I imported an object from blender, set every mesh of it to cast and receive shadows, but the shadows rendered are incorrect. I also merged the meshes of the object thinking this will resolve the problem, but the result is the same. The problem seems to be resolved when using side: THREE.DoubleSide, but that makes the materials darken.
LIGHT SETTINGS
light = new THREE.DirectionalLight( 0x666666, 1 );
light.position.set( 2*400, 2*300.75, 2*400);
light.position.multiplyScalar( 1.3 );
light.castShadow=true;
light.shadowMapWidth = 2048;
light.shadowMapHeight =2048;
var d = 1300;
light.shadowCameraLeft = -d;
light.shadowCameraRight = d;
light.shadowCameraTop = d;
light.shadowCameraBottom = -d;
light.shadowCameraFar = 10000;
light.shadowBias = 0.0001;
light.shadowDarkness = 0.5;
MATERIAL SETTINGS
var childTilesTexture = THREE.ImageUtils.loadTexture('texture/wood_t.jpg?v1');
childTilesTexture.wrapS = childTilesTexture.wrapT = THREE.RepeatWrapping;
child.material = new THREE.MeshPhongMaterial( { map:childTilesTexture, shininess:5, metal: false} );
SCREENSHOTS
https://i.stack.imgur.com/bsKnU.jpg
ANOTHER SCREENSHOT
As you can see, the handles are casting a shadow through the object box.