hey i got a rare earth magnet from radio shack the 1/8 " one-what size hole do i drill and how do you lock it in .My guess was to use a smaller drill bit and hand file it till it just barely fits in then use lock tite bearing and sleeve formula to secure it.I wanted to see what everyone thinks about doing it this way.The only problem i see is that the magnet is really thin-does anybody have a favorite way to do this? than x

Drill it exact size. Glue it in with thin CA. Then pein a couple times around it to lock it in.

If it's 1/8" use a 1/8" bit, drill a hole as deep as the magnet, (not counting the coned part), mix some JB weld, dab a little on the magnet making sure to get the sides. Now put it in the hole and tap it down until it's flush with the surface. Take a center punch and put four punches about 1/32" from the magnet, it won't come out. Make sure you have the polarity correct if you put it in the wrong way the sensor won't see it.

Flat drill, same diameter, press fit with epoxy, flexible ca, or JB Weld.

I agree with the peening also. It should fold the metal in hard against the magnet. Capt,n

thank you i now feel confident it will NOT come out in flight!!!

Soarrich,
Which way is proper orientation? attract or repel?

Obee

I must be very lucky. I've made probably 15 prop hubs and installed the magnet. I wouldn't have a clue how to tell polarity but they all ran. Terry at CH warned me to get the polarity right too, I was affered to ask how the heck do I do that.

Plug the ignition in, then run the magnet under the sensor while you're holding them, one way it will triger the ignition, the other way it won't. Mark the side toward the sensor so you remember, when installing the magnet in the prop drive the mark side should be out.

Generally they should attract.

All sides of a magnet will attract metal. Polarity becomes a concern when another magnet enters the picture. Then it becomes opposites attract, same repels.

its not the attraction or repulsion.. the word you are looking for is "polarity".
one side of hall effect sensors will be triggered by a consistant polarity; either south or north. Flip the magnet and it wont get triggered - but flip the sensor also, it will trigger again.