Before you begin. This procedure is general reference information, not professional advice. Equipment varies by manufacturer, model, and year. Always follow the documentation supplied with your equipment — where it differs from this page, follow the manufacturer. Verify that you have the tools, the working conditions, and the ability to do this task safely. If anything is unclear, if the equipment is damaged, or if the task exceeds your experience, stop and use a qualified professional. You are responsible for your own safety and for the outcome. This site accepts no liability for any loss, damage, or injury arising from the use of this information.
Specifications marked unverified could not be traced to a manufacturer source. Do not rely on them — obtain the value from your equipment documentation.
Summary
An edger blade is a steel disc spinning inches from your feet, and it is held on by one nut. That makes two things matter more than the rest of the job: the blade has to be the part your machine was built for, and the nut has to go back on properly. Everything else is grass and patience. The sequence itself is short — power source off, blade locked with the pin or the spindle lock, nut off, blade off, new blade on, nut back to full tightness, pin out, check.
What this page does not have is a torque figure, and that is the finding rather than a gap. EGO's 2024 manual for its EA0800 edger attachment takes you through the whole procedure and never gives a number: the words are "securely tighten". Black+Decker's manual for the LE750 draws its blade steps as pictures. A figure of 140 in-lb circulates for that Black+Decker on sites that rehost manuals, and it could not be confirmed against Black+Decker's own document, so it is not printed here. There is one more thing worth knowing before you reach for a wrench: on the EGO attachment the blade nut is a reverse thread, and it loosens clockwise.
Necessary equipment
| Item | Note |
|---|---|
| Heavy gloves | The edge of the blade is sharp. Wear gloves for all work on the blade. |
| Eye protection | Wear eye protection for the test of the edger. |
| The wrench supplied with your edger | The manufacturer supplies the wrench for the nut on many machines. |
| The lock pin supplied with your edger | EGO uses the hex wrench as the lock pin on its edger attachment. |
| The manufacturer documentation for your edger | The documentation gives the blade part number and the direction of the thread. |
| Needle-nose pliers optional | Use pliers for the cotter pin on machines that have one. |
| Stiff brush optional | Use a brush to remove soil from the shaft and the flanges. |
| New edger blade material | Use only the blade part number in the manufacturer documentation for your model. |
| New cotter pin material | EGO supplies a new cotter pin and tells you to install a new one. |
Find the correct blade for your edger
Estimated 8 min to 26 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Read the model number on the edger.2mReport a problem with step 1, Find the correct blade for your edger
- Greenworks tells you to look below the handle first.
- The label is on the pole on many machines.
- Find the blade part number for that model in the manufacturer documentation.3mReport a problem with step 2, Find the correct blade for your edger
- EGO names one blade for the EA0800 edger attachment.
- Greenworks gives a list of the models that each blade fits.
- The makers publish a blade length and a part number. Most publish no bore size.
USE ONLY THE BLADE PART NUMBER FOR YOUR EDGER.
A blade that does not fit the flange can become loose. A loose blade can injure a person.
- Find a new blade with that part number.2mReport a problem with step 3, Find the correct blade for your edger
- Do not select a blade by its length only.
- The centre hole and the flange must also agree.
REPLACE A BLADE THAT HAS A CRACK OR A BEND.
EGO tells you not to weld or straighten such a blade. A blade with a crack can break at speed and injure a person.
- Examine the old blade before you start the work.2mReport a problem with step 4, Find the correct blade for your edger
- EGO tells you to replace a blade if its length no longer gives the depth of cut.
- EGO also tells you to replace the blade and the nut together to keep the balance.
Remove the power source
Estimated 1 min
REMOVE THE POWER SOURCE BEFORE YOU TOUCH THE BLADE.
The edger can start without warning. The blade can cut your hand.
- If the edger has a battery, remove the battery from the edger.<1mReport a problem with step 1, Remove the power source
- EGO tells you to remove the battery before all service work.
- An edger attachment takes its battery from the power head.
- If the edger has a power cord, disconnect the plug from the receptacle.<1mReport a problem with step 2, Remove the power source
- Black+Decker gives this instruction at each point that opens the blade area.
