Why is Wet Film and Dry Film Paint Measuring Crucial?

The lowly moist movie comb is a bit of used object within the paint world, however for 50p this easy gadget can prevent 1000’s in wasted paint supplies and hours of labour refurbishing tasks – why? Defined under.

Moist Movie Combs

Stainless Metal WFT Comb

The Stainless Metal Moist Movie Thickness Gauge is a hexagonal or rectangular precision measuring comb product of heavy stainless-steel. The high-grade stainless-steel is not going to be affected by acid or base components and are lengthy lasting, reusable and provided in a spread of thicknesses measuring as much as 10,000 μm (120 mils).

Moist Movie Thickness Gauges are designed to measure the thickness of coatings instantly after they’ve been utilized to a substrate. The gauge has a collection of notches minimize into its sides just like the tooth on a comb. The moist movie thickness of coatings together with paints, resins, lacquers, varnishes and gels and so forth might be measured.

Utilizing a Moist Movie Comb

Earlier than you begin, guarantee your Moist Movie Comb is clear and undamaged :

Place the gauge at a 90° angle to the coated substrate Make certain the gauge is in agency contact with the substrate. Take away the gauge in a straight line up. Assess the tooth of the gauge. The moist movie thickness lies between the biggest tooth that’s moist and the smallest tooth that isn’t moist. To make use of the comb on pipes, guarantee it’s positioned parallel to the longitudinal axis of the pipe. On tough surfaces, measurements will likely be constituted of the floor peaks and subsequently will signify the minimal moist movie thickness.

Aluminium WFT Comb

The punched aluminium combs supply the consumer a low price technique of measuring the moist movie thickness. Nonetheless, the aluminium combs usually are not as correct as precision shaped stainless-steel moist movie combs and has a shorter lifespan.

Plastic WFT Comb

The Plastic Moist Movie Combs are constituted of ABS plastic and are designed for use as soon as and stored as a report of moist movie thickness measurement for high quality assurance or buyer necessities. Metric and Imperial values are on the identical moist movie comb, 50 to 800µm on one aspect, 2 to 32 mils on the opposite.

Because the plastic materials is inclined to chemical & base components, these moist movie combs are strictly for one time use and must be both disposed off or stored as a report after use.

Moist Movie Wheels

The Moist Movie Wheel is a excessive precision, correct and simple to make use of instrument which consists of a set of three wheels. The central wheel is of a smaller diameter and is eccentric relative to the 2 outer wheels.

By rolling the gauge by way of a moist coating, the centre wheel ultimately touches the movie. This level on the dimensions signifies the thickness. When the quantity to solids ratio of the coating is understood (typically discovered on the product knowledge sheet provided by the producer), the moist movie thickness can be utilized to foretell the dry movie thickness.

A number of measurement ranges between 0 to 25µm and 0 to 1000µm (0 to 1 mil and 0 to 40 mils) can be found. The moist movie wheel is appropriate for each flat and curved surfaces.

So you have efficiently measured your paint however what about your dry paint?

Dry Movie Thickness Measurement

A dry movie thickness gauge is an instrument used to measure the coating thickness on both a metallic or non-metal substrate.

Dry Movie Thickness (DFT) is a vital variable that performs a task in product high quality, course of management and value management. Coatings are designed to carry out at optimum efficiency when utilized inside the specified vary as acknowledged by the producer.

DFT measurements can be utilized to judge a coating’s anticipated life, the product’s look & efficiency and guarantee compliance with contract specs or requirements.

Dry movie thickness might be measured utilizing two strategies :

1. Non-Damaging Thickness Measurement

‣ Strategies which don’t harm the coating or the substrate resembling magnetic, magnetic induction & eddy present.

2. Damaging Thickness Measurement

‣ Strategies which contain chopping the coating to the substrate utilizing a particular chopping instrument.

Mechanical Coating Thickness Gauge

The Mechanical Coating Thickness Gauge, generally known as the “Banana Gauge”, is a Kind I instrument designed for non-destructive measurement of non-magnetic coatings (paint, enamel, galvanizing, plating, and so forth) on metal.

It’s appropriate to be used in excessive threat areas resembling excessive temperature or flammable atmospheres, underwater or the place the danger of explosion is excessive and the usage of digital devices is mostly prohibited.

