Introduction: Magnetic Knife Rack Built Using Hard Drive Magnets (without Power Tools)
After obsessively taking apart numerous dead hard drives (befriend your IT folks, and you too can have this treasure), I've accumulated way too many of those powerful magnets. What to make? An anti-gravity device? No, that's too much work. I know -- a magnetic knife rack!
I wish I had more garage space for a table saw and a router, but ... hand tools will have to suffice.
Step 1: Supplies and Tools
Wood:
I had some "left over" poplar planks ( 1/4 x 3 x 4 -- see picture for mm measurements) and several pieces of nice looking red wood of unknown provenance (5/16 by 1/4, 15 in long). Poplar is a bit soft, so I am not sure how it's going to withstand daily use. I expect to see scratches as time goes by.
Magnets:
Hard drive magnets still attached to flat brackets. I got a bit greedy and used 7 magnets. If I had to do it over (and I just might), I would have used 6 magnets to make the bar 15 inches long. I decided to leave the magnets attached to brackets, because the brackets provided the spacing between magnets. It was easy to glue them without magnets deciding to suddenly (and violently) to attach to each other. There is a way to separate magnets from brackets -- using a large set of pliers and brute force -- that would make the bar a bit less heavy.
Tools and Supplies:
Saw (ideally with a miter box)
Sandpaper -- 220 and 400 grit
Wood glue
Superglue or epoxy
Clamps
Wood finish (or mineral oil)
Keyhole brackets for flush mounting to wall
Plastic bumpers (the kind used to protect cabinet doors) to help with flush mount and to protect wall
Step 2: Cut and Glue (and Cut and Glue)
Cut 2 identical lengths of poplar planks (1/4 x 3) for the face and the back of the bar, making sure the desired number of magnets will fit, and allowing for the inside wood (5/16 x 1/4) border (hope that made sense).
Cut narrow pieces of wood (5/16 x 1/4) and glue (using wood glue) along the perimeter on the "face" plank.
Using "superglue" or epoxy, affix magnets as shown -- with the magnet side facing down. If your workbench has a metal top (mine does), it would actually help to keep magnets in place while the glue is drying. These powerful magnets will hold the wood securely against the metal bench top.
Using wood glue, affix the "back" plank. Use plenty of clamps but be careful if you're using poplar (it is soft)!
Step 3: Sand
Spend some quality time with 220 grit and then 400 grit sandpaper. Very therapeutic!
Step 4: Finish
Finish on all sides. I used "natural" flavor of Minwax and a simple foam brush, but mineral oil could also do the trick, especially if you're using nice-looking hardwood.
Step 5: Hang and Enjoy
When I reached this step, I suddenly realized that I had no idea how to attach it to the wall. My wife (who is ALWAYS correct) pointed out that any visible hanging hardware would not look good. So, I needed something like this:
http://www.amazon.com/gp/product/B00ASVR568/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1
But I didn't have it, so I made a reasonable substitutes from scrap piece of aluminum (not worth the effort, I bought the above for "next time") and glued them to the back. I also drilled holes (using hand drill -- no power tools, remember?), to allow for the hanging screws to use the keyholes.
Attach self-adhesive plastic (or cork) bumpers, hang this baby to the wall and enjoy!
Please take a look at other magnetic bar Instructibles -- this is by far not the first one. There are some very creative and beautiful ones out there.
23 Comments
10 years ago on Step 5
I wonder if you pull off the tab of a pop can and use it for the hanger on the back. Saw this as a picture hanger online.
Reply 10 years ago on Step 5
That's a clever use of a tab. Thanks for the tip -- I will definitely keep it mind for future projects.
Reply 2 years ago
Now gotta go find the right beer...
Reply 2 years ago
I recommend Pilsner Urquell or Guiness
10 years ago on Introduction
Are the magnets not strong enough to hold the knives the right way (handles on the bottom)?
Reply 10 years ago on Introduction
I didn't realize that handles at the top was the wrong way, I thought it was just a matter of personal preference :)
However, the magnets I used are definitely strong enough to hold knives either way. Magnets from different hard drives have different strength, and I picked the stronger ones for this project.
Reply 10 years ago on Introduction
I think it's just an ergonomics/matter of preference situation. While realizing that the popular method isn't the "correct" method, I have most often seen it done handles on bottom. Are these specifically old hdd's or specifically large capacity hdd's? How do you differentiate what drives would have a stronger magnet?
