closed every fourth opening of the teeth so the baffle would have more surface contact with the duckbill. I also did that to one other baler that was causing problems. That took care of both balers.

The next time you change net rolls and have an empty tube on the net support pipe, see if you have any brake drag with the counter roll on the empty tube.

Which way did you adjust the knife linkage? Did you lower the bearing or raise the bearing?

I do not argue with success but I like to understand why a particular adjustment would work..


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## Gearclash (Nov 25, 2010)

> Once there is a gap between the baffle and the duckbill dirt packs in around the upper mounting angle so trying to adjust the baffle will not work until the baffle is removed and the dirt cleaned out. There usually is not that much dirt, but enough where the baffle can not pivot up when the nuts are tightened.


Dirt is certainly a possibility, but the baler went from working fine to not at all with after a net roll change.



> If you have too much drag on a full roll of net, you will have even more drag as the roll shrinks


On a 7090? I would beg to differ. I thought the brake tension was pretty high (checked by turning a full roll of net) so I reduced it. When the roll of net was nearly gone, there was less than zero brake tension. That causes problems! So turned the brake bad up.



> Which way did you adjust the knife linkage? Did you lower the bearing or raise the bearing?


Raised the bearing. This would have the effect of retarding the timing of the net knife tripping, which would mean the duckbill would be farther away from the knife when the knife does trip. Presto, we had a 4" long tail.



> I do not argue with success but I like to understand why a particular adjustment would work


Agreed! And I am always looking for causation when problems do occur.


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## mike10 (May 29, 2011)

Just a couple of notes.

If you have a spring scales you can check for yourself the force required to pull the net with the brake applied. Latch the taligate in the open positon, Insert the duckbill, pull about 6 ft of net out the back of the baler, return the duckbill to the precut position so the brake is fully applied, tie a not in the end of the net coming out the back of the baler, attrach the spring scales into the knot, pull on the spring scales and check the pounds of pull required to pull the net through the duckbill. The initial force required to start the net turning will be higher then after the roll starts to turn, you want to use the moving reading. Now, if you have no brake spring pressure when the roll is small then your results will not be accurate.

As I said, the lack of braking on a small roll was either casued by the spring being adjusted too loose, which appears to be what you had, or the cardboard tube was stripped. If you want the minimum amount of braking adjust the brake spring as I said. With an empty cardboard tube on the net support rod, adjust the brake spring so there is still a slight drag on the brake disc. I have also used the procedure used on previous BR models to set the brake spring on the 7000 series balers.

The knife linkage is adjusted so the roller clears the top of the slot by 1/16" when the duckbill is in the home position.  If you were able to raise the link and still have this gap between the duckbill and roller in the home position, then your link was out of adjustment. I can see where this would help if the knife was tripping prematurely, I have checked at what point of duckbill travel the knife trips and the knife trips, when properly adjusted, slightly before the duckbill reaches the home positon. If you raised the roller too far the knife would not fully close and as I said would put a large amount of stress on the bearing when it hit the top of the duckbill slot.

In the end, all that matters is the baler is working.


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## Gearclash (Nov 25, 2010)

I did some checking and adjusting this morning. Using a nearly empty roll of net, as in not enough net to wrap another bale, I fiddled with the brake drag until I had about 40-50 lbs pull. This was pulling straight out the front of the baler, no other frictions involved. I thought this was enough drag to keep things under control. With a near full roll of net I had an astounding 80-90 lbs pull with the same brake setting. That's asking a lot of the net tail . . .

Another thing I noticed, the spring on the brake is so stiff that the initial spring rate on a near empty roll is really the torsional twist of the shaft going across to the net meter roller.

In case it matters this is an early 7090, sn Y7N03881.


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## mike10 (May 29, 2011)

The recommended setting is 85 to 95 lbs pull out the back of the baler. To get an accurate reading you do need to go out the back of the baler because of the difference in the leverage it takes to rotate the roll of net through the rest of the system. If I had to guess you still have too much tension on the spring, but I never have checked the pull out the front so I could be wrong.

What I have found is the BR balers will wrap very well with very little tension on the net. Why NH decided to change to high net pull, I do not know. On the prior model BR balers the brake force was checked using an inch pound torque wrench. With a empty cardboard tube on the net support, you would put a 5/8" bolt in one of the holes where the latch that holds the brake disc for removal of the tube and turn the brake disc so the bolt was straight down. Taking an inch pound torque wrench so the torque wrench was 90 degrees to the net support rod, you would chewck at what point the brake disc would turn. On those balers the recommended torque required to rotate the disc was @ 120 in-lbs. When I check the BR balers the setting is 150 in-lbs plus.

