June 2013 S M T W T F S 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Hello people. What about making some filters for that nice box you have there? Hmmm ?
First, let’s review the materials and tools needed:
Some comments about the materials, starting with the magnetic strip.
The strip I have was bought as a band about 1m long by 12cm wide, so it have to be cut to a size that matches what I’m doing. It’s 2mm thick, so it’s not exactly easy to cut, but not that difficult either. If you can find a material that already comes in an appropriate width, fine. Just mind the thickness. To thin and it might warp too easily. Remember that the fabric will be slightly stretched.
The glue. The first time I tried to make a filter, I tried double sided adhesive tape. It didn’t work. Happens that tape sticks to the magstrip like a charm, but not to the kind of fabric used for pantyhoses, specially when they’re stretched, the fabric just peels off too easily. The solution I found was epoxy glue (the kind that you need to mix two components before using).
Everything else will be explained as we go.
So let’s go.
First, measure and cut the strips of magnet. If yours came as a large sheet. cut in appropriate dimensions. I think 1.5cm is nice width. The length is up to you. Since 12cm was more than adequate to my needs (the vent I’ll be covering is for an 80mm fan), the I cut perpendicular the sheet.
After all the cutting, we’re ready to start with the actual assembly. Attention the the 4th picture of the group above. See how the magstrips are arranged ? That kind of interleaving is absolutely necessary. The first filter I made didn’t have it, the result is that I have to take care so it doesn’t break at the extremities. The interleaving will give the frame enough structural integrity so you don’t have to worry.
Now a quick look at all the stuff we’ll be using:
The first step is glue the four pieces of the frame. Apply the glue at the tips and glue it all together. Remember the interleaving. to make sure you’re doing it right: if the long side of a strip have two other strips glued to it by the narrow side, you’re doing it wrong.
I don’t have a picture of this step, so let’s go to the next one. How to stick the fabric to the frame.
Bellow you can see the already assembled frame under the fabric. I found that for best results, the fabric must be slightly stretched. Not enough that it’ll warp the frame, just enough so it doesn’t form a “belly” when you hold the frame horizontally. To keep it stretched while applying glue, tape it to the desk using the masking tape.
In the shot bellow, you see a paper towel beneath the whole thing. I thought it would help contain spills, so the whole thing wouldn’t stick to the workbench. Unfortunately, the glue in the joints was still a little wet, so the paper stuck to them… Yeah, I can be stupid like that from time to time…
Anyway, after stretching the fabric over the frame, apply generous amounts of epoxy over the fabric, it’ll seep right through it. Alternatively, it may be possible to apply the epoxy over the bare frame before covering it with the fabric, but to get the best results, remember to pre-stretch it somehow.
All glued up. Now, before you get tempted to wait until the epoxy dries, don’t. In my first attempts to build this kind of thing, I found that most adhesive tapes do not stick well to thin nylon fabric; this includes duct tape (blasphemy!!!). So, to avoid it getting loose after some time, apply whatever material you want as finishing while the epoxy is still wet. This means the fabric will be trapped between the frame and the finish.
This next step is pretty straightforward. Just put a whole lot of books (or some other flat, heavy stuff) on top of everything while the glue dries, this is just to make sure it’ll be nice and flat by the end.
Half an hour should be enough. Then just cut the excess tape and fabric from the sides.
We’re almost finished now. The last step is to put a second layer of tape and wrap it around the edges of the frame. I’ll give a nice touch to it, plus it’ll prevent the whole thing from unsticking from the frame.
Done. Now just put it over a venting hole in your case. Once in a while take it out and brush the dust of with a soft brush, or just vacuum it of.
And after all that, I was kinda hungry. So I decided to have lunch:
PS: I disabled comments on this post. If you like to comment on it, do it on this reddit post.