How much ballast is typically needed for a MX5800?

[4570Man]

Yea, I recall someone doing it once already, and IIRC it was on a larger 60-70hp tractor? Not sure why we need a proof of concept though. Basic levers and physics. Provided you have at least enough weight to keep the rear axle down.....the rear axle IS the fulcrum. Measure the COG of the weight behind the rear axle centerline.....and measure the front axle to rear (wheelbase.) If you have a wheelbase of 70", and a load center for your weight box that hangs 35" back....simple 2:1. For every 2 pounds added to the ballast box (BEYOND what keeps the rears on the ground) is 1# unloaded from the front axle when lifting max weight.

Wouldn't it be the distance from the rear axle to the balance point on the load?

 

[LD1]

Front loader load? No. Not unless the load is touching the ground.

We aren't talking about how much the FEL load adds to the front axle. THAT would need the balance point of the load to the front axle measurements.

For figuring reduced weight on the front axle....Where the FEL load is at is irrelevant

 

[4570Man]

Here's another small scale experiment. I divided my 'tractor' into 3 equal parts. Although the proportions aren't representative of a real tractor it makes for easy physics. The wheel base is 8.3 inches and the end of both ends of the board is 8.3 inches from the closer axel. I weighed 3 boxes of shotgun shells and surprisingly they were exactly the same at 34.9 oz each. The weight of the front axel is 44.5 oz with a box on each end. The axel weight is 15.5 with 2 boxes on the back.

 

[LD1]

So adding a box at 35 oz on the back, unloaded the front by almost the same amount. Minus a little differences in measuring.

My point proven

 

[rbtjr]

From the OP, thanks to all for your feedback. I have decided that I am going to get a ballast box that will give me the flexibility to add 1200-1800# on the back. The box itself will weigh 1500# when full of dry sand. I can vary that with less sand or almost full with sand and add iron weights I have, or fill the box partly with concrete, etc. Anyway, I appreciate all of the input. I will follow up with a report on how it goes.

 

[rbtjr]

This is a follow-up report from the OP. I bought a OEM Kubota ballast box that weighs 220 # and holds something like 1,250 # of dry sand. I put something like 1,000 # of sand in the box, put four 4" PVS vertical pipes in the four corners of the box to hold chains, tools, my chain saw, etc. I bought a trailer-hitch receiver, had a chain hook and clevis welded onto it, and had the receiver welded onto the back of the box. I had the box strengthened by welding a 1/2" by 4" steel plate inside the box at the same level as the OEM steel plate that strengthens the area where the 3PH pins are. I didn't fill the box entirely with sand so I can add some weights on the top (I have 5 35 # suitcase weights that I could put on top of the sand if I wanted to). So, I ended up with a box that weighs a little over 1,200# and I can increase it to about 1,375 # if I want to. I just finished all of this but the box feels about right. Here are a couple of pics of the finished product:

 

[sdef]

Looks great. Mine weighs 1235# measured with concrete fill and works well for my Kioti DK45 tractor. I can also add a bit more weight if required. I use mine only for weight as I have lots of storage on the tractor.