140mm Fan Joiners

thingiverse

**Updates:** 2023-06-15 I have added a few extras. First is an alternative modified side clip which may allow a little extra space for wires. I have not done a print and test of this one. Second is a double grill clip that will hold both sides of the grill with a single clip instead of printing two of the smaller clips. It may also be helpful to hold wires a little more securely against the fan. Third is a new mounting base. I had used some custom clips to mount into my old aluminium window frames but they are a little awkward to deal with. Since all my windows have a small ledge I decided to make the array, "stand alone' so it would make it easier to move from one location to another or reverse the fan air flow. The base can be used on the bottom corners of the array or extras can be added in the bottom centres of the array. They are small enough to allow the fan to sit on my relatively narrow sill. They are about 100mm wide but may not provide enough stability if the fan array is too tall. If this is the case you would need to tie the top of the array to something solid so it will not topple. The base is designed to accommodate the width of the fan (27mm) plus 2 grills (2mm ea) with a total width of 31mm. If you are not using grills you may need to add some small shims for stability. The base has a screw hole that allows you to connect t to the corner hole of the fan. 2023-06-13 I have redesigned the side and centre connectors. They are a little smaller and should fit much better. The holes are small enough for a M3 screw to fasten directly but can be drilled out if required. In my setup, I used two shorter screws for the centre parts with washers since 30mm were the longest screws I had. The 30mm are too short to also hold the grills so I have small clips that hold the outer edges of the grills. I have two versions of the side clip. One has space for a couple of wires to run through, but I had a couple of places where I needed more room so I modified the original side connector to allow extra wires to fit. Just be careful when putting in screws as the thread is partially exposed in the modified connector and could possibly cut into your wires if they are too tightly packed. The grill clips are designed to just slide on and snap into place. 2023-06-12 The clips hold the grill to the outside of the fans fine but when you have an array of fans with centre joiners the grills don't hold properly. Luckily I had some 4mm shorter bolts that screw right into the plastic centre clips. I would recommend using two shorter screws that hold the grill and the fan and screw directly into the joiners instead of a single nut and bolt, unless you have 35 to 40mm lengths. For me, because I have already printed all my grills with the larger hole, I'm leaving my outer screws M3x30 and using the plastic clips and then using M4x12 or M4x16 and screwing them directly into the plastic. I just need to print a few washers to ensure the M4 heads hold the grill in place. I have uploaded an STL of the grill with smaller holes if you are not using clips. I did try printing a push fit, stud clip to hold the centre parts in place but I could not get a nice print that didn't break easily. Maybe using a resin printer would work better for this. **NOTE** 2023-06-12 I found a typo in my CAD measurements that makes an alignment issue with some of the screw holes. Its only 0.25mm off but its too much for my liking. I have removed the STLs that this might be an issue with and will upload ones with the proper measurements as soon as I have corrected the problem. When I make those adjustments I have also decided to decrease the hole diameter slightly to make it easier to screw an M3 screw directly into the joining blocks. If you would rather have a larger hole it would then be easy to just drill the holes the size you want. This should also eliminate the need for the grill clips as the grills can then be fastened directly to the fan and joiner. 2023-06-11 None of my fans had grills which was why I ended up breaking a blade on one of them. I decided to print some grills to keep them a little safer. Since I used 30mm bolts to fasten the fans together I needed some way to connect the grill to the fan without having to replace all my fasteners so I also printed some small clips that hold the grill onto the fan. I did a few test prints and they appear to work as I want. I am now in the process of printing and testing several grills and clips to ensure they work properly in the fan array. I am using a 0.6 nozzle on my printer and found that it was really hard to get the PETG filament to print the first layer nicely since the grill lines were so thin. I finally ended up increasing the line width of the first layer to about 150% and slowed it way down. After that the first layer worked great and the other layers then had something to adhere to properly. The grill version I am using has the corner holes printed with a large diameter so they sit down over the nut and bolt heads I already have installed. If you are planning to use the bolt holes to hold the grills in place you will need smaller holes. If anyone wants an STL with smaller holes, put something in the comments and I can upload the STL for that. 2023-06-04 I found that using the 4 point clip to create double and triple arrays was a little difficult. The groove in the clip made it difficult to assemble multiple fans unless you ensured you assembled the centre fans first. In order to solve that issue I redesigned the part to avoid being forced to fit the angled corners into the clip grooves. This has several advantages. It makes the part a little smaller which uses less filament and prints faster. Without the groove the clip fits the fans a little easier. **Summary** I needed a cooling fan for a small bedroom that could mount in a window. The prices for fans was really high and the noise they make is quite intolerable so I decided to connect a bunch of old 140mm 12V case cooling fans together. I designed some small clips that fit into the corners of the fans and links them together using 30mm (or a little longer) M3 screws. If you are planning on using a protector grill then they will definitely need to be longer. 30mm just fits through the width of the fan. Of course you could decrease the size of the clip hole and use two screws that tighten directly into the plastic of the clip. The clips are designed to allow you to feed the wires along the side in a couple of different ways. They should not require supports to print. There is also a centre clip if you are wanting to fasten fans together in double or triple arrays rather than a single horizontal or vertical array. My windows are old, single pane, aluminum frames so I also designed a clip that can be used at the outside corners to hold the fan unit in the frame. The sliding portion of the window is then slid back to hold the whole unit in place. The window clips can be used in any corner and have been designed so they can be printed without supports. I chose to make a single, universal clip rather than 2 different left and right clips so it meant cutting out some material that helped hold the clip in place but they should be fine once the screw has been put in place. I wired the fans together and then use a 12v controller to manage the fan speed. The controller I have is 3-12v 2A unit so It should be able to handle several fans without too much trouble since they only draw less than 0.25A each. Wiring is pretty easy. Obviously if your fan is 2 wire, one will be 12v(+) and the other will be ground(-). If you have 3 or 4 wire fans the first wire (usually marked with a white line) is ground and the 2nd wire is 12v positive. You can just ignore the tach wire 3 or the PWM wire 4. Check your wiring before connecting them to power so you don't damage the fans. Note: I took measurements from my Arctic F14 fans which were several years old. When I went to test them out I found one didn't work and then I broke a blade on another. I switched fan blades from the one that didn't work so that was fine but I decided to order some new ones. I got a package of 5 and when I opened them I found that the design had changed slightly and the material they used on the newer models was slightly thinner. The original clips were therefore a little sloppy. I adjusted the clips to fit the newer casing a little better and hopefully that will not be an issue with the older fans.