Blade Grinders?

P

porkchop

Member
Anyone have a blade grinder they recommend? I was looking at a GB 121 on ebay but cant find the company online anywhere. Maybe out of business?? I know Oregon makes a few models and there is one I see by a company called Bradley. Anyway myself along with other family members near by have three to four mowers with over 50 inch decks making 9 to 12 blades that need to be sharpened every season. I don't want to think about a file!!! I have a bench grinder but looking for something that was made to really sharpen mower blades. Thanks for your time in advance and I hope this is the right place to post this. Take care!
 
This came up in the Kubota forum last year and I posted a link to the grinder and jig I made to sharpen my blades. I have a dozen plus blades I sharpen frequently and this really simplified it.

http://www.lawnmowerforum.com/kubot...ening-i-am-not-satisfied-how-i-have-done.html

I have this grinder FREE SHIPPING JET Bench Grinder 1 HP, 3450 RPM | Grinders Stands| Northern Tool + Equipment with this pedestal Northern Industrial Grinder Stand With Drip Pan | Grinders Stands| Northern Tool + Equipment and it works just great. The pedestal allows you to use the grinder for a variety of jobs as no workbench is "in the way". I've used a sharpening jig (the board) for as long as I can remember and only to make sure I got the angle right. When I do them by hand, I get the angle inconsistent and they wear too quickly if the angle is too sharp, or it's too shallow and it doesn't cut nicely.

I also posted a youtube video of the jig which is linked in that thread.
 
It may sound like sacrilege, but I have had excellent results with a hand held 4" grinder - one of the $20 jobs. Put the blade in a vise and have at it. Grind only the one side of the blade to maintain strength, just as when it was new. Don't overdo it and don't try to get fancy; the first time you use it the thing is going to hit a stone anyway.

Balancing a blade is simpler than you might think - bang a nail into a garage stud and hang the blade from the center hole. If it consistently tips with one end down, that end is heavy and a little more needs to come off.

You can continue using a blade long after grinding the cutting edges down; all you need is enough meat to keep the blade intact. What you have to watch for will be blade fractures. The moment you see one of those, remove the blade and don't use it again.
 
TheCaffeinatedOne said:
It may sound like sacrilege, but I have had excellent results with a hand held 4" grinder - one of the $20 jobs. Put the blade in a vise and have at it. Grind only the one side of the blade to maintain strength, just as when it was new. Don't overdo it and don't try to get fancy; the first time you use it the thing is going to hit a stone anyway.

Balancing a blade is simpler than you might think - bang a nail into a garage stud and hang the blade from the center hole. If it consistently tips with one end down, that end is heavy and a little more needs to come off.

You can continue using a blade long after grinding the cutting edges down; all you need is enough meat to keep the blade intact. What you have to watch for will be blade fractures. The moment you see one of those, remove the blade and don't use it again.
Click to expand...


The nail in the wall thing is a total myth and doesn't work? I can't believe that people by into a myth like that. There is No way possible to balance something with out finding its center, that's a proven fact and in order to balance a mower blade you have to find the center of rotation.
 
Ric said:
The nail in the wall thing is a total myth and doesn't work? I can't believe that people by into a myth like that. There is No way possible to balance something with out finding its center, that's a proven fact and in order to balance a mower blade you have to find the center of rotation.
Click to expand...

Uh... That's kind of the idea, isn't it.

There's no myth. There is a chance that you won't find the center, of course; if your blade has a toothed center hole the thing will snag. And a nail provides a very small balancing point which is a bit off center. But if you can create a fulcrum, you certainly can do static balancing because of this thing called gravity.

In essence, you choose the center of rotation as the same place the mower shaft will establish it the instant the blade is mounted: in the exact in the center of the mounting hole, or as close as you can get to it. Once you have that spot established, it becomes the reference from which you balance the blade.

A more accurate way to do this would be to slide the blade on a horizontal shaft or rod approximately the same diameter as the mounting hole, perhaps held in a vise. That's instead of the nail. It could be a long socket, for instance. Find one that slides easily through the mounting hole in the blade, hold it horizontally in the vise and spray a little lube on it. Slide the blade over the socket and let go. If the blade is heavy at one end, that end will move towards the ground and you need to remove a bit of material until both ends appear evenly balanced. That's static balancing.

The nail is quick and dirty but does nearly the same thing. So will balancing the blade on a bit of pipe sitting on the top of the bench, if you can get it to stay still long enough. The point here is to remember that the only good tool is the one you actually use.
 
You must log in or register to reply here.
Back
Top