ferrite machining?
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From: JW on 14 Jun 2010 08:04 On Sun, 13 Jun 2010 12:34:04 -0700 Archimedes' Lever <OneBigLever(a)InfiniteSeries.Org> wrote in Message id: <8jca161beuhe7o9tg96ernt5l757hcpc1e(a)4ax.com>: > Actually, a bobbin winder is the right tool. A lathe, even on its >slowest speed, is far to fast. ^^ *snicker* Looks like the shoe is on the other foot now. <i6pkv5hssuhpjbocljp35j6c7inb6gvak4(a)4ax.com> By your own definition, you are a stupid retard.
From: Archimedes' Lever on 14 Jun 2010 08:11 On Mon, 14 Jun 2010 08:04:12 -0400, JW <none(a)dev.null> wrote: >On Sun, 13 Jun 2010 12:34:04 -0700 Archimedes' Lever ><OneBigLever(a)InfiniteSeries.Org> wrote in Message id: ><8jca161beuhe7o9tg96ernt5l757hcpc1e(a)4ax.com>: > >> Actually, a bobbin winder is the right tool. A lathe, even on its >>slowest speed, is far to fast. > ^^ >*snicker* Retarded petard. > >Looks like the shoe is on the other foot now. Retarded attempt at a petard. ><i6pkv5hssuhpjbocljp35j6c7inb6gvak4(a)4ax.com> > >By your own definition, you are a stupid retard. You're an idiot.
From: JW on 14 Jun 2010 09:08 On Mon, 14 Jun 2010 05:11:22 -0700 Archimedes' Lever <OneBigLever(a)InfiniteSeries.Org> wrote in Message id: <g07c16h5jg7n17gnj6905ohbkpuas36rdu(a)4ax.com>: >On Mon, 14 Jun 2010 08:04:12 -0400, JW <none(a)dev.null> wrote: > >>On Sun, 13 Jun 2010 12:34:04 -0700 Archimedes' Lever >><OneBigLever(a)InfiniteSeries.Org> wrote in Message id: >><8jca161beuhe7o9tg96ernt5l757hcpc1e(a)4ax.com>: >> >>> Actually, a bobbin winder is the right tool. A lathe, even on its >>>slowest speed, is far to fast. >> ^^ >>*snicker* > > Retarded petard. >> >>Looks like the shoe is on the other foot now. > > Retarded attempt at a petard. > >><i6pkv5hssuhpjbocljp35j6c7inb6gvak4(a)4ax.com> >> >>By your own definition, you are a stupid retard. > > You're an idiot. No, but you are you according to your own definition in <i6pkv5hssuhpjbocljp35j6c7inb6gvak4(a)4ax.com> And retarded apparently.
From: JosephKK on 15 Jun 2010 07:28 On Sat, 12 Jun 2010 22:30:06 +1000, Grant <omg(a)grrr.id.au> wrote: >On Fri, 11 Jun 2010 20:20:54 -0700 (PDT), MooseFET <kensmith(a)rahul.net> wrote: > >>On Jun 12, 12:07 am, BlindBaby >><BlindMelonChit...(a)wellnevergetthatonethealbumcover.org> wrote: >>> On Fri, 11 Jun 2010 08:11:04 -0700, John Larkin >>> >>> >>> >>> <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: >>> >On Fri, 11 Jun 2010 06:41:57 -0700 (PDT), MooseFET >>> ><kensm...(a)rahul.net> wrote: >>> >>> >>On Jun 11, 8:42 pm, Yzordderrex <powersupply...(a)netzero.net> wrote: >>> >>> Does anyone know of ferrrite can be turned on a lathe? >>> >>> >>> I have a short 1" long by 1" dia. rod ( i know, i know, a personal >>> >>> problem) and I would like to have a grove machined into it to accept a >>> >>> few turns of wire. there will then be a bobbin slipped over that with >>> >>> the secondary on it. >>> >>> >>> I suppose this might be done with some type of grinder as well. >>> >>> >>> Just curious to know what machining options are available for ferrite. >>> >>> >>Grinding is the way to go. If you want to cut something that >>> >>you would normally do with a lathe in metal, consider a tool >>> >>post mounted grinder. Watch the temperature rise. >>> >>> >Maybe a dremel with a diamond wheel? >>> >>> >John >>> >>> After the grooves get ground (any cutting attempt will result in >>> fracture), you need to cover the rod with transformer tape to insulate it >>> from your primary wire. >>> >>> If you make an open ended core transformer, it will be pretty leaky >>> unless you use a closed loop core arrangement. >>> >>> You would probably be better off with a pot core. >>> >>> I would use a dremel tool and grinding or cutting (abrasive cutting) >>> disc attached. >>> >>> If you are making a large groove for a single layer of larger wire the >>> grooves will allow the wire profile to sit a bit lower., >>> >>> If you are using fairly small primary wire, you do not need the grooves >>> at all. >>> >>> Temperature rise? They are not magnets. There are no properties to >>> lose via introduction of heat. >> >>The one partedness can be lost through the heat rise at the machined >>point. They don't conduct heat well and neither does the grinder. >>I stand by my suggestion that temperature rise be watched. > >I just spent some time with a high speed hobby drill, various grinding >attachments and a then piece of ferrite, a figure eight buckle type they >wind those mains filters on, the type with sprocket teeth on the coil >former so the ferrite is one piece. > >Anyway, 150 grit diamond tool rips into the stuff, black dust everywhere, >easy to fracture pieces off, very harsh if one applies too much pressure. > >The sanders and other grinders a bit more gentle, most gentle (but slow) >was the thin cutoff wheel when use with light pressure and kept moving >to avoid localised heating. If I tried too hard to grind one spot, the >ferrite would fracture from the hot spot, through several mm of ferrite. > >Machining ferrite is easy, with a little practice to develop a feel >for what is easy, and stuff that is dangerous in the sense of risking >fracturing the job. > >Diamond tools would need to be a lot finer than 150 grit to lessen the >impact and give a smoother finish -- easy to control with light pressure >and rips out the material quickly. > >Interesting stuff to play with. And try different tool speeds, the >abrasion rate doesn't necessarily go up with speed. Odd? > >Grant. Pretty much what i expected from my understanding of the materials. Thanks for running the experiments.
From: Clifford Heath on 15 Jun 2010 20:18
Grant wrote: > Actually the morning after I played with grinding ferrite, I noticed > black edge highlights on the small rare earth magnets on the fridge, > collected the fine dust, they did. So next time I try grinding ferrite > I'll try a decent magnet near the work. It won't pick up the abrasive particles though, so a vacuum is still a good idea. |