Mower Blades

[StarTech]

Your image showed straight but IPL image of the spindle is showing dropped blade and that is also important to not as it changes the cutting height.

 

[djg618]

Your image showed straight but IPL image of the spindle is showing dropped blade and that is also important to not as it changes the cutting height.
View attachment 65476

Good point. I didn't catch that. Is the notches in my blade important? Just as long as I get ones with the tips bent up (high lift)? I've measured all three and the center hole is 0.982" Is that considered 15/16" (0.934") or 1"?

 

[Hammermechanicman]

What does the spindle shaft mike to?

 

[MParr]

How to measure lawn mower blades

How to Measure a Lawn Mower Blade - USA Mower Blades

usamowerblades.com

 

[sgkent]

see my post above for the link and number you might call to get blades or an answer. We were posting at the same time.

 

[StarTech]

Also if these are drop blades then the Land Pride 890-375C blades would possibly work but they are 0.320 thick.

Also the XHTZ B1LP1002 is a possible but are 20-7/8" so they might need trimming. They are 0.203 thick.

 

[djg618]

see my post above for the link and number you might call to get blades or an answer. We were posting at the same time.

That's the original manufacturer that went out of business. I did buy parts from them about 5 years ago, but I don't know if they are still selling them. I'll try again tomorrow. I did call the Atlas Lawn care number but could not get through.

 

[bertsmobile1]

No I didn't. Maybe that's where the 20-3/4" comes from.

I remeasured all three blades in case I was measuring a damaged one and all three are 20-1/2" long. Actually 1/16" shy (wear?). They are 2-1/2" wide and 1/4" thick. The hole AND the spindle measure 0.982" with a micrometer.

I'm considering buying a 0.204" thick blade in that length with a 15/16" (0.938") hole. I could open up the hole on each blade by running a conical stone in a drill from each side of the blade until it fits the arbor.

Is blade thickness that imortant? Should I stick with 1/4"?

If you bothered to check that chart then you would have seen 15/16" is a std blade hole size
Blade thickness is not important for fit
Thicker blades have a lot more momentum so will not die as quick in long tough grasses and of course will take more punishment before it bends .
Thicker blades also require more sharpening to do a good cut and reduce load on the engine . I explain this in terms of line trimmer thickness as almost every one has run line that was too thick through their trimmer at lease once .
Blade width is important as a blades that are too wide will hit each other .
Because blade length is measured diagonally a 20 x 3" blade is actually shorter than a 20 x 2.5" blade so the narrower blades may strike the sides of the deck just the same as blades that are too long will
The notch where the flute starts is there to prevent cracking & allow the flutes to be bent easily it has no functional difference in use
Unless the blade is centred in a 4 jaw chuck and you use a pedestal grinder you will not be able to open out the holes by hand.
The tinest bit off centre left right or front back will have the blade out of balance
The height between the cutting edge & the underside of the deck is CRITICAL ( yes I am shouting in the hope you will listen ) .
Too close and the deck will get overwhelmed with clippings so will clog which can quite easily cause the belt to break
Too far away and the clippings will not discharge properly and the deck will also clog all the time when cutting long grass
In both cases you will end up with blobs of cuttings all over the lawn ( we call them grass turds ) .
Pressed decks are less fussy about this but with fabricated decks with a flat steel plate on the top it is critical


If you find that you can not get original blades then buy a set of all that look like they fit.
Blades are not all that expensive particulaly when compared to buying a replacement mower .
A lot of my customers use different blades at different times in the season and in any case having a spare set ( or 2 ) of sharp blades encourages people to change them when they start to go dull
You get a much better cut & can cut a lot faster with sharp blades

 

[StarTech]

.982 is 63/64" which why you need a 1" hole. Oregon once made these blade but they longer do. Heck it has been 17 yrs since they were listed in their 2005 catalog. Back then they were a new addition.

 

[djg618]

What does the spindle shaft mike to?

It measures 0.982 also. Turns out my cheap micrometer is off a little.

Went to the local farm store and took my deck with me. Tried installing a 15/16" CH over the threaded spindle. Did not go on. I definitely have a 1" CH.