Sprayer boom widths

[Beefsmith]

We’ve been using a trailed 36m sprayer running on 650’s all year round (tractor also on 650’s). We are thinking of selling the sprayer as it’s now 10 years old. Looking around newish trailed machines have shot up in price making decent used SP’s look attractive again but they all seem to be 24m. If we moved to 24m but left it on 650’s all year round what would the crop loss be compared to 650’s on 36m.
It also means we get a lighter machine which would be good as the seasons seem to be getting wetter and wetter. If we did this it would probably be either an Agribuggy or a Bateman 26. Both 3000l, 24m booms.

 

[Phil P]

I can’t remember which but I’m sure either @Feldspar or @Brisel had a formula for working out crop loss for a given/tramline spacing/tyre size?

 

[Hard Graft]

at 36m with 650 you have 3.61% of the tramline is width is wheeling
24m with 650 it is 5.4%

 

[clbarclay]

Divide total tyre width by sprayer width and times by 100 for % of field that's tramlines

 

[tr250]

Divide total tyre width by sprayer width and times by 100 for % of field that's tramlines

I can’t get that to work my wheels are 380s and 28m tramline how do I work that out?

 

[Chae1]

I can’t get that to work my wheels are 380s and 28m tramline how do I work that out?

28m 380s so 2 x380= 760

0.76/28m = 2.71% as wheelings

Brisel helped me work it out recently.

 

[Brisel]

I can’t remember which but I’m sure either @Feldspar or @Brisel had a formula for working out crop loss for a given/tramline spacing/tyre size?

That was @Rob Holmes. I was asked by someone else recently and made a mess of the maths!

 

[clbarclay]

One tip for maths, start by listing all the things you know in standard units. In this case for example, meters is a convenient unit. We already know the sprayer is 28m, so that's simple. The tyre width isn't in meters though, so convert it from millimetres to meters first.

 

[fermec860]

Looking at it simply 36 m x650 x2=1.3m every tramline. 24 m x 480 x 2=o.960 m every tramline is that any help

 

[Phil P]

That was @Rob Holmes. I was asked by someone else recently and made a mess of the maths!

Thought you may of had a graph for it

 

[Farmer Roy]

pretty simple really

thats the great beauty of the metric system . . .

the maths is so easy, its hardly rocket science

 

[tullah]

If you can't work out the arithmetic on tramlines then how do you cost other stuff about he farm?

 

[Rob Holmes]

That was @Rob Holmes. I was asked by someone else recently and made a mess of the maths!

Don’t think it was me... I’m not that clever

 

[Brisel]

Looking at it simply 36 m x650 x2=1.3m every tramline. 24 m x 480 x 2=o.960 m every tramline is that any help

650 tyres means 1.3/36 = 3.61% of the field. 480 tyres means 0.96/24 = 4%. Put row crops on later in the spring and you gain even more field back.

There's another consideration in output where you might be saving several tramlines in each field by wider booms but the loss of some land where you've got a telegraph pole you can't get behind anymore. You could also lose some forward speed with wider booms. The Chafer trailed I had at my old place wasn't really up to going faster than 12 kph but many spray 24m faster than that. Cost to change, spray efficacy at different speeds, altering water volumes to gain or lose area treated per tank, tank size, daily output, additional weight, who you go to for relief cover if your breaks down etc. All food for thought when considering the change.

 

[Phil P]

650 tyres means 1.3/36 = 3.61% of the field. 480 tyres means 0.96/24 = 4%. Put row crops on later in the spring and you gain even more field back.

There's another consideration in output where you might be saving several tramlines in each field by wider booms but the loss of some land where you've got a telegraph pole you can't get behind anymore. You could also lose some forward speed with wider booms. The Chafer trailed I had at my old place wasn't really up to going faster than 12 kph but many spray 24m faster than that. Cost to change, spray efficacy at different speeds, altering water volumes to gain or lose area treated per tank, tank size, daily output, additional weight, who you go to for relief cover if your breaks down etc. All food for thought when considering the change.

Was there ac calculation for the difference in crop losses form turning as well? I always find you run a lot less crop down running through with the SP rather than the tractor. I know trailed sprayers track a lot better than they use to but still don’t think you can beat just two steering axles.

 

[Brisel]

Was there ac calculation for the difference in crop losses form turning as well? I always find you run a lot less crop down running through with the SP rather than the tractor. I know trailed sprayers track a lot better than they use to but still don’t think you can beat just two steering axles.

No. Turning complicates the simple calculations above. This varies with field shape & size.

You're right about turning circles with trailed machines. A long trailed will run out of lock if turning tight coupled to a shorter wheelbase tractor. You've also got to think about the loops you put in with trailed vs a mounted or 4WS SP where you just back up a bit and turn tight at the ends.

@warksfarmer went from a 4WS SP to a big trailed machine and soon got the hang of the change.

 

[Chae1]

Was there ac calculation for the difference in crop losses form turning as well? I always find you run a lot less crop down running through with the SP rather than the tractor. I know trailed sprayers track a lot better than they use to but still don’t think you can beat just two steering axles.

What if the tractors a fastrac with both axles steering?

 

[Phil P]

What if the tractors a fastrac with both axles steering?

That’s probably the best alternative, I’m sure @Feldspar has gone from a SP down that route so he may be able to give a good comparison?

 

[Bobthebuilder]

If your wanting to run wide tyres all season is it worth putting extra shutoffs on drill compared to extra crop damage, or some people will say don't bother with tramlines and just put wheelings in with sprayer

 

[Brisel]

What if the tractors a fastrac with both axles steering?

Then you'd need an even tighter lock on the trailed, wouldn't you? You'd have one less set of wheelings on the turn vs a front wheel steering tractor though.

Edit: You have a mounted machine, so as good as a SP with that setup. My bad - you were talking about a trailed machine a while ago.