Undershelf Drawer Remix

Searching for a storage solution for my printer tools, I came across rActive Design's rather nifty little undershelf drawer.

The design is great, as is. But I needed to fit two of them between existing shelf brackets, and they could be no wider than 150mm each. The original was too wide at 179mm, so I had to slim it down a bit. And, since I had to make this change, I decided to add a few extra alterations of my own. One thing I didn't like on the original was that the drawer slide pins had to be glued into place post-printing. I couldn't see a reason for this. Print bed size, maybe? But, whatever the reason was, adding them into the drawer body was a simple and obvious change to me. I then did the easy bit of reducing the drawer width to suit my specific needs.

After making a test print and screwing it into place, I was quite pleased. But one of my tools (a pair of forceps) kept slipping straight out of the back of the drawer. It's not really a design fault. It's just that the drawer back has to be low because of the curve that allows the drawer to pivot downwards. It takes away the top of the back wall, and makes it vulnerable to clumsy oafs like me!

My solution was to take the entire curve across the full width of the drawer, so that it curves over like a wave about to break.

I also disliked the lack of any positive indication that the drawer was fully closed, and a slightly “sloppy” feel on the runners in general. I added two small deflections into the bottom of each runner to solve the first issue, and added a small flange on each drawer pin to act as a bearing surface away from the actual drawer sides.

While I was at it, I reduced the slope angle of the runners slightly. This reduces how far the front of the drawer drops when opened, and made me feel more confident that things would stay in the drawers by themselves.

The original designer mentions that good alignment of the runners is essential. They weren't wrong, it's a nightmare! I struggled working upside down, in poor light. By the time I'd got my first drawer unit correctly aligned, the underside of my shelf resembled a pepperpot. Not only was this messy, but it also made it tricky to work out which of the (now many) holes gave the correct alignment, and it was far too easy to screw into the wrong hole by accident (Ooh er, missus!). 

So when I printed the second of the two drawers I needed, I designed a simple disposable template/jig that takes about 20 minutes to print. Whilst I was at it, I also moved the screw hole locations (I effectively mirrored them) so that I could refit the revised brackets into new holes in an undamaged area of the shelf. 

To use the template, you simply hook its lip onto the front of the shelf where you want the drawer and, keeping it aligned, drive in the screws. You can now remove the screws and discard the template. Voila! Your 6 fixing holes will be in exactly the right place, first time, every time.

I've since added two small stubs onto the template design so that it can also be used to gauge the correct distance away from any brackets or frames you might need to work round. I didn't have these when I was hanging mine, and they would have made things even easier for me - if I'd only thought of them in time!

The next step is to install the runner brackets to the shelf. Make sure the screws are tightened properly because you can't get at them with the drawer in place.

Installing the drawer unit is a little fiddly, but it's not hard. You use the natural flex of the runners to get the pins into the runner tracks (so obviously don't do this in a cold environment without warming them up first). Slide the back pins into the tracks first, then the front. Once they're in, they ain't goin' anywhere!

I highly recommend a smear of grease or Vaseline on the drawer runners and pins. You'll almost certainly find the drawer a little stiff to start off with because of the bare plastic to plastic interface.

In the original model's design the pins were perfectly circular because they were printed separately and flat on the bed. But now, because they're printed upright with the drawer, there's a little distortion and some layer line artifacts because of gravity. This can also add friction. However, if you grease them up as mentioned, and work the drawer in and out a few times, it starts to ease-up quite quickly, and it soon runs very smoothly indeed.

Thanks again to rActive Design for his model (Hope you aren't offended at my changes). The concept and design is excellent.

Happy printing!