The original “Mayer” rod. Popularized by Charles Mayer in the 1920's and still the most popular. Available in sizes #3 to #75 including many half sizes. The size refers to the wire diameter in mils (.001 inch). Wire wound rods can be stripped and rewound to save cost and reduce waste. There are no minimums and no setup charges for wire wound rods.

A formed (threaded, grooved, etc.) rod is roll formed from a solid steel bar and closely resembles a wire wound rod. The size of the groove determines the coating thickness the same way the cavity between wire winding does. However, the radius in the groove of a formed rod is less likely to clog and cleans up easier than its wire wound equivalent.

Commonly used to smooth previously metered coatings to paper, paperboard and plastic films. The coating thickness is governed by pressure (against a backer roll) or web tension. RDS smooth rods can be ground to meet any surface finish requirement and hard chrome plating can extend rod life significantly.

For higher viscosity coatings, gapped rods reduce clogging and eliminate lines. By winding a smaller wire with spacing (see image) the cavity created is wide and shallow allowing heavy coatings to flow better. A smaller wire creates a smaller interruption in the coating flow enabling the coating to wet out more completely. While a gapped rod is less durable than a double wound rod, it is also less expensive.

For higher viscosity coatings, double wound rods reduce clogging and eliminate lines. By winding a smaller wire on top of a larger one (see image) the cavity created is wide and shallow allowing heavy coatings to flow better. A smaller top wire creates a smaller interruption in the coating flow enabling the coating to wet out more completely. While a double wound rod is more expensive than a gapped rod, it is also more durable.

Most Common

Rod coating provides excellent accuracy and uniformity through a wide range of speeds at a low cost that is simple to setup and change over. Mayer rod coating has been and still is in the top three most popular coating methods.

Yes, rotating the rod will prevent uneven wear. Rotating the rod will also present a relatively clean rod surface to the substrate.

Normally the rod rotates against the web. However, rotating the rod with the web may result in a better finish for some coatings.

25 to 50 rpm is a good starting point. Rotate the rod faster to see if the coating finish improves.

Every application is different but most coaters operate with 5 to 15 degrees of wrap. The most flexible coaters will be able to adjust the wrap angle for different applications.

Yes, if the size change is significant enough to prevent the rod from laying flat on the rod bed. (Note that with a 60 degree V-groove rod bed, any increase in diameter will cause an equal increase in rod height).

The U-shaped groove of a formed rod cleans up easier than its wire wound counterpart. Unlike wire wound rods, the diameter of a formed rod increases very little from a small groove size to a larger one. Formed rods are generally less expensive at high volumes.

The cavity between wire windings is a V-shape while the formed rod has a U-shaped groove. Coating flows through the shapes differently so the actual transfer rate depends largely on coating rheology.

None, the coating thickness is determined by the wire (or groove) size.

Since rods are generally made of solid stainless steel, the rod diameter will have a drastic effect on rod price. The need for a rod holder depends upon rod diameter (and several other factors).

Use the size selection chart to find an appropriate starting point. Perform a test with that size (in the lab preferably) and measure the actual film thickness. Use the actual transfer rate (wire size to film thickness) to refine your size selection.

There is no minimum for wire wound rods. There is a 5 rod minimum per size for formed rods (or a $35 setup charge per size).

Our standard lead time is 1 to 2 weeks after receipt of order. We offer stocking programs for higher volume users. If you need an order sooner please contact us about expediting.

The most common cause is a high viscosity coating that will not wet-out. Add a surfactant to the coating or increase the time between coating and drying if possible. If not, consider an alternate rod type, such as gapped or double wound rod.

The rod is likely clogged with dried coating or some other contaminant. Make sure the coating is pumped through a fine enough filter. Rotating the rod also helps evacuate any particulates. The rod needs to be cleaned anytime coating has been allowed to dry on it.

The life of a coating rod depends on the abrasiveness of the coating and substrate, the hardness of the rod and how well it's maintained. Either the tops of the wires will wear down from abrasion or the grooves will clog up with coating. If the rods wear out consider chrome plating. If the rods clog up consider an alternate rod type. Check the pressure between the rod and the backer roll (if applicable).

Check the web tension across the rod (if applicable). Ensure that the rod is aligned with the backer roll (if applicable). Check the straightness of the coating rod and replace if bent.