Demand for a PT Grapple??

[KentT]

Travis - Kent. I have a small issue to bring up. I know two of us here can attest to this as we both have modified third party equipment to our machines. The angle of the quick attach plate may not be severe enough. As KenT machine is a bit older, this may not apply, but on our newer machinse with built in QA, the plates had to be removed and reinstalled with a gussett behind to create enough downtilt. I can take a picture if that helps, but I would hate to see that lovely grapple arrive and you have to get the QA removed and replaced... Better to get it done at the factory.

It's a known issue to me. The angle on the grapple appears to be about 10 degrees (standard skidsteer QA?), while the PT angle is about 20 degrees. I didn't address it with Travis, since I plan to deal with it with the top/rollover link, if necessary.

 

[KentT]

LOL

Travis was quicker, but I found a better pic from their website...

But, doesn't this limit how much it curls up, but extends how far down it will dump?

My T-8 Howse landscape rake had a vertically mounted plate -- but it was about 24" off the ground -- and it had limited curl upward, but would curl down far, far more than ever needed. The height of the QA plate mounting is certainly a factor, as is the angle. I'm more concerned with the grapple's dump angle than I am with upward curl. But, I have a pin-on top link with two different length positions.

Travis and I discussed the height of the plate off the ground -- I wanted it on that bottom crossbar for strength when pushing into a pile or digging roots, but I did not bring up the issue of angle.

 

[woodlandfarms]

Correct. Ken S and I found out at the same time that neither our Pickle Forks nor our buckets would work properly because we could not get the angle of the dump correct. (Lackender Fabrication was the builder - they did a great job, just PT's are weird). Ken got his first and had to find a local repair. Mine was caught leaving the factory and we got it adjusted.

Also, be careful on the rollover. I use an adjustable arm off of a 3 point that seems to work OK, it is not as beefy as I would like. Why I say watch out is that there is some interference on my machine if I make it too long, hits the arm.

 

[KentT]

The top rollover link on my old 3-pin:

Flickr

I also have an adjustable Cat 1 toplink, so I wasn't concerned about it that much. In fact, I've found the most effective grappling technique is to push into the pile of brush with the bottom of the grapple parallel to the ground, then lift slightly while curling the grapple down so that the weight of the tractor and lift arms push down on the brush, compressing it. Then, close the grapple and crush the brush. Repeat, if necessary. So, I am interested more in curl down, rather than up.

 

[MossRoad]

Yes it would be bad if you could scoop up stuff and then not be able to dump it. As I recall on my 425, the higher you go with the FEL, the more the dump angle increases by itself. And the lower you put the FEL, the less dump angle you have available.

 

[KentT]

I had the same experience, Moss. At full lift, and maximum dump, having dumped, it would not curl the bucket back up (retract the cylinder) until you started lowering the lift arms. Then, it would curl up as normal.

I don't have much bucket experience with this old 1430, mostly mowing, so I'm not sure how it moves through that arc. I do know that the loader arms are significantly different on the new 1430s - the angle of the bends are sharper, and the QA plate/pivot points seem to be a bit closer to the front wheels. Per Terry, swapping to new arms was not an option to get a QA setup, so I didn't compare much farther.

The whole geometry of these PT loader arms is pretty complex, and it would take software modeling (or a smart engineer) to fully illustrate it. For example, the height/distance of the arms on that rollover bar is greater than the distance between the pivot pins on the QA and the point where that top link attaches to the QA plate. So, the loader arms (and their pivot points) do not form a parallelogram with the top link (except at a certain point in curling up and down). Plus, those arms on the rollover bar are moving in an arc all the while. This is nothing like the normal bucket dump/curl on a regular tractor, where the only change is the attachment pivoting on the pivot pins. Now combine that with the arms underneath the rollover bar where the curl/tilt cylinder connects are shorter (at least on the 425) than the arms on top where that top link attaches. One inch of movement from the cylinder does not equate to one inch travel of the toplink - the toplink travel is amplified by the ratio of those different lengths.

 

[MossRoad]

Yeah, I remember learning about the parallelogram and loader arms many years ago here when someone was trying to figure out an auto-leveling bucket that would stay at the same angle to the ground while the FEL arms are raised and lowered. Can't do it in the current configuration, for all the reasons you listed.

Its handy for shaking mud out of the bucket though... WHAM! WHAM! WHAM!!! :laughing:

 

[SpringHollow]

My Cat 1 adjustable top link snapped in two.

Ken

 

[woodlandfarms]

I break one every time I use the back hoe. Now I have a solid piece of 1" steel as a toplink

 

[KentT]

I haven't used my adjustable toplink much to see how strong it is. I used it on the 425 temporarily, while I was getting the original toplink repaired - I broke off one of the welded-on pivots on the ends. Looked like the original Tazewell weld didn't get good penetration. Meanwhile, I did find that the adjustable on did tend to loosen the locknut on the adjusted length. If nothing else, it should be helpful to experiment with, to determine the best location for another hole to be drilled in my solid 3-pin toplink bar, if necessary. I plan to try using the longest hole on that bar as as a starting point, which should give me the most dump, with limited curl...