Cat 1 Dimensions

[ch47dpilot]

Can anyone tell me why my CAT 1 attachments lower link points are different dimensions. I have a King Kutter 5' rotary cutter, 6' finish mower and 6' Blade. Also have a 5' box blade and 6' yard rake from other companies. The inside pin dimensions vary from approximately 24" to as much as 27". For my Rotary cutter I actually had to put the pins on the inside of the lift arms or they would have been closer to 29" apart. This isn't a big issue, I have the TSC version of the Pat's easy change system, but I don't see how a quick hitch would work for everything I own. What are the correct dimensions for pin to pin on a CAT 1 (research looks like 26-27") and has anyone else ran into this problem? If so how did you fix it, longer lift pins??.

 

[jeff9366]

Harry Ferguson, inventor of the Three Point Hitch, determined the "standard" width of the Lower Links; 26", in the 1930's.

During the 1980's, with the continued development of suburbs, lighter "residential" tractors entered the tractor market, promoted foremost by Kubota. Lighter tractors have reduced Three Poiint Hitch dimensions. The width of some subcompact tractor Category 0/I Lower Links is 20".

 

[Wagtail]

This may help:

 

[RandyT]

I have the same issue with my Rhino finish mower, King Kutter disc and Rural King brand rotary cutter. Three different pin spacing. My finish mower is close to the standard 26" spacing, but my rotary cutter is real close to a 32" spacing. My lower link maximum spread is 37" and the pin tips on that rotary cutter clear the links by about 1/4 on each side when attaching and detaching. So the working pin distance on my cutter is a little closer to 32" than it is the standard Cat 1 26" Seems like I came across something a few months or years ago that talked about Cat 1 comes in 20" width, 26" width and 32" width to divide the small Cat 1 tractors from the larger Cat 1 tractors.

 

[KennyG]

Seems like I came across something a few months or years ago that talked about Cat 1 comes in 20" width, 26" width and 32" width to divide the small Cat 1 tractors from the larger Cat 1 tractors.

As shown in the chart above, 20" width is Cat 0 and 32" would be Cat 2. If the pins an be mounted inside or outside, it's usually an attempt to make an implement both Cat 1 and Cat 2 compatible. With conventional three point systems, the flexibility of the lower arms position can make up for a lot of sloppiness in how the implement is built. With quick hitches, not so much.

 

[bcp]

Before quick hitches, dimensions that varied a few inches didn't matter much, if any. I've always suspected one reason manufacturers changed things an inch or two was to reduce scrap.

Bruce

 

[kthompson]

On the farm style tractor there use to be plenty of open room for the lift arms and stabilizers and as such the width of the implement was not near the issue it is today. First place in my knowledge it made a difference was with Ford 601 as they used fix length stabilizers, so the width got important but still today think you will find some variance.
Honestly do not remember there being any width issue in the true farming implements but have noticed it more with the use of cutters, rakes and other such implements. Now that is all based upon my limited experience. Also as Cat 2 and Cat 1 will bleed over between each other and no doubt Cat 0 and Cat 1 it gets to be more of an issue I think.

 

[ch47dpilot]

Anyone see an issue with installing longer pins. I know the longer pin will put stress on the attachment's lift arm but don't think 1+inches on each side would that big an issue. The only thing I have that I can't figure a better solution than longer pins is my finish mower. The 24" width along with the easy change system I have makes it almost impossible to connect. The tractors lift arms are at such an angle it binds on the pin"

 

[jeff9366]

In my experience long pins oriented inward need to be watched. They loosen no matter how tightly torqued manually.

 

[davedj1]

This may help:

I don't think this is accurate any more. Recently I was looking for dimensions and every single piece of used and new equipment was different. I just picked a middle of the road dimension for my winch build.