6m 750a changing offset

[Feldspar]

A lot of our winter cereals are out the ground and I am very pleased to see that we now have nicely matching up rows (which are also much straighter than before) over most of the areas that I've looked at. A few small bits where the drill is off a bit, but overall very pleased. Thanks to Ben Burgess and John Deere for sorting out the problem. Gave me a lot of grief looking at the those bloody gaps last year so pleased to have a nice even crop to look at. Thanks for all the advice on this thread too.

 

[Feldspar]

Famous last words! I really am committing some facepalm errors at the moment. First lot of barley emerging gave a rather false impression. Have been right round everything today and I would say we have a lot of fields with uneven gaps in. Doesn't look so bad where we drilled every other pass and then threaded back through because then the problem only occurs every 24m. I think because of the straight lines the human eye is very good accentuating the difference, but that's not an excuse. I would say the problem seems to be more consistent which means it's more our fault as we should be able to correct a systematic error. We did check a number of times the tracking at it seemed spot on. But it can't have been given the gaps we have. I feel very cross with myself for letting this happen again, but I think I was so willing to believe we had totally fixed the problem. It's definitely not as bad as last year, but it's still not even on both sides.

 

[General-Lee]

Famous last words! I really am committing some facepalm errors at the moment. First lot of barley emerging gave a rather false impression. Have been right round everything today and I would say we have a lot of fields with uneven gaps in. Doesn't look so bad where we drilled every other pass and then threaded back through because then the problem only occurs every 24m. I think because of the straight lines the human eye is very good accentuating the difference, but that's not an excuse. I would say the problem seems to be more consistent which means it's more our fault as we should be able to correct a systematic error. We did check a number of times the tracking at it seemed spot on. But it can't have been given the gaps we have. I feel very cross with myself for letting this happen again, but I think I was so willing to believe we had totally fixed the problem. It's definitely not as bad as last year, but it's still not even on both sides.

Do you not colour/shade in as you drill?

 

[Tractor Boy]

Famous last words! I really am committing some facepalm errors at the moment. First lot of barley emerging gave a rather false impression. Have been right round everything today and I would say we have a lot of fields with uneven gaps in. Doesn't look so bad where we drilled every other pass and then threaded back through because then the problem only occurs every 24m. I think because of the straight lines the human eye is very good accentuating the difference, but that's not an excuse. I would say the problem seems to be more consistent which means it's more our fault as we should be able to correct a systematic error. We did check a number of times the tracking at it seemed spot on. But it can't have been given the gaps we have. I feel very cross with myself for letting this happen again, but I think I was so willing to believe we had totally fixed the problem. It's definitely not as bad as last year, but it's still not even on both sides.

With my 4m 750 on Trimble centrepoint I have had to set width to 3.97m and a 5cm offset to the right. Don’t ask me why, there doesn’t seem to be an explanation but at least I think the joints now only seem to range from about 12cm to about 20cm which doesn’t really show up on a whole field scale. I do wonder whether some of my problem is I’m using an ez steer which obviously isn’t going to be as good as integrated steering.

 

[d williams]

A 4m drill is 3.98m wide ( 24x16.6 cm )

Shouldn't it be 4m plus half Coultor width ?

 

[Feldspar]

Do you not colour/shade in as you drill?

What do you mean exactly? Have the coverage map on the screeb which looks fine but the screen only knows what you tell it.

 

[General-Lee]

What do you mean exactly? Have the coverage map on the screeb which looks fine but the screen only knows what you tell it.

Yeah thought you’d see it overlapping and under and I thought about it last night after I posted you're right.
This year I had part of a field where the drill crabbed but only one way, on the screen bouts lined up, watching the drill I could see it was missing a bit.

 

[Daniel]

My Deutz has to have a 55mm offset in the receiver position to track up and down accurately. Don't know why as the receiver is surely bolted on centrally at the factory?

 

[Simon Chiles]

Shouldn't it be 4m plus half Coultor width ?

Row width is 16.6 cm, on a 24 row drill that’s 23x16.6 cm and two half widths of 8.3 cm each side or 24x16.6 which is 3.984 m.

 

[clbarclay]

Row width is 16.6 cm, on a 24 row drill that’s 23x16.6 cm and two half widths of 8.3 cm each side or 24x16.6 which is 3.984 m.

Can the row width be adjusted to 16.667 cm or does the frame restrict widening the rows to a full 4 m?


@Daniel There are a lot of components between a tractors hitch and a receiver. None of which will be absolutely perfect and are all made to specified tolerances, stack up those tolerances and I wouldn't be surprised if a receiver centered on the cab roof was out of line a bit from the hitch point. I would hope it is better than 55 mm, but it may well be technically possible within the design tolerances. Sometimes the specification of items like rubber cab mounts can be rather vague. I presume things like the tilt sensor is calibrated properly?

 

[del_boy]

My Deutz has to have a 55mm offset in the receiver position to track up and down accurately. Don't know why as the receiver is surely bolted on centrally at the factory?

I need a 3cm offset on the reciever on our jd8370r to get it to track back on its same marks. Reciever calibrated regularly and never leaves the tractor

 

[Simon Chiles]

Can the row width be adjusted to 16.667 cm or does the frame restrict widening the rows to a full 4 m?


