How to use a Black and Decker strimmer
Updated: October 2026
The box is in the hall, the line is still taped to the spool, and the first job is the grass the mower missed along the fence. How to use a Black and Decker strimmer, on a UK lawn, starts with the guard and the lead, not with the throttle. A qualifying purchase can earn us a commission at no extra cost to you. Prices stay on the [Black and Decker grass trimmer comparison](/hub/lawn-and-garden-equipment/black-and-decker-grass-trimmer). Updated 22 October 2026 by Peter F., DIY and tools editor.
The box is in the hall, the line is still taped to the spool, and the first job is the grass the mower missed along the fence.
The box is in the hall, the line is still taped to the spool, and the first job is the grass the mower missed along the fence. How to use a Black and Decker strimmer, on a UK lawn, starts with the guard and the lead, not with the throttle. A qualifying purchase can earn us a commission at no extra cost to you. Prices stay on the Black and Decker grass trimmer comparison. Updated 22 October 2026 by Peter F., DIY and tools editor.
Our top picks
| Badge | Product | Line system | Edging aid | Assembly | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Black+Decker Black+Decker GL7033-GB | Automatic single line feed (AFS) | Wheel edge guide | Required | 8.6 | about £66.99 | View offer |
| Best value |  Black+Decker Black+Decker GL250-GB | Bump feed | n/a | Required | 8.2 | about £28.99 | View offer |
| Alternative |  Black+Decker Black+Decker GL360-GB | Bump feed | Not named | Not required | 8.0 | about £37.33 | View offer |
Before it spins
Fit the guard before the motor runs. On the GL250, GL310 and GL360 the manual tells you to unplug, snap the guard into place and screw it, then take the transit tape off the line. That tape is packing, not a fault.
Corded tools in this set need a UK outdoor setup. Electrical Safety First asks for a 30 mA RCD on the outdoor socket, the cable over your shoulder, and the extension fully unwound. The GL7033 title says 240 V. The small-pair manual says 230 V. Lead length is not printed on the amazon listings, so walk the route before you start and keep the spare cable behind you, not in a coil beside the head.
Cordless models skip the flex. Confirm the battery is the voltage on the tool, and take it off before you touch the head. The up to 43 minutes bullet is no-load, not a promise of how long your lawn will take.
The first cut
Stand so the head is on the grass you mean to cut, with the guard between you and the line. Switch on and let the head reach speed, then swing side to side in a shallow arc. Gravel is worse, because the line picks up stones. The line keeps spinning after you release the switch. Wait for it to stop before you put the head down or step over the cable.
The GL360 has a second handle. The GL250 listing does not. Reviewers at about 5 ft 1 in and near 6 ft both complain about shaft length. If the flex is under the head at any point, stop.
Edges, bump feed, and AFS
Edging is a slower pass along the boundary. On the GL7033 the listing names a wheel edge guide. If the booklet is missing, a guessed rotation is how people scalp the lawn edge.
On the GL250 and the GL360 you advance line by tapping the head while it is running. The GL7033 and the cordless line models print AFS. Do not bump those automatic heads. If the line has stopped coming out, the checks live on the line not feeding page.
Metal line and fishing line are forbidden in the small-pair manual. A6226-XJ is sold as 1.6 mm, Good Housekeeping measured 1.5 mm on a GL250, and maker pages print 2 mm for other models, so wind the spool that names your model.
When to stop
Stop when you cannot see the cable, or when the head hits something solid and the note of the motor changes. Unplug a corded tool before you clear a jam, refit the guard, or open the spool. A cut, crushed or taped flex is not a repair you finish with insulation tape.
A battery left on the tool while you unpick a jam is the mistake the manual pattern is written to prevent. If you have not yet chosen between a lead and a battery, that decision is the corded or cordless page.
Common questions
How do I use a Black and Decker strimmer for the first time?
Unplug or remove the battery, fit the guard, take the transit tape off the line, and put the cable through the restraint on the small corded models. Wear glasses, ear protection, long trousers and closed shoes. Put the RCD in the outdoor socket, keep the lead over your shoulder, and take long grass from the top in small swings. Wait for the line to stop spinning before you set the tool down.
Where does the cable go?
Over your shoulder, then through the restraint on the GL250 and GL360, so the working end cannot fall into the line. Electrical Safety First wants the extension fully unwound and a 30 mA RCD on the outdoor socket. The small-pair manual allows up to 30 m of 1.5 mm² HO5VV-F. Amazon does not print a lead length for these listings, so you still walk the border before you start.
Do I bump an automatic-feed head?
No. Bump feed, tapping the head while it is running, is the GL250 and GL360 manual method. The GL7033 and the cordless line models print AFS, automatic single-line feed. Tapping those heads is not the procedure in the sources for this page. The resin-blade kit has no line to advance.
How do I edge without scalping the lawn?
Use a shallow pass along the boundary and let a guide do the locating. The GL7033 listing names a wheel edge guide. The cordless bullets say the head flips to a wheeled edge or a guide wire. Do not copy a collar sequence from an American booklet onto a BCST918. If the line is digging a trench, lift the head.
Can I use it on wet grass?
The GL250 manual says the best result is dry grass, and line wears faster on paving. Electrical Safety First tells you not to use a grass trimmer in the rain. Wet grass also clogs the guard and hides the cable. The resin-blade listing asks about wet grass and does not answer. The rain rule from Electrical Safety First still stands for the corded tools.
What do I wear?
Glasses and ear protectors are on the GL250/GL360 appliance label, and the manual states a guaranteed 96 dB(A) for that pair. The RHS advises eye protection, long trousers and sturdy shoes when you are strimming. Closed toes matter because the line throws grit. An employer has separate noise duties under the Control of Noise at Work Regulations 2005.
Related pages
Sources
Sources from the research digest, last checked on 22 October 2026. Listing prices, stars and review counts are the amazon.co.uk captures named in the digest.
- Electrical Safety First, grass trimmers (retrieved 22.10.2026)
- Noise Emission in the Environment by Equipment for use Outdoors Regulations 2001 (retrieved 22.10.2026)
- GL250/GL360 manual (retrieved 22.10.2026)
- Black+Decker POWERCONNECT (retrieved 22.10.2026)
- HSE, noise duties for employers (retrieved 22.10.2026)
- RHS, how to garden safely (retrieved 22.10.2026)
- idealo, Black+Decker GL7033, October 2026 (retrieved 22.10.2026)
- Power Tools Direct, BCST918D1 (retrieved 22.10.2026)