Shipping charge calculation questions (wts, dims, etc)

[bugman]

Trying to understand exactly how AC (Gold R10) calculates freight charges - more pointedly, how do weights, dimensions, and multiple items play into the calculations.

It appears AC will only calculate additional shipping charges for extra items (items added to cart after one item has been added) when the "Shippable" parameter is set to "Calculate Separately".

With the "Shippable" parameter for a given item set to "Yes" (NOT "Calculate Separately"), when I add one of that item to cart, Estimated Shipping Charges that AC shows for that item match exactly what I get on the carrier's website using my account creds and the exact item parameters (weight & DIMS) that I have in AC. Good.

When I add SECOND one of that same item to cart, shipping charges do not change - shows same shipping charge for 2 items as it does for one. Not good.

If I add another DIFFERENT item (also with "Shippable" parameter set to "Yes"), then AC calculates estimated shipping charges for that last item ONLY - it ignores anything placed in cart prior to that last item. Not good.

If I change the "Shippable" parameter for an item to "Calculate Separately", AC will calculate freight correctly for any quantity of that item I add to cart (1 item = correct freight, 3 items correctly = 3x freight charge for 1 item). Good.

Then when I add ONE of ANOTHER (different) item - with its "Shippable" parameter set to "Yes" - AC will still calculate correctly (ADDS correct charge for that 2nd item). Still good.

But if I add ANOTHER one of the 2nd item (with "Shippable" set to "Yes") it is ignored - no additional freight calculated. Not good.

So... you could say "just set Shippable paramater for ALL items to "Calculate Separately", and let AC do its math. That would indeed be good... sometimes.

What happens when one (or more) item(s) can fit inside a box with another item (which happens a lot)? With all items set to "Calculate Separately", assuming AC adds together the actual weights of all the items (is this what it does?), then as long as the ACTUAL weight of the package turns out to be more than the DIM weight - no problem - freight will be calculated correctly.

But if the actual weight is LESS than the DIM wt (which happens a lot), then AC will calculate based on that too-low actual weight, and the carrier will bill me based on the DIM weight, and I lose money on the freight.

What is the best way to get reasonably accurate freight calculations the majority of the time?

And does AC use a product's DIMS at all when calculating freight, or are they completely ignored?

Any and all thoughts are appreciated!!

[Katie]

Hi,

Here is how it should be working:

- One "shippable" item in cart = we send weight AND dimensions to the carrier.

- Multiple "shippable" items in the cart = we total the weight and send only that information to carrier. It's not possible to know the dimensions.

- Any number of items in the cart set to "Calculate Separately", we send the individual weights and dimensions to the carrier and then determine the rate totals which then get shown to the customer.

One thing that is good to know is the difference between weight and dimensional weight. In Gold R9, we added a calculation pop-up on the product editing page. It allows you to see the dimensional weight of a product. You can still use the 'Shippable' setting and get accurate shipping rates by entering the dimensional weight instead of the product weight. Or, you can use the Calculate Separately option and just make sure you have dimensions entered for all your products.

Hope this helps! Let me know if you have any questions.

Thanks
Katie

[jguengerich]

Have to turned on the debug mode for one or more of the shippers to see what weight/size information is actually being sent in the rate request for each of those scenarios? If the weight sent is not increasing as you add more of the same part, or additional other parts, when the parts are set to Shippable, that would certainly indicate something is not working as expected.

[bugman]

I am not getting the behavior you describe Katie.

Katie - with items set to Calc Separately, I am getting expected behavior - freight amount shown in cart increases as expected (matches FedEx.com) as I add additional items to cart - all is good.

But with items set to Shippable = "Yes", no joy. One item in cart shows expected freight amount (in this case $20.46). But when I increase the qty of that item in the cart to 2, freight only increases to $22.51 whereas on Fedex.com when I tell it there are 2 of that same package freight increases from $20.46 to $40.92. (FYI, for the product I am using for this test I do have DIMS in Able, but they are set so that the DIM weight is equal to actual weight (both are 1 lb for this item).

