Hi, I’m new to this forum. I’m making an optical device that relies on very small components. I’m trying to coat very thin soft iron rods or carbon steel rods that are ferromagnetic with white paint. The rods are less than 1.0 mm in diameter, and 1.75 mm in length. They need to be precisely dimensioned. When I try to use fine wire cutters, I can never get the desired length, and the paint chips off of them, making them useless. I need a precise manufacturing solution. I need to make several thousand of these tiny rods. Does anyone have any solutions, or could you direct me to a manufacturer who could produce them for me? Thanks for any input.
How are you currently painting them.
Perhaps powder coating them will produce repeatable dimensional results.
Also cutting them with some kind of saw vs a wire cutter may keep it from chipping.
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I’m assuming that you aren’t painting them after cutting, that they come painted, that you are trying to cut them to a precise length without damaging the paint already applied, and that you aren’t trying to paint the cut ends and bring the length to a precise value, but instead are trying to bring raw cut ends with painted outsides to a precise length.
You say “precisely dimensioned” but what are your tolerances? Since you are starting with wire cutters, it seems unlikely that you are looking for length to be correct within a thousandth of an inch.
What level of flatness do you need on the ends? Are the ends bearing surfaces?
If I were making these to ±0.1mm tolerance in length, I would be building a jig and using a saw. If I only needed dozens and flatness was not critical, I’d try a jeweler’s saw first, with a jig for blade guidance. If I needed more, or needed ±0.01mm tolerance, or needed a highly flat surface on the cut ends, I might set up a lathe to turn the rod while using a carbide saw in live tooling with a jig to set the length, hoping that this would avoid flaking the paint. A lot depends on the character of the paint! There can be a lot of variability here.
Depending on tolerance, I would also test making custom-sized shear cutters to see whether that could preserve the paint. A hole the right size drilled through two pieces of harder steel than the soft iron rods. There are a lot of design variables I might test to design them, but I’d start with a proof of concept for whether a shear cutter could avoid chipping the paint.
You could contact job shops for a quote, but be aware that the price will be based on the time it takes, not (say) for the size of the piece, and the time is controlled in large part by the tolerance you specify explicitly. This size is also watchmaker territory, which also would certainly not be cheap. 
You haven’t said where you are located. Availability of local job shops is highly variable depending on location.