AF-100 Replacement Spool: Fit, 0.065 Rule & Install

Home Depot and Black+Decker sell AF-100 as a 0.065 in × about 30 ft, single-line, automatic-feed (AFS) spool. Shoppers often search “AF-100 replacement spool” or a brand name plus “spool,” but trimmer spools are not universal. The cartridge shape, line diameter, and feed system have to match your head.

Use this guide to:

1. Confirm AF-100 is the right part for your tool
2. Avoid putting thicker line in an AFS head
3. Swap a spool in a few minutes
4. Fix “won’t feed” before you blame the motor

→ Shop the kit we stock: AF-100 .065" × 30 ft spool for Black+Decker

1. What AF-100 actually is

• Part family: AF-100, AF-100-2, AF-100-3, AF-100-3ZP, AF-100-BKP, AF1003ZP (pack size differs; spool geometry is the same idea).
• Line: 0.065" (1.65 mm) round, typically about 30 ft per spool, single line.
• Feed: Automatic feed / AFS — designed to advance line without bumping the head on the ground.
• Not the same as: Worx WA0010 / WA0004, Ryobi AC14RL3A-style heads, or Black+Decker dual-line DF-080 systems — even when the diameter looks similar.

2. Does it fit my trimmer?

Check the rating label on the tool or the old spool. Match the model number, not “it looks close.”

Many Black+Decker LST / LSTE / NST / CST / ST / GH / BESTA / BESTE trimmers use AF-100-style AFS spools. Common examples include LST300, LST136, LST140C, LST220, GH600, BESTA510, and other models on the product compatibility list.

Quick check

• Manual says AF-100 and only .065" → you are in the right family.
• Manual names WA0010, AC14RL3A, or DF-080 → stop and buy that part instead.

Always compare your model against the Compatible models list on the AF-100 product page before ordering.

3. The 0.065 rule (why thicker line is a bad idea on AFS)

OEM manuals for AF-100 heads say to use only .065" round line. Heavier line (for example 0.080") can overload a small motor and impair automatic feed. DIY threads sometimes try thicker line because it “feels tougher.” For AF-100 AFS, the safe default is: stay on 0.065".

4. How to replace the spool

1. Remove the battery or unplug the trimmer. Wait for the head to stop.
2. Press the release tabs and pull off the spool cap.

3. Lift out the old spool. Note any spring under the spool — put it back the same way if it comes loose.
4. Clear grass and dirt from the housing and eyelets.

5. On the new spool, free a short length of line and feed it through the eyelet.
6. Seat the spool on the boss; rotate slightly until it drops in.

7. Snap the cap until the tabs click. Line should stick out a few inches.

8. Reinstall the battery and pulse the trigger outdoors to confirm feed.

Factory-wound spools usually feed more reliably than hand-rewound empties. If you rewind bulk line, wind in the arrow direction, in even layers, and do not overfill.

5. Won’t auto-feed? Checklist

• Wrong spool cartridge (0.065 alone is not enough).
• Cap not fully snapped, or spring out of place.
• Housing packed with grass; worn eyelets.
• Hand-wound too tight, reverse direction, or overfilled.
• Line UV-brittle (snaps every few seconds) — replace the spool.

Worx GT owners: feed problems are often fixed by using the correct Worx spool (WA0004 / WA0010 family), not AF-100.

6. What’s in our AF-100 kit

Our AF-100 kit includes:

• 4 × AF-100 style pre-wound spools (0.065" × 30 ft, single line, AFS)
• 1 × spool cap
• 1 × spring

Confirm your model on the compatibility list, then order.

FAQ

Are trimmer line spools universal?
No. Match the part number and head design, not diameter alone.

Where can I find replacement spools for Worx?
Use WA0010 / WA0004-style parts for Worx GT models — not AF-100.

How do I replace a string trimmer spool?
Battery off → release tabs → swap spool → feed line through the eyelet → snap the cap (see section 4 and the photos above).

Why do people soak weed eater string?
Some hope soaking softens brittle nylon. A better fix is fresh line at the correct diameter, seated on the right spool.

How long does the line last?
It depends on grass conditions and obstacles. Some users find third-party spools wear faster than older OEM — keeping spare spools on hand is normal. Step images on this page are original install illustrations, not customer photos.

What’s in the package?
Our kit clearly includes 4 spools + cap + spring. Other listings may sell 6–8 spools — check the packing list before ordering.