diff --git a/collects/racket/draw/private/brush.rkt b/collects/racket/draw/private/brush.rkt
index f8c65ce1ce..0d10846f5a 100644
--- a/collects/racket/draw/private/brush.rkt
+++ b/collects/racket/draw/private/brush.rkt
@@ -1,5 +1,6 @@
 #lang scheme/base
 (require scheme/class
+         ffi/unsafe/atomic
          "color.ss"
          "syntax.ss"
          "local.ss"
@@ -116,14 +117,17 @@
                    (method-name 'find-or-create-brush 'brush-list%))])
       (let ([key (vector (send col red) (send col green) (send col blue)
                          s)])
-        (let ([e (hash-ref brushes key #f)])
-          (or (and e
-                   (ephemeron-value e))
-              (let* ([f (make-object brush% col s)]
-                     [e (make-ephemeron key f)])
-                (send f s-set-key key)
-                (hash-set! brushes key e)
-                f)))))))
+        (start-atomic)
+        (begin0
+          (let ([e (hash-ref brushes key #f)])
+            (or (and e
+                     (ephemeron-value e))
+                (let* ([f (make-object brush% col s)]
+                       [e (make-ephemeron key f)])
+                  (send f s-set-key key)
+                  (hash-set! brushes key e)
+                  f)))
+          (end-atomic))))))
 
 (define the-brush-list (new brush-list%))
 
diff --git a/collects/racket/draw/private/font.rkt b/collects/racket/draw/private/font.rkt
index 77d6dc21d1..7ed9b9f1bc 100644
--- a/collects/racket/draw/private/font.rkt
+++ b/collects/racket/draw/private/font.rkt
@@ -264,14 +264,15 @@
              (vector size (and face (string->immutable-string face)) family
                      style weight underlined? smoothing size-in-pixels?)]
             (method-name 'find-or-create-font font-list%))])
-      (let ([e (hash-ref fonts key #f)])
-        (or (and e
-                 (ephemeron-value e))
-            (let* ([f (apply make-object font% (vector->list key))]
-                   [e (make-ephemeron key f)])
-              (send f s-set-table-key key)
-              (hash-set! fonts key e)
-              f))))))
+      (atomically
+       (let ([e (hash-ref fonts key #f)])
+         (or (and e
+                  (ephemeron-value e))
+             (let* ([f (apply make-object font% (vector->list key))]
+                    [e (make-ephemeron key f)])
+               (send f s-set-table-key key)
+               (hash-set! fonts key e)
+               f)))))))
 
 (define the-font-list (new font-list%))
 
diff --git a/collects/racket/draw/private/pen.rkt b/collects/racket/draw/private/pen.rkt
index 745aa29d14..085ab8a80c 100644
--- a/collects/racket/draw/private/pen.rkt
+++ b/collects/racket/draw/private/pen.rkt
@@ -1,5 +1,6 @@
 #lang scheme/base
 (require scheme/class
+         ffi/unsafe/atomic
          "color.ss"
          "syntax.ss"
          "local.ss"
@@ -159,14 +160,17 @@
                    (method-name 'find-or-create-pen 'pen-list%))])
       (let ([key (vector (send col red) (send col green) (send col blue)
                          w s c j)])
-        (let ([e (hash-ref pens key #f)])
-          (or (and e
-                   (ephemeron-value e))
-              (let* ([f (make-object pen% col w s c j)]
-                     [e (make-ephemeron key f)])
-                (send f s-set-key key)
-                (hash-set! pens key e)
-                f)))))))
+        (start-atomic)
+        (begin0
+         (let ([e (hash-ref pens key #f)])
+           (or (and e
+                    (ephemeron-value e))
+               (let* ([f (make-object pen% col w s c j)]
+                      [e (make-ephemeron key f)])
+                 (send f s-set-key key)
+                 (hash-set! pens key e)
+                 f)))
+         (end-atomic))))))
 
 (define the-pen-list (new pen-list%))