Re: Of Partridges and Other Fashions Re: Is the Williamson still a good amplifier to build?



Happy winding,

You can see in this thread precisely why I read a few books on winding
transformers, then decided to do the job right. Doing it right means
one of two things:

1. Finding out who is the best commercial winder in the world -- bound
to be a supplier to the broadcast trades, with supply to the guitar
trades coming a very close second -- and adapting your circuits to
suit his off-the-shelf transformers. The best commercial winder in the
world if you aren't counting pennies is widely agreed to be Lundahl.
If you're counting pennies, you can't beat the guitar amp tranny
winder Hammond.

But what broadcaster buys large enough quantities of OPT to justify
constant productions?

But yes, Lundahl are very nice, and Hammond so-so to also very nice
depending
on exactly what you buy.

2. Finding out who is the best designer in the world and let him
design his heart out to achieve he precise effect you want. This is,
again by the widest possible acclaim, Menno van der Veen. I have no
idea whether Menno will design one-offs for the punter walking in off
the street; the work he did for me had clear commercial possiblities
and the transformers he designed for me later went into production.
However, Sowter will adapt one of the many sound transformers in their
list to your custom purposes and they are not very expensive. Or
Patrick Turner or Lucas Cant will design and wind a transformer for
you from scratch for pretty much starvation wages (it will still be
pricey compared to Lundahl), which might be very attractive if you
live in Australia and don't have to consider carriage.

Lucas has specialized in SE OPTs I think.

I do not wind transformers commercially or else I would me sent mad
being a transformer winder only.

Most enquiries I get do not come with an offer no more than peanuts for
payment.

I rarely sell a transformer which isn't surrounded with the rest of the
amp its meant for.

But I have supplied the world with a decent list of steps to take to
design their own superlative
OPT, and I get constant emails from ppl who have tried themselves.


Unless you already have a tranny you can strip down for parts, or can
buy a kit of parts (expensive in RS, and you have to take what is
offered, just about zero choice), it will probably cost more to DIY a
pair of trannies or a singleton than to get one custom designed and
built by people who can take the parts off the shelf.

It depends how one prices one's own labour.

A diy person who works in a daytime job day and winds trannies instead
of watching TV at night
won't value his labour at all.

The cost of wire is about $US 12.00 per kg, and laminations are also
about $14.00.
A 4.5Kg trannie has costs including bobbin and bolts of about $20 per
kg, so $90 all up.

A maker like Hammond us tonnes of wire and iron, and pay only 33% of the
above figures.

Work backwards from the retail price and things become clear.

The DIYer hates paying anything of course for his hobby of avoiding
costs
and forcing mediocrity to look like class.

His wife screams for a car or a new kitchen worth thousands, and
he soon arranges a loan extension to pay for it.

people are very inconsistent when they are into hobby work.

So I won't work for such hobbyists who'd like me to work for shit.

I'll tell em what to do though.



3. There is a possibly less expensive but much dicier alternative. Buy
a custom or standard design from a recognized designer, or make your
own design, and take it to the local armature rewinders. There's one
in any medium-sized town, or the next town along; try the yellow
pages. They have all the necessary parts on the shelf, or at most a
week away from regular suppliers who won't even take your call.

I have to disagree that there are any winders of any darn thing who
welcome a visit from a
guy with a diagram of how to wind an OPT.

Sure there are motor re-winders here, and NONE have a lathe to wind
transformers.
Armatures and stators are only re-wound when its economically viable,
ie,
there is no cheap Chinese replacement for big electric motor.
I've watched the boys laying wire turn by turn onto an armature or
stator.
Its skilled, and costly handwork, but the motor might be worth several
grand, so worth the re-wind.
Its also mainstream, and not hobbyist, and companies pay real money to
keep
the wheels of industry turning.


Or
local commercial transformer winders, perhaps to the marine trade, may
be set up to take an order for a pair of trannies.

All the winders of transformers in Oz hated me calling them and asking
for a quote.

It meant they had to do things MY WAY, not theirs, and I had to
painfully point out to them
that I had already wound lotsa gear myself, and their methods sucked,
and please, do it the way I have
specified please.

Then they'd take 6 weeks to reply to emails, and charge a silly price.

A few things became clear. Gross incompetence is a feature of
transformer winders of Oz
because those in the trade only ever wind easy mains trannies.
They cannot handle anything slightly complex or gurrantee their work,
and they have no appetite for a challenge.
If I were to engage anyone in Oz, I'd wait years and go broke.
Not one winder understands bandwidth, or saturation effects.



A chap called Russ
who came to RAT for years had his own design of trannies wound by
winders he picked out of the phone book, with great satisfaction
according to his reports, and at a price not too much over what Sowter
charges IIRC. It is worth repeating that you must have a complete
design and instructions ready to go or you will be hit with hourly
charges that will pop your eyes. This method saves expensive carriage
but if you get it wrong, all your money is wasted and you will wish
you had gone to known-good specialists with their own established tube-
knowledge.

You are the eternal optimist Andre.

My answer to the OPT and PT and choke problem of no good commercial
local availablity
anywhere within Australia was to build a winding lathe myself and design
and wind all my own
after and during the process of learning and practicing winding things.

My lathe is primitive, and with no auto traverse feature, but I get the
job done.
Despite taking 4 times the time a tradesman takes in a factory doing it
all the time,
its still viable for me to do it.

The last couple of guys left who might occasionally wind something in
Sydney, and known to all the
amplifier builders there have just retired. They get old, and
can't/won't do it any more.
Some started as starry eyed apprentices in 1957, when there were sizable
factories in Oz making
transformers for 1,001 users before we had access to the Chinese crap.
I know a guy who has bought a beautiful old German made lathe from a
retiring tradesman that allows him to wind anything
including perfect layer wound step up trannies for ESL speakers using
really fine wire.
He isn't interested in winding anything for anyone commercially, unless
its a repair for an expensive
ESL speaker. He also has a day job because audio work always pays
peanuts.

Patrick Turner.
.

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