- Wait until the blade stops fully.<1mReport a problem with step 3, Remove the power source
- Black+Decker tells you to wait for the blade to stop fully.
- The blade turns for a moment after you release the switch.
Reach the blade
Estimated 5 min to 8 min
WEAR HEAVY GLOVES BEFORE YOU TOUCH THE BLADE.
The edge of the blade is sharp. The blade can cut your hand.
- Wear the heavy gloves.<1mReport a problem with step 1, Reach the blade
- EGO tells you to protect your hands with heavy gloves for all work on the blade.
- EGO also permits a cloth around the blade instead.
- Put the edger on its back with the blade up.1mReport a problem with step 2, Reach the blade
- EGO gives this position for the EA0800 edger attachment.
- Put the machine on a flat surface.
- Remove the soil and the grass from the area around the blade.2mReport a problem with step 3, Reach the blade
- Use the stiff brush.
- If your edger has a cotter pin, remove the cotter pin from the shaft.2mReport a problem with step 4, Reach the blade
- EGO uses a cotter pin through the motor shaft.
- Use the pliers to make the two feet of the pin straight.
- Discard the old cotter pin.
Remove the old blade
Estimated 8 min to 13 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Turn the blade until the lock holes align.1mReport a problem with step 1, Remove the old blade
- EGO tells you to align the slot in the inner flange with the hole in the gear case.
- Some machines have a lock button instead of a hole.
HOLD THE BLADE WITH THE LOCK PIN.
DO NOT HOLD THE BLADE WITH YOUR HAND. The wrench can slip. The blade can cut your hand.
- Put the lock pin through the aligned holes.<1mReport a problem with step 2, Remove the old blade
- EGO uses the supplied hex wrench as the lock pin.
- The pin holds the blade while you turn the nut.
- Read the direction to loosen the nut in the manufacturer documentation.2mReport a problem with step 3, Remove the old blade
- EGO tells you to loosen the nut clockwise on the EA0800 attachment.
- That nut has a reverse thread. A normal thread loosens the other way.
- Force in the wrong direction makes the nut tighter.
- Loosen the nut with the wrench in that direction.1mReport a problem with step 4, Remove the old blade
- Remove the nut and the outer flange from the shaft.<1mReport a problem with step 5, Remove the old blade
- Make a note of the direction of each part.
- Remove the old blade from the shaft.<1mReport a problem with step 6, Remove the old blade
- Remove the inner flange from the shaft.2mReport a problem with step 7, Remove the old blade
- Examine the nut, the flanges and the shaft for wear.
- EGO tells you to replace a worn part.
- Clean the shaft and the flanges.
Install the new blade
Estimated 7 min to 10 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Install the inner flange on the shaft in the correct direction.<1mReport a problem with step 1, Install the new blade
- EGO puts the bulge on the inner flange away from the gear case.
- Install the new blade on the inner flange.<1mReport a problem with step 2, Install the new blade
- Make sure that the blade sits fully on the flange.
- A blade that sits on an edge of the flange comes loose.
- Install the outer flange and the nut on the shaft.<1mReport a problem with step 3, Install the new blade
- Tighten the nut by hand in the direction from the manufacturer documentation.<1mReport a problem with step 4, Install the new blade
- EGO tightens this nut counterclockwise.
TIGHTEN THE NUT FULLY BEFORE YOU USE THE EDGER.
A loose blade can leave the machine at speed. A blade that leaves the machine can injure a person.
DO NOT USE A LONGER BAR ON THE WRENCH.
The correct wrench is the wrench from the manufacturer. A longer bar can break the nut or the shaft.
- Put the lock pin through the aligned holes again.<1mReport a problem with step 5, Install the new blade
- Tighten the nut fully with the wrench from the manufacturer.1mReport a problem with step 6, Install the new blade
- EGO gives no torque value and tells you only to tighten the nut securely.
- This page gives no torque value. Read the specifications on this page.
- If your edger uses a cotter pin, install a new cotter pin.2mReport a problem with step 7, Install the new blade
- EGO supplies a spare cotter pin with the edger attachment.
