Export thread

brand new blades seem dull like a butter knife edge to them

i have been told that is just the paint/powder coat that makes it "seem" dull but they are plenty sharp underneath after that comes off as soon as its in use

i always sharpen new blades to a razor edge before installing them but im curious what you guys think is needed or not needed

im pretty sure even dull edge blades will cut just fine albeit not cleanly

the reason i ask is, is the factory edge sharp enough or is it just formed to shape and its intended to be sharpened before using

You can put a razor's edge on the blades. But do that and mow for about 30 minutes then check the edges. The blades will round off very quickly then stay that sharpness for a long time. Some blades will stay sharper than others. The Marbain JD and Ferris blades will keep an edge longer than an MTD or AYP blades.

I never sharpen new blades, waste of the customers time and money.

Only if out balance but; of course, I use heat treated blades and any grinding reduces this treatment.

As mentioned blades will not hold a razor edge for long so it is really a waste of time unless the customer insists and is willing to pay for it. The manufaccturers could use harder steel but it would shatter on impact which would make a mess and be a severe safety hazard.

StarTech said:

Only if out balance but; of course, I use heat treated blades and any grinding reduces this treatment.

Click to expand...

Same story from me as well.
In regard to heat treated blades, they should be made from born steel so should through harden & not just surface harden.
I know some blades out of China are plain high carbon steel blades because I have seen the way several of them have shattered in use rather than bend as an alloy blade will do
The actual alloy used is a tough steel rather than a hard steel with a very similar microstructure to work hardening grades used for dozer blades but without the molly .
I regularly cut lumps out of old bar blades to make new blades for my obsolete tree shredders .
You can tell the difference when you try to drill it
Surface hardened steel will blunt the drill bit as it tries to penetrate the surface
Through hardened & work hardening grades will start to drill easily then get harder the deeper you go

Blades come from the factory meeting recommended sharpening specifications. That specification is called the 30/30 rule. Which means sharpened at a 30 degree angle with a 30 thousands blunt edge.Blades are not to be sharpened to a razor edge, as grass is very abrasive and will wear the edge very quickly down to the recommended blunt edge,

New blades are dull from the factory for liability reasons, I have been told.

steveyrock said:

New blades are dull from the factory for liability reasons, I have been told.

Click to expand...

Who ever told you that was having a lend of you.
If they needed to be any sharper they would sharpen them then put a guard over the edge like saw blades, plane blades & chisels .

My Ferris came with Marbain blades and they stayed sharp for a long time. I switched to the Gator blades with the fusion edge last year. Haven't had to sharpen them yet. Good blades cost a little more but worth it. Had a new Arnold brand blade i bent with my hands.

bertsmobile1 said:

Who ever told you that was having a lend of you.
If they needed to be any sharper they would sharpen them then put a guard over the edge like saw blades, plane blades & chisels .

Click to expand...

I will take your word on it, I am no expert on the matter. I questioned the sharpness on a new set of Marbains and thats the answer I got.

Hope you didn’t pay him to sharpen your new blades?

Rivets said:

Hope you didn’t pay him to sharpen your new blades?

Click to expand...

Hahaha, no I didn't, I sharpend them enough to get them to balance because they were out pretty much. I know, Im an idiot for doing that, right. Wink

As mentioned, a razor edge isn't what we want on a lawn mower blade. They are typically a little dull however and can be improved.

New blades should be checked for balance, straightness, and track. Any out of balance condition will rob horsepower and quality of cut.