TRM Neutron Frame Lock Review: A Beefier Take on a Classic

Introduction

The TRM Neutron has long been a favorite among pocket knife enthusiasts for its slim profile, lightweight feel, and the ability to swap scales on both sides. Now TRM has released a frame lock version of the Neutron 2, and it brings some meaningful changes to the formula. This review covers what is different, how it carries, and who it is really for.

Design and Construction

The Neutron Frame Lock shares the same overall dimensions as the original Neutron 2, which means it sits comfortably in the pocket with enough blade for everyday tasks without feeling oversized. The most obvious change is the construction: instead of a liner lock with replaceable scales on both sides, the frame lock version uses a single piece of titanium that forms the back handle and an integral backspacer milled directly into it.

Inside, the knife is refreshingly simple. There are phosphor bronze washers rather than bearings, a lock bar insert that also serves as an over-travel stop, and a steel detent ball. Disassembly is straightforward, requiring only T6 and T10 bits, and the knife cleans up easily. The radial machining pattern on the inside of the titanium is a nice touch, even if it is largely a byproduct of the manufacturing process.

Steel and Blade

The frame lock version runs 20CV steel, while the liner lock Neutron 2 uses MagnaCut. In practice, 20CV offers slightly better edge retention in many situations, though the difference is largely academic for most users. The blade retains the same thin, slicy geometry that made the original Neutron so well regarded for cutting tasks like opening boxes, cutting cord, and food prep.

Carry Experience

Carrying the Neutron Frame Lock for an extended period reveals its character. It feels more substantial and secure in hand than the liner lock version, which some users found too slight or delicate. The frame lock adds a small amount of weight compared to a full titanium liner lock Neutron, but the difference is minor.

One trade-off is that you can only swap the scale on one side, since the titanium frame lock side is fixed. TRM does offer a titanium scale upgrade for the other side for a modest $15, which gives the knife a matching radial pattern on both sides and a very solid feel. The brown micarta scale that ships with the knife looks handsome, especially if you oil it occasionally.

Lockup and Feel

The frame lock itself works well, though you do need to be a little more mindful of lock bar pressure when opening. If your fingers rest on the lock bar, the knife is harder to deploy. This is a common characteristic of frame locks and not a significant issue once you adjust your grip.

The lock bar insert prevents over-travel, and the overall lockup feels secure and trustworthy. The knife does not feel fragile in the way some users perceived the original liner lock Neutron. It sits between the lightweight Neutron 2 and the thicker, beefier Bulldog in terms of heft and durability.

Pricing and Value

The base frame lock model is priced at $350, with the titanium scale upgrade bringing it to $365. For comparison, the liner lock Neutron 2 starts at $295, and a titanium-handled liner lock version runs about $375. The Bulldog, TRM’s more overbuilt option, sits around $395.

That is a significant amount of money for a pocket knife, and it is the biggest downside. However, TRM knives are made in Three Rivers, Massachusetts, by a small team, and the price reflects the cost of US manufacturing. If you value supporting small American makers and want a knife that feels more robust than the standard Neutron without going full overbuilt, the price is easier to justify.

Who Should Buy It

This knife is aimed at a specific person: someone who loves everything about the Neutron, including the thin slicy blade and ergonomics, but wishes it felt a little more substantial. If the original Neutron felt too light or too petite, the frame lock version addresses that directly. It is also a good choice for those who simply prefer frame locks over liner locks.

Buying Advice

If you already own a Neutron 2 liner lock and are happy with it, there is no pressing need to upgrade. The frame lock is different rather than better, and the liner lock still offers the advantage of swappable scales on both sides and slightly lighter weight. But if you have been eyeing the Neutron and wanted a bit more heft, or if you prefer the feel of a frame lock, this is a genuinely good option.

Conclusion

The TRM Neutron Frame Lock is a well-executed variation on a classic design. It took time to understand why it exists, but once you do, it makes sense. It fills a niche between the lightweight Neutron 2 and the heavier Bulldog, offering a more durable feel without sacrificing the blade geometry that made the original so popular. It is expensive, but for the right person, it is worth every penny.