Swhitching Cat. II to cat. I

Had a guy tell me I could have his old three point blade the other day.  He replaced it with one that swings with hydraulics.  I went to look at it and it has category II lift arm pins.  I only have category I arms.  I have a set of Cat I pins I can steal out of something else to get it home with, but are the threaded ends of cat I and cat II pins the same size?  Or will they be too small and leave it with slack in the holes?  My coffee isn't making me alert today, just shaky so I hope this makes sense. 

you can buy what ever size cat I pins you need, or you can buy adapters for it. there is an andapter made (found at about any farm store) that will slide onto the cat II pins, and on the other end has the cat I pin for your tractor.

Checking Baum Hydraulics catalog section C, the threads for category 1 are 7/8" like the pin diameter, and category 2 threads are 1-1/8" like the pin diameter. I don't see an adapter or special pin to fit a category two hole and supply a category one pin. But there is one to fit a category 1 hole and provide a category 2 pin. It would be great if that is what is in the blade. There are 7/8 to 1-1/8" sleeves, too long for the threads but can be sawed shorter to bush the large holes for the smaller pins. Need sturdy flat washers to finish that adaption. Two per pin. Baum also has a pin with 1" threads that is double ended with 7/8" pin on one end and 1-1/8" pin on the other end.

Bomgaars and Theisens and other farm stores should have similar parts on hand. As well as farm equipment dealers.

Decades ago I made category one lift pins to fit category two mounts for a JD row cultivator and for a rotary hoe using steel stock and my metal lathe. Worked the cat 1 tractor hard but didn't break anything.

Gerald J.

Okay, I figured somebody probably made what I needed.  I was looking at the shelf at the local Orchlens and didn't see what I needed.  I forgot about the width but I can turn them to the inside and probably get by.  We've got a two bottom plow, not sure what kind.  It's cat. I but the pins were wider than standard cat I pins.  We had to take one lift arm off the little tractor to get it hooked up.