Wera Joker 6004 Self-Setting Spanners

There are tools that solve a problem, and then there are tools that make you wonder why that problem existed in the first place.

The Wera Joker 6004 sits firmly in the second camp.

I've always carried adjustable spanners because they're incredibly useful in field service. The problem is that the traditional adjustable spanner comes with compromises. You set the jaw, put it on the fastener, realise it's slightly loose, adjust it again, turn the fastener, remove the spanner, reposition it and repeat.

Wera looked at that process and apparently decided there were far too many steps involved.

The result is one of the strangest and cleverest spanners in my tool bag.

Not Really an Adjustable Spanner

Calling the Joker 6004 an adjustable spanner doesn't quite do it justice.

There's no thumbwheel to adjust.

Instead, the parallel jaws automatically and continuously adjust to the hexagonal fastener when you place the tool over it. An integrated lever mechanism then clamps the fastener between the jaws.

Put it onto a nut or bolt and it finds the size for you.

That's it.

It's one of those mechanisms that feels almost suspiciously simple when you first use it.

And in field service, that's exactly what I want.

Six Spanners, 7–32mm

The full six-piece set covers:

• XS 7–10mm
• S 10–13mm
• M 13–16mm
• L 16–19mm
• XL 19–24mm
• XXL 24–32mm

That gives the set continuous coverage from 7mm right through to 32mm, with Wera also specifying compatibility with imperial sizes and intermediate dimensions.

That's a huge range from six tools.

For somebody working out of a tool bag rather than a permanent workshop, space matters. Every tool I carry has to justify the weight and room it occupies.

Having six spanners capable of tackling such a broad range of fasteners makes the Joker 6004 incredibly useful.

Then Comes the Clever Bit: It Ratchets

This is probably my favourite feature.

Once the Joker has gripped the fastener, its mechanism allows you to turn it with a ratcheting action.

You don't have to keep completely removing the spanner, rotating it, putting it back onto the nut and repeating the process.

It's considerably quicker, particularly when you're working somewhere awkward where you can't get a conventional spanner through a large arc.

Wera's design allows a return angle of just 30 degrees, thanks partly to the rectangular prisms within the jaws.

That's where this stops feeling like an adjustable spanner and starts becoming something else entirely.

Brilliant in Tight Spaces

Anyone who works on machinery knows the fastener you need is rarely sitting proudly in front of you with acres of room around it.

It's behind something.

Under something.

Between two other things.

Or positioned approximately three millimetres beyond the point where your fingers comfortably reach.

The combination of the Joker's self-setting jaws, ratcheting action and 30-degree return angle makes it particularly good in those situations.

Instead of repeatedly removing the tool to reposition it, I can keep it engaged and work the fastener backwards and forwards.

It's a little thing that can make an irritating job considerably less irritating.

And I consider that an important engineering metric.

It Grips Rather Than Just Sits There

There's another important difference between the Joker and a conventional adjustable spanner.

The integrated lever mechanism actively clamps the fastener between the parallel jaws. Wera says this helps reduce the risk of the tool slipping or damaging the fastener.

That matters.

One of my biggest frustrations with cheaper adjustable spanners is jaw movement. You carefully adjust the tool, start applying force and suddenly there's enough play for it to slip.

Now you're looking at the freshly rounded corner of a fastener and reconsidering several of your recent life choices.

The Joker feels much more positive.

Put it on.

Let it adjust.

Apply pressure.

Go.

A Proper Field-Service Tool

This is where I think the Joker 6004 really earns its place in my bag.

In a workshop, having an enormous rack containing every conceivable size of spanner isn't particularly difficult.

As a field engineer, everything comes with me.

Tools have weight.

Tools take up space.

And every additional tool is something I'm carrying from the van, across the car park, through reception, across the site and eventually to the machine I'm actually working on.

Versatility therefore becomes incredibly valuable.

I don't necessarily want twenty different tools if six intelligently designed ones can cover the same territory.

The Joker 6004 set covers everything from little 7mm fasteners right up to substantial 32mm ones, yet packs into a relatively compact set.

That's exactly the sort of tool engineering I appreciate.

Very Wera

There's something distinctly Wera about the whole thing.

They could have made a nicer adjustable spanner.

Instead, they questioned why an adjustable spanner needed to work the way it traditionally does.

Why manually adjust it?

Why keep removing it from the fastener?

Why carry individual sizes if one tool can securely cover several?

Those questions resulted in something that initially looks slightly odd but makes considerably more sense once it's in your hand.

It's the same reason I enjoy their screwdrivers and Hex-Plus keys.

There's usually some little piece of engineering that makes me think:

"That's clever."

The Joker 6004 has several of them.

My verdict

The Wera Joker 6004 is probably one of the more unusual tools in my everyday kit, but it's also one of the easiest to justify.

The self-setting mechanism is brilliant.

The gripping action gives me confidence on the fastener.

The ratcheting function makes repetitive work quicker.

And having six tools covering 7–32mm makes enormous sense when everything has to live inside a field engineer's tool bag.

Is a normal adjustable spanner cheaper?

Absolutely.

At the time of writing, the complete six-piece set is listed by PrimeTools at £234.99 excluding VAT / £281.99 including VAT, so this certainly isn't the budget option.

But I'm not really comparing it with a basic adjustable spanner.

I'm looking at how many fastener sizes the set covers, how quickly I can move between them and how useful the ratcheting mechanism is when I'm buried inside a piece of equipment with hardly any room to move.

From that perspective, they're superb.

• Build quality ★★★★★
• Versatility ★★★★★
• Grip ★★★★★
• Speed ★★★★★
• Tool-bag efficiency ★★★★★
• Value ★★★★☆
• Overall ★★★★★

Would I buy them again? Absolutely.