# Gluing magnets into wood?



## Richard D (11 May 2010)

OK, I'm after a bit of advice here.

I'm making some wooden boxes, and the easiest way to secure the lids to the carcases is to recess small rare-earth magnets into both the sides and the lids. My worry, though, is that these are strong magnets, and the glue will need to be pretty strong to prevent them pulling straight out. Plus the magnets themselves are nickel-coated and very smooth.

PVA is clearly right out. A cyanoacrylate is going to provide a decent bond with the magnet itself, but how does it get on with wood? My preference is to try an epoxy, but I *hate* mucking about with that stuff (plus I have quite a lot of boxes to make up, which will see me having to mix up three or four batches of epoxy unless I go for something that sets more slowly than the standard Araldite).

I realise that I can moderate the magnets' strength by recessing them more deeply so that they aren't flush with each other when the box lid is closed, but assuming that I'm not going to do that, what adhesive would you use to prevent the magnets simply tearing out of their holes when they stick together so strongly?


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## WoodAddict (11 May 2010)

not too sure about the correct glue to use but just another thought - would it not be best to use a magnet in the lid and a magnetic metal in the box sides rather than magnet-on-magnet. Might be a bit less powerful but still plenty strong enough with the right magnet.

Just a thought :?


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## mailee (11 May 2010)

I have used epoxy in the past to glue rare earth magnets into wood. I scored the bqack of them with some course sandpaper first and then applied the epoxysitting them into recesses cut into the timber. These were to hold some cornice on top of wardrobes which could be removed for cleaning. HTH. :wink:


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## katellwood (11 May 2010)

there are also these should removal be needed. 

http://e-magnetsuk.com/magnets/neodymiu ... gnets.aspx


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## 9fingers (11 May 2010)

My method is to drill a deeper hole than needed for the magnet alone and then fit a csk screw in the bottom, adjusting the depth to place the magnet where needed.
During the set up the magnet can be withdrawn using another magnet.
When all is well, clean off finger grease with acetone or thinners and apply real 24hr epoxy not this 5 minute rubbish and fit the magnet.

If you decide to use one magnet in each face then don't forget to place the poles the correct may round! marking with a felt pen helps.

Bob


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## srp (11 May 2010)

Or you can drill a hole a bit deeper, put the magnet in and then cap it with a plug of matching timber. Normal pva or pu glue will easily hold the plug and keep the magnet where it belongs.


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## xy mosian (11 May 2010)

katellwood's reference:-	

http://e-magnetsuk.com/magnets/neodymiu ... gnets.aspx

This company also sell cyanoacrylate adhesive to glue the magnets to wood.

HTH
xy


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## ondablade (12 May 2010)

There's quite a few purpose developed magnet bonders around, usually for bonding ferrite or whatever to metal. There's quite a big market for them for use in loudspeaker production.

So far as i can remember from when i worked in adhesives systems R&D they are typical 2 part (handles much like an epoxy) or UV curing acrylics - usually with something in there to give a bit of flexibility.

Epoxy does the job too i think, but my lot used acrylics and i'm not sure why or if there was any advantage.

I'd be a little cautious of using a cyanoacrylate unless somebody has managed to overcome the natural disadvantages of the stuff. It'll bond all right, but the stuff is not waterproof (the cured resin is, but water unzips the bond between it and the substrate), and is very brittle meaning that it's likely to be at risk of being worked loose by differential expansion, thermal cycling, vibration or whatever...


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## oddsocks (12 May 2010)

9fingers":gp394bfi said:


> If you decide to use one magnet in each face then don't forget to place the poles the correct may round! marking with a felt pen helps.
> 
> Bob



I have two small pieces of wood about 6mm thick with a magnet (5mm) in the end of each such that the two bits of wood attract. Seeing as I used the magnets in cabinet doors one piece of wood is labelled 'door' and the other 'carcass'. I drill a snug 5mm hole then pick up a magnet with the appropriate labelled wood and use this to hold it (automatically with the correct face orientation) while I put it in the hole (I fix with just normal super glue and have had no problems).


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## AndyT (12 May 2010)

The multi-purpose building adhesives you buy in a cartridge work for this sort of thing -"No more nails" and the like. They are not all as thick and clumsy as Gripfill. Some are available in small tubes.


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## bugbear (12 May 2010)

Richard D":17hubd6v said:


> OK, I'm after a bit of advice here.



I was glueing magnets recently - small pieces of rare earth magent, extracted (recycled!) from a computer hard-drive.

I was fixing them to a small piece of Tufnol to make a pointer gadget:

http://www.knifeforums.com/forums/print ... id/871697/

I fixed the magnets with normal household Bostik:

http://www.amazon.co.uk/Bostik-All-Purp ... B0001OZI48

I let the glue dry for 24 hours.

After around 10-20 fix/remove cycles during sharpening a magnet stayed fixed on the knife - the magnet had overcome the glue.

I don't know wether this indicates the extreme strength of the magnet, or the glue-resistance of Tufnol.

BugBear


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## wobblycogs (12 May 2010)

I've only set magnets like this once but I used a technique very similar to the one described by Bob. Drill a hole, sink a screw into it and sit the magnet on that. Getting the depth correct is important so that the door can be opened easily but doesn't fall open. Once the screw was at the right depth I roughed up the back of the magnet with a little sand paper and CA'ed it into place - there was no chance it was coming out again. I then stuck a piece of veneer over the top to hide the magnet before finally, I digging one of the magnets out again because I'd glued it in the wrong way round #-o


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## motownmartin (12 May 2010)

I have set magnets into box lids and the method I used was to drill a hole slightly smaller in diameter then press them in with a little glue, don't know what glue would be best though, I have used both super glue and Araldite, I would lean towards the Araldite.


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## Chems (12 May 2010)

2 Part Epoxy Araldite, used it on doors over 6 months ago and still holding well.


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## Tim Nott (12 May 2010)

I second araldite or similar - used it to glue litle magnets in recesses in push sticks so they can just be stuck on the side or front of the table saw.


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