Also, thanks and it's super clean looking.
Reply 10 years ago on Introduction
You are correct -- I have also mostly seen pictures of similar bars with knife blades facing up. For some reason I prefer the way I pictured it.
Unfortunately I can't exactly remember which drives yielded stronger magnets. I think (but don't quote me) that older drives had stronger magnets. They may have been pretty old RAID array drives with higher capacities.
I think weaker HD magnets could still be used with slightly thinner wood. Other instructables used hardwood and router to create a deep groove, so that technique should work pretty well. And here's another one that used a metal "flange":
http://makezine.com/projects/magnetic-knife-rack/
Thank you very much for the compliment!
Matt
Reply 4 years ago
Hi from the future...
I don't like using a knife rack with the blades downwards because I have a (possibly irrational) fear that knives will fall and stab me.
It isn't actually all that irrational because I've used more than one commercial magnetic knife rack which were barely strong enough to hold the knives. I'm thinking of the type with two narrow linear magnets. If the blade isn't already stuck to both rails when you let go -- if it's slightly out of the plane -- the momentum as it swings down to flat can actually lever it off the rail.
Also, if the rack itself is poorly mounted, you could knock it down.
Either way there's no guarantee the knife(s) would fall in the same orientation; but, again irrationally, it feels more dangerous in the point-down orientation.
4 years ago
Why do you recommend 6 magnets instead of 7?
Also do the knives end up sticking on to specific spots with magnets directly behind or can you space them out anywhere you like?
Reply 4 years ago
It's been a while since I made this, but I think a slightly shorter bar would have been nicer (at least for me). And yes, the knives tended to be "drawn" towards the magnets. These were especially strong magnets from older hard drives.
7 years ago
I use rare earth magnets. They work just as well as the hard drive magnets only without the hassle of pulling apart a bunch of old HDDs.
http://warriorwoodwork.blogspot.com/2016/04/magnetic-knife-strip-gallery.html
https://www.etsy.com/listing/158286677/walnut-magnetic-knife-rack?ref=shop_home_feat_3
Reply 7 years ago
Very nice wood and work. Rare earth magnets definitely work; however taking apart hard drives was a form of therapy, and after a while I put the magnets to good use. And they were free.
Reply 7 years ago
I have a box of those magnets. (I agree with the therapy idea, until I couldn't get those smallest Torx screws off) Now I have an idea that will help me clear off a bit of counter space. I have some cedar from a tree that fell. Maybe split it, hollow out a trough in back for the magnets and leave the front weathered.
Good idea
8 years ago on Introduction
I think this could also be used as a kick-ass key holder. Right?! Hang it right inside the door. Walk in and throw the keys at it. It should stick.
Reply 8 years ago on Introduction
I had to try it out, but turns out most keys are made of brass, which is non-magnetic. However, if you have a flat steel beer bottle opener on your key chain, it might do the trick (if you don't throw it too hard). Here're some good bottle openers/key chains:
https://www.instructables.com/id/Minnow-Survival-to...
https://www.instructables.com/id/Pocket-Sized-Key-R...
https://www.instructables.com/id/Bottle-Opener-1/
https://www.instructables.com/id/Bike-key-chain/
Reply 8 years ago on Introduction
Too bad about the keys not sticking. I tested my keys with a hard drive magent and confirmed. The keys indeed do not stick. But, the keyring itself does. I guess as long as they keys aren't being thrown at the holder that'll work as well.
9 years ago on Introduction
Whoever said that quality does not look good, never worked a day in his/her life to appreciate quality.
Having said that, let me tell you that I think this was a well written project, a very educational project, and if you're waiting for me to say it looks like crap, it's not gonna happen.
I would LOVE to have this in my kitchen! I think it is very functional, very beautiful, And I thank you for sharing this with all of us here.
Reply 9 years ago on Introduction
Thank you very much!
Reply 9 years ago on Introduction
Mr.Tzny:
I never was one to beat around the bush, so that is why I said what I said.
I believe in leting your "yes" be yes, and your "No" be no....anything else is a lie in my opinion.
Yes I honestly did enjoy reading your ible, & I have already started collecting magnets from hard drives & anywhere else I can find them....I WANT this in my home & thanks to you, I will have it eventually.
TAke care
James