Acres cut per hour

[Farmwithjunk]

Sharpening blades: I assume you know this already BUT I found out the hard way last year. On an MX6 (presumably on the MX8 ?) the bolt torque for getting the stump jumper on/off is 450 ft -lbs. That means a big socket set and a cheater pipe about 5 feet long if you are strong as ****. You need help. Worse yet, the torque specs on the flails are either 600 or 650 ft-lbs. If the stump jumper is not torqued to spec you will eventually find it sailing out through the field as it did on me. The manual says tighten it near spec values, then belt it with a sledge hammer and do it all over again, twice -- I'm serious.

As a practical matter, you really need a big torque multiplier wrench and stuff most people do not have lying around to get those blades on and off. It's almost better for us po-folk to jack the thing up on something safe and sharpen the blades on it (using a carbide disk on a drill) without removing them.

No need to remove the stump jumper....or the blades either for that matter. A waste of time if you ask me.... It's FAR easier, faster, and with that, better to simply grind them in place without removing anything. Use a 4" angle grinder.

When we do need to remove/re-install blades, I use a 1" air impact wrench.

 

[LD1]

No need to remove the stump jumper....or the blades either for that matter. A waste of time if you ask me.... It's FAR easier, faster, and with that, better to simply grind them in place without removing anything. Use a 4" angle grinder.

When we do need to remove/re-install blades, I use a 1" air impact wrench.

Personally, I like removing the blades anytime I sharpen them. I have two bushhogs, a 105 and a 306. Theres a little access door in the deck. So far, my IR 2135Ti 1/2" impact is all that has ever been needed to remove and replace them.

But the reason I loke taking them appart is because when the time comes that I NEED to take them off, they wont be siezed on causing me to fight with it for hours.:thumbsup:

 

[JWR]

No need to remove the stump jumper....or the blades either for that matter. A waste of time if you ask me.... It's FAR easier, faster, and with that, better to simply grind them in place without removing anything. Use a 4" angle grinder.

When we do need to remove/re-install blades, I use a 1" air impact wrench.

I sure do agree if you have that big an air wrench. Getting the right torque on one may be hard to do (somewhere between not enough and twisting the thing off.) Maybe there are torque gauges for impact wrenches ??

 

[TripleR]

I sure do agree if you have that big an air wrench. Getting the right torque on one may be hard to do (somewhere between not enough and twisting the thing off.) Maybe there are torque gauges for impact wrenches ??

They make torque sticks, but I don't know much about them.

 

[Farmwithjunk]

Personally, I like removing the blades anytime I sharpen them. I have two bushhogs, a 105 and a 306.

5 bat wings, 4 single spindle 3-point decks, all needing a touch up every 10 work days...(plus another 6'er @ home) The time involved, remove v in place, doing them in place wins by default. We expect to put on around 750hrs per mower this summer.

Blades come off once during the season, about 2/3rds the way through, and again during winter maintenance, for a closer inspection. (That caught a cracked blade before it broke last summer!)

 

[Farmwithjunk]

I sure do agree if you have that big an air wrench. Getting the right torque on one may be hard to do (somewhere between not enough and twisting the thing off.) Maybe there are torque gauges for impact wrenches ??

In a quick search, I couldn't find the specs on my 1" impact, nor the 3/4", but we just bought one of these... Ingersoll rand impact wrench:Ingersoll-Rand 2130 1/2-Inch Heavy-Duty Air Impact Wrench | Ingersoll Rand Impact Wrench
With 1/2" near the capacity to handle what we're looking at with a bush hog blade bolt (try saying that 3 times real fast...) the 3/4" will handle the job, and the 1" will break loose anything I've ever asked of it. I guess not everyone has a full shop, a service truck, and 2 service techs working for them though......

All these guns have the ability to be dialed back to avoid over torquing. Not accurate enough to be torquing head bolts, but plenty close enough for a bush hog blade.

 

[LD1]

Yea, with that much maintenance I probabally wouldnt remove them either. But I dont do much bushhogging. I only sharpen maybe 3 times per year.

This IR2135QTI 1/2" Air Impact Wrench is the impact I use. For the money, it cant be beat IMO. It has NEVER let me down. And it is as light as my little 3/8" impact too:thumbsup:

 

[Builder]

Sharpening blades: I assume you know this already BUT I found out the hard way last year. On an MX6 (presumably on the MX8 ?) the bolt torque for getting the stump jumper on/off is 450 ft -lbs. That means a big socket set and a cheater pipe about 5 feet long if you are strong as ****. You need help. Worse yet, the torque specs on the flails are either 600 or 650 ft-lbs. If the stump jumper is not torqued to spec you will eventually find it sailing out through the field as it did on me. The manual says tighten it near spec values, then belt it with a sledge hammer and do it all over again, twice -- I'm serious.

As a practical matter, you really need a big torque multiplier wrench and stuff most people do not have lying around to get those blades on and off. It's almost better for us po-folk to jack the thing up on something safe and sharpen the blades on it (using a carbide disk on a drill) without removing them.

That's all I've ever done. I like the result better on a bench grinder, but I use my 4" dewalt angle grinder, lift the mower up about 16" and have at it. Seems to work OK. Would love to be able to R&R blades easily and bench grind them.

 

[JWR]

That's all I've ever done. I like the result better on a bench grinder, but I use my 4" dewalt angle grinder, lift the mower up about 16" and have at it. Seems to work OK. Would love to be able to R&R blades easily and bench grind them.

Yep. Agree. One guy mentioned using a large air wrench when the blades really do have to come off. That's surely the best route, especially if you don't have help. But I don't know how one sets torque values using an air wrench. Is there a gadget for doing that ?

 

[LD1]

Yep. Agree. One guy mentioned using a large air wrench when the blades really do have to come off. That's surely the best route, especially if you don't have help. But I don't know how one sets torque values using an air wrench. Is there a gadget for doing that ?

Yes they make gadgets, but they arent as good as an actual torque wrench.

Bt I use neither. About the only thing I break a torque wrench out on anymore is head bolts, rod and main cap bolts, and some automatic transmission stuff.

I just hammer on them with the impact til it quits. Then get the 3/4" drive socket and breaker bar with ~3' cheater pipe and see if I can tighten it anymore. Usually not and I call it good:thumbsup: