Rolling resistance

[john maddock]

My principal question to the BFF Brains Trust is this: will my MF4225 pull a 7t. sheep's foot (padfoot) roller?

The tractor's Nebraska Test says it will pull 3.6t. How does that figure relate to pulling said roller, which will be 1500mm in diameter and could be up to 2.0m wide, on a (nominally) 150 - 200mm thick layer of clay?

JV

[Ironhead]

My principal question to the BFF Brains Trust is this: will my MF4225 pull a 7t. sheep's foot (padfoot) roller?

The tractor's Nebraska Test says it will pull 3.6t. How does that figure relate to pulling said roller, which will be 1500mm in diameter and could be up to 2.0m wide, on a (nominally) 150 - 200mm thick layer of clay?

JV

This opens a whole bunch of questions

• was the test performed as a straight "drag" or with something that is rollable?
• is the roller attached with bearings or is it a simple steel2steel set-up (steel shaft inside a pipe)?
  
  • if it is steel2steel, what diameter is the pipe (bigger is better)?
  • if it is steel2steel, is there any way to add some grease fittings to lube the
  
  
• is the roller solidly filled or does it fill with a fluid, like water?

[john maddock]

This opens a whole bunch of questions

• was the test performed as a straight "drag" or with something that is rollable?
• is the roller attached with bearings or is it a simple steel2steel set-up (steel shaft inside a pipe)?
  
  • if it is steel2steel, what diameter is the pipe (bigger is better)?
  • if it is steel2steel, is there any way to add some grease fittings to lube the
  
  
• is the roller solidly filled or does it fill with a fluid, like water?

Good questions Ironhead.

I don't know how the Nebraska test was conducted coz that info came from here:

http://www.tractordata.com/farm-trac...225-tests.html

No info that I can see if the tractor test reported on was 2WD or FWA. (And I remembered the pull inaccurately).

The OECD test is here:

https://tractortestlab.unl.edu/Masse...son%204225.pdf

and the FWA tractor in this test pulled only 4k pounds!

As to the roller, I haven't built it yet. Propose to weld a set of padfoot shells together, use standard pillow block bearings on the shaft, use thick walled RHS for the frame with a weight tray - and fill the shells with concrete. Width as yet undetermined.

I'm guessing that wheel spin will be the limiting factor, coz the tractor I have is only 2WD, but the test figures seem low when I consider how it handles the round baler, which would weigh around 1.5t., I think.

That's why I used the subject line of "Rolling resistance", coz it seems to me that that is the big variable.

JV'

[Paw]

I think those drawbar pull tests are done with a very heavy test rig connected via a strain gauge. Apply the brakes on the rig till the tractor can't pull it and read the max value on the gauge.

[Exfarmer]

My principal question to the BFF Brains Trust is this: will my MF4225 pull a 7t. sheep's foot (padfoot) roller?

The tractor's Nebraska Test says it will pull 3.6t. How does that figure relate to pulling said roller, which will be 1500mm in diameter and could be up to 2.0m wide, on a (nominally) 150 - 200mm thick layer of clay?

JV

far more importantly, Can it stop said roller going downhill?

[john maddock]

far more importantly, Can it stop said roller going downhill?

Ha! Well spotted Ex! I hadn't thought about that, but it's obviously a potential trap. Since the roller will be used to consolidate soil on a new dam, it will be used on the level. However, during transport it will need to be moved down a slope, and 7 or so tonnes could potentially push the tractor out of control. The more I think about it, the more relevant your question becomes. Thankyou for alerting me to the risk.

JV

[Exfarmer]

Ha! Well spotted Ex! I hadn't thought about that, but it's obviously a potential trap. Since the roller will be used to consolidate soil on a new dam, it will be used on the level. However, during transport it will need to be moved down a slope, and 7 or so tonnes could potentially push the tractor out of control. The more I think about it, the more relevant your question becomes. Thankyou for alerting me to the risk.

JV

I would hate to pick up my newspaper see headline "farmer rampages through Hobart with tractor" . police arrest well known local man John Maddock, who was heard screaming, " my brakes, my brakes, my kingdom for some brakes?"

[john maddock]

I would hate to pick up my newspaper see headline "farmer rampages through Hobart with tractor" . police arrest well known local man John Maddock, who was heard screaming, " my brakes, my brakes, my kingdom for some brakes?"

Blood oath, Ex! Me too!

On tother hand, should a certain politician (or more, for that matter) be standing on a street corner, I'd be very happy to take advantage & change some fat cats into some flat cats! (We have a *very* unneccessary election in a few weeks).

JV

[Exfarmer]

Blood oath, Ex! Me too!

On tother hand, should a certain politician (or more, for that matter) be standing on a street corner, I'd be very happy to take advantage & change some fat cats into some flat cats! (We have a *very* unneccessary election in a few weeks).

JV

wouldn't we all! We have our fair share. Don't know if the story of our Ex PM David Cameron has hit your shores yet, but it seems he teamed up with an Australian guy to promote his business Greensill which was some type of factoring operation. DC was hoping to take a cut of £60m out of it , thankfully the business went bust and he has not got a penny. Sorry for the 50,000 who lost their jobs through it though

[john maddock]

wouldn't we all! We have our fair share. Don't know if the story of our Ex PM David Cameron has hit your shores yet, but it seems he teamed up with an Australian guy to promote his business Greensill which was some type of factoring operation. DC was hoping to take a cut of £60m out of it , thankfully the business went bust and he has not got a penny. Sorry for the 50,000 who lost their jobs through it though

Greensill & Cameron are certainly known here - but not universally. Only those reading the specialist news feeds would be aware.

I presume the Aus connection is Julie Bishop, our Foreign Minister in the previous il-Liberal government. So far, she is keeping quiet about what she knew and when.
Crikey had this story recently:

https://www.crikey.com.au/2021/04/08...ill-questions/

I have no idea if I can see it because I'm a subscriber, but hopefully it won't be behind a paywall for you.

It says she was a registered lobbyist for Greensill until she tore up her contract in March, and she was an "advisor to the Board", alongside Cameron.

Says she arranged a meeting between Greensill & our ex Finance Minister (now the head of the OECD?) in Davos. Crikey finishes by asking 10 questions it would like answered.

JV