Torquing blade bolts question

[GarPA]

Most guys I know around here dont use a torque wrench to put their blades back on. My manufacturer and dealer also tell me I really dont need to use a torque wrench. Just make sure they are on tight but not so tight the bolt gets 'stretched'. Am I asking for trouble not using a torque wrench? thanks much

[TJLC]

I use an impact to remove and install blade bolts. Have not found an easier way to do it. I would try to follow the manual as close as possible as far as torque goes. My w/b is about 75-80 ft. lbs. and my z isabout 115-120 ft. lbs. Good luck.

[keifer]

I dont use one and have allways done fine but if i owned one i would use it.

[GarPA]

Keifer...yes that where I'm at....spend 10k for a mower but I'm too lazy/cheap to go up to Sears and buy a torque wrench....but if I really dont need it then why waste my time and money right?
Mr Manufacture rep even said I dont need one....just get them "very snug"...well that means I'll probably overtighten them

[Runner]

Because of the rotational direction (how's THAT for a "technical" sounding term!:D ) or, is that directional rotation...:rolleyes: Anyway, the blade bolts have a tendency to tighten themselves up even more just a bit when the blades are kicked on.

[AltaLawnCare]

I always use an impact to remove the bolts, and I've got a Snap On :cool: torque wrench.

I torque them to 85ftlbs on the Toro 52" WB.

[wxmn6]

Geez..... Snap On tools..... if I could afford them! Maybe in future but not now!

I have been considering about getting torque wrench because I have no idea how many ft/lbs of torque I tighten the bolts. I just simple tighten the bolts until I could not go any furthur. When it is time to change the blades it is always difficult for me to loosen the bolts, probably because I overtighten the bolts. I don't want to tighten the bolt with less torque than I usually do because I don't want to take the risk of blade falling off if it is not tight enough.

Although there are only a few reply in this thread, I would like to ask to see how many of you guys uses them.

[Ray&Christine]

A couple of days after a bought my new Walker Mower I had a knock at my front door, it was the UPS guy and he gave me a package. It was a torque wrench sent to me from Walker. I guess it must be important to torque the blades otherwise they wouldn't have spent the money out of thier pocket to send me a torque wrench.

Ray

[bkd]

I always use a torque wrench. This way you know for sure you are not putting them on too tight or too loose.

[Richard Martin]

I use a Sears torque wrench. Dixie Choppers have a special fiber washer that can get crushed and distorted if overtightened.

[Albemarle Lawn]

Why? If you mount the blades too loose, are they harder to remove?

Answer: Because if the blade is not bolted on tight enough and it hits something, it stops instantly, jerking that bolt on soooper tight and possibly shearing it off. Any Gravely 260Z users, esp 72" deck are sure to be familiar with this scenario.

Make em tight or a rock will come along and tighten them for you when you least expect it.

If no spec is available, find an engineering chart that will give you a torque spec based on lenth, diameter, and grade of bolt based on the material (steel) it is threaded into.

Most 3/4" hex = about 80 lb/ft
Most 7/8" hex = about 100 lb/ft
Most 1" hex = about 115 lb/ft

All of above assuming grade 8 blade bolt.


Ken

[awm]

ive heard of blades getting slung out from under a mower . but any time mine have ever came loose the spindle lost grip on the blades and the only thing that happened was the blade didnt turn.
i guess its possible for the blade to bounce back up into the other blades if it came off,
but never had it happen.
in any case i use an impact ,but dont try to get so tight ,its hard to get off..

[HLC]

Just my 2 cents here on Snap-On Torque wrenches. I only do the lawncare biz on the side. I am one of those guys that someone was talking about (bashing) a few months ago (I believe it was Stone) who works for the gov't full time. Anyway, we use torque wrenches a lot and went exculsively with Snap-On for a while. Big mistake. I know Snap-On makes good tools but their Torque Wrenches SUCK. Don't waste your money. I can't offer a good substitute because the best ones we've found are through gov't sources. Again...........just my 2 cents worth.

[Double D]

electric impact wrench is the way to go, plug it in and zap those blades off. Also, have a 12v impact wrench that I keep on the trailer for getting blades off on the road.

[wxmn6]

Not sure about the electric impact wrench. A few days ago I went to WalMart to pick up a set of ramps. I saw boxes of 12v impact wrenches on the shelf and it said that it can torque up to 250 ft/lbs. Sells for around $35 but I think that impact wrench have too much of torque for tightening mower blade bolts.

[wxmn6]

Impact wrench may be fine for taking blades off but not for putting blades back on.

I am looking at Husky and SK torque wrench. Not cheap still but affordable. Anyone have good luck with them?

Oh I forgot one thing.... do you use 3/8" or 1/2" torque wrench? Thanks.

[Richard Martin]

1/2". Trying to put 100# of torque on with a 3/8 can be rough.

[wxmn6]

I agree with you. Even though that my John Deere GX325 mower blade bolts only needed to be torqued to 50 ft/lbs, I'd still get the 1/2". Never know if I will need to use it for something else that need more torque.