coil winding issues

[hobbydude]

Hello,

I need to wind about 160 turns of 0.3mm copper wire around a short 5 cm ferrite rod.

I suspect that there will be too many turns in the coil to wind it in one layer, so I'll presume that I'll have to wind it in layers. But I was wondering how this should be done precisely; as I understand it, the windings should be in one direction, but I guess it is "not done" to start winding a coil, say, from left to right, and then, at a certain point, continue winding from right to left.

Is the solution to this problem that I should begin winding a first layer (for example from left to right) and at a certain point return to the beginning of the rod and start winding a second layer, also from left to right?

I thank you in advance for your help.

[oldrunner]

I think they have to be in the same direction but not sure.
http://chemelec.proboards40.com/inde...er=desc&page=1
is an electronics forum that I belong to and Gary the moderator has wound ferrite core coils before so you might join and post your question. I happen to be building a PI detector from his plans.

[hobbes_lives]

If 0.3 mm is the diameter of the wire, including the insulation, then 160 turns on a 5 cm rod will be one layer. Here's the calculation: 5 cm = 50 mm, so 50 / 0.3 = 166.67 turns.

[hobbes_lives]

As a follow up, depending on the application, the statement "the windings should be in one direction" likely means the direction around the core that you are turning the windings (clockwise vs. counter clockwise), not necessarily the left-to-right direction along the length of the core. In most applications, it is OK to start a new layer at the end point of the underlying layer and work your way back in the opposite direction along the length, so long as you are continuing to wrap the wire around the core in the same manner.

There are many different coil winding configurations that provide for different coil characteristics though, so knowing your application would help.