A K390 Delica Dressed in Custom Titanium: Brass Dreams, Satin Backspacers and Entropic Finishes on r/knifeclub

There are two kinds of knife posts: the ones about buying, and the ones about making the knife your own. A r/knifeclub member delivered a satisfying example of the second kind on September 9, showing off a K390 Delica he dressed up with custom titanium. The centerpiece is a DLC titanium backspacer that he sanded down — taking the spine to satin because he thought it matched the build better than the black coating did. He considered an entropic finish on it too, he explained, but decided the satin would probably look better. In my opinion anyway. I like the contrast.

The Delica is the perfect canvas for this kind of project. Spyderco's lightweight lockback has been a community favorite for decades, and the K390 version adds one of the most beloved tool steels in the catalog — a semi-stainless with phenomenal edge retention that develops a working patina over time. The owner's material choices show a real eye for how knives age: he originally wanted brass so it would patina alongside the blade, but those parts appear to be made of unobtainium. Titanium was the second choice, and the satin-vs-entropic debate he worked through is one every modder recognizes.

The comment section turned the post into a mini-tutorial. One member asked the key technical question — how high do you sand before heat-treating titanium? — and the answer set the ground rules: for an entropic finish you sand to a buffed polish, otherwise the color comes out matte. Another commenter was clearly tempted, noting the entropic finish looks so good that he might buy some titanium for test runs, since he already has ferric chloride for damascus etching. The exchange captured the appeal of titanium modding: with sandpaper, a torch or a little ferric chloride, a plain part becomes a one-of-one accent that matches nothing else in the catalog.

Customizing a Delica is one of the lowest-risk entry points into knife modding — the parts are cheap, the platform is proven, and the community has documented every possible finish. Whether you go satin, brass, DLC or entropic, the goal is the same as this owner's: make a great production knife feel like yours. The K390 Delica with its satin-backed titanium spine is now exactly that — and the contrast between the black blade and the sanded backspacer is the detail that makes the whole build work.