# New Bed knife Issues



## ahartzell (May 18, 2017)

So I finally got around to installing the new bed knife. Took the bed bar off, removed bed knife, scraped bed bar and cleaned it. Then I installed new bed knife and reinstalled the bed bar. All done per Toro manual's instructions.

Part of removing bed bar is to back bed knife off. After replacing bed bar with new knife, I tried to adjust the bed knife to reel. Started at the leading edge and tightened until it pinched paper. Went to trailing edge and tightened until it pinched paper (although not as much). 2 issues: (1) paper didn't cut across at all (2) reel to bed knife contact seemed excessive.

I backed it off just a few clicks and then backlapped. Readjusted clearance once again. This time, I got it to pinch paper and cut from trailing edge all the way across with the exception of the last 1" or so of trailing edge. I tightened it more until it seemed to pinch paper, but it doesn't cut there and once again the contact seems excessive.

Super frustrated right now :evil: So much that I've considered: buying new reel mower or going back to rotary


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## SCGrassMan (Dec 17, 2017)

Couple of questions, and I'm not an expert, but I know what my questions would be:

1.) Why did you replace the bedknife?
2.) Why did you not replace/sharpen the reel?
3.) Does the reel cut paper when sliding across the blades?


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## ahartzell (May 18, 2017)

SCGrassMan said:


> Couple of questions, and I'm not an expert, but I know what my questions would be:
> 
> 1.) Why did you replace the bedknife?
> 2.) Why did you not replace/sharpen the reel?
> 3.) Does the reel cut paper when sliding across the blades?


(1) Bed knife was very worn (and looked warped or worn unevebly)
(2) I sharpened (backlapped) the reel. Didn't replace. Not even sure when it needs to be replaced and frankly when it does, I think I'll buy another mower. They can't be fun. 
(3) As I left it tonight, it will cut paper from leading edge all the way accross except the last 1" or so of trailing edge. And I'm not really sure how much resistance there should be but it feels like there's too much reel/bed knife contact.


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## Colonel K0rn (Jul 4, 2017)

It sounds like the reel might be conical shaped through normal wear/tear. The only way to confirm that is to take measurements of the reel cylinder at multiple points along its axis, record your readings, and see if you're within the service limits of the reel. An exaggerated measurement with the center being larger would look something like this:

4.65---------4.68--------4.85-------4.70-------4.66​
Obviously, you would need to have the reel ground, to make it a concentric cylinder, conversely, it might be worn into a taper, where the measurements are small on one end, getting larger all the way across. That's what I'm thinking you might find. Either way, take some measurements, and consult the manual to see what the service limit for your reel cylinder is, and act accordingly. If it's larger than what the service limit is (mine is 4.500" so I could get it ground if it was at the 4.650 measurement) then you should be good to get it ground. The shop would also more than likely face the new bed knife (they're not always flat, and can distort when they're mounted to the bed bar) to match the reel, and then set the relief.


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## Greendoc (Mar 24, 2018)

X2 on the check for taper or an off shaped reel. A bent or distorted bedknife will transfer its defects to the reel. I keep an extra bedknife and screws on hand to swap out a bad one immediately. Backlapping when the bedknife is not good messes up the reel quickly.


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## SCGrassMan (Dec 17, 2017)

Yeah that was my first thought, is if the bedknife is all messed up, and required replacement, the reel probably took the shape of it. I think if you replace the bedknife its probably good practice to have the reel professionally sharpened as well. It's kind of like sharpening one side of a knife blade or a pair of scissors.

I would consider backlapping to be maintaining an existing good edge, rather than a replacement for sharpening. Get that reel sharpened up and I'll bet a crisp dollar it will work just fine after that.


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## Ware (Jan 28, 2017)

SCGrassMan said:


> ...I would consider backlapping to be maintaining an existing good edge, rather than a replacement for sharpening.


+1


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## ahartzell (May 18, 2017)

@Ware you know anywhere around here that does that? Lol


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## Ware (Jan 28, 2017)

ahartzell said:


> Ware you know anywhere around here that does that? Lol


PM inbound.


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## ahartzell (May 18, 2017)

Person A: recommends grinding both reel and bed knife. However he can't get to it for 2wks. My lawsn is about 80% green and will need to be cut by middle of next week (and probably sooner). He did say if I didn't care about "perfect" cut I could back off the distance and just use it and with time and adjustment they would true to each other.

Person B: recommends same. $100/hr and said it would take 2-3hr.

I have a feeling I've got my yard off the best start ever and then won't have mower :lol:


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## Colonel K0rn (Jul 4, 2017)

A prudent person might ask where they could take a certain test mower out for a test drive


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## ahartzell (May 18, 2017)

Colonel K0rn said:


> A prudent person might ask where they could take a certain test mower out for a test drive


Haha check the swardman thread. I graciously offered up my lawn for testing :lol:


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## MasterMech (Sep 24, 2017)

Why not run it until Person A can get to you? For now, just run it set to where it will cut folded (1x) copy paper. Cutting single strips of newsprint or notebook paper is the "gold standard".

Also, scrubbing the bed bar down to bare metal with scotchbrite might help.


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