- EGO tells you to install a new pin.
- Bend the two feet of the pin in opposite directions.
Do a check before you use the edger
Estimated 4 min
- Remove the lock pin from the holes.<1mReport a problem with step 1, Do a check before you use the edger
- A machine that starts with the pin in place breaks the gear case.
- Turn the blade by hand.<1mReport a problem with step 2, Do a check before you use the edger
- Make sure that the blade turns freely.
- Keep the gloves on your hands.
- Make sure that the guard is on the edger and that it is tight.<1mReport a problem with step 3, Do a check before you use the edger
- Wear the eye protection.<1mReport a problem with step 4, Do a check before you use the edger
- Install the battery, or connect the plug to the receptacle.<1mReport a problem with step 5, Do a check before you use the edger
- Do a short test of the edger away from other persons.1mReport a problem with step 6, Do a check before you use the edger
- Black+Decker tells you to keep persons and pets at a distance of 100 feet.
- If the edger vibrates, stop the edger immediately.<1mReport a problem with step 7, Do a check before you use the edger
- Remove the power source.
- Vibration is a sign of a loose blade or a bent blade.
- Examine the blade and the nut again.
Terminology
This page uses one term for each item and holds it throughout, as ASD-STE100 requires. Equipment sellers and other guides use the names below for the same parts.
- lawn edger
- Also called: edger, grass edger, lawn edge trimmer, half moon edger, stick edger, edge hog, bed edger
- edger blade
- Also called: edging blade, edger disc, edger cutting blade, the metal disc on the edger
- flange
- Also called: washer, spacer, blade washer, blade holder, the two discs either side of the blade
- lock pin
- Also called: holding pin, locking pin, spindle lock, the pin you push in to stop it turning
- cotter pin
- Also called: split pin, safety pin, R clip, the bent wire pin through the shaft
When to use a professional
Stop if your edger has an engine. This page gives no procedure for a machine with an engine. The isolation step is different and the manufacturer gives it.
Stop if you cannot find the blade part number for your model. Do not fit a blade that is only about the correct size. Speak to the manufacturer or to a dealer.
Stop if you cannot find the direction of the thread. The nut is a reverse thread on some machines. Force in the wrong direction damages the nut and the shaft.
Stop if the shaft turns with the nut and the lock pin is in place. This is a fault in the gear case. A service dealer must look at the machine.
Stop if the flange or the shaft has damage. A worn flange cannot hold the blade. Do not fit a new blade to a worn flange. A service dealer must replace these parts.
Stop if the edger vibrates after you fit the new blade. Remove the power source. Do not use the machine. A bent shaft causes this and a dealer must repair it.
Common questions
What torque should the edger blade nut be tightened to?
This page will not give you a number, and the reason is that the makers largely do not publish one for consumer edgers. EGO's 2024 manual for the EA0800 edger attachment walks through the entire blade change and says only to tighten the nut securely, using the wrench that came in the box. Black+Decker's LE750 manual draws its blade steps as illustrations rather than text. A value of 140 in-lb for that Black+Decker is quoted all over the sites that rehost manuals, and it could not be confirmed against Black+Decker's own document, so it is not printed here. Use the manufacturer's own wrench, tighten it fully, and check it after the first cut.
Which way does the edger blade nut turn?
Look it up for your machine before you put a wrench on it, because it is not always the way you expect. EGO's instruction for the EA0800 attachment is to loosen the nut clockwise and to tighten it counterclockwise — a reverse thread, the opposite of an ordinary nut. The logic is that the drive direction then tends to tighten the nut rather than undo it, which is the same reason many blade fixings are reversed. If you lean on it the wrong way you will only do it up harder, and you may round the nut off doing it.
How do I know which replacement blade fits my edger?
By part number and by the maker's fitment list, not by measuring the old one. EGO names exactly one blade for the EA0800 attachment and publishes its blade length as 20 cm. Greenworks publishes a 7.5 in steel blade with three alternate part numbers and a list of the edger models it fits. Neither publishes the centre hole size, so a blade that matches on length can still be wrong on the bore or on the way it locates on the flange. Find the model number first — Greenworks tells owners to look below the handle, then on the pole — and work from that.
