Not all parts available to purchase separately from Assembly Instructions?

I am going to be building a CNC that uses a lot of of X-carve parts, but there are also some parts I don’t need.

It is better for me to purchase parts separately then. For example, I am building my own controller and do not need the X-controller to use Mach3.

The problem it seems is that not all parts are available for purchase separately. Is this intentional?

I have not gone through entire assembly instructions, but here are some parts listed in the instructions, but not in the Inventables Shop:

Drag Chain Bracket (30527-05)
Button Head Cap Screw M4 x 10, There is only M3 and M5.
Washer, Split Lock M2 Stainless
etc.

I can’t answer why you can’t buy everything in part form from inventables, but I would recommend that you buy extra screws,washers, nuts, etc and other small inexpensive parts to have on hand. I did this and have an assortment of them. Hardware items can be purchased at home centers and online. I added extra extrusion to add rigidity. I bought my drag chain on Amazon. If you are building your own design, then perhaps making some of your own parts out of hardware store metal isn’t out of the question. In many cases the screw heads can be something other than button head. My guess if you bought the inventables drag chain kit, you’d get the bracket you need.

I have found that Fastenal (if you have one local) and Amazon are great for screws/washers/nuts/etc. With either I can usually have what I need either delivered or ready for pickup the next day. As Martin said, I don’t think it would be that difficult to fashion a drag chain bracket from some aluminum stock from Ace Hardware (my preferred store for it, seem to have a better selection) or HD/Lowes/Menards/Etc. I made the comment to Inventables when I purchased mine saying something similar… I could have saved a few hundred if more things were offered separately, and arranged better, since I had planned to do some major upgrades from the beginning.