@Daniel There are a lot of components between a tractors hitch and a receiver. None of which will be absolutely perfect and are all made to specified tolerances, stack up those tolerances and I wouldn't be surprised if a receiver centered on the cab roof was out of line a bit from the hitch point. I would hope it is better than 55 mm, but it may well be technically possible within the design tolerances. Sometimes the specification of items like rubber cab mounts can be rather vague. I presume things like the tilt sensor is calibrated properly?

You couldn’t move the 18 coulters on the 3m fixed centre frame as they are as wide as they can go, you could move the spacing on the three coulters on each of the wings, you’ve either got to poke up with even spaced rows and drill slightly narrower or uneven row width on the wings and drill the full 4 m

 

[Timbo1080]

Well if @Timbo1080 checks his drill and it's all straight, then that makes it less likely it's a geometry. Does make you wonder though, if they can get the wheels that far out, whether there are other geometry issues. Still not sure that would explain why it's wandering.

How many years? Sorry this took so long. Same problem as you. Axles are poorly aligned. Shallow drilling means that more weight is on the transport wheels, so the wandering is exacerbated. Deep, or in loose soil still shows wandering but to a lesser extent. We have managed to get away with it until now, but our Rape kicked me into action, finally. Sorry @Feldspar . The drill seems to have run so far off line, that half of the drilled width has failed, while the other half is fine.....Poor slot closure on one side I guess, or more likely the firming wheel running off line. Hoping that JD will help to pay for the realignment...... A lesson for me in complacency.

 

[Feldspar]

How many years? Sorry this took so long. Same problem as you. Axles are poorly aligned. Shallow drilling means that more weight is on the transport wheels, so the wandering is exacerbated. Deep, or in loose soil still shows wandering but to a lesser extent. We have managed to get away with it until now, but our Rape kicked me into action, finally. Sorry @Feldspar . The drill seems to have run so far off line, that half of the drilled width has failed, while the other half is fine.....Poor slot closure on one side I guess, or more likely the firming wheel running off line. Hoping that JD will help to pay for the realignment......☹ A lesson for me in complacency.

Well our local dealer tried twice to get it straight, but I'm still not sure ours is straight still. We still seem to struggle to get bouts matching up and it really annoys me. To give up and start drilling at less than 6m width would be a real, real pain because now we have a CTF system going that is working nicely except for this. It's such a frustrating fault because I could correct for most things, but this is so variable that unless you fettle it constantly it'll leave gaps. I hadn't thought of going to a specialist wheel alignment place to get it checked.

 

[Timbo1080]

This is very interesting.


Well our local dealer tried twice to get it straight, but I'm still not sure ours is straight still. We still seem to struggle to get bouts matching up and it really annoys me. To give up and start drilling at less than 6m width would be a real, real pain because now we have a CTF system going that is working nicely except for this. It's such a frustrating fault because I could correct for most things, but this is so variable that unless you fettle it constantly it'll leave gaps. I hadn't thought of going to a specialist wheel alignment place to get it checked.

I’m guessing my DTAC will bump into yours in a few days! So sorry that this took so long. Very disappointed to hear that yours is still not right. I’ve been looking at how to go about getting it sorted, and it would certainly be a lot of cutting and welding (Which it seems you have had done, to little avail). The only other solution that I can see is to get a complete chassis.
I tried for a while to find a place to take the drill into, but foolishly didn’t think to ask our local tyre guy - He sent a freelance mobile artic trailer alignment chap out to the farm. Spotted it before he even put the gauges on. How are your tyres wearing?

The muddier tyre is a spare, that only spent about a year on the drill before developing a puncture. The other tyre is showing the worst wear of those that are still on the drill, and the other 3 are all wearing differently again, but fairly well true to the axle alignment issue

 

[Feldspar]

I’m guessing my DTAC will bump into yours in a few days! So sorry that this took so long. Very disappointed to hear that yours is still not right. I’ve been looking at how to go about getting it sorted, and it would certainly be a lot of cutting and welding (Which it seems you have had done, to little avail). The only other solution that I can see is to get a complete chassis.
I tried for a while to find a place to take the drill into, but foolishly didn’t think to ask our local tyre guy - He sent a freelance mobile artic trailer alignment chap out to the farm. Spotted it before he even put the gauges on. How are your tyres wearing?
View attachment 906257View attachment 906258

I'll have another look at our tyres. They did try quite hard the second time to get it fixed, and they did fix the most obvious asymmetry, but it still doesn't behave correctly. Because it's less than 6m we really need to drill straight.

 

[Timbo1080]

I'll have another look at our tyres. They did try quite hard the second time to get it fixed, and they did fix the most obvious asymmetry, but it still doesn't behave correctly. Because it's less than 6m we really need to drill straight.

I dont suppose you'd be able to look up the serial number of the drill, perchance? Just wondering whether they were the same line and perhaps the same jig welder that day.....

 

[Clive]

Our tyres wore unevenly but we didn’t have this offset issue

I put the uneven tyre wear down to them carrying a lot of weight that’s not centred over them well plus a lot of road work

 

[AF Salers]

Running right up to kerbs to avoid oncoming traffic wears the near side tyre badly also in my experience

 

[Simon Chiles]

Running right up to kerbs to avoid oncoming traffic wears the near side tyre badly also in my experience

If you’re going any distance on the road it’s worth taking off the two outside gauge wheels and turning the closing wheel arm around the other way, it’s makes it less than 3m wise on the road and transforms road journeys with one.