When does an edger blade actually need replacing?
When it is too short to do the job, or when it is damaged at all. EGO's wear limit is a functional one rather than a measurement: replace the blade when its length is no longer enough to keep the ground clearance and reach the depth of cut you want. Damage is a different test with no grey area — EGO says a bent or cracked blade must be replaced and must not be straightened or welded. Black+Decker's advice for getting more life out of a blade is to start each job at minimum cutting depth and increase the depth as the blade wears down.
Can I just hold the blade with my hand while I undo the nut?
No, and this is the step where people get hurt. Every one of these machines gives you a way to lock the blade — EGO has you turn the blade until a slot in the flange lines up with a hole in the gear case and then push the supplied hex wrench through both, and other edgers use a spindle lock button. A wrench that slips off a stiff nut travels fast, and your hand is on a sharpened steel disc. EGO's own instruction is to protect your hands with heavy gloves or by wrapping the blade, and to use the supplied wrench as a stabiliser.
Do I really need to take the battery out or unplug it first?
Yes. EGO's instruction is to stop the motor, wait for all moving parts to stop and remove the battery pack before inspecting, cleaning or servicing, and it states the consequence of not doing so as serious personal injury. Black+Decker prints DANGER — unplug tool, wait for blade to come to a complete stop — at every point in the LE750 manual where the blade is exposed, including the depth adjustment. The blade also keeps turning for a moment after the switch is released, which is why waiting is part of the instruction and not a courtesy.
The cotter pin came out bent. Can I reuse it?
Use a new one. EGO supplies spare cotter pins with the edger attachment and its instruction is to insert a new cotter pin and bend the two feet in opposite directions. A cotter pin works by being deformed, so straightening and reusing one is asking a fatigued piece of soft wire to hold a blade nut. They cost pennies and they are stocked in any hardware shop, in a size to match your shaft hole.
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Sources
Every specification on this page is traced to one of these sources. Tier 1 is a manufacturer document, a published standard, or a government safety authority. See Standards for the full tiering rule.
- Tier 1Operator's Manual — Edger Attachment, Model Number EA0800 / EA0820 (MNL_EGO_EA0800/EA0820_AV03.01_240820)
- Tier 1Instruction Manual — Edge Hog Landscape Edger, Cat. No. LE750 / EH1000 (Form No. 90615877)
- Tier 17.5-Inch Replacement Edger Blade (part 29182)
Revision history
Current version 1 · updated 2026-07-29 · next review due 2027-07-29
- v1 · 2026-07-29First draft. Scoped to battery and corded electric edgers and to edger attachments on a battery power head; engine machines route to the manufacturer in the boundary. Load-bearing source is EGO's 2024 EA0800/EA0820 edger attachment manual, which carries the complete blade procedure. The blade retaining torque publishes as consult-manufacturer because no source read for this page publishes one — EGO's whole instruction is 'securely tighten' — and the 140 in-lb figure that circulates for the Black+Decker LE750 exists only on manual-rehosting sites and could not be confirmed against Black+Decker's own document, so it is not printed and is recorded in the source note as unconfirmed. Thread direction, blade part number, bore size and wear limit also publish as consult-manufacturer. Three URLs that would have added a third and fourth maker — the STIHL FCS-KM manual on cdnassets (403), the same manual on ssc.stihl.com (200 but a page-image PDF with no text layer) and the RYOBI edger attachment support pages (500) — are recorded under rejected with what each would have contributed.
Corrections to this page are listed in the public corrections log. Reports that are credible and not yet verified are listed in the public errata register, and an open one renders above the step it concerns.
Comments and corrections
Found an error? A correction with a manufacturer source is applied and logged publicly. You can also write to corrections@fixchecklist.com.
Every step above carries its own report control, which tags the report with that step so a correction reaches the right place. For anything about the procedure as a whole — the order of the sections, a step that is missing, something that did not match your equipment — use this: report something about this whole procedure.