# Cutting edge bolts



## jojosaw (Jan 15, 2006)

I plow for a local Hiway dept. And cant seem to keep a cutting edge on my blade. Bolts either fall out or shear off. I am running an 8' fisher mm2 with an 8" cutting edge. I Have tried lock nuts, lock washers and both together but now the bolts just seem to shear the heads off. Today plowing roughly 2-3 inches my cutting edge fell off after 15 min with brand new bolts. Does anyone have any tips. Thanks


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## echovalley (Dec 5, 2004)

jojosaw said:


> I plow for a local Hiway dept. And cant seem to keep a cutting edge on my blade. Bolts either fall out or shear off. I am running an 8' fisher mm2 with an 8" cutting edge. I Have tried lock nuts, lock washers and both together but now the bolts just seem to shear the heads off. Today plowing roughly 2-3 inches my cutting edge fell off after 15 min with brand new bolts. Does anyone have any tips. Thanks


Is your trip edge perfectly straight or does it have a bow in it somewear?


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## Mick (May 19, 2001)

Are you using bolts supplied with the edges? The washers and nuts aren't going to help the strength (weakness) of the bolts, themselves.


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## lorentzlawnsnow (Aug 9, 2005)

sounds like you're using soft bolts


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## itsgottobegreen (Mar 31, 2004)

Go get some grade 8 bolts. Your 8" cutting edge is putting to much stress on the trip edge. So thats why they are breaking. Get a 6" cutting edge, you would be better off by doing so.


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## Rappa (Dec 2, 2003)

Not to mention todays storm was brutal on the plows. That layer of ice under there was trippin everyone up. I bet your not the only one today...


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## tessdad (Jan 25, 2005)

If you have a Cat dealer near you, you will find they have a very fair price on high quality bolts.
Before you bolt the edge back on, check the face of the trip edge and the back and front of the cutting edge for any high spots. It is very common to find high spots on a cutting edge where the square holes are punched. Take a small 4 1/2" grinder to the face of the trip edge and the cutting edge, do not cut into the metal, just flat disk the wheel to remove any high spots. When installing the hardware use a never-seize type grease on the threads, (it will allow you to get them tighter), after tightening the bolt as tight as you think you should, hit the heads of the bolts with a big hammer and tighten them again, you will notice a difference.


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## Joe D (Oct 2, 2005)

I went through the same thing on my Fisher with the 8" edge. You need to drill out the edge and mold board to acept 5/8 grade 8 bolts. If that didn't work i was going to step up to 3/4 in but I never broke another bolt after the 5/8 went in.


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## jojosaw (Jan 15, 2006)

I am using the supplied bolts, My trip edge does bow out in the middle somewhat
. I am going to try to drill out the holes to accept the 5/8 bolts, the 1/2 inch bolts seem to swim in the holes so I can see why the edge might be able to shear bolts. Thanks for all the sugg.


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## jojosaw (Jan 15, 2006)

I am using the supplied bolts, My trip edge does bow out in the middle somewhat
. I am going to try to drill out the holes to accept the 5/8 bolts, the 1/2 inch bolts seem to swim in the holes so I can see why the edge might be able to shear bolts. Thanks for all the sugg.


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## grandview (Oct 9, 2005)

Bump them up to grade 8 did it with Boss plow.


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