Seems like there isn’t really any other place for this one. I was wondering if anyone had any experience having custom inductors wound. I need toroids wound, 50 or so. They are pretty small, and the material is not usually stocked. So wonder if anyone had any experience with this kind of thing, and where to go. Of course price is very important too!!
Coilcraft can supply custom-wound toroids.
The setup cost for a small quantity like that might be excessive, however, so it might be best to do them yourself.
Leon
Greetings (No First Name Supplied),
Are these mains frequency (power transformers)? Or,snarfer:
I need toroids wound, 50 or so. They are pretty small, and the material is not usually stocked. So wonder if anyone had any experience with this kind of thing, and where to go. Of course price is very important too!!
ferrite cores?
Either way you need to find a winding shop that builds
transformers. Many have machines to wind toroids,
they also have sources for raw materials.
Look in an industrial directory (or search on-line).
As we don’t know where you are (or even what
continent you are on we can’t help further.)
Why do you require a custom inductor? Most coil
suppliers have a catalog of standard values and
sizes (much like resistors.)
Comments Welcome!
Neither mains frequency nor ferrite. They are MPP cores less than an inch in diameter, with a flux density that is pretty hard to find. I had to order them direct from the manufacturer because the only distributor with stock never even replied to my inquiries.
Believe me, if I could order parts that are normally stocked and still get this kind of performance and size I would do it in a second. I have done a lot of testing.
Actually I have been winding them myself, but I’d like to find some place that can put them in a proper holder so I could reflow them on the boards.
I am in Thailand so I could always just go find some of those guys that sit on the street rewinding motor armatures (yeah they have that here. I have never been able to figure out who they are working for.). But then they wouldn’t be in the nice holders and everything.
Also I would like to find a place that can make small numbers of custom high frequency ferrite transformers for a power supply project I’m working on. Sure, there are tons of places here that will wind EI transformers, but that’s all they know about. The ferrite cores and stuff are all really cheap to buy, but it’s surplus stuff from the local contract manufacturers and the people selling it don’t even really know what it is, let alone how to wind it.
Dealing with the Chinese or Taiwanese companies that do know their stuff is a nightmare, anything less than 500 or 1000 pieces and line goes dead.
And yes, as I said, if I could use standard values I would. It’s the difference between 89% efficiency and 95% efficiency.
Looking in an industrial directory or searching online doesn’t really give the whole story, the reason why I posted was to find out about the actual experiences of others.
Greetings (Still No First Name Supplied),
As you didn't *really give the whole story* in yoursnarfer:
Looking in an industrial directory or searching online doesn’t really give the whole story, the reason why I posted was to find out about the actual experiences of others.
OP its going to be hard for anyone to help.
As for actual experiences, I have obtained ferrite
cores and bobbins as samples (and purchased in
sub-100 pcs) from the stockists listed by the
manufacturuer. Many were not local but had USA
1-800 tollfree phones.
I started my search in the Thomas guide (pre-www
daze), but have done it on-line more recently.
I have also placed small run jobs for both coil-
over-core power line transformers and custom
ferrite transformers.
Coil winding is an art. I have a small winder that
I use for ferrite prototype coils and transformers.
Good luck with your project!
Do you gap ferrites yourself? If so how do you go about doing that?
Regards,
(Still obstinately failing to supply first name)
I’ve used a piece of paper before now for a prototype.
Leon