Glueing magnets
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I have an enclosure that has a polycarbonate front plate that removes completely for access. The primary method of holding that plate in place are 4 small but powerful magnets in the plate with 4 matching magnets let into the enclosure frame. I used good quality boat epoxy (for fiberglassing work) to hold them in place.
My problem is that the epoxy is not holding on to the magnets. I don't know if it is the operating temperature of possibly 60C (the two upper magnets in the polycarbonate loose adhesion), the fact that the magnets are really smooooth or what. All I know is that it's getting kinda old trying to remove epoxy out of the recesses, mixing up more epoxy, re-installing the magnets and waiting 24 hours for a full cure.
The bond of the epoxy to the polycarbonate plate is fine, it it always the bond of the epoxy to the magnet itself.Has anybody had similar issues and if so, what did you do to overcome the issue. Did roughing up the surface of the magnet help? I am afraid of scratching right through the thin (nickle?) plating. Did you use any special kind of epoxy/glue? How can I permanently install the magnets?
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@jens55 This isn't a direct answer to your question but what I did was use a couple of glass door hinges - the type that clamp the glass. Thus making the front panel a hinged door which gives full access but is somewhat easier than removing a panel and then finding somewhere to temporarily store it.
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@deckingman, thanks. I had deleted the post but since you replied I restored it so there wouldn't be an answer and no question.
What I ended up doing is to roughen the surface of the magnet with a file and the copper plating that is below the nickle did start to show. Rather than holding the magnets in my hand and likely getting some finger oil on the surface despite my best efforts, I stuck the magnets to the file and cleaned them (99% isopropyl) while they were stuck there. I cleaned the mounting holes, mixed up a batch of epoxy and put a single drop in each recess. I then, while leaving the magnets stuck to the file, put the magnet in each hole (hopefully the polarity is correct) and slid the magnet off the file. I figured I would give it one last go with being absolutely sure there was no accidental finger oil and having the surface roughened a bit.
Time will tell .....And to comment on your hinge idea - I had thought about hinging but decided that removal of the whole front was easier and also would likely have less air leakage (heated chamber). I have two handles on the outside so I just grab the handles, lift the front off and set it on the floor. Very simple, quick and no chance of accidentally ripping hinges off (I do stupid things on occasion)
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Well that was a big fat hairy fail with a cherry on top
The magnets stayed on for an impressive 4 opening/closing cycles .... -
You can get magnets with a hole in the center designed to fit flat head fasteners, so you can bolt the magnet in place.
Could that work for you?
Frederick
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@jens55 you may have to use magnets with holes in them so then can be fixed in place eg, pot magnets , or go for aa product like this but this may be to expensive https://www.masterbond.com/tds/supreme-3ht-80
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Yeah, I think I will order some holy magnets. Very annoying though - it's only two of the 8 magnets ....
