I don't usually take many pics and when I do I delete after a while - here are a few that survived - EL84 PP parallel, output Tx, one of a pair.
I do not buy bobbins but when I need one I make it from fiberglass reinforced sheet (from AliExpress) design in Fusion360 and cut it on my CNC mill. I have 2 winders - homemade with stepper motor traverse, and an old 1950's Aumann made in Germany, this one can wind up to 1.4mm wire. Last photo is an adjustable bobbin holder I recently made, I'm sick of making a new one from wood with every new transformer I make.
I do not buy bobbins but when I need one I make it from fiberglass reinforced sheet (from AliExpress) design in Fusion360 and cut it on my CNC mill. I have 2 winders - homemade with stepper motor traverse, and an old 1950's Aumann made in Germany, this one can wind up to 1.4mm wire. Last photo is an adjustable bobbin holder I recently made, I'm sick of making a new one from wood with every new transformer I make.
Richard Hughes ("retailer" above) has some cool work, as seen in his posts over on vintage-radio.net
https://www.vintage-radio.net/forum/showthread.php?t=196485
https://www.vintage-radio.net/forum/showthread.php?p=1520135
Retailer , you may find more info here about the z565 -
https://audiokarma.org/forums/index.php?threads/rewinding-a-dynaco-z565-transformer.1019903/
https://www.vintage-radio.net/forum/showthread.php?t=196485
https://www.vintage-radio.net/forum/showthread.php?p=1520135
Retailer , you may find more info here about the z565 -
https://audiokarma.org/forums/index.php?threads/rewinding-a-dynaco-z565-transformer.1019903/
I did see the audiokarma 'dynaco - z565' thread about the rewind, pity there was no follow-up on how it turned out, there was some critical winding layout info missing, not all of the windings are in the same direction, if the op didn't notice this when the Tx was unwound to count the turns the end result would have been disappointing.
Nice work on the variable bobbin holders retailer and good work on the bobbin. A few questions, what are you using for interleaving insulation - Nomex? If so so what thickness. Also what thickness of FR4 are you using?
Andy.
Andy.
I've got 1.8mm thick glass reinforced board - it actually measures around 1.6mm - 1.7mm, came from Aliexpress - having made a few bobbins from it I feel I could go thinner and will get something around 1.2mm thick to use on smaller transformers. For interleaving insulation, when I use it, I have a mixture of various thickness of paper ranging from .02mm up to .08mm - I found some old rolls of lunch wrap paper dating back to the 1960's, thickness is around .04mm and a large roll of brown paper .06mm thick - one of the Avo Douglas coil winder user manuals (I can't recall which) has a small chart with suggested thicknesses of interleaving paper for various wire sizes. For insulation between windings, I have some insulation - not sure what it is called - came from a motor winder supply shop - comes in a 1.2m wide roll - 0.15mm thick.
Update-
Got sidetracked w/ resto of 2 tube receivers- Westinghouse 204 and RCA 7-BX-10 shortwave...
So after much thinking, decided B+ winding should be wrapped after primaries. They concluded w/ full bobbin row, so next group would have uniform platform to start. If had wound filaments instead- would have produced jagged landscape to wind the next 10 layers of 23ga- NFW
Pic 1 shows completed 10 rows of 72 B+ windings
Pic 2 shows how useful duct tape and a lawn chair can be when repurposed... add a six pack and you've got a 'sitter, but arranged differently- lmao
Pic 3 shows how much of the 625 feet 23ga I had left after winding the B+ (whew- knew it would be close)
NOW to filament windings- depth caliper indicates not much space left on bobbin relative to E cores...
To be continued...
Jim
Got sidetracked w/ resto of 2 tube receivers- Westinghouse 204 and RCA 7-BX-10 shortwave...
So after much thinking, decided B+ winding should be wrapped after primaries. They concluded w/ full bobbin row, so next group would have uniform platform to start. If had wound filaments instead- would have produced jagged landscape to wind the next 10 layers of 23ga- NFW
Pic 1 shows completed 10 rows of 72 B+ windings
Pic 2 shows how useful duct tape and a lawn chair can be when repurposed... add a six pack and you've got a 'sitter, but arranged differently- lmao
Pic 3 shows how much of the 625 feet 23ga I had left after winding the B+ (whew- knew it would be close)
NOW to filament windings- depth caliper indicates not much space left on bobbin relative to E cores...
To be continued...
Jim
Attachments
Finished the fix-
Pics below- Sequence of events...
