Sharpened blades on mower deck

   / Sharpened blades on mower deck #21  
Rented a torque wrench to do a big diesel overhaul It was 4 feet long took two men to torque things to 450 and then 650 lb .
 
   / Sharpened blades on mower deck #22  
just look at the free-body diagram for a blade on a spindle. Blade bolts are self tightening. Hit something and they really get snug.
 
   / Sharpened blades on mower deck #23  
I've read elsewhere in OTT that the WSM for Kubota decks seem to recommend 450lbs/ft for most of the MMM decks. My 1/2" Dewalt pneumatic impact will do 650ft/lbs. I haven't found a 3/8" that will go above 350. If possible, I think I'll be blocking my blades with 2x4 and leaving mine on to sharpen. Just seems nearly impossible to get the torque right otherwise.

JK22,

PLEASE recheck those torque specs ! ! ! My SM for the 54" MMM has a spec of 72.3 to 86.8 ft lbs. I tighten mine to 75 ft lbs. Have had no problems with it in nearly 500 hrs of use.

Dave
 
   / Sharpened blades on mower deck #24  
JK22,

PLEASE recheck those torque specs ! ! ! My SM for the 54" MMM has a spec of 72.3 to 86.8 ft lbs. I tighten mine to 75 ft lbs. Have had no problems with it in nearly 500 hrs of use.

Dave

Please note I previously stated my prior post was incorrect. I can't edit my post--- but I did do a new post above. I regurgitated bad information.
 
   / Sharpened blades on mower deck #25  
Anyone with the initials J/K can't be all bad.... we forgive you your transgressions .... :)
 
   / Sharpened blades on mower deck #27  
I purchased a Harbor Freight fancy 1000lb/ft impact to try and get my blades off my finish mower. I will certainly be putting some anti seize on the bolts when putting back on.. and torquing to proper value with hand torque wrench.

I remember as a kid we had a gear reducing truck lug tool. It had a 5' handle and a big head with gears. It was easy to move the lever, but was slow going.
 
   / Sharpened blades on mower deck #28  
I purchased a Harbor Freight fancy 1000lb/ft impact to try and get my blades off my finish mower. I will certainly be putting some anti seize on the bolts when putting back on.. and torquing to proper value with hand torque wrench.

I remember as a kid we had a gear reducing truck lug tool. It had a 5' handle and a big head with gears. It was easy to move the lever, but was slow going.

First time I've seen the words "fancy" and "harbor freight" in the same sentence.
 
   / Sharpened blades on mower deck #29  
[ TL;DR - if you wet threads before torquing, don't torque as hard ]

Just a quick FYI, if you oil/grease/anti-seize threads before torquing:

With less friction (wet threads), the bolt will stretch more before a
torque wench will click. Because friction is such a big factor in bolt torque, it is important to know the
difference between applying torque to a dry bolt and a wet bolt. Using oil, anti-seize or other types of
thread lubricant is a common practice, but an understanding that wet threads require less torque than dry
threads because of friction is very important.​

(From this link, which was the first thing that popped up from a google search for "wet torque vs dry torque".)
 
   / Sharpened blades on mower deck #30  
I'm a firm believer in a torque wrench. I torque mine to 80 ft/lb
 
 
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