Magento 2 unable to save product weight programatically

Question

I am creating a new product programmatically. The product is being created but it is not saving the values for length,width,height and weight.

        $newProduct = $this->productFactory->create();
        $newProduct->setName($productDetails["name"]);
        $newProduct->setSku($productDetails["sku"]);

        $sourceItemInterface = $this->sourceItemInterfaceFactory->create();

        $sourceItemInterface->setSku($productDetails['sku']);
        $sourceItemInterface->setQuantity($productDetails['qty']);
        $sourceItemInterface->setStatus(1);
        $sourceItemInterface->setSourceCode($userSource);
        $this->sourceItemsSaveInterface->execute([$sourceItemInterface]);

        $newProduct->setStockData(
                            ['use_config_manage_stock' => 0,
                            'manage_stock' => 1,
                            'is_in_stock' => 1,
                            'qty' => $productDetails["qty"]
                        ]);
        $newProduct->setAttributeSetId(4); 
        $newProduct->setStatus(1);
        $newProduct->setVisibility(4);
        $product = $newProduct->save();

        $product->setCustomAttribute('ts_dimensions_length',$productDetails["length"]);
        $product->setCustomAttribute('ts_dimensions_width',$productDetails["width"]);
        $product->setCustomAttribute('ts_dimensions_height',$productDetails["height"]);
        $product->setWeight($productDetails["weight"]);

        $product->save();

Answer 1

try this:

    $newProduct = $this->productFactory->create();
    $newProduct->setName($productDetails["name"]);
    $newProduct->setSku($productDetails["sku"]);

    $sourceItemInterface = $this->sourceItemInterfaceFactory->create();

    $sourceItemInterface->setSku($productDetails['sku']);
    $sourceItemInterface->setQuantity($productDetails['qty']);
    $sourceItemInterface->setStatus(1);
    $sourceItemInterface->setSourceCode($userSource);
    $this->sourceItemsSaveInterface->execute([$sourceItemInterface]);

    $newProduct->setStockData(
                        ['use_config_manage_stock' => 0,
                        'manage_stock' => 1,
                        'is_in_stock' => 1,
                        'qty' => $productDetails["qty"]
                    ]);
    $newProduct->setAttributeSetId(4); 
    $newProduct->setStatus(1);
    $newProduct->setVisibility(4);
    $newProduct->setTypeId('simple'); // type of product (simple/virtual/downloadable/configurable)
    //$newProduct->setProductHasWeight(1); // 1 = simple product, 0 = virtual product
    $newProduct->setWeight($productDetails["weight"]);

    $product = $newProduct->save();
    $product->setCustomAttribute('ts_dimensions_length',$productDetails["length"]);
    $product->setCustomAttribute('ts_dimensions_width',$productDetails["width"]);
    $product->setCustomAttribute('ts_dimensions_height',$productDetails["height"]);
    $product->save();