Finish mower blades???

[winston1]

OK, I know this is a Yanmar forum but you Yanmar guys and gals have finish mowers. Going to preface my question with history. At one time I had a Cub tractor with a Woods 42" belly mower. It had a single blade that was flat as a flitter. It did an excellent job of mowing with hardly any dust making. Don't know what the blade tip speed was on it but with the 42" blade I expect it was ginning pretty fast. I now have a Woods RD60 finish mower with high lift blades. It also does an excellent job mowing but it looks like a dust storm under me in this dry weather we are having here in East Texas. Those things are like turbine fans blowing the dust. It is my understanding these high lift blades help keep the grass vertical for a better cut. I'm a little or maybe a whole lot like doubting Thomas. That is to say, I'm not fully convinced. Also it is said they help with a better discharge of the clippings. Maybe! If they were available I think I would buy a set of flat blades just for a test run. Best I can tell they are not available but I haven't completely given up.
Probably some pros and want to be pros out there with opinions so come on and lets here it.

[Roonabeck]

I second the dust storm. I always feel bad for my neighbor when it's dry and I mow.

I just took the blades off mine yesterday to sharpen them. I imagine you could use anything that had the right size bolt hole and the right blade length. Perhaps it needs to be rated for the RPM the mower runs at, too? I'm interested to see the replies you get.

[rhett]

hi "winston1",

Everything you stated about 'high-lift' blades is true about helping the finished cut. There is a disadvantage to the 'high-lift' blades not discussed, they require more energy to operate. Example, my rear discharge 'high-lift' blades are 1/4 inch thick steel, the 'high-lift' angled bends make the blades drag resistance as if it were 1 inch thick which needs more horse power.

No-Lift blades have much less resistance cutting, meaning a low pto horse power like mine cuts at faster travel speeds while requiring much less power (lower RPM's used) and wear (belt lasts longer).

Flat Blades can be sharpened on both sides making it a little easier having a sharp edge ready, just flip the blade. Flat Blades do have a mounting issue, they might require spacers to drop the blades about 3/4 of an inch because of the High Lift Deck design.

To answer your question about the dust storm, yes it would/will/is greatly reduced. The problem is finding No-Lift blades this day and age, big oil pretty much removed them from the shelves.

I did make a set of Flat Blades for testing and I have been very pleased with the results, even without the drop spacers. Finding metric Left Hand Threaded bolts is near impossible or prohibitively expensive, I need to make them also.

I did find these, 15-10209 - 21-1/2" Flat Blade
Drilling the bolt holes to 5/8 of an inch then removing 9/16 of an inch from each end for a proper fit to your RD60. A C-clamp is very handy for grind balancing the blade using the tightening pin as the balance perch.

[winston1]

rhett, I didn't state my blade particulars. The RD60 has 1" center hole and 1/2" outer holes. The outer holes aren't necessary. The blades have a 7/16" drop. Actual measurement of an Oregon replacement blade 91-584 is about 20-7/8" measuring diagonally across the blade (tip to tip). The leading edge is appx 1/4" longer than the trailing edge. I would have no problem shortening the length a little on a blade as have done that before. Might be able to handle the drilling out of the center hole to 1". The 7/16" drop is a bit of a problem. There is a 1" boss on the spindle shaft the blade fits over and then cup washers do the retaining. By putting a 7/16" spacer at that point would take away the ability of the spindle to hold the blade centered. Even though I probably mow around 2-1/2" the skirt on the mower is pretty close to the ground so without the 7/16" drop blade it would be even closer. Still listening for more suggestions and thoughts. Thanks.

[Barry 1]

Got a torch? Heat them up,and bend the angle (fan) flatter.

[shawnjvl]

The Gator Mulcher - The best mower replacement blade
I have some Gator Blades for my John deere that have very little lift. Just the teeth on the back edge. Buy them at Agri supply

Also found these flat 21" 5/8 hole
http://cgi.ebay.com/FERRIS-61-RIDING...#ht_2341wt_907

[winston1]

I am back from re inventing the wheel. I took Barry's suggestion, broke out the rose bud tip and completely flattened the uplift part of my old blades. I already had a new set on hand in case something went awry. I am purely amazed at the results. I have mowed some Bahia grass. Don't know if any of you folks have this grass or not but it is pretty tough stuff and puts up a 12" seed head in about 3 days if healthy. The grass I mowed was not extra thick. Three improvements: 1. Nearly dustless 2. half the noise from the mower. 3. Power needed difference was amazing. Just engaging the PTO without mowing pulled the engine down X amount with the uplift in place, without the uplift a lot less power to turn the blades. Very noticeable increase in length of time freewheeling after pushing in the clutch.
As for the down side I am not completely sure. I did have a few seed heads left standing (very few). I'm not sure whether I would have with the uplift in place or not. I haven't had this mower long so haven't mowed much Bahia with it. I just sort of zipped back over the left standing ones.
On the not making a difference side the grass clippings did not blow out the rear discharge but were evenly spread over the entire area when passed over. Although this grass was not overly thick there was never any notice of clogging up under the mower.
Hind sight: I wish I had just half flattened the uplift so as to have a low lift blade. I would like to see the difference. After I have used these a while I may find a set of low lift blades or possibly some of those mulchers Shawn referenced. Although I have not reached a conclusion to the matter I do not think I will go back to the high lift blade.
Enough enough

[rhett]

I am purely amazed at the results. Three improvements:
1. Nearly dustless
2. half the noise from the mower.
3. Power needed difference was amazing.
Enough enough

Glad to hear you gave it a try. With gas prices going up, maybe No-Lift blades will show back up on the shelves.

Just wait till you do hit the thicker stuff, Bump up the RPM's and cruise on through. No more down shifting or half passes

As for some stubble left standing, one day I plan to try raising the front deck leading edge a couple of inches as to not push down taller grass to low to cut. When I cut in reverse there are no stubble's left. Heck, I might even try having it open similar to a BushHogg.

Most folks 55 or older can remember a 3hp mower could tackle knee high grass. No-Lift blades made it happen, technology increased fuel consumption, more horsepower needed and equipment wear.

I started this thread http://www.tractorbynet.com/forums/c...-down-low.html a few months back, got the expected comments and let it go. Going out and trying it first hand makes one a believer. Nice to see someone else was willing to give it a try.

Thank You for the Update "winston1"

[shawnjvl]

Also wanted to note those gator blades are very thick. 1/4" steel. You could try those some time and just cut off half the height of the teeth. Keep us posted.

[winston1]

Rhett, I read your recent post and looks like there are at least 2 of us in agreement.