Measuring a very fine wire with 10 µm precision

Hi,

My goal is to measure a very fine wire with 10 µm (or better) precision using the arduino. I've been looking around for a way to do this and I could not find anything other than laser micrometer. (i.e. http://www.micro-epsilon.com/optical-micrometer/micrometer/optoCONTROL_1200/index.html)

Is anyone familiar with a strategy/way to achieve this in a DIY fashion using the arduino. What kind of sensors would you need?

Thank you

Boots

It might help if you give an actual dimension for "very fine wire".

I'm guessing you are measuring the width of the wire. Is that true?

How frequently do you need to make the measurement?

one approach would be to use the wire to set the gap between two metal plates and measure the capacitance between them.

Boots507: My goal is to measure a very fine wire with 10 µm (or better) precision using the arduino.

Have you considered using a microscope?

Perhaps measure the resistance of a known length of wire, and correlate to cross-sectional area and thereby diameter.

johnwasser: It might help if you give an actual dimension for "very fine wire".

I'm guessing you are measuring the width of the wire. Is that true?

How frequently do you need to make the measurement?

Thanks for the reply.

I am talking about a wire of AWG44 around 0.0585 mm in diameter.

Yes, I am measuring the width/diameter of the wire and I would like to make the measurement several time per seconds using the Arduino.

PeterH:

Boots507: My goal is to measure a very fine wire with 10 µm (or better) precision using the arduino.

Have you considered using a microscope?

Thanks for the reply.

Yes, but I need to take the measurement automatically and several times per seconds.

dhenry: one approach would be to use the wire to set the gap between two metal plates and measure the capacitance between them.

Thanks for the reply.

I am not familiar with this approach. Would you have some examples or perhaps reading on that technique of wire diameter measurement.

Are you serious? You need to be able to distinguish .001mm precision?

What are you doing?

vasquo: Are you serious? You need to be able to distinguish .001mm precision?

What are you doing?

Hi,

10 micrometers = 0.01 millimeters AWG44 is finest wire gage I would like to be able to measure. I'm trying to read the diameter of the said wire as it unwinds from its spool.

I'm thinking 1micron... but still, 0.01mm resolution?

And what's your contraption/Arduino supposed to do when you detect a delta change of 0.01mm in the wire diameter?

I am interested in tightly spooling the wire on a coil former. The coil will then be used for another project and it has to be well packed. Instead of working form the theorical diameter of the wire when making the coil, I am interested in measuring it as it unwinds from it's original spool (more accurate).

Is anyone familiar with a strategy/way to achieve this in a DIY fashion using the arduino. What kind of sensors would you need?

The arduino and its limitations are fairly well understood. The sensor you seek will be the challange. kind of like wanting to use an arduino to turn an empty pizza box into a flat screen tv.

measure a very fine wire with 10 µm (or better) precision

But how accurate do you want it?

JimboZA:

measure a very fine wire with 10 µm (or better) precision

But how accurate do you want it?

I would be really happy if I could record the wire diameter within 0.001mm. I'm not sure if that is possible.

I am interested in tightly spooling the wire on a coil former. The coil will then be used for another project and it has to be well packed. Instead of working form the theorical diameter of the wire when making the coil, I am interested in measuring it as it unwinds from it's original spool (more accurate).

So you're trying to wind inductors? Are these audio inductors?

I'm just thinking, who cares about the EXACT diameter of your wire (and whatever 0.01mm variations it has)... it's more important to get the correct inductance and DCR (within % tolerance) of your limited equipment? .... rather than worrying about it's diameter?

Maybe build an inductance meter using an Arduino (very possible, with high accuracy) and have your machine keep winding until the set inductance value is reached -- regardless of your wire diameter variations.

This is a nice diagram explaining the difference between accuracy and precision

JimboZA: This is a nice diagram explaining the difference between accuracy and precision

Yes I understand. I would like to know if there is a technique that would maximize both accuracy and precision when dealing with a wire and target resolution of 0.001 mm.

Any thoughts?

If I wanted to wind a coil with maximum packing density (like for a Tesla coil secondary) I would just have the feed carriage lag a little behind so that the new wire is pressed lightly against the previous turn.

Boots507: Instead of working form the theorical diameter of the wire when making the coil, I am interested in measuring it as it unwinds from it's original spool (more accurate).

I'm skeptical that your measurement accuracy would be better than the manufacturing accuracy. Have you measured the actual thickness, and does it vary (between spools, or within a spool) by enough to matter?

If your goal is just to wind wire onto a coil former then I would have thought you effort would be better spent designing the winding mechanism so that the wire stacked itself correctly. Doesn't a conventional winder sort this out for you? I'm surprised that it's necessary to do anything with any great precision when feeding the wire on, or that there are any benefits in knowing the wire thickness precisely.

If you really do need to know the wire thickness as an academic exercise then I'd use a micrometer. If it's necessary to measure this repeatedly at different places along the wire then I'd pass it between a pair of fixed/floating rollers and use a micrometer to measure the position of the floating roller. But this still feels as if you're solving the wrong problem.