Gotta convert loader to Quick Attach

CanDo · Sep 6, 2016

I've decided it is time upgrade from my old wooden forks that I've used for the past 15 years! (See attached picture of the old wooden one.) They've served me well but since they are stored outside, every year or two I have to replace cracked, worn or rotten bits of 2x in order to keep them in good working order. Additionally, as you can see from the picture, the wooden forks that I built use three 2x10s for the forks to provide some strength which means that I can't pick up a traditional pallet. Finally, I've always been a bit concerned about the real potential of a catastrophic failure that will of course occur at a most inappropriate time.

Anyway, I found a nice old set of 36" forks (for only $50) that, other than a bit of minor surface rust, are in pretty fair shape - the perfect size for my little JD 790. However, I'm going to have to make a carriage for the forks and then of course there is the minor little problem of converting my pin-on bucket to some sort of quick attach. I'm way too old to enjoy horsing attachments around to line up pins!

So, here's the priority list as I see it.

Settle on a design for a quick attach that minimizes the loss of carrying capacity and that is doable with my skill set.
Build the quick attach system and convert bucket over. And if that works, then
Design and build a carriage for the forks using the same quick attach system.

I've read many of the other excellent threads of these types of conversions over the years but any suggestions (keeping in mind the above parameters) or sharing of your personal experiences with your own conversions will be appreciated.

Wish me luck!

zmansmac · Sep 6, 2016

CanDo, I was in exactly the same boat as you a few years ago. I know many members convert to the skidsteer quick attach but that seemed overkill for my little B7500. There are others that have made their own version of a quick attach, and I was one of them. Here is a link to my original build: http://www.tractorbynet.com/forums/build-yourself/244457-did-i-go-overboard-quick.html. In this thread you'll see that I used 2 inch square tube for the cross bar. But later when I upgraded my loader lift cylinders I ended up stressing that cross bar and it failed at the seam. So I replaced it with 2 x 3 inch tube that was a little thicker. I bought a set of 42 inch forks for a $100 and built a simple frame to hold them and work with my quick attach. BTW, for your bucket you only need to put stationary pins in the top holes on each side. Same for any other attachments you make for the loader arms. There is a lot of detail to explain how to line things up to make sure all attachments fit, but you have your bucket as the initial guide. I see you are also in Michigan. If not too far from me send me a PM and I'll be more than happy to spend some time explaining the build in more detail.

CanDo · Sep 7, 2016

Wow! That is certainly nice work!

Like you, I'm not concerned with building a universal QA (like the SSQA) but I am concerned about capacity as I often seem to be trying to lift something that is just a bit too heavy. The JD 790 model 70 loader is already a bit anemic when it comes to payload so I'm looking at maintaining the original geometry by keeping the bucket as close as possible to the original distance from the loader pins and adding as little weight as possible in effecting the change. It looks like your system extends it out about 3 inches which doesn't initially seem to be that much, but it will make some difference and there will also likely be some increased weight added for extra steel. It will all add up!

But then there is also the heavier cross bar (with added toys) that you have used. That's really awesome and is something that I just might have to bite the bullet on. I had thought to use something like a 1" cross bar but obviously that would never be stout enough to do what you've done. Somehow I'll have to figure out the difference in what the weight would be between a 1x1" and 2x3" tube but offhand, it sure does look tempting. Besides being heavy enough to take some extra abuse and keep things in line, it also seems like a practical addition to the functionality of your rig. Like you, I have a receiver on the bucket as well as several hooks. Use them all the time! I can easily see that having the extras on the crossbar will come in handy when the bucket is off. Do you remember the thickness your 2x3" tube?

Whatever I end up doing, I hope it turns out half as nice as yours. Again, verrry nice!

zmansmac · Sep 8, 2016

Thanks for the compliments. I am not an engineer and have no way of calculating the additional lift capacity of my loader after I put in the larger lift cylinders. But I would guess somewhere in the neighborhood of 25-30% more capacity. In my case that would be at least a thousand pounds. And yes, it puts attachments out about 3 inches further but that does not detract much on the overall capacity. I don't know the capacity of your JD but you have to take that into account for sizing the crossbar. If I remember correctly, my tube is 1/4 inch wall. Even in your case I don't believe a 1 x 1 tube will suffice.

You have to realize that the cylinders on each of your loader arms will likely not lift and curl with the same power due to things like internal leakage and such. That differential will put a twisting stress on the crossbar, which is why it needs to be strong. You can look at metal suppliers on line and they will show the weight, usually per foot, of different size tubes. The weight difference of a larger tube is not that much.

Yes, the weight of the quick attach will detract from a payload in your bucket. But for purely lifting things, including pulling out fence posts and small trees and shrubs, etc, you have increased lift capacity because you can easily take the bucket off and use the hooks on the quick attach.