Digital Coating Thickness Gauge

Digital Coating Thickness Gauges use magnetic and eddy present ideas to measure coating thickness on each ferrous and non-ferrous metals, precisely and shortly.

DFT measurements might be carried out on both magnetic metal surfaces or non-magnetic metallic surfaces resembling stainless-steel or aluminium with the digital coating thickness gauge. The precept of electromagnetic induction is used for non-magnetic coatings on magnetic substrates resembling metal. The eddy present precept is used for non-conductive coatings on non-ferrous metals substrates.

Coating Thickness Gauge Calibration

Formal high quality methods, resembling these described in ISO 9001, require coating thickness gauges to be correctly managed, logged and calibrated. With a purpose to check the accuracy of a specific gauge, you will need to have traceable coating thickness requirements.

Calibration foils or shims are probably the most handy means of making a coating thickness commonplace on the substrate materials, floor end or kind. Shims present the perfect technique for adjusting the calibration of the coating thickness gauge to make sure the best potential accuracy.

Coating Thickness Requirements

As talked about above, most organisations require verification of gauge accuracy on the check web site every time a coating thickness gauge is put into service and at frequent intervals throughout use. There are three forms of coating thickness requirements generally accessible :

Licensed Coated Metallic Plates

Licensed Polystyrene Blocks

Licensed Plastic Shims

Licensed coating thickness requirements ought to have measured values that are traceable to a Nationwide Metrology Establishment resembling NIST or PTB and individually serialised for the traceability.

Licensed coated metallic plates & polystyrene blocks are perfect for verifying the accuracy & operation of coating thickness gauges and are an essential part in fulfilling each ISO & in-house high quality management necessities. They can be utilized to confirm the accuracy & operation of any Kind 1 (mechanical) and Kind 2 (digital) magnetic, eddy-current or ultrasonic coating thickness gauge.

Plastic Shims

Licensed Plastic Shims (foils) present a cost-effective & handy various to coated metallic plates, although they’ve a diminished accuracy of ±2 µm (±0.08 mil). A coating thickness gauge measures shim thickness when the shim is positioned over a clean metallic floor (i.e. zero plate). The certificates of calibration displaying the traceability must be included with every shim or set of shims.

Zero Plates

Zero Plates are superb to check a coating thickness gauge’s performance & calibration and when it might be troublesome or impractical to acquire an uncoated substrate.

Coated Metallic Requirements for magnetic & eddy present gauges normally embrace an uncoated zero plate. The primary gauge measurement is taken on the zero plate to confirm that the gauge measures zero accurately. If not, digital gauges can normally be adjusted to “0” on the zero plate. After this adjustment is carried out, the gauge ought to measure inside tolerance on the coated requirements.

It additionally offers a handy base onto which plastic shims & polystyrene blocks might be positioned for verification functions.

Verify zero, modify to “0” if needed, then place the shim/block on the zero plate and measure.

Ultrasonic Coating Thickness Gauge

Ultrasonic Coating Thickness Gauge measures coating thickness non-destructively over wooden, concrete, plastic, and so forth utilizing ultrasound expertise. To assist the ultrasonic sign penetrate the coating, a liquid couplant is utilized to the measurement space. The ultrasonic couplant (gel) is right for tough coatings and for vertical surfaces. Alternatively, a drop of water is usually enough for clean coatings on horizontal surfaces.

Place the probe on the coating and press all the way down to measure. The instrument sends a sonic pulse into the coating and listens for a mirrored image from the coating-substrate interface, displaying the thickness measurement on the show.

Damaging Coating Thickness Gauges

Paint Inspection Gauge (P.I.G.) / Tooke Gauge

A Paint Inspection Gauge is a testing instrument used to find out the general thickness, or the person layer thickness, of a dry paint or coating. A small incision is made by way of the coating all the way down to the substrate and the V-shaped groove is then noticed by way of a microscope on the gauge the place a graduated scale is used to measure the thicknesses of the coating layers, offered they’ve completely different colors. The width of the incision is then associated to the coating thickness. Please take be aware that the check is damaging to the coating and subsequently, it must be used with warning.

So now you know the way to take a moist movie and dry movie thickness studying for industrial paint purposes. In case you have any additional questions please use the Bio for more information.