String Trimmer Replacement Bumper Head

Features

  • Compatible with DCST980 and DCST981 trimmers
  • Accepts 0.105" (2.7 mm), 0.095" (2.4 mm) and 0.080" (2.0 mm) nylon line
  • Includes one replacement bump head

Specifications

Assembled Length 5.2 in
Assembled Width 5.2 in
Assembled Height 3.13 in

Replacement bumper head for string trimmers. Designed to be used with the DCST980 and DCST981 trimmer units (sold separately). Accepts multiple nylon line diameters for reloads.

Model Number: DWZST980

DeWalt String Trimmer Replacement Bumper Head Review

3.8 out of 5

A worn bump cap and a jammed spool were my signs it was time to retire the original head on my trimmer. I swapped in DeWalt’s bump head designed for the DCST980/DCST981, and after several weeks of trimming beds, fence lines, and a backyard that loves to sprout volunteer saplings, I’ve got a clear sense of what it does well—and where it asks for a little patience.

What it is and who it fits

This is a factory-style replacement bump-feed head meant specifically for DeWalt’s DCST980 and DCST981 trimmers. It’s a compact unit—about 5.2 inches across and just over 3 inches tall—so it stays tucked close to the guard and doesn’t make the front of the tool feel nose-heavy. Importantly, this is not a universal head. If you’re running a different DeWalt trimmer, particularly older or newer series with different shafts or thread patterns, don’t assume it will fit. On my DCST980, it threaded on without drama and locked up securely with the spindle as expected.

The head accepts three common line diameters: 0.080, 0.095, and 0.105 inch. That flexibility matters. I keep 0.095 as my default—stout enough for light brush, but kind to battery runtime. When I cut back overgrown patches near a stone wall, I bump up to 0.105 to reduce breakoffs. For weekly lawn edges and delicate beds, 0.080 is perfectly fine and a bit quieter.

Installation: straightforward if you slow down

Out of the package, mine arrived assembled and ready to load. Here’s the process that worked well for me:

  • Pull the battery, flip the trimmer, and lock the spindle.
  • Remove the old head (note the direction—it can be opposite of what muscle memory expects).
  • Thread the new head on by hand first to avoid cross-threading. Then snug it down while holding the spindle lock.

Two notes that made life easier:
- Don’t over-tighten. These heads are designed to self-tighten in use.
- Clean the shaft threads before installation. Any grit or grass sap makes the first removal later more frustrating.

The included instructions were adequate but terse. If you haven’t swapped a trimmer head before, expect to spend a couple of extra minutes studying the exploded diagram and feeling for that first clean thread engagement.

Loading line: not a quick-load, but easy once you get the rhythm

This is a traditional spool-and-cap design—no push-through quick-load feature. You’ll remove the cap, wind the line by hand, and snap the cap back on. If you wind neatly, the feed is reliable and the line doesn’t weld under heat. My routine:

  1. Cut two equal lengths of line (I stay around 12–15 feet total for 0.095; less for 0.105, more for 0.080).
  2. Check the arrow on the spool and wrap both strands smoothly side-by-side, not crossing them.
  3. Leave 6–8 inches of tail per side and seat them in the retention notches before reassembling.
  4. After reinstalling the cap, pull each tail to remove slack and balance the lengths.

With that method, I rarely saw jams. The bump mechanism advanced line predictably—one or two bumps at half trigger brought the tails to cutting length without throwing out too much.

In the field: consistent feed and predictable wear

Paired with the DCST980, the bump head felt balanced and tracked edges cleanly. The cap material is dense enough to take routine knocks on concrete and fence posts without gouging. After four mowing cycles with mixed edging and brush cleanup, my cap showed scuffs but no cracks, and the spring still had a crisp return.

Feed consistency is the make-or-break for any bump head. Here, I had solid results:
- With 0.095, the head advanced cleanly and stopped feeding as soon as the tails reached the cutter on the guard.
- With 0.105, the spool capacity drops, and you need to wind more carefully to avoid binding. When loaded neatly, feed remained reliable, though the heavier line needs a firmer bump to advance.
- With 0.080, the feed is effortless, but the line is more prone to breakoffs if you hit chain link or brick at high rpm.

One quirk: the very first full spool I ran needed a few early bumps to find its rhythm. After that small break-in, the mechanism settled down.

Build quality and serviceability

The housing plastic feels robust and better damped than many third-party heads I’ve used. The cap snaps positively into place and removes without tools, which is what you want when you’re mid-job and need to re-tension or clear a tangle. There aren’t any extra frills—no windows or quick-thread features—but the simplicity pays off when you need to clean things out. Pop the cap, pull the spool, tap out debris, and keep going.

I also appreciate that the overall diameter is modest. A wider head can be nice for line capacity, but it’s more likely to clip landscape stones or fence hardware. This size strikes a good balance.

