Digging for Goldilocks: ‘Midi’ excavators a happy medium of small size and power

The JCB 85Z-I excavator is a mid-sized earthmover that weighs approximately 9 tons

Finding the correct machine for your job site can be like Goldilocks selecting the most comfortable bed: A mix of factors that need to be ‘just right’ to provide the most value.

For certain applications, mid-sized compact (or “midi”) excavators, which combine power and torque similar to larger earthmovers with a size that allows for maneuverability similar to a mini excavator, can be just right.

Case Construction Equipment – which offers the CX75C SR and the CX80C, its two midi excavators – describes this class of machines as “built small for big jobs.”

Chris Lucas, North American product manager for excavators at JCB, said these mid-sized machines deliver on expectations of performance and power set by larger excavators in a smaller package that can move around well on job sites where space is becoming more limited.

“I think it’s kind of a balance and a bit of a ‘best of both worlds’ kind of scenario,” Lucas said. “It doesn’t work for everyone, but when it comes to commercial construction, the midi range has become exceedingly popular.”

Jonathan Tolomeo, product manager for Komatsu, agreed that the midi excavator is rising in demand.

“Tight-tail or compact excavators continue to gain in popularity because they are a great solution in confined areas,” Tolomeo said. “Midi excavators are obviously for smaller jobs where power and reliability are still a necessity.”

Let’s look at three aspects of midi excavators to determine their place in the earthmoving world.

Midi excavator weight and size

JCB’s midi excavators, including the 85Z-I, 86C-I and 90Z-I models, all weigh between 8-10 tons, and with bodies and engines larger than smaller mini excavators, the mid-sized machines pack more of a punch.

For example, JCB’s 85Z-I performs at 48kW at just 2,200 rpm, and it has 300Nm of torque, according to the manufacturer.

“You’re obviously getting more horsepower, more performance and more auxiliary flows [with that size],” Lucas said.

Komatsu classifies its midi excavators as part of its compact line, and among its models are the PC78US-10, PC88MR-10 and PC88MR-11 – which all range in weight from 8.5 to 9.5 tons.

As for those machines’ productivity, the PC88MR-11 brings 68 horsepower at 1,850 rpm, compared to a horsepower range of 24.4-38 at 2,200-2,400 rpm for Komatsu’s mini excavators.

“Midi excavators have a larger footprint and increased weights when compared to smaller excavators,” Tolomeo said. “However, this allows them a bigger work envelope and increased lift capacities. When compared to larger excavators, midi excavators are easier to transport and more versatile on tight job sites due to their compact size.”

Because of their size, midi excavators can provide value on many types of job sites.

Tolomeo said you can find these machines working on smaller road work projects and larger utility projects, as well as large landscaping jobs and multi-unit housing projects where maneuverability is a key factor.

According to Lucas, midi excavators are a great fit for land clearing and other construction-related needs municipalities have.

Elsewhere in the midi excavator subsector, Case’s two models range from 6-8.5 tons with 55.2 horsepower, and Bobcat offers the E85 compact excavator, which weighs 8.5 tons and has 65.9 horsepower.

Midi excavator attachments and features

The bump up in size also allows for more attachment options, Lucas said.

Not only can midi excavators support a wider range of attachments, but the machines can also utilize larger and more effective tools that wouldn’t be used as effectively on smaller models, which don’t have the lifting capacity of the mid-sized machines.

“So you’re definitely stepping up into more capabilities with your attachments [with midi excavators],” Lucas said.

Contractors most commonly select JCB midi excavators with breakers (or hammers), augers and hydraulic shears.

The most popular attachments for Komatsu’s midi excavators are hammers and thumbs, Tolomeo said, with hammers in particular retaining popularity throughout the industry, thanks to their effectiveness on utility job sites where aging concrete infrastructure replacement is required.

The Komatsu PC88MR-11 is a short tail swing excavator that weighs from 9-9.5 tons

According to Tolomeo, midi excavator operators can also implement thumbs to load and unload trucks, remove old pipes and install new ones, and perform other job site activities that require clamping force operations.

He added that Komatsu’s thumbs are easy to command because of their vehicles’ simple operator adjustable auxiliary hydraulics controls from the seat of the cab.

Attachments aren’t the only features that stand out when examining midi excavators.

Komatsu’s PC88MR-11, which was released earlier this year, also has a versatile swing boom feature that works independently of the cab, in addition to redesigned dozer blades, which allow the operator to back fill holes and trenches while adding stability when digging those same trenches.

Operator comfort and convenience are important, too.

“Customers and operators now expect the same level of comfort [in midi excavators] as larger excavator classes,” Tolomeo said.

That means these vehicles’ cabs need to be quiet, enclosed and climate-controlled with features such as Bluetooth radio, ergonomic proportional joysticks, comfortable seats and rearview cameras as standard equipment, according to Tolomeo.

Also, he said, Komatsu operators are able to set hydraulic pressure and flow from inside the cab.

Lucas said JCB midi excavators are designed with more convenience, maintenance and safety features such as overload sensors and telematics in mind.

“[Midi excavators] do come with a few more bells and whistles, [as well as] more features in the controls, than you would see on a mini excavator,” Lucas said.

Mini excavators still most popular

Tolomeo said that midi excavators are rising in popularity at Komatsu, but he stressed that these mid-sized machines are designed for specific job applications and are highly accepted in those areas.

Although mini excavators, which are still the smallest and most maneuverable class of earthmovers, are the most popular excavators in general, Lucas said, the 85Z-I model is JCB’s most in-demand mid-sized machine.

“The mini excavator will always be and will continue to be the most popular,” Lucas said, because space is shrinking with more development in urban and suburban areas.

Similar to the cell phone industry’s trajectory over the past few decades, the trend with excavators is to fit more capabilities into smaller packages.

“Most people want more and more compact machines,” Lucas said. “[The overall demand] is to make them smaller and smaller but also have more features and power. There’s more of a focus going toward [mini and midi excavators].”