Grading Finish Blade test - the blades

[pajoube]

Charlie,
Sure appreciate what you and John have been doing.
PJ

 

[Sedgewood]

Charlie: <font color=red>Last night, I lowered the 72" deck as low as I could get it, and cut my lawn with Sedgewood's blades. The results were great.</font color=red>

Oh darn, I just finished mowing my neighbors lawn before reading this post but unfortunately lowering the deck wouldn't have been much of an option on his rough lawn. His mower broke down and he asked me to have a go to keep his grass from getting out of hand while he shops for a replacement. I made up another set of blades for the purpose. This time from some Home Depot cheapie straight blades with high lift. They did a reasonable job but in looking back on it, the humped areas that were nearly scalped were cut much better than the higher areas. Charlie's onto something here.

Drilling these cheapie blades was much easier than drilling the earlier, reversible blades Charlie is testing. The reversibles are hardened and I had to draw some temper out of them to drill them. I suppose they might last longer but they probably take twice as long to make up. I did see at Home Depot some thicker high lift blades that looked as if they too were hardened but being quite a bit more expensive I passed on them for the time being. It occurs to me that in light of the beating blades take on my rough ground that good blades may last no longer than cheap blades and may be a waste of money and extra drilling time.

I also am beginning to sense little advantage to thicker blades. After all high speed string will cut grass quite nicely. And I find the light blades will do a reasonable job on bushes. So other than for cutting really big stuff there may be no advantage to adding weight. Gotta test in the big stuff and see what happens there.

 

[Charlie_Iliff]

Today, my wife asked :"Oh, did you get the Jacobsen fixed, the grass looks great?"
That is validation of my observation about the cut quality with the deck low and Sedgewood's blades.
Please don't anyone assume that we will be recommending 1845s with rough-cut decks for golf course use. My lawn is rough, hilly and otherwise neglected, so I can't claim yet that the grooming quality will match a 425 with 60" deck, or an Exmark ZTR. It is great to see some improvement, however, and there is even a possibility I can avoid buying a Jacobsen replacement, and can look at something smaller (and cheaper) to do places a 72" deck is too clumsy.

 

[Charlie_Iliff]

Re: Finish Blade test - results

The first post in this thread has a picture attached comparing the PT rough-cut blade with one I made by cutting a Gravely blade in half and getting a 1" hole drilled in it. I did some comparison testing, which was reported earlier. and Sedgewood (John Coxon) made up some blades from thinner lawnmower blades and did comparison tests with mine. He then sent me a set of his, and I did some mowing with both.
The result, John's blades are the best so far. They beat the factory blades and mine in each type of mowing I did. With the deck at its lowest setting, they do a finish cut that is acceptable on my lawn - but not Bubenberg's customer lawns or golf courses. Set a little higher, the blades do a good smooth pasture cut, with almost no missed area. The factory blades, and to a smaller extent my blades, leave a stripe and some tufts.
The attached photo shows one of my blades and one of John's, with his on the right. His is reversible, and has the whole blade area twisted, so the whole blade outside the stump jumper lifts. Mine has a level leading edge, and bends up at the trailing edge, also creating lift, but not as much.
So, now all I have to do is wear out two sets of my blades, and I can make some like John's.
I am going down to Power Trac with Bubenberg in November, and will see what they have in the works, and give them a bit more detailed report. Maybe they'll offer a revised finish blade set for the 72" rough cut.

 

[Sedgewood]

Re: Finish Blade test - results

Charlie <font color=red>So, now all I have to do is wear out two sets of my blades, and I can make some like John's.
I am going down to Power Trac with Bubenberg in November, and will see what they have in the works, and give them a bit more detailed report. Maybe they'll offer a revised finish blade set for the 72" rough cut.</font color=red> Take one of my blades along. The new set I made up from generic hi lift lawn mower blades is straight with the back upturned edge and cuts about the same as your custom set. The reversibles are still the best so far by a fair margin, even in full grown unmowed weedy fields. And they do a surprisingly good job on saplings too - I may never put the roughcuts on again.

 

[Sedgewood]

Re: Finish Blade test - results

Charlie <font color=red>So, now all I have to do is wear out two sets of my blades, and I can make some like John's.
</font color=red> Naw, toss 'em in the junk pile in the back of the shop with PT's finish blades and all the other experimental stuff that never quite worked and see if you can improve on the reversibles. Hmm... I wonder what happens with 4 reversibles per spindle... Four per spindle had a negative effect with the roughcut blades but maybe, just maybe... naw, the power consumption issue would still be there. I think.

 

[Charlie_Iliff]

Re: Finish Blade test - results

<font color=red>Take one of my blades along.</font color=red>
John: I will take one of your blades and one of mine to Tazewell with me, and then send your set back. Even with a bit of distortion, the blades are good. A couple of them did eat major grooves in two of PT's expensive bushings. I was a bit surprised that the blades were so much harder than the bushings. I mounted them with a 1" flat washer, so they only had a little vertical play. Unfortunately, I had them all off and scrambled before I noticed the bushings, so I don't know which two caused the wear.
I've only used one side of your set, so expect a set with 50+% life to arrive by mid November.

 

[Sedgewood]

Re: Finish Blade test - results

Charlie <font color=red>I was a bit surprised that the blades were so much harder than the bushings</font color=red> Those suckers are hard! I had to draw some temper to get a drill to touch them and it was still a long slow process. guess I could have heated them some more but at the time I thought a little hardness might be a good thing. But maybe not - bushings and drilling time being as hard to come by as they are. The new hi lift set were very soft and a hole saw cut through them like butter.

And if PT wants to keep a blade for development purposes thats fine with me. It wouldn't bother me a bit if they got all the blade making fun.