Cheap Amazon Filament Rack Add-on Shelf

I've created this shelf for the Simple Houseware Standard 3-Tier Slim Rolling Storage Cart which is the perfect size for a filament rack and to hold 6 reels of filament per shelf. I wanted to keep my filament under my print desk, so I was unable to keep the cart at 3 tiers (The cart is 27.4" high and my desk is only 26" high). When I took off the top self I realized it would be pretty easy to model a bottom shelf and basically create another 2 tier rack out of the left over parts. Due to the length of the actual shelf (432mm or 17") you will need to print out the part twice and then glue it together to form the shelf. This model is specifically for the bottom shelf and does not have the holes for it to be a top shelf. Please be sure to rate my profile if everything printed fine.
 

Edit 11/16: I've Added a connector panel it lines up across the width of the shelf and takes 4 or 8 4Mx12MM screws and  nuts. See Image.

Dimensions:

The model is 201.10mm(7.9") X 216mm(8.5") and the bar hole diameter is 13.15mm(.51").

Parts:

1x Simple Houseware Standard 3-Tier Slim Rolling Storage Cart - This cart does have wheels, but I didn't need them so they aren't pictured.

Glue or glue like substance. - I'd imagine you could just use duck tape to keep the two halves together.

4x or 8x 4Mx12MM screws and corresponding nuts - If you just glue the 2 halves together these screws aren't needed.

Assembly:

1. Print the shelf model twice
2. Glue the self model together or Use the connector panel with the 4Mx12mm Screws. You can see in the pick I got creative with clamps when gluing.
3. Enjoy a job well done.

Random Thoughts:

This model is specifically for the bottom shelf, as I didn't feel like figuring out a more robust way to connect the two shelf halves*. It should be easy enough if someone wanted to remix the self to have bar holes on the bottom. Also if you wanted caster wheels on the bottom of the shelf you would need to do this. *Edit 11/16 - I made a connector panel, so there you go a more robust way to connect the panels. 

I printed the shelf pictured in the images in PETG, but I'd Imagine that PLA should work just fine.

The .3mf is for a .28mm extra draft setting, as it's a filament rack sitting under a desk I didn't see a reason to print it at a finer filament layer height.

If you look closely at the model that's being held together with clamps image, you can see the bar holes look odd. That's because it's a slightly older model where the bar holes were 12mm and I hand to sand out the holes in order for the bars to fit. After several versions I settled on the 13.15mm being the proper balances between loose and tight and that's the dimensions of the bar holes in the model I've uploaded.

中国创客们大家好，希望你们喜欢我的模型。我实际上不会说或写中文，这是谷歌翻译的。