Twist in a jiffy! Tip for transformers-Use an electric drill #50w


Brian N7BKV
 

Building my 4th 50w  Amp.  Got a tip from a friend to use an electric drill to twist the bifilar and trifilars.
It really works!  I was afraid at first it would come out uneven. 
Put one end in a vice.  Chuck up the other end into an electric drill.  Pull moderate tension.  In ten seconds JOB DONE!
Neat and easy.  Laid them over the manual page and took this pic:



Quicker and easier than I thought it would be.

Now some of you are probably saying--That's what we ALWAYS do!  Where have you been?

Sorry, but I did not see this in the manual and I am a slow learner. But if this idea helps someone, I am happy.


Mitch - KY4LY
 

I've seen this done other places but wasn't sure if it would work with such thin wire.


Glenn Maclean
 

I built the 50 watt amp for my 40meter QCX +. I am a retired aircraft mechanic.  I used my aircraft safety wire pliers that are made specifically for twisting wire! They made the process easy and the twisted wire came out even! I like the fact that you can stop twisting the wire when it looks correct with good control!
Glenn WA7SPY


Colin Kaminski
 

Thank you Glenn, 

I still have my safety wire tool from my motorcycle racing days. I’ll try it next time. 

Colin - K6JTH 


Roelof Bakker
 

Hello Brian,

- Where have you been?

I have been using the same method for decades, though instead of an electric drill, I am using
a small elbow steam driven manual drill.

Regarding the discussion of removing the enamel insulation, the 'solder blob' method is hard
to beat. I have yet to come across enameled wire it won't work, besides some pre-WWII stuff,
which has been binned.

73,
Roelof


Donald S Brant Jr
 

I used safety wire pliers to twist my wires also, but instead of using the twister feature I just clamped it to the wire ends, let it hang and spun the tool itself.  I was concerned that pullng the twister knob would put too much stress on the wires.
It came out great.
73, Don N2VGU


Bryan Curl
 

I also used a drill motor. Slick, like trout.
Only question I had that manual didnt answer, how many turns per inch are best. The drill can quickly twist on more than is probably needed if not careful. 
--
regards,
Bryan, N0LUF


Peter Lascell
 

So for those of us who didn't keep their safety wire pliers from our military experience, we can use locking vise grips instead, and spin them from the adjustment knob as they hang on the wires.  Still waiting a few more days for my QDX to arrive and test the twist. 
Pete W4WWQ

On Tue, Jun 21, 2022 at 7:31 AM Donald S Brant Jr <dsbrantjr@...> wrote:
I used safety wire pliers to twist my wires also, but instead of using the twister feature I just clamped it to the wire ends, let it hang and spun the tool itself.  I was concerned that pullng the twister knob would put too much stress on the wires.
It came out great.
73, Don N2VGU



--
Pete Lascell
Forest, VA


Brian N7BKV
 

Yes.  Over twisting was a concern.  But with adequate tension it all evened out in seconds.  As for twists per inch, yes, the manual says nothing.  So I just went by the picture with the finished wire next to the tape measure and made mine look about the same.

Brian N
N7BKV


Karl Haas
 

I’ve used this method before, and if it goes wrong, I tend to twist and shout.

 
Tuesday, June 21, 2022 3:15 PM +02:00 from Brian N7BKV via groups.io <cl@...>:
 

Yes.  Over twisting was a concern.  But with adequate tension it all evened out in seconds.  As for twists per inch, yes, the manual says nothing.  So I just went by the picture with the finished wire next to the tape measure and made mine look about the same.

Brian N
N7BKV

 
 
Karl 
 


Brian N7BKV
 

On Tue, Jun 21, 2022 at 06:20 AM, Karl Haas wrote:
I tend to twist and shout.
Right, Karl!  Came out so good it made me twist and shout!


Karl Haas
 

Very tidy job!  I just hope the bird doesn’t want its feet back!

 
Tuesday, June 21, 2022 4:27 PM +02:00 from Brian N7BKV via groups.io <cl@...>:
 
On Tue, Jun 21, 2022 at 06:20 AM, Karl Haas wrote:
I tend to twist and shout.
Right, Karl!  Came out so good it made me twist and shout!

 
 
Karl 
 


ajparent1/kb1gmx
 

Had to figure out that for my self.... nearly 50 years ago.
I had assumed I was the slow one.  ;-)

Note: for #28 wire at 8 twists per inch is roughly a 50 ohm
transmission line for a pair, same for trifilar.  One day when
bored I measured it.  Changes with several parameters, number
of twists (some variation from 4 -10), wire diameter, and insulation
thickness.

Biggest thing doing that is I do far more than needed and save it
in a mint tin for when I need a transformer fast

SUPER HINT:  use three different colors of enamel wire
Or paint them using Black, green, and red sharpie.  Saves
the process of identifying which end is which.

Allison
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ajparent1/kb1gmx
 

As someone that was involved with racing and aircraft ownership
I still have my safety wire pliers.  Also a small hand cranked
manual drill.

FYI: two many twists tends to make the wires brittle and I found
around 8 twists is easy to work with.  Two few makes it loose and
looks poor once on the core.  The majik number has a wide
variation as I did it as parallel pairs and triples.  That looks
pretty when using tricolor wire and buys nothing.  So there is a 
fair amount of latitude.   Also wide variations tends to only show
at increasing frequencies (greater than 20mhz).


Allison
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Jim Strohm
 

I like Allison's answer best.

Constructing the toroidal inductors as transmission-line transformers (cf. Jerry Sevick (SK)) makes them somewhat more efficient, assuming the circuit is designed for certain input and output impedances.  

Of course, twisting the windings makes adding or removing turns on one winding much more difficult, and compressing or expanding the windings on the core almost impossible.   However, the descriptions of the various woes suggest that the bigger problem is getting enamel off the wires, not the impedance of the completed inductor / transformer.

Sevick's writings tend to support this,

73
Jim N6OTQ 

On Tue, Jun 21, 2022 at 11:08 AM ajparent1/KB1GMX <kb1gmx@...> wrote:
As someone that was involved with racing and aircraft ownership
I still have my safety wire pliers.  Also a small hand cranked
manual drill.

FYI: two many twists tends to make the wires brittle and I found
around 8 twists is easy to work with.  Two few makes it loose and
looks poor once on the core.  The majik number has a wide
variation as I did it as parallel pairs and triples.  That looks
pretty when using tricolor wire and buys nothing.  So there is a 
fair amount of latitude.   Also wide variations tends to only show
at increasing frequencies (greater than 20mhz).


Allison
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