Author Topic: Trying to fabricate electromagnet, requesting help please  (Read 16825 times)

Offline burnit0017

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Hi, I am trying to fabricate a electromagnet. What is the recommended method for cutting the pocket for the coil to sit in? I tried a boring tool but destroyed the tool. 

Offline Bearcar1

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #1 on: July 19, 2014, 12:07:43 PM »
Hi Burnit', does the part have to be one piece? Consider making it in two or perhaps three separate pieces and silver solder them together. That is make the 'cup' for the magnet to nest in and then turn up a 'slug' to fit the center and secure with a screw from the back. Just an idea. otherwise trepanning a deep, narrow slot such as that will take some doing. Getting a cutter ground correctly is the trick.


BC1
Jim

Offline Admiral_dk

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #2 on: July 19, 2014, 12:13:06 PM »
You can get special tools for that - a special kind of boring bar that is curved and you might be able to grind a tool yourself that does not touch the object with anything but the cutting edge, but s normal boring bar will not do.

Offline sshire

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #3 on: July 19, 2014, 12:32:05 PM »
Agree that fabricating is easier and would save a lot of metal that would otherwise become chips.  You could also use an end mill a bit larger than the boring bar to create the starting hole and go from there. Once the pocket is bored out, the center post could be screwed in from the backside.
Best,
Stan

Offline burnit0017

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #4 on: July 19, 2014, 12:32:47 PM »
Hi, thanks for the help. Making it from multiple pieces seems like a great idea. Most of the time the obvious solutions eludes me. :facepalm:
I will give it a try and post results.  Working on large beam style engine to drive a permanent magnet alternator. Thanks again.

I have seen other projects with a small size electromagnet have 100's of pounds of pull force using only a couple of D cells. 

Offline burnit0017

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #5 on: July 19, 2014, 03:35:00 PM »



Boring coil pocket and funky DIY steady rest.

Offline smfr

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #6 on: July 19, 2014, 05:04:13 PM »
Another option would be to mill the slot on the rotary table.

Simon

Offline burnit0017

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #7 on: July 19, 2014, 05:14:05 PM »
Hi, thanks for info. Making it from two pieces will allow me to turn the coil on the center and then mount the center using a center bolt. It will be easier for me to fabricate. I used a old broken roughing mill end to do the boring, the method worked really well from me. Thank you for all the info.

Offline ths

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #8 on: July 19, 2014, 09:19:35 PM »
That really is a funky steady rest. Does it work OK? Hugh.

Offline burnit0017

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #9 on: July 19, 2014, 10:58:22 PM »
Hi, it helps and it does stop the work piece from flying across the room. If it starts to wobble, I stop immediately. It is a first attempt and needs improvement.

Offline burnit0017

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #10 on: July 20, 2014, 04:28:26 AM »







I still have to add coil.

Offline burnit0017

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #11 on: July 23, 2014, 02:50:21 AM »




Hi, Icompleted the fabrication. Thank you to everyone for the help.




Offline burnit0017

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #12 on: July 23, 2014, 06:30:30 PM »
<a href="http://www.youtube.com/watch?v=TDmv59p1XkA" target="_blank">http://www.youtube.com/watch?v=TDmv59p1XkA</a>


video showing results, fabricated a second EMag, wired two EMags is series, powered by 100 volt pulse from 7800 uF capacitor :zap:

Offline Bearcar1

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #13 on: July 23, 2014, 07:03:25 PM »
Looks like your EM's have a bit of oomph in them, what pray tell are you erecting them for if I could be nosey? It reminds me of the many maglocks I have installed on security doors. Quiet, efficient AND silent.


BC1
Jim

Offline burnit0017

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Re: Trying to fabricate electromagnet, requesting help please
« Reply #14 on: July 23, 2014, 07:26:42 PM »
Hi, I am working on a gravity assisted torque converter to drive a permanent magnet alternator to generate small scale electricity. Looking for a way to include positive feedback into the system. I may have to add a solar panel, 12 volt battery, and voltage multiplier circuit, to keep it running. It just a experiment at this point, but I can't stop thinking about. If I can't get it working after this, then I can move on.