This item has Options & Variants (as many of my items do), and I know which variant it is using for this test... fact that it's a variant & not the "main product" shouldn't make any difference, right? It should handle the item the same way, right??

I have also tried adding a 2nd different "Shippable = Yes" item to cart (rather increasing the qty of the existing item in cart) - same deal - freight does not increase as it should. In fact, when the 2nd item is smaller/lighter, it appears the cart is only displaying freight for that 2nd item I added and completely ignoring the 1st item that was placed in the cart.

jguengerich - I know how to turn on debug, but where how do I see the code that is being created by the rating requests? I am not a developer, but I know enough to dig around in code some & can understand some of it (IOW, I know enough to be dangerous!). Can I get that code somewhere myself or does my developer have to dig it out?

Thanks for the help guys...

[jguengerich]

As Katie mentioned, for items that are not set to calculate separately, as soon as you have more than one item the weights are simply added together and sent to the carrier as one dimensionless package with the total weight.
The difference in the freight between an order with one "Shippable=yes" item and and order with a 2nd different "shippable=yes" item is probably because with only 1 item in the order, the dimensions are sent, but as soon as you add another item (or increase the quantity of the first item), no dimensions are sent, just the total weight, which could easily return a different (lower) quote.

Also note that if you have a maximum package weight set and packaging is enabled, when the total of the "Shippable=yes" items in an order is over the maximum weight, it is split into enough equal weight (dimensionless) packages to get the weights under the maximum.

The debug output is written to a text file. IIRC, they are in the App_Data\Logs folder on the web server. They would be called UPS.log, FedEx.log, etc. The data is in XML format, so it can take a little work to find the data that is buried in all the tags, but it is there.

[bugman]

AH HA... my bad - I understood that when there were multiple "Shippable = Yes" items it was ignoring the DIMS and only using the weight, but I interpreted some of the comments to mean that it was still sending the weight of each item individually as a separate package rather than adding all the weights together as if it were one big heavy package.

Thanks Jay (and Katie), I think I have it straight(er!) in my head now, I will do some more testing/configuring.

[jguengerich]

If you really need the most accurate quotes possible for shipping in boxes that contain multiple items, you'd have to find (or create) an implementation of an algorithm that solves the "bin packing problem" (see Wikipedia for lots of technical info: https://en.wikipedia.org/wiki/Bin_packing_problem). In general, you're solving "Given boxes of sizes A, B, C,..., and items of sizes x,y,z,..., how should they be packed?" AbleCommerce doesn't include this, and I'm guessing most other general-purpose e-commerce packages don't include this either.

[bugman]

WHOA! I'm not a programmer... and although I do like to peruse an SQL programming book for fun now & then, that Wiki article made my head spin!

But thanks to you both, I am going through my products database with newfound understanding. I know I won't get everything to calculate freight PERFECTLY, but I do think I can make it better thanks to you guys.

I don't suppose there is a way to set the SHIPPABLE setting differently for different VARIANTS of one product is there? I haven't seen it so far. That would be very helpful in my case.

[jguengerich]

Yeah, you'd have to know Calculus pretty well to follow that. It was just the quickest link I could think of to explain the problem. I understood most of the first few introductory paragraphs, but I didn't even try to read the rest of it .

[foodsleuth]

RE: " I don't suppose there is a way to set the SHIPPABLE setting differently for different VARIANTS of one product is there? I haven't seen it so far. That would be very helpful in my case."

Is there a workaround for this?
We have a product with 3 variants, 2 lb, 5 lb, 50lb. The 50lb must ship separately. If I set the base item as 'ships separately' then it will apply to all three so that won't work. I set up the 50lb as a separate product with the same sku as the variant thinking maybe the variant would apply that setting.

Is the only option to make the 50lb variant a separate product an remove it as a variant?

Thanks
Barb