I made this for a Cooler Master Masterbox Q300L. This is a bracket for a 3.5 HDD that can be used for mounting a second HDD in your Cooler Master Masterbox Q300L.

Story: I'm building a HTPC and needed a second HDD in my case. Originally there is only room for just one 3.5 HDD in the Masterbox Q300L. So I designed a HDD bracket and placed it in front of the PSU and used the 120mm fan hole mount for assembly.

I use the 2,5 HDD bolts that came with the Masterbox Q300L. Of course you can use other bolts if needed. Just be careful with the correct size, length and wire threat when picking different bolt. For assembly on the case I intended the use of a fan bolts.

Drawing and Files: The drawings are made in Solidworks. I included a STP, IGS, 3MF, STL and original SW files for modification. Also a PDF drawing is included so you can print 1:1 and use it as a paper cutout.

When you download the file you can do anything with it. You can make changes and redesign it for personal use, I really don't care! But you are not allowed to share any of my products before or after a redesign or modification. Nor can you take credits for any modification you have done without my consult or approval.

Redesign / Updates: 1/12/2019 After my first print I made a few modifications. When mounting the 3.5 HDD it would get stuck on the 2mm Radius/Fillet. For a better fit of the 3.5 HDD the mounting holes for the HDD need to be replaced. The modifications contains a 6.4mm to 8.4mm height that create 2mm of room between the HDD and the bracket.

Made a cut-out where the HDD power plug and sate plug is connected. Gives you more room for the wires.