Rare Earth magnets

[smoo]

Hi, My husband is making wardrobes and has given me the task of researching rare earth magnets as an alternative door catch. Has anybody used them successfully and if so, could you please tell me a) where you bought them and b) what strength they are? The wardrobe doors weigh about 7kg each - one of them will have a full length mirror attachednd they are made of tulipwood. Any advice would be gratefully received - he's quite nervous about using these but has never been very happy with the roller catches he has used in the past and wants to try something new. Thanks in advance!

 

[rileytoolworks]

Hello try e-magnetsuk.com.
They carry a decent range of sizes and pull weights and have a fair bit of info on the site.
And they offer a good service to boot.
Good luck with the build.

All the best,
Adam.

 

[smoo]

Thanks for the quick reply. If I cover the magnets with a thin veneer of wood on both the door and the cabinet frame will they still work? I'll have a look at the site now. Thanks John

 

[JakeS]

Thanks for the quick reply. If I cover the magnets with a thin veneer of wood on both the door and the cabinet frame will they still work? I'll have a look at the site now. Thanks John

Almost certainly - magnetism weakens over distance fairly quickly, but not that quickly, and rare earth magnets are seriously strong magnets.

I'd be more worried about the magnet pulling the veneer off, although it's probably an unfounded fear.


If you're unsure, then get a pair of the magnets and see how many playing cards you can insert between them before they don't hold any more.

 

[Eric The Viking]

Two quick thoughts:
1. Axminster sell a range of magnets
2. If glass (mirror) is involved, you might want to cushion the close a bit. Possibly pads or draught seal, or I used a Hafele soft-close piston (from Toolstation in packs of 10). These can be removed from the bracket, leaving a tubular fitting that can be let into the frame easily.

E.

 

[Jacob]

There are 100s of ready made magnetic catches based on rare earth magnets. I'd investigate them first.
Magnetic, roller-ball catches etc are for small stuff and beyond a certain size you start needing a moving latch operated by turning a knob or handle.

 

[ColeyS1]

Kitchen hinges out of the question ?

 

[AndyT]

I've used magnetic catches on several cupboard doors. Whether conventional block-shaped lumps or rare-earth magnets discreetly hidden in the wood, there are a few design points you might want to think about.

You have to pull quite hard to open the door - probably bending it a bit if it's a large, lightly framed one and putting extra strain on the hinges.

You can't open or close them silently.

On the plus side, magnets at top and bottom will hold a slightly twisted door straight while it's closed.

I don't like kitchen style hinges much but I expect they are really the best option nowadays, coping well with big heavy doors, self-closing without any extra latch and being adjustable for exact fit.

 

[Peter Sefton]

We use rare earth magnets in the workshop on a regular basis, as they are so neat and strong and can be hidden below veneer, plugs or leather for a soft close effect.
I wrote an article on locks for F&C
http://www.peterseftonfurnitureschool.c ... spart2.pdf

I would go for the 19mm top and bottom of the door - the more leather or veneer you put between the magnet and washer the weaker they would be. If you need more strength use a magnet-to-magnet top and bottom, but if you do glue them in.

Make sure you get the polarity around the correct way otherwise they will repel rather than attract - not so easy to correct
Cheers Peter

 

[Myfordman]

Thanks for the quick reply. If I cover the magnets with a thin veneer of wood on both the door and the cabinet frame will they still work? I'll have a look at the site now. Thanks John

If you get the magnets with a central csk hole, you can screw them into place, cover with thin veneer and no risk of them pulling out.

 

[Cheshirechappie]

I've used the magnet-covered-with-veneer trick on a workshop cupboard, and it works very well. The veneer (mine was 0.7mm thick) about halved the pull of the magnet against a small steel plate sunk flush into the inside face of the door, but not veneered over. There's enough power to hold the door closed, and they shut with a very satisfying woody clunk, rather than the metallic click you get with proprietry catches. My doors were about 36" x 18" x 3/4" thick, and I used a 10mm diameter x 5mm magnet, one per door. For full-length wardrobe doors, I might be tempted to go for something like 20mm diameter instead.

Edit to add - they're about five years old now, and show no signs of deterioration at all. Magnet power is as good as on day one.

 

[JakeS]

Magnet power is as good as on day one.

For what it's worth, magnets very rarely lose their strength by accident. You can do it on purpose to an iron/steel magnet through controlled exposure to other magnetic fields, or by a sudden physical shock (e.g. whack one with a hammer) or by heating one up too much, but they don't just wear out over time. I expect this is all true for neodynium ('rare earth') magnets as well, since they're still predominantly iron.

(I seem to recall reading that neodynium magnets rust more easily than regular steel magnets, though.

 

[smoo]

Excellent - this is all great info. He's having a go this weekend so may be back on line with more questions... or a report back on how it's going. Many thanks for replies so far it'll be a big help.

 

[Nick Gibbs]

We did a project some time ago using rare magnets, covered with veneer, as a tool rack. I've heard of them being used by the boxmaker Andrew Crawford (who runs excellent courses, www.fine-boxes.com/courses) not only as catches, but as a buffer, with the poles reversed. He has found a way of using the magnets to hold box lids tight, but also to produce a mysterious counterweight as the lid closes to soften the closing action.

Nick