MB&F HM.3 Frog – The Frog Is A Prince!

HM3 Frog

Being late for an appointment is never a good start, but being late when you were only 5 minutes away to begin with is just embarrassing. Regrettably this was how I started my time with Max Büsser, of MB&F, luckily for me he is a forgiving man.

I am at MB&F headquarters to have a look for myself at the newest variation in their rather exotic stable, the (almost) all new HM3 known simply as “The Frog”.

This variation of the standard HM3 has been garnering considerable media attention both on-line and in print, especially in the Far East, so they very least I could do was go and try it on.

So it’s based on the HM3 and so that means it’s just an evolution of the existing model, right? Sounds feasible, however the best laid plans sometimes go astray. The initial design for The Frog was penned very quickly, however, that of course is where things start to become complicated.

The time indicators of the HM3 are displayed via two separate globes, and so the same was required for The Frog. However, the hour indicator was changed from 24 to 12 hours and the method of indication changed from stationary spheres with moving hands to stationary hands with moving spheres.

No problem right? Ah, no.

Actually these “small” changes required significant changes to the drive chain and some ingenious solutions.

On the HM3, moving the indicator around the stationary hour and minute markers is relatively simple. With little mass, the force required to move the indicators is very small; however moving an entire dial requires considerable power which must be delivered evenly.

The solution?

HM3 Frog

A strong light material is needed, such as aluminum, which greatly reduces the mass of each sphere. However, rather than pressing the dial they decided to carve it from a block. This is much more difficult and considerably more expensive, but results in a much more consistent product.

In the original design these indicators were set under a frame that allowed you tell the time. To aid clarity the frame has been dispensed with and the numbers have been directly applied to the domes, also known as the “eyes” of The Frog.

The outer cases were ground from a block of sapphire, and presented all manner of challenges; you see unless you make the radius of the curves even between the outside and the inside surfaces you end up with a lens which will look very odd indeed.

Perhaps the biggest difference between the two HM3 models is the weight, the new titanium case is considerably lighter than the previous steel one. As today’s trend is towards thinner and lighter this is very much on the mark.

There are two models available; the “Black”, limited to 12 examples, but if you don’t have yours confirmed you are too late they are already spoken for. The other has a mirrored case and is available in unlimited quantities. The other main difference between the models is the color of the rotor, powder coated blue for the standard model and green for the “Black” model.

The green version was apparently much more difficult to produce and in the right light really stands out, with the color changing between a strong green to one with a blue halo.

While some may find the design of the HM3 challenging, I prefer to see it as a strong statement. For some the price may be in the specialist collector range, it is undoubtedly a fantastic development of an already fantastic watch.

So what’s next for MB&F? Why the HM4 of course. Roll on July

Ian  Ellery
Ian Ellery is a guest contributor on The Watch Lounge. When he’s not writing about watches he presents his technology radio show in Geneva, collects vintage watches and attends auctions.


  1. Robert

    What amazes me about MB&F is the willingness to go to the very edge with each design, making the next model that much more challenging.

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