diff --git a/wise_pizza/cluster.py b/wise_pizza/cluster.py
index f4e185f..d8e3251 100644
--- a/wise_pizza/cluster.py
+++ b/wise_pizza/cluster.py
@@ -1,3 +1,5 @@
+from typing import List
+
 import numpy as np
 import pandas as pd
 from sklearn.preprocessing import PowerTransformer
@@ -19,16 +21,26 @@ def guided_kmeans(X: np.ndarray, power_transform: bool = True) -> np.ndarray:
 
     if power_transform:
         if len(X[X > 0] > 1):
-            X[X > 0] = PowerTransformer(standardize=False).fit_transform(X[X > 0].reshape(-1, 1)).reshape(-1)
+            X[X > 0] = (
+                PowerTransformer(standardize=False)
+                .fit_transform(X[X > 0].reshape(-1, 1))
+                .reshape(-1)
+            )
         if len(X[X < 0] > 1):
-            X[X < 0] = -PowerTransformer(standardize=False).fit_transform(-X[X < 0].reshape(-1, 1)).reshape(-1)
+            X[X < 0] = (
+                -PowerTransformer(standardize=False)
+                .fit_transform(-X[X < 0].reshape(-1, 1))
+                .reshape(-1)
+            )
 
     best_score = -1
     best_labels = None
     best_n = -1
     # If we allow 2 clusters, it almost always just splits positive vs negative - boring!
     for n_clusters in range(3, int(len(X) / 2) + 1):
-        cluster_labels = KMeans(n_clusters=n_clusters, init="k-means++", n_init=10).fit_predict(X)
+        cluster_labels = KMeans(
+            n_clusters=n_clusters, init="k-means++", n_init=10
+        ).fit_predict(X)
         score = silhouette_score(X, cluster_labels)
         # print(n_clusters, score)
         if score > best_score:
@@ -45,3 +57,26 @@ def to_matrix(labels: np.ndarray) -> np.ndarray:
     for i in labels.unique():
         out[labels == i, i] = 1.0
     return out
+
+
+def make_clusters(dim_df: pd.DataFrame, dims: List[str]):
+    cluster_names = {}
+    for dim in dims:
+        if len(dim_df[dim].unique()) >= 6:  # otherwise what's the point in clustering?
+            grouped_df = (
+                dim_df[[dim, "totals", "weights"]].groupby(dim, as_index=False).sum()
+            )
+            grouped_df["avg"] = grouped_df["totals"] / grouped_df["weights"]
+            grouped_df["cluster"], _ = guided_kmeans(grouped_df["avg"])
+            pre_clusters = (
+                grouped_df[["cluster", dim]]
+                .groupby("cluster")
+                .agg({dim: lambda x: "@@".join(x)})
+                .values
+            )
+            # filter out clusters with only one element
+            these_clusters = [c for c in pre_clusters.reshape(-1) if "@@" in c]
+            # create short cluster names
+            for i, c in enumerate(these_clusters):
+                cluster_names[f"{dim}_cluster_{i + 1}"] = c
+    return cluster_names
diff --git a/wise_pizza/slicer.py b/wise_pizza/slicer.py
index efbf8ea..1495b67 100644
--- a/wise_pizza/slicer.py
+++ b/wise_pizza/slicer.py
@@ -10,7 +10,7 @@
 
 from wise_pizza.solve.find_alpha import clean_up_min_max, find_alpha
 from wise_pizza.make_matrix import sparse_dummy_matrix
-from wise_pizza.cluster import guided_kmeans
+from wise_pizza.cluster import make_clusters
 from wise_pizza.preselect import HeuristicSelector
 from wise_pizza.time import extend_dataframe
 from wise_pizza.slicer_facades import SliceFinderPredictFacade
@@ -192,31 +192,11 @@ def fit(
                 cluster_values = False
 
         if cluster_values:
+            self.cluster_names = make_clusters(dim_df, dims)
             for dim in dims:
-                if (
-                    len(dim_df[dim].unique()) >= 6
-                ):  # otherwise what's the point in clustering?
-                    grouped_df = (
-                        dim_df[[dim, "totals", "weights"]]
-                        .groupby(dim, as_index=False)
-                        .sum()
-                    )
-                    grouped_df["avg"] = grouped_df["totals"] / grouped_df["weights"]
-                    grouped_df["cluster"], _ = guided_kmeans(grouped_df["avg"])
-                    pre_clusters = (
-                        grouped_df[["cluster", dim]]
-                        .groupby("cluster")
-                        .agg({dim: lambda x: "@@".join(x)})
-                        .values
-                    )
-                    # filter out clusters with only one element
-                    these_clusters = [c for c in pre_clusters.reshape(-1) if "@@" in c]
-                    # create short cluster names
-                    for i, c in enumerate(these_clusters):
-                        self.cluster_names[f"{dim}_cluster_{i+1}"] = c
-                    clusters[dim] = [
-                        c for c in self.cluster_names.keys() if c.startswith(dim)
-                    ]
+                clusters[dim] = [
+                    c for c in self.cluster_names.keys() if c.startswith(dim)
+                ]
 
         dim_df = dim_df[dims]  # if time_col is None else dims + ["__time"]]
         self.dim_df = dim_df