mehan
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Block the blades and use a 1/2"
x 12" breaker bar to loosen up. Do not overtighten and use antifoulent when reinstalling.
Blade bolts to tight
- Thread starter Ron3
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x 12" breaker bar to loosen up. Do not overtighten and use antifoulent when reinstalling.
they're "supposed to" self-tighten.
When you turn the blades OFF, there is the pto clutch, which has a brake built into it. It's job is to stop the blades within 5 seconds of turning the blades off.
Therein lies an issue. If you put them in loose, turn the blades on and then back off, the inertia of the spinning blades then tries to loosen the bolts, and sometimes does.
If you torque 'em like they're supposed to be, with good quality bolts, they won't come back out until they need to be removed again.
On bad boy, they use chinese cheap fasteners that often seize into the chincanese spindle shafts. It just happens. And since they are 5/8'11, they're in there tighter than dick's hatband anyway, then they tend to seize up, and short of a 4' cheater on a 4' breakover, the only other way to remove them is heat. heat the bolt head nice and hot and then back it on out. Done tons of them like that. Bad boy uses very cheap designs on a lot of things, it works, but it's not ideal. It saves them (and ultimately you) some money.
When you turn the blades OFF, there is the pto clutch, which has a brake built into it. It's job is to stop the blades within 5 seconds of turning the blades off.
Therein lies an issue. If you put them in loose, turn the blades on and then back off, the inertia of the spinning blades then tries to loosen the bolts, and sometimes does.
If you torque 'em like they're supposed to be, with good quality bolts, they won't come back out until they need to be removed again.
On bad boy, they use chinese cheap fasteners that often seize into the chincanese spindle shafts. It just happens. And since they are 5/8'11, they're in there tighter than dick's hatband anyway, then they tend to seize up, and short of a 4' cheater on a 4' breakover, the only other way to remove them is heat. heat the bolt head nice and hot and then back it on out. Done tons of them like that. Bad boy uses very cheap designs on a lot of things, it works, but it's not ideal. It saves them (and ultimately you) some money.
Ron3
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With all due respect, they use 5/8x18 grade 8 fine thread blade bolts, . I just needed a bigger compressor mine was really small problem solved. Again with all due respect you seem to have a very negative attitude toward bad boy. Just my 2cents
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Yes and no. What most people don't realize is that air tool ratings like 90 psig are dynamic at the inlet of the tool, meaning it is measured while the tool is running free speed, so reduced volume of expanding air means lower pressure. Most set ups with a couple of 1/4" quick disconnects and 25 foot of 3/8" hose will struggle to achieve 90 psig dynamic at the tool with 130 psig at the compressor.
I realize this is my first post but I have a Bad Boy ZT Elite and was researching new blades and stumbled on this thread which interested me due to my background. The first 27 years of my career was at Ingersoll Rand where I lead the development of the majority of their air impacts currently on the market and the last 6 years I have been at a private company that supplies air and cordless tools to some of the major mobile tool companies. Just wanted to explain why I would chime in on the subject and say that if anyone has any questions on air tools or cordless tools, let me know and I will try to help.
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I know one thing that 5/8-18 on a Gravely can be a real pain to get lossen. I wasn't break them free with my 1300 ft-lb AirCat impact nor with a 5 ft pull bar with both feet on the mower. I just sent the customer someone with a 3/4 and 1 inch impacts to see if he can loosen them. After you get above 150 ft-lbs things to fuse to each other.
bertsmobile1
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Lugbolt
With due respect Lugbolt, yes what you said is correct about self loosening .
However that would only be the case for a blade that has just been installed and not used to cut grass .
Once the blade starts to work it will self tighten due to the drag applied to the blades by the grass being cut .
Again if you used to mower properly and only cut the recommended 1/3 grass length regularly then perhaps the self tightening effect would be less .
The only blades that I have ever seen come loose in use are the star holed ones that were not installed correctly ,
As for cheap Chinese fasteners I would be amazed if any mower maker did not use imported fasteners .
The market is just so tight & people are just so cheap .
Star,
Yes any 2 pieces of the same metal that come into intimate contact with each other will bond on a molecular level thus is the nature of the metallic bond .
So if you put a perfectly clean bolt into a perfectly clean shaft it would bond just as strong as a weld effectivly making the shaft & bolt one single item.
This is why the threads are plated or phosphated .
The USA found this out during the early days of the space race when they used relays only to find that in outer space the oxide coating on the surface of the contacts evaporated and the tiny voltages passing across the contacts was more than enough to weld them closed .
The nature of threads is such that when done up the two surfaces can scrape against each other to provide an active surface that will bond .
With due respect Lugbolt, yes what you said is correct about self loosening .
However that would only be the case for a blade that has just been installed and not used to cut grass .
Once the blade starts to work it will self tighten due to the drag applied to the blades by the grass being cut .
Again if you used to mower properly and only cut the recommended 1/3 grass length regularly then perhaps the self tightening effect would be less .
The only blades that I have ever seen come loose in use are the star holed ones that were not installed correctly ,
As for cheap Chinese fasteners I would be amazed if any mower maker did not use imported fasteners .
The market is just so tight & people are just so cheap .
Star,
Yes any 2 pieces of the same metal that come into intimate contact with each other will bond on a molecular level thus is the nature of the metallic bond .
So if you put a perfectly clean bolt into a perfectly clean shaft it would bond just as strong as a weld effectivly making the shaft & bolt one single item.
This is why the threads are plated or phosphated .
The USA found this out during the early days of the space race when they used relays only to find that in outer space the oxide coating on the surface of the contacts evaporated and the tiny voltages passing across the contacts was more than enough to weld them closed .
The nature of threads is such that when done up the two surfaces can scrape against each other to provide an active surface that will bond .
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That is basically what I figured out here on my own and it explains why so many people destroy cross point screws. They need to be shocked as I call it to break this bond. before attempting to loosen them. Even many stubborn screws can loosen using a initial smack.
I recently was told per service manual I could use a hub puller to remove the hubs that were tapers tighten to 300 ft-lbs. Well you can't as they are bonded after a while. It cost 200 usd to find out the manual was wrong.
I recently was told per service manual I could use a hub puller to remove the hubs that were tapers tighten to 300 ft-lbs. Well you can't as they are bonded after a while. It cost 200 usd to find out the manual was wrong.
Hammermechanicman
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I am amazed how much trouble people have with blade bolts. I remove and sharpen or replace a couple hundred blades a year. I zip them off with 6 point impact sockets and put some grease on the threads before i zip them back on with an impact. I don't use a torque wrench (it aint the space shuttle). Never snapped or stripped a bolt. Never had a blade come loose. Only ones i really have trouble with are the ones where someone hits something and F'd it up. Like the one with the star and they hit a pipe and sheared and smeared the star on the spindle. So tight the impact sheared the head off the bolt. Going to get a new spindle anyway. Haven't had a blade bolt yet my impact wouldn't take off.
Hammermechanicman
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I have a well (ab)used IR 2135TI running 140psi with 3/8" lines and hi-flow couplers. Gets the job done.
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My impact is an AirCat 1150K which has 900 ft-lb maximum torque and 1,295 ft-lb of loosening torque and I am using V style hi flow couplers and plugs. Now it is a lot quieter than the 109dB Ir 2135TI since iit has a tuned exhaust (86 dBA). Now it does consume more air at 8 cfm vs the 5 cfm if IR.
Now of course I am only running 125 psi vs your 140 psi. I also using a 125 ft 3/8" hose.
Now of course I am only running 125 psi vs your 140 psi. I also using a 125 ft 3/8" hose.