Endres started at Fleischer in 1930, where he worked as an opaquer (the person who adds color to the inked celluloid sheets.)
He sat next to Jack Mercer (Popeye’s voice actor) while in this position.
Endres worked uncredited on the Betty Boop cartoons in the 1930s under the direction of Myron Waldman.
His first credit as an animator was in 1940’s Stealin’ Ain’t Honest (de-facto directed by Tom Johnson.)
Steve Muffati chose Endres to draw on Superman’s introductory film appearance, but soon after he enlisted in the Navy.
When he returned to the animation business in 1947, he essentially became Tom Johnson’s right-hand man since he animated exclusively on his cartoons until the theatrical Popeyes ceased production.
(Stealin’ Ain’t Honest, 1940)
(Kickin’ the Conga ‘Round, 1942)
Endres’s animation in the Famous cartoons possesses the circular proportions and rubbery action that were common at Fleischer.
He tended to draw characters with puffy cheek lines, especially on Bluto.
Some quirks in Endres’s drawings include shaded eyelids, droopy mouths, and alternating the eye the titular sailor squinted (usually the one away from the viewer.)
Furthermore, his shots of Popeye show the spherical nature of Popeye’s head, specifically the numerous upshots of the character.
I’d argue that besides Dave Tendlar, Endres was the “cutesy” Popeye animator.
To wrap up, Endres was a loyal and dutiful worker who liked to portray three-dimensionality in 2-D characters.
(I’ll Be Skiing Ya, 1947)
(Robin Hood-Winked, 1948)
(Quick on the Vigor, 1950)
(Spooky Swabs, 1957) (The last time we see Popeye in theaters)