I thought I had a picture of my fork attachment to show you but I don't. Even though my forks are only 6 inches longer than yours, you have a good idea of the weight of each fork. Again, I don't know exact weight numbers, but I can tell you that my framework to hold the 2 forks is less than the weight of one of the forks.

I also have a 6 foot skidsteer snow plow blade that I made an "A" frame for to mount on my quick attach. The plow and frame, including 2 angle cylinders, is over 500 pounds.

P.S. I don't have a receiver on my bucket, only the cross bar. I do have hooks on both though.

CanDo · Sep 8, 2016

I'm so glad that i posted my intentions on converting to some sort of quick attach. I really hadn't thought about the possibility of a beefier crossbar since I just assumed that the bucket (or whatever other implement) would do the bulk of keeping the loader arms in line. However, your ability to use the bare loader with only the quick attach has much merit and of course the crossbar would then have to handle the stress alone. If it doesn't add an inordinate amount of weight, I think that it would be well worth it.

I'm also trying to figure out a good (i.e. "light") way to build the carriage for the forks. I'd love to see how you did your's and also hear of any changes that you would incorporate now that you've used it over some time. Any chance that you could be talked into taking and posting a picture or two?

CanDo · Sep 8, 2016

Yep, good idea zmansmac, there is excellent info on weight provided by various steel suppliers online. So, after looking up some details and doing a little calculation, here are my thoughts:

The John Deere system seems to do much of what I need but consistent bending of the hooks may be a bit of a problem and since I have access to a bunch of random pieces of flat stock I'm working up designing 45 degree lipped pockets to be on the upper end of the bucket (like Skid Steer) with a pin at the lower end much like the JD system. This should keep the bucket at close to the same distance from the loader arm pins. The only additional weight would be the pockets, 1" bucket pins and of course the crossbar between the quick attach on the loader arms. This would total maybe just over 10 lbs. if I go with a 1 square tube (.250) crossbar or about 35 lbs. if I go with a 2x3 crossbar. With no real additional outset of the bucket, a 25 lb. (+ weight of hooks etc.) loss of capacity may be worth the flexibility that I would get in using only the bare loader (with QA) without an implement attached. I'm aware that I would have to be careful of applying too much twisting force but if the load were kept in the center of the crossbar... Hmmmm...

zmansmac · Sep 10, 2016

CanDo, check your forum inbox. I sent you a private message.

CanDo · Sep 10, 2016

OK, been working away at the chosen concept for a quick-attach. Here are some pictures of the progress with a few words to help describe what I'm doing... er... trying to do.

I first played with a number of designs with pencil and paper and then spent a couple of days learning to use SketchUp in order to get a better idea of how it might work.

I then dug through the steel pile and pulled out a few pieces of flat stock and 3/4 ID pipe that might work and cut and drilled and welded and came up with the individual ears that will be welded up to be attached to the loader. Here's one of them although it's direction is flipped from the drawing.

Here's a matching pair with a set of wooden blocks used as spacers which are sized to allow the fit of the loader arms and hydraulics.

I then took some 1" round bar stock and turned and drilled out a few pins that will be welded to a plate which will then all be welded on the bucket. To try to create some consistency, I turned down a 7/8" diameter 1/8" deep step that will allow the pin to be located in a 7/8" hole drilled in the plate. Here's a pin:

And here is a pin alongside a plate and then the pin in the plate. You may note that I used 3/8" x 3" cold rolled bar stock for the plate so it should be strong enough. The third picture in this group shows the bottom plate (yet to be attached) to the ears as it would fit over the pin.

Next it was time to cut up various bits of bar stock to finish up the ears and create the pockets. I used 1/4" stock for the ears and the upper or outer part of the pockets but used 3/8" stock for the base of the ears and also the bases to hold the pins and pockets. Then I mocked up all the pieces in order to check fitment.

Looked OK so...

CanDo · Sep 10, 2016

OK, back to posting the rest of the pictures... Had to stop to eat dinner. Hmmmm BBQ Wings - not much better. It's like eating Sunday dinner on Saturday!!! That comment should age me. :laughing:

Anyway, here are some pics of the welded up pieces. This first is the completed ear assembly that will be attached to the individual loader arms. I've not yet done the cross bar that will lock the two together as I can't find a piece of 2 x 3 stock. I'm trying to build this without buying any steel although I may try the salvage yard. I like to think that I'm not really cheap, just Dutch. And yes, I am proud of my Dutch heritage.

This next is a pic of the pin welded into the base plate. You can see that the pin sits cleanly on the plate with the back side solidly welded within the drilled hole. Because of the recess in the 3/8" thick backing plate, very little grinding was needed to smooth out the back side of the plate. This plate then will be welded onto the bucket.

Below is a shot of the welded up pocket that will be welded onto the bucket in order to catch and contain the nose of the quick attach assembly which will be on the loader arms. You can see that one side is angled out in order to facilitate lining up the loader arms as it moves into the bucket. I've not yet done any additional welding on the inside of the pocket as I want clean contact between the sides of the mating assemblies.