SQ28 PRO
Concrete vibrator SQ28 PRO
Drives out air for dense, void-free pours.
View details5-minute training
5 minHow to use the concrete vibrator
Use a concrete vibrator by plunging the head in vertically, holding it 5 to 15 seconds until bubbles stop and paste rises, and withdrawing it slowly, point by point on an even grid. SIMAQ has the gasoline SQ28 PRO (Honda GX160, 38 mm head), the SQMG28 backpack unit, the electric SQVEH40 and the 110 V SQRVP1.5 mini vibrator. The head is for driving air out, not for moving concrete.
Also called: poker vibrator, immersion vibrator, internal vibrator
The immersion vibrator drives trapped air out of fresh concrete so it ends up dense, with no honeycombing. Under-vibrate and you leave voids; over-vibrate and the aggregate sinks while the paste rises.
- 01
Pick the unit and the head
No power or a big site → gasoline (SQ28 PRO) or backpack (SQMG28); indoors or noise limits → electric (SQVEH40 or the mini vibrator). Small head for thin or heavily reinforced elements; 38 mm for slabs, beams and footings.
- 02
Pour and vibrate in lifts
Place concrete in even lifts and vibrate each one before the next. Fill a tall wall or column in one go and the air at the bottom can't get out.
- 03
Insert vertical and fast
Drop the head in vertically and fast, going a little into the lift below while it's still fresh: that knits both lifts into one piece.
- 04
Hold 5–15 seconds per point
Vibrate until a thin layer of paste rises and large bubbles stop. Longer doesn't help: it segregates the aggregate.
- 05
Withdraw slowly
Pull the head out slowly so the hole closes itself. Yank it and you leave an air channel inside.
- 06
Even, close spacing
Repeat on an even grid, spacing points ~1.5× the action radius so the circles overlap. If no paste shows between two points, move them closer.
Do this
- Always insert vertically, on systematic, evenly spaced points.
- When shiny paste rises and bubbles stop → withdraw and move to the next point.
- On walls and columns, vibrate lift by lift as you pour.
- Wash the head and hose when you finish.
Avoid this
- Don't drag concrete with the head: you segregate the aggregate.
- Don't over-vibrate: water and paste rise, aggregate sinks.
- Don't hold the head against the formwork or rest it on the rebar: it marks the exposed face and loosens the steel.
- Don't yank the head out: it leaves an air channel.
Safety
- Rubber gloves and boots; you're in fresh concrete.
- Mind the cable (electric) or hot exhaust (gasoline).
- Don't force the hose into sharp bends.
Test yourself
Got it down?
Self-check
Each practice: do it or avoid it? Tap your answer.
Wash the head and hose when you finish.
Don't yank the head out: it leaves an air channel.
On walls and columns, vibrate lift by lift as you pour.
Don't over-vibrate: water and paste rise, aggregate sinks.
Always insert vertically, on systematic, evenly spaced points.
Don't drag concrete with the head: you segregate the aggregate.
When shiny paste rises and bubbles stop → withdraw and move to the next point.
Don't hold the head against the formwork or rest it on the rebar: it marks the exposed face and loosens the steel.
Equipment in this training
Apply it on these machines
SQMG28
Backpack concrete vibrator SQMG28 PRO
Drives out air for dense, void-free pours.
View details
SQVEH40
Concrete vibrator SQVEH40
Drives out air for dense, void-free pours.
View details
SQRVP1.5
Electric mini concrete vibrator
Handheld electric vibrator with flexible shaft, for columns and small pours.
View detailsBuying guides
Clear up your questions before you quote
Guide · 5 min
When and how do you cure concrete? Methods, days and mistakes
When to start curing, for how many days, with water, burlap, plastic or curing compound, and the mistakes that rob your slab or column of strength.
Read Guide · 7 minParts of a concrete vibrator: motor, coupling, hose and head
Every concrete vibrator has a motor, a coupling, a hose with a flexible shaft inside and a head that does the vibrating. What each part does, which ones wear and how to look after them so it doesn't lose power.
Read Guide · 6 minWhy does concrete honeycomb, and how do you vibrate to prevent it?
Honeycombs are trapped air and poorly consolidated mix. Why they appear, the vibrating technique that prevents them (vertical, 5–15 s, overlapping points) and which SIMAQ vibrator fits each element.
ReadFAQ
What people ask about the concrete vibrator
How long do you vibrate concrete?
5 to 15 seconds per point, until large bubbles stop and a thin layer of paste shows on the surface. Longer doesn't help: it segregates the aggregate.
How far apart are the insertion points?
On an even grid, about 1.5 times the head's action radius apart, so the circles overlap. If areas between points show no paste, move them closer.
Electric, gasoline or backpack vibrator: which one?
No power or a big site → gasoline (SQ28 PRO). Lots of moving across slabs and scaffolds → backpack (SQMG28). Indoors or noise limits → electric (SQVEH40 or the SQRVP1.5 mini vibrator). The guide on electric, gasoline or backpack vibrators compares them.
What's the most common vibrating mistake?
Using the vibrator to push concrete sideways, or yanking it out. The first separates stone from paste; the second leaves an air channel inside.
What happens if concrete isn't vibrated?
Air stays trapped: you get honeycombing, the element loses strength and the rebar is less protected. On columns and beams it shows when the forms come off.
Get a quote without leaving
Want to work it out with an advisor?
Ready for a quote?
Tell us about the job and we'll build the package. A rep replies during business hours.