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noneyabussiness Guru Joined: 31/07/2017 Location: AustraliaPosts: 513
Posted: 07:05pm 22 Nov 2017
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Morning Aaron,
Alu wire you need about double the cross section to carry the same amps than copper... I think it works !!
Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 08:03pm 22 Nov 2017
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Aaron I have bought wire from motor rewinders before. They even let take the roll home and bring back what I did not use and they credited me for the unused wire.There are only 10 types of people in the world: those who understand binary, and those who don't.
Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406
Posted: 09:13pm 22 Nov 2017
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Aluminium wire is going to get mighty hot and reduce the power capability to about half of what it could have been if copper had been used. Even if its free, aluminium wire best avoided for what we are doing.
Edited by Warpspeed 2017-11-24Cheers, Tony.
Tinker Guru Joined: 07/11/2007 Location: AustraliaPosts: 1904
Posted: 11:01am 23 Nov 2017
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Beside that, it would be problematic to solder a connection lug to the ends. The commercial users use some fancy crimp terminals I would imagine.Klaus
Revlac Guru Joined: 31/12/2016 Location: AustraliaPosts: 1026
Posted: 11:50am 23 Nov 2017
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OK point taken Thanks. Will stick with copper then. I have half the c core apart now, they are marked so they fit back together the same way (polished ends) without any damage.
Cheers AaronCheers Aaron Off The Grid
Revlac Guru Joined: 31/12/2016 Location: AustraliaPosts: 1026
Posted: 11:57am 11 Jan 2018
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Starting to rewind this thing.
Using the wire I have 2X4mm actually measures about 2.5x5mm so I cannot wind on 45 turns per layer, the best i could manage was 39 turns.
would end up with 5 layers per side for the secondaries (she's gonna get tight with the primaries on) instead of 4 layers.
for 39 turns evenly it would be 390 turns total giving me .88 tesla for 38 turns per layer 380 turns total would be .91 tesla
So I think that 38 turns per layer will be the way to go.
Just a thought, some large heat shrink tube over each layer would help hold it all tight and insulate as well.
cheers Aaron Cheers Aaron Off The Grid
Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406
Posted: 06:06pm 11 Jan 2018
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Looking good there Aaron.Cheers, Tony.
Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 08:04pm 11 Jan 2018
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That's a neat winding job, where did you end up getting the wire?There are only 10 types of people in the world: those who understand binary, and those who don't.
Revlac Guru Joined: 31/12/2016 Location: AustraliaPosts: 1026
Posted: 09:53pm 11 Jan 2018
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Thats the wire that was on it, will be adding more to it. I found some more wire in the shed. keeping the primaries(15mm X 2mm) neat will be a challenge.
Cheers AaronEdited by Revlac 2018-01-13Cheers Aaron Off The Grid
Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 10:34pm 11 Jan 2018
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Appearances really don't matter so much, however neat means you are making the most of the available space.
How many turns and how much space is there for the primary?There are only 10 types of people in the world: those who understand binary, and those who don't.
Tinker Guru Joined: 07/11/2007 Location: AustraliaPosts: 1904
Posted: 09:28am 12 Jan 2018
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There might be a practical problem with your heat shrink tube idea. How will you get it on? With that kind of wire the tension has to be kept on the end or it will spring back. So you can't remove a partial wound coil from your former to slide the tube on.
What I would suggest is to wind one layer and epoxy the turns solid, perhaps wrap some mylar tape around as well, then continue with the next layer.
If it was me doing that I'd wind it in my lathe but perhaps you don't have one. If you do, make a slotted wooden or plastic friction clamp to fit the tool post, this keeps the wire taught. I use the thread feed screw to advance the tool post, the pitch of the wire usually comes close to a thread ratio. Small adjustments can be done by the compound slide.
And I turn the chuck by hand, much more controllable than even the slowest motor speed. Have fun.Klaus
Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406
Posted: 11:07am 12 Jan 2018
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I do pretty much the same thing on my lathe. Put it in a very low gear and turn the lathe motor by hand. It keeps the tension on, and if you stop, the whole thing does not unwind.
I also now have a turns counter, which can be handy if it becomes necessary to go back and remove a few turns, then go forwards again. Its quite easy to lose track of the exact turns count when trying to solve various problems, and possibly have distractions.Cheers, Tony.
Revlac Guru Joined: 31/12/2016 Location: AustraliaPosts: 1026
Posted: 12:59pm 12 Jan 2018
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For the primaries I would be looking at 44 turns total 22 each side and 2 in hand 11 turns per layer, that would be 4 layers of 15mm X 2mm.
But i should test it with a small wire rapped around and see if there needs to be more or less turns before the rest goes on.
As for the heat shrink idea, I can take off the plywood end and just slide the shrink tube on, same with the other end depending on were the next layer starts. Beforehand they just used tape to keep the end winding in place, epoxy is a good option, originally it was soaked in enamel and that worked ok to.
Winding using the lath was my first thought, Have 2 Lathes here and they are out in the yard, to hot and sunny ATM they should be in the shed but the 2 large sheds are full of other junk and no room to work, still do all the work in the yard as we haven't assembled the 42m x 12m shed that will sit between the other 2 sheds.
Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.
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