rotary mower guestion

hello all-working on gearbox of 7 ft. rotary mower, when I notice one of the blades is bent up on the end quite a bit. blades still have some life left, & would like to use them on some rough mowing before replacement. can this be straightened without damage to metal & how? both blades could be cut equal as second option, but lose quite a bit. thanks--

i'd replace the blades. if you try and straighten it, you could take the temper out and have the blade break. pretty scary to have a broken blade come flying out.

mite-help,remove the blade and use a hydraulic press to straighten it up cold.

(quoted from post at 13:46:26 02/13/15) hello all-working on gearbox of 7 ft. rotary mower, when I notice one of the blades is bent up on the end quite a bit. blades still have some life left, & would like to use them on some rough mowing before replacement. can this be straightened without damage to metal & how? both blades could be cut equal as second option, but lose quite a bit. thanks--

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see no reason not to straighten. Already been bent once. The shop that sharpens blades locally does not grind away metal, they use a drop hammer to form the metal into a new edge.

I suppose one could bend one of these blades, given the metallurgy, concern of embrittlement or similar, given the speed and mass of them rotating, why would you want to chance that. As is they are more than likely not cutting efficiently, I'd be inclined to leave them on if there was no out of balance problems, significant vibration when engaging the pto or while running it. The rough areas of to cut, whats rough about it, small trees, saplings, terrain with rocks etc. ? These tolerate quite a bit, most of them, but its advisable to skip areas like that or clear, clean up the area before cutting. Small trees and saplings can be reduced if you start with the deck up high, and work down until its too much, makes a lot of noise, lots of impact, shock loads, vibrations, I find its not worth it. Worst case is abusing one til something breaks, oil seals leak etc. Make sure the shear bolt is correct grade, (usually grade 2 on the pto shaft) or slip clutch is correctly operating, your blades might be attached with shear type shoulder bolts, my Rhino SE-6 is. More than you asked for, but I'd replace them to be safe, I have seen how far one of these can toss a loose rock, of cantaloupe size, up over a hedge row, a piece of metal coming out could easily be like a bullet or fragmentation shrapnel.

Here are some photos of bent, worn out blades and the new replacement blades. When I put these on, in the same conditions, 1st cut hay grasses etc. it cut so much more efficiently, and I could run in one gear higher, which says a lot for using good blades and having the mower correctly adjusted to the tractor.

Cutting the ends off the blades is a waste of time, its going to create an out of balance condition, unless you weigh them to be even, and its not going to cut very well at all.

If one was going into really heavy vegetation or similar, possibly a smaller mower, but heavy enough to do the job meaning the gearbox is rated for the power available and then some. A friend has a real heavy duty 5'-0" mower, deck and blades, on the same tractor but harsher conditions, I'd take the 5'-0" mower over my 6'-0" mower on the same tractor every time.

I'd get new blades, specially if you're doing work for someone else. Buddy of mine had a blade break, heard a BAMMM!!!! and looked up just in time to see the half of blade go whizziig past his ear, fly about a hundred yards off into the field, he drove over and got it. MIssed back of his head abour 5 inches.

That's got to be pretty rare for a blade to come close to the operator if he's in the seat, it would have to bounce off of something.

My blacksmith says it got bent cold, it can be straightened cold. Temper doesn"t change unless it is heated, and there is no need to.

Of course it can be straightened. Lay it on an anvil and hammer it straight. It bent once, it can bend again.