1. Securing the connections
3. Measuring winding group- Measure 2.97" max point vs 2.99" space in laminates... whew, close again...
4. Fixed!! for what was ordered vs original label shown and what I received- caveat emptor-
Jim
Pics below- Sequence of events...
1. Securing the connections
3. Measuring winding group- Measure 2.97" max point vs 2.99" space in laminates... whew, close again...
4. Fixed!! for what was ordered vs original label shown and what I received- caveat emptor-
Jim
Attachments
this is my traffo diy page... https://www.diyaudio.com/community/threads/tonys-latest-traffo-diy-build.191730/page-53#post-7317549
Wow!
53 pages of 12 years of trafo builds-
I've only done 1- have new sense of appreciation for level of patience and determination 12 years takes. Impressive!
Jim
53 pages of 12 years of trafo builds-
I've only done 1- have new sense of appreciation for level of patience and determination 12 years takes. Impressive!
Jim
thanks, i have been doing transformers since 14, i am now 70, but i do it for fun, i am not a commercial winder and i do not sell transformers really...
Hi, I have posted in Software Tools section my new freeware tool for automatic bobbin design.
https://www.diyaudio.com/community/...ransformer-bobbin-design.400449/#post-7380628
@50AE, you may find it useful for your everyday work.
https://www.diyaudio.com/community/...ransformer-bobbin-design.400449/#post-7380628
@50AE, you may find it useful for your everyday work.
Attachments
Thanks, @LinuksGuru. It's a bit late for me to use is, as I've already done "all the drawings" I need, manually. I've got drawings mainly on double bobbin cut core amorphous and nanocrystalline AMCC series, and most HiB SU sizes.
@50AE , what kind of guide tooling you use to straighten 0.6 - 0.8mm wire and make trifilar winding? Some kind of plastic plate with rectangular canal? For monofilar winding I use set of custom 45deg V-groove rollers made from industrial nylon. It helps straighten thick enamel wires, albeit not perfectly for diameter 0.75mm+.
I saw this 6 V-groove roller wire straighten tool on youtube, yet it requires too high torque from spindle motor I don't have. My CNC linear coil winder is driven by 2 synchronized step motors from interrupt driven micro-controller as 2-channel pulse generator. Traditional scheme usually uses servo AC motor (which have much higher torque compared to step motor of similar size) for spindle with encoder to drive shuttle step motor. Replacing spindle motor with more powerful unit is quite difficult and time consuming in my case.
Thanks !
I saw this 6 V-groove roller wire straighten tool on youtube, yet it requires too high torque from spindle motor I don't have. My CNC linear coil winder is driven by 2 synchronized step motors from interrupt driven micro-controller as 2-channel pulse generator. Traditional scheme usually uses servo AC motor (which have much higher torque compared to step motor of similar size) for spindle with encoder to drive shuttle step motor. Replacing spindle motor with more powerful unit is quite difficult and time consuming in my case.
Thanks !
Attachments
Here's a pic of my wire guide, I've never wound a trifilar winding, I have done bifilar output transformer secondaries, each wire needs to be on a separate spool, but this for me is not common so I don't have a permanent setup for bifilar, I don't understand why you need to straighten wire if it is new wire coming off a spool, it is a well known fact that copper work hardens so bending it back and forth will actually tend to harden it. I have found this is not really noticeable on thinner wires up to 0.7mm - 0.8mm but with thicker wire say 1.2mm -1.4mm it is noticeable. My Aumann winder has a 500watt motor and can wind 1.4mm wire, even so I tend to go slowly with wire that thick. I feel you would only need a 6 groove wire straightener if you used secondhand wire that had kinks in it, a few times I've started a winding with 0.9mm wire and had to unwind after a few turns, a straightener would work well in this case.
I don't use second-hand used material. Enamel wire comes to retailer in huge spools, and then service man rewinds into small 3kg spools which perfectly fit into my stand spool holder with tensioner. As result wire has some kinks which is not a problem for thin wire, e.g. 0.4 - 0.5mm, but for 0.75mm+ my guide rollers are not enough to completely straighten it. Winding quality is still acceptable but I would be happy to remedy this problem.
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Ok now I understand, I have similar situation and have to wait a few days for it to be taken from large spools and put onto smaller spools, my supplier however does not put any kinks into the wire so no need to straighten. In addition to the old Aumann winder I also have a home made winder that I used for 7 or 8 yrs, the spindle drive uses a Renault 16 radiator fan motor, and the wire feeder uses a stepper motor taken from an old printer, the spindle it is not that powerful and maximum wire size I can use is about 0.7mm, here is a 1 min video of it winding a choke for a Fender Deluxe Reverb build.