As I said earlier, the BR takes very little brake force to wrap properly. If I have a problem baler I will place my dougnut under the counter roll and adjust the spring so there is just a small amount of drag on the brake disc. My doughnut is a ring I had machined that will slide on the net support rod and is the same diameter of an empty net tube.

If you do not see the net sag or the net roll continue to roll slightly when the net is cut, then you have enoough tension.


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## Gearclash (Nov 25, 2010)

An update to the saga. I had everything adjusted to work ok with 7000 ft net rolls. Then we ended up using most of a pallet of 8000 ft rolls, and the problem of the tail being too short to start wrapping came back. With the 8000 ft rolls, it was often necessary to back off the net brake at the beginning of the roll and increase the braking when the roll was nearly gone. Hopefully I have some time this winter to look into this more. Also hopefully the 7090 will find a new home by next baling season. I have had 10 fold the trouble with that baler compared to the old faithful 780A.


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## mlappin (Jun 25, 2009)

Strange, guess I've got lucky. Had a 644 in the past and now BR740A, went thru both upon purchase, adjusted per the manual, did a little tweaking after that and have had mostly zero issues with both.

A cousin bought a BR7060 and has already swapped the net for the twine actuator as the net one went bad, then the one on the net from the twine went bad, then he had to buy a new one. From my understanding, NH doesn't give em away considering something very similar can be had from Burdens Surplus Center for considerably less.


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## Gearclash (Nov 25, 2010)

I'm running the 780A and the 7090 side by side so it really burns me when the 7090 is stopped (again!). 780A mighta turned over 20K bales yesterday, 7090 has 8.2K.


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## endrow (Dec 15, 2011)

We have a br7060 8.5 KN bails from new. I am going to agree that the performance on the machine is good net wrapping works perfectly but the manufacturing of shafts and things like that New Holland is just going to cheap. , the big shift on the outside of the coupler opposite the main gearbox snapped off clean break right at the bearing. Sure to a guy who's an engineer and machinist alhis life. And he said poorly manufactured poor quality metal. I replace the shaft and the coupler, 900 Bales later tore splines right off the shaft. Dealership showed shaft to New Holland they said did not have the coupler and gearbox align properly. I showed it to sevraeral machinist and they said Vision cheap Steel . One piece of equipment like that I fully understand if a bearing or a belt or a blade or how do you have your ware items fail. What's causing me to lose interest in this piece every other time something breaks at $500 to $800.


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## mike10 (May 29, 2011)

It definately sounds like the parts are not in alignment and both failures are related. If you can not easily move the coupler back and forth between the gearbox shaft and the outer shaft you have an alignment problem and yes you will fail shafts, spines and bearings. A fatigued shaft will appear defective because of the flexing. What you see on the splines is a wave pattern of wear. Looking down one of the splines you will see high wear gradually moving to an area of less wear and then back to high wear.

When installing a gearbox, no matter what brand or type of equipment, I always make sure the couplers are aligned because, as you found out, it does not take long to fail the spines.

That is not to say you may have had a bad shaft but it is not an area I would be concerned about if everything else is where it needs to be.


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## Gearclash (Nov 25, 2010)

This is a picture of my first effort to correct the net brake tension on my BR7090.









Moved the spring down on the counter roll arm so as to get a more linear braking pressure, and a tab to drop the adjuster on the brake lever to maintain the alignment of the adjuster and to allow for a little more pull on the spring without increasing the brake drag. Pull as shown on a scale is now about the same for a near full roll as an empty roll. Hopefully I get to field test this next week.


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## mike10 (May 29, 2011)

I would be curious as to how it compares to the the 780s tension wise. Over the weekend I am planning on adding a post to my NH repair thread on net spreading problems. In that post will be information on how to check the net brake using a torque wrench on the brake disc. This will measure the actual force to turn the disc with an empty net roll tube. I would think if you adjust the 7090 to the same reading as the 780s you will not have any issue.


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## Gearclash (Nov 25, 2010)

Near empty roll on 780A takes roughly 40 lbs pull on the net, roll with 6-7,000 feet on it take about 10 lbs more pull. I have never messed with the net brake on this baler in 10 years/18500 bales.


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