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dockrat
08-19-2011, 08:21 PM
I have this round plate epoxied to a magnet and would like to mig tack the upright to it as shown in the following picture. What effect would this have on the magnet or should I just drill, tap, and bolt it???

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1578Medium.jpg

Shuswap Pat
08-19-2011, 08:37 PM
Don't try to weld it. You will damage the magnet, and the magnetic field will cause grief with the welding - don't do it. Try a threaded connection.

Black_Moons
08-19-2011, 08:47 PM
Magnetic fields make welding VERY hard, they effectively 'blow' the arc out as the arc emits a huge magnetic field that gets moved by the magnet.

The heat will also destory some of the magnatism, you should of tacked it on before glueing the plate.

Recommend a bolt/nut, or removing the plate, tacking it on and reglueing it.

dockrat
08-19-2011, 08:54 PM
Thanks guys!!!! You have just comfirmed what I was thinking. No problem drilling and tapping as the magnet has a hole in the middle. Thats the route I will go.

Black_Moons
08-19-2011, 09:04 PM
Thanks guys!!!! You have just comfirmed what I was thinking. No problem drilling and tapping as the magnet has a hole in the middle. Thats the route I will go.

Btw, Depending on the application you know you may be able to make the magnet many times stronger by making a 'cup' for it?

(if its north on bottom and south on top for example)

http://www.vexplosion.com/Friendly_Magnets_files/Cup%20Magnet%20Close%20Face.png

Something like that, with a very small gap beween the magnet and the cup along the sides, but with the cup and magnet touching the metal to lift at the same time.

It completes the magnetic circuit, and can make magnets effectively many times stronger (although typicaly a smaller, more compact field, so bad for reaching objects further away)

flylo
08-19-2011, 10:15 PM
I bolted a HF welding ground magnet to the bottom of my 4 legged cane. It's made like the cup magnet & very strong, about 3"dia. It's amazing what it will pick up.

Paul Alciatore
08-20-2011, 03:22 AM
You will probably have trouble drilling and tapping magnets too. Perhaps a better solution for attaching these parts to each other would be a "jacket" formed from aluminum sheet with openings where the field will be used. Add some epoxy inside this jacket. It also provides the opportunity to add some mounting flanges to help mount the assembly. Plastics would work also.

dockrat
08-20-2011, 03:52 PM
You will probably have trouble drilling and tapping magnets too. Perhaps a better solution for attaching these parts to each other would be a "jacket" formed from aluminum sheet with openings where the field will be used. Add some epoxy inside this jacket. It also provides the opportunity to add some mounting flanges to help mount the assembly. Plastics would work also.

Paul, no problem drilling and tapping. Nice central hole in the magnet. Excuse the chitty picture

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1579Medium.jpg