Performance tips that actually help

  • Pre-stretch your line: Tug each length firmly before winding. It reduces shrinkage that can lead to a loose wrap and early jams.
  • Don’t overfill: Especially with 0.105. Leave a few millimeters from the spool lip so the line can expand under heat without binding.
  • Use a dab of dry silicone spray on the spool channels: It cuts down on line welding during long, hot sessions.
  • Bump at half throttle: Advancing line at full rpm can fling out too much at once and put unnecessary stress on the mechanism.
  • Keep the guard cutter sharp: If it’s dull, you’ll over-advance and waste line.

What I liked

  • Factory fit on the DCST980/DCST981 with no adapters or guesswork.
  • Supports three line sizes, which lets me tailor for delicate edging or rough cleanup.
  • Smooth, predictable bump action once loaded correctly.
  • Sturdy cap that survives routine taps on hard surfaces.
  • Simple, tool-free serviceability in the field.

What could be better

  • It’s not a quick-load design, so you’ll spend a few extra minutes rewinding compared to those heads.
  • Documentation could be clearer about line length guidance per diameter; getting capacity right is trial-and-error at first.
  • Compatibility is narrow by design. If you don’t own the specified trimmers, this isn’t for you.
  • The initial break-in took a few bumps before the feed felt perfectly consistent.

Who it’s for

Owners of the DCST980 or DCST981 who want a straightforward, durable bump-feed head with predictable behavior. If you value simplicity, field serviceability, and the ability to switch line diameters without swapping hardware, this head fits the bill. Landscapers who burn through spools daily may prefer a quick-load head for time savings, but for most residential and light commercial users, the manual wind is an acceptable tradeoff for reliability.

The bottom line

After multiple sessions on a mix of turf and stubborn growth, this bump head handled feeding duties without fuss, stayed balanced, and showed only normal cosmetic wear. It’s not flashy, and it won’t shave minutes off your reloads the way a quick-load head can, but once it’s wound properly it does exactly what a bump head should: advance line consistently and survive the taps.

Recommendation: I recommend this head to DCST980/DCST981 owners who prefer an OEM-style solution with solid reliability and support for multiple line sizes. The combination of straightforward installation, predictable feed, and durable construction makes it a sensible, low-drama replacement. I wouldn’t recommend it if you’re looking for a universal fit or a quick-load mechanism—there are other heads tailored to those needs—but if your priority is a compatible, dependable bump-feed setup for these specific trimmers, this one delivers.



Project Ideas

Business

Pre-Wound Head Exchange Service

Offer a swap program for crews using DCST980/981: bring in an empty bump head, leave with a pre-wound unit in their chosen line diameter. Charge a core deposit and a reload fee. This saves downtime on job sites and builds repeat customers.


Refill Subscription Kits

Sell mail-order pre-wound spools tailored to 0.080, 0.095, or 0.105 inch line. Include a mini cutter, wipe, and quick-guide. Offer seasonal plans and a recycling envelope for worn line scraps to position it as convenient and eco-conscious.


Mobile Trimmer Tune-Up Pop-Ups

Set up at hardware stores, HOA events, or jobsite parking lots. Services include installing replacement bump heads, reloading line, spring replacements, safety checks, and quick spool lessons. Bundle discounted multi-head reloads for landscaping crews.


Accessory Design and Sales

Design and sell add-ons: spool winding jigs, wall racks for storing loaded heads, bump-cap protectors, and color-coded line ID bands. Offer both 3D-printable files and finished products via Etsy/Amazon and local shops.


Training Content + Affiliate Sales

Produce short videos and guides on line selection, reload speed tricks, and troubleshooting for DCST980/981 users. Monetize with affiliate links to bump heads, line, and accessories, and upsell your pre-wound kits or exchange service.

Creative

Bump-Feed Garden Twine Station

Convert the bump head into a stake-mounted twine dispenser for tying tomatoes, beans, and vines. Pre-wind jute or nylon twine; press the cap to advance just enough line, then cut on a small blade mounted nearby. Mount on a garden post or fence for quick, tangle-free plant tying. Use only as a static dispenser, not powered.


Paracord Craft Meter

Bench-mount the bump head as a paracord or craft line dispenser. Pre-wind different colors/diameters and add a simple measuring guide so each bump equals a set length. Ideal for bracelets, lanyards, or macramé where consistent lengths reduce waste and speed production.


Kite and Utility Line Dispenser

Make a handheld line dispenser for kites, camping guy-lines, or utility cord. The bump mechanism meters out small increments to avoid tangles and sudden pay-out. Add a wrist strap and a simple friction brake. Use only as a manual reel—do not attach to any motor.


Polywire Feeder for Temporary Fencing

Load 2–3 mm electric fence polywire and mount the bump head to a fence post driver, ATV rack, or a handheld rod. Walk your fence line and bump to release measured lengths as you clip to posts. Keeps wire tidy and speeds up temporary paddock setups.


Mechanism Cutaway Demo

Create a transparent cutaway by replacing a section of the shell with clear plastic. Label the spring, spool, and feed path for a classroom or makerspace demo on how bump-feed systems work. Great for teaching maintenance and troubleshooting.