disc harrow - number of blades question

[RoughneckDave]

what is the best system for cutting

18 blades, 20 blades, or more?

seen some with 8 on front, 10 on back - any advantage to this setup?

also what about size of disc, 18,20,22 in


dave

 

[Greyfields]

The rule of thumb I've heard for discs is 4 HP (PTO) per foot of width; which isn't exactly the answer to your question but a good rule to know. So if you have a 40 HP (PTO) tractor, you can pull a 10' set of discs.

I have one set of 6' wide 3-pt attached discs and a 10' set of drawn discs (weighs ~ 2500 lbs). There is no doubt the heavier drawn discs cut harder than the 3-pt because of the weight difference.

I have no idea if the size of the disc itself matters. I can't envision why it would. The biggest thing I've found about discs is getting a set with blade scrapers on it, so turf never gets jammed between the discs and frame. That's a pain to constantly stop and have to clean the discs up.

Oh, one more thing. For my soil and climate, serated discs are a must.

 

[kbotaman]

Spacing between the blades is a major factor in how well the disk will cut the ground, the wider the space between the blades the better it will cut. On the down side the wider spacing does not do as good of a job finishing the ground. Another factor in how well a disk will preform is the type of soil you have.

 

[MtnViewRanch]

I have no idea if the size of the disc itself matters. I can't envision why it would.

The taller the disk, the deeper that it can cut. The deeper that it cuts, the more soil that it moves. The more soil that you move, the more horse power that you need.

 

[MtnViewRanch]

what is the best system for cutting

18 blades, 20 blades, or more?

seen some with 8 on front, 10 on back - any advantage to this setup?

also what about size of disc, 18,20,22 in


dave

Dave, welcome to TBN. We need more info to really be able to help you. What size tractor do you have, how much land will you be disking? Do you want a 3 point disk, or a drag type disk? Just to give you an example, do you need a 4' wide 3 point disk for your 18 HP sub cut to disk an acre or are you looking for a 60' wide disk to pull behind your 450HP tractor so that you can disk your 1000's of acres. Just two of the extremes and I'm sure that you are some were in between.

 

[BTDT]

Here is an interesting idea. I've never seen one work, and it may just be more trouble than it's worth (and I don't know what it's worth or how much it costs). Sorry for the bad pic in pdf. attachment, but you can see it better in the link to site. As some have said, your soil conditions will play a part.


Link to site tytaninternational

 

[JoeinTX]

I've seen this "rotary" plow before (maybe from this same company, not sure) but like you I'm not sure of its usefulness. I'm not sure what the application of PTO power to the discs actually does when a disc plow's effectiveness is in its weight and disc spacing.........gravity does the rest.

Case in point the large Rhome and FECO trailed discs, designed intentionally for cutting roots and growth in land clearing, are heavy, narrow, and use wide spacing disc gangs to penetrate as deep as possible. Applying PTO power to them would seem to add little to their effectiveness.

This thing is not a tiller.........it's not a harrow........and I would suspect that if you used it without even hooking-up the PTO to it that it would probably perform in similar ways.

A poster above answered the original question.........if you want a ground-prepping tool then you need to go with a plow that has narrower disc spacing. If you want a primary tillage tool, go with the plow that is heavier and has wider disc spacing and preferrably notched-discs.

 

[N80]

So:

1) The wider the disk the more you get disked per pass but the more hp you need.

2) The closer the disks are spaced, the better it works as a harrow and more hp it requires.

3) The wider the disks are spaced the better it works at tilling and maybe requires less hp (but maybe not since it may dig in more).

3) The larger the diameter the disks the deeper it cuts but the more hp you need.

Still makes it hard to know what to get for a first time buyer.

 

[RoughneckDave]

mf 243 ~50 hp

so a 6, 6 1/2 3pt disc for foodplots mostly

ground thats already been broken before mostly


dave

 

[SCDolphin]

I have a Kubota L5240 HST (50hp) and pull a tuffline 61/2 disc with the 22' scalloped blades. I added the optional "covering disc which stick out an extra 6" on each side. I pull in 4wd o trouble but spin if in 2wd sometimes. I run loaded tires and 400lb of wheel weights. I could probaby pull a wider disc but you also need some speed with your pull and I really am not wanting to load my tractor a lot. I like that the disc almost match the tractor's width.