"Hollow Construction" vs. "Two Piece Construction" Irons: Honma TR P vs X

With the new TR21 X Iron Honma dares to produce a "Hollow Construction" iron for the first time in the company's history. This design has already been used by other manufacturers and allows impressive results in terms of forgiveness and ball speed. The Honma TR21 X iron is already able to compete with a number of other irons and we believe that there will be many more of these irons in the coming years.

Up to now the recipe for more forgiveness and ball speed has been a "two piece construction" as we already found it in the Honma TW747 and now also in the TR20 P. The head is partly classically forged, but is still equipped with an insert to achieve exactly this.

In contrast, the TR21 X looks like a classic blade. But it is manufactured anything but classically. Only the face of this iron is forged - this is how it differs from most of its competitors, where the face is only cast. The construction itself is also cast in the TR21 and filled in the subsequent process. It is a special plastic and tungsten in the area of the sole.

What is intended with this construction is the following: It is possible to assemble the club in the way you want, completely independent of typical forging or casting moulds. This means that as much weight as possible is concentrated on the lower part of the club, but less weight is concentrated on all other parts. Hence a light plastic and a thin shell. The tungsten insert is actually to be taken seriously with up to 73g. Probably in the future it will be even heavier and further weight will be saved in other places. This should be the "material battle" of the future in the area of these irons.

Another battle will take place in the area of the clubfaces - because these must be constructed as thin and as hard as possible. Here Honma is one of the few manufacturers who forge their clubface instead of casting it.

Our test: Honma TR20 P vs. TR21 X

So it is time to test this new technology and see how it performs against the classic, two piece construction. Let's start with the reference to the minimal different lofts. The TR20 P 7 iron has 31° while the TR21 X has 30°. This is the modern standard and for such an iron it is really necessary as we will see in a moment.

The optical differences are quite obvious: The TR21 X looks like a blade, but is actually very big and massive. Just as a Game Improvement iron should be. The sole is very wide, the clubface is large and the topline is also relatively thick. In direct comparison with the X, the TR20 P looks almost sporty - although it has to be said that for a "two piece" iron it is relatively small anyway and there are certainly larger ones on the market.

The difference in launch

Let's get to a point that is very important: many players criticise modern irons like the TR21 X because of the low lofts. They think that a 7 iron is actually a 6 iron. But apart from the fact that 30° for a 7 iron is strong but absolutely not exceptional, what counts at the end of the day is the launch. And here we have to say one thing very clearly: A "Hollow Construction" iron like the X is designed for maximum launch, which we see directly in the test. The X launches with 19.4° over 1° higher than the P although it has 1° less loft. So much for the manufacturers who would "trick" the loft.

The difference in spin

In this context, spin is also crucial. This is significantly lower with the X than with the P. 300rpm does not sound dramatic, but is clearly noticeable on the greens. Irons like the TR21 X are designed for maximum launch and less spin. This is precisely to ensure that players with a low club head speed can also achieve a higher launch and, thanks to the lower spin, can also achieve greater distances.

The result in ball speed and length

In addition, the clubface of the X is significantly "hotter". It achieves 0.5° more ball speed - and that in comparison to a two-piece iron, which is already optimised for maximum ball speed. Here, however, one can clearly see the advantage of the new design.

All in all launch, spin and ball speed provide 3m more carry and 6m more overall length. These are quite significant differences and can actually be attributed to the different construction of the irons. The club head speed, dynamic loft and efficiency are all the same.

Feel at impact

Both testers agreed that the feel of the TR21 X is exceptional. This is because it simply feels very soft, especially for an iron in the "Game Improvement" category. And that also counts for suboptimal hits, which give less clear or negative feedback. The P is already more direct in this case. As far as forgiveness is concerned, the X is also ahead. On the one hand because of the already larger clubface, but also because hits outside the sweet spot still develop very well and hardly lose any ball speed.

Conclusion of the comparison

The main question you need to ask yourself is whether you need this 6m extra length. Especially with regard to the lower spin which definitely does not make it easier to control the ball on the green. But when it comes to the launch, the TR21 X will definitely make your life easier.

Our recommendation: "Two Piece" or "Hollow Construction"?

It is not so easy to answer which design is right for you. It is best to make yourself aware of the advantages, but also the disadvantages. The big advantage of a Hollow Construction iron like the TR21 X is clearly the optimised launch, the higher ball speed, the better forgiveness and also the soft feel over the whole clubface. The main disadvantage is that much less spin is produced, which makes it difficult to control the ball when hitting the flag.

What you can say in any case: at the latest with the Honma TR21 X the Hollow Construction construction is no longer a question of money. When such a high quality iron with the best iron shafts such as those from Nippon and the in-house Vizard shafts is already available for less than 200€/iron, it is no longer possible to say that this type of iron is only suitable for big budgets only.