Finally getting around to putting new cutting edges on my Champion 740A.Of course Im on a low budget so thought Id try reusing the bolts. So far so good Ive got edges removed and about to install new ones. question is the washers are dished,the mould board has kind of a dished recess for the washer.Wonder what I should do:install dished as before ;turn over so its domed;pound them flat...? etc.
Cutting edge bolts are so cheap I would never bother to try to reuse the old ones. You are not being frugal when the cutting edge moves around and eats everything else up.
X2 Old iron hit the nail on the head. Those screws won't survive a proper torque. Once they lose their grip, they're gonna float around damaging the base and the edges both . Not trying to pile on, just trying to stop you from incurring a loss that we can see coming.
That kind of dished recess was caused by the nuts working and wearing the edge support, then adding washers becomes necessary as a corrective measure.
if your used standard nuts -15/16 socket for 5/8 bolt move up to the oversize nuts 1 1/16 socket see if you can eliminate the washers
It costs what it costs to do the job right. I've only reused cutting edge bolts on things like dozers when I turned the edges and that is only when the operator hasn't taken the wear too far and worn off the ends of the threads on the bolts. As stated above, this is a false economy. When I had the mold board worn in the way that you speak of I liked to spend the time and weld up the groove around the hole and grind it flat again. I have found carbon rods of the right size to put in the hole while I welded to maintain the hole diameter.
In dealing with older equipment it is sometimes necessary to do what you have to do to keep them running. We use hardened Cat washers under the nuts on frogs that have the wear from previously loose hardware. Another option is flanged nuts that have a flat washer built in. If forced to reuse what you have I would use the dish the way it is. If you turn it over the washer may distort worse and break. Happy grading !
If the dish is deep enough the hard washer will break up anyway leaving the loose both to wallow out the hole.
Good point John C. Keep a wrench handy and check them frequently? We use our graders for snow removal and find that retorqueing after a shift or two often turns up a few that have backed off or stretched.
Wow thanks for the great replies.when I looked closer the dish in the mould board was actually I think a machined recess that is slightly smaller than the washers hence the dishing.the washers are the same od as given in the specs on the black cat site.1.5 inches.so not sure what is supposed to be used maybe a nut with integral washer that's a bit smaller?they are 3/4 bolts. I think the recess is 1 3/8.i did use the old bolts mainly because that's all I had and I'm out in the sticks big-time. but haven't ruled out getting new ones will phone around tomorrow.meanwhile I'm only using it for chickencrap little jobs and run it myself,retorqued them twice already.
We reuse bolts on our graders until they can’t be used anymore. During the winter we change blades every week. Maybe more frequently, depending on the snow conditions. The main thing about the bolts is keeping them in the cairrage slot when you torque them down. We also use the large head bolts for our style blades we get in, and the large nuts. I’m sure some of the bolts have seen 15-20 blade changes easily. Some guys have hit manholes during the winter and bent the blades and the bolts still never failed. So to each their own. Use your best discretion.
When your time costs little or nothing I see no problem with taking the care when disassembling to try to reuse as much hardware as possible, just be pragmatic that you may not be able to reuse everything that you take off for various reasons. Hardware stretching and consequent bolt loosening is something you need to be aware of. Poor quality hardware can have a big impact on that, especially the washers. If they are too soft then it will be a struggle to keep the bolts tight. If you have a recess in the moldboard frog for the washers to fit into then they should be of an outside diameter that actually fits inside that recess. It might be stating the obvious but you'll struggle to keep the bolts tight if the washers dish when you tighten the bolts. I don't think anyone suggested to tighten the hardware starting from the centre of the cutting edge and working to the outside, then once you have it all tightened go back and do it a 2nd time in the same sequence.
Good point, never even thought to mention that. I kind of took it as common knowledge. Just like torquing a tire on. Pet peeve of mine is having long bolts. When they stick out of the nut for longer then 1/2”, they should get cut off. Just asking them to get bent and the threads messed up, making it a chore to remove them later. Not To mention the headache when I’m cutting the edges of my cut, and the bolts hit th existing asphalt or concrete. Not fun.
I hear you. It's one of those good practices that falls into the category of "I thought everyone knew that" ........... I don't like to see the bolts more than one complete thread past the nut. Let's face it the additional length isn't doing anything for the strength of the bolted joint.
The dishing you talk about comes from the nuts burying themselves into the moulboard upon tighting . On trim graders could see edges changed up to twice daily we found the back of the adaptor chewing out (cat dont fit washers from new ) So weld up the depression fit hard washers prob fixed .And yes Nige thats is always good pratice to tighten bolts from the centre out
For those who say you can’t reuse grader blade bolts. Here’s proof that you can.
What brand of blades are those ? Not used to seeing edges crack like that.
I've seen that happen when the bolts don't stay tight.
We, none of us said,"you can't. " we advised against. The money you save on hardware will haunt you with extra maintenance and wallowed out holes. I could stick my head up a cows ass, doesn't mean I should. You do you, I do me.
Next action is to get the mold board or frog clean, weld the dish sections up, re-drill the hole round then grind the weld flat for new nuts.
had all sorts of grief with operators grinding off the ends of the moldboard during snow removal against the curbs. I used old D8 track pins welded to the ends. the worst time was when one machine came back with the outer two holes ground off the frog. that was after he had worn through the d8 track pin. I used rather impolite language toward him and his operator skills. another time they ripped the moldboard right off when they hit a manhole($50000 damage) broke the sideshift casting, bent the moldboard and twisted the circle. after that we only put every second bolt in the cutting edges so it would pop the edge off instead of major damage. on that particular machine I had to replace circle teeth a couple times due to breakage from impact. those manholes could go from 2" recessed to 2" protrusion from the frost heaves. replacement manhole rings in the problem areas were changed out eventually to the ones with rounded edges which helped somewhat