Blade bolts to tight

SeniorCitizen said:
You people are causing yourselves a wagon full of un-necessary problems with those impacts . Oil the threads , tighten the nuts with a box wrench about 12" long until they feel tight and go mow . Those manufacturers are specifying those ridiculous torque values because of liability .
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Apparently you never had blades to come off or strip star mounts. I tighten all these screws and nuts to factory spec'd torque using a torque wrench and not the impact as 950 ft-lb will snap off most screws. Impacts are for removing these and not for installation.
 
It is all about proper maintenance or lack there of
When you get a customer who never removes a blade to sharpen it so spends 200 hours smashing his way through tough tufted grasses with very blunt blades and only brings in the mower when the missed strip between the blades is more than a foot or their is so little of the flute left that the deck clogs every 10 minutes then those blades will be really tight .
It has nothing to do with oiling the threads or proper tightness when replaced it is all about the spindle trying to turn the blade but the blade not turning at the same speed tightening the bolt / nut.
FWIW I have a 1" rattle gun that is good for 2500 ft lbs that I run off a Boomwade jackhammer compressor and there are some that even this will not shift till eventually it rips the head off the bolt
After that I can slip the blade off & undo the remainder of the bolt with my fingers.
The threads are not too tight, it is the head compressing the cup washers and clamping down too tight on the blade
Usually I keep a stock of blade bolts & cut off the heads that my 1/2 rattle won't shift because that is quicker than driving up to the machinery shed, firing up the 6 cylinder diesel engine, filling the 75 gallon tanks and hooking up the 1" gun ( ex coal mine ) in the hope that the head does not twist off because I don't have replacement bolt .
 
165 psi is way beyond the design spec of my Air Cat as it is designed for 90 psi supply.

Hopeful the air tank is designed for this much pressure and the tank is drained every so often to keep it from rusting out.
 
The compressor is a Quincy american made industrial 60 gal. Rated for 175psi. I installed an automatic drain so every time it starts it drains for ten seconds. The IR 2235 handles the pressure ok. I use 3/8 li e and high flow connectors. The air hammer is another story. Have to dial the pressure back or it is too violent to control
 
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I kinda been looking at upgrading to 30 yrs + Manga 25 gal setup but finding room for a 60 gal might be problematic as the 24x24 shop is already so full that have work outside now.

I got an air hammer but have only used it once since 2014. Now die grinder get used every day and I need to upgrade it to one that uses less cfm but still has the same power. My main goal for this year is more vertical storage boxes for belts, pulleys, wire, and spindles that way I can keep the mice out of the belts and the wire.
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StarTech said:
It does take a good impact to remove these blades. Even a good impact will have problem if there is resistance in the air supply line causing line pressure drop.

A good example of this was here. My AirCat 1150 couldn't even loosen my lug nuts on my pickup that were tighten to only 70 ft/lbs. Now of course I using a 100 ft 3/8 air line. My problem was the under size M style couplers and plugs. Even the properly size M couplers and plugs it still struggled. This is when check the supply pressure with the impact free running. The line pressure was dropping to 20 psi from the 125 psi standing pressure. I switch out all the couplers and plugs to V style (high flow) and I haven't had any problems since except for one Scag mower which has always cause problems removing the blade bolts.

The 1/2" Campbell Hausfeld impact that I had and gave was useless for removing many fasteners.
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Air pressure makes all the difference. And if you have a variable force impact make sure it's set on high. Also:
Some thoughts on penetrants for disassembly.
And when you reassemble, a dab of NeverSeize on the threads works wonders for the next disassembly. Some may say its dangerous but the majority of the clamping friction force is in the bolt head face and blade contact area....that and there is a lock washer involved, too.
 
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