Home Contents Search Links

Electronics Potting

Return ]

 


Electronics Potting Epoxy

Technical Bulletin

 

Precision Epoxy Products
a division of : Rock Art, Ltd.
4279 Midway Drive
Douglasville, Georgia 30134
Phone : (770) 489-0340


    Product Description:  Electronics Potting Epoxies are used to cast, insulate and contain electronic circuitry within a container or mounting box. The idea is to encapsulate circuitry components, connection wiring and miscellaneous hardware to insulate, contain and protect. Our 100% solids potting/casting epoxies are non conductive and achieve all three objectives well beyond what your project may require. They also provide protection from exposure, thermal shock, vibration, moisture, vandalism and spying eyes. With the wide range of formulations available from Precision Epoxy, we can meet your needs regarding liquid or solid state properties to suit your application. The Rigid Casting Series Epoxies and the Deep Casting Series Epoxies are the most popular for potting applications. Potting epoxies are available in clear, opaque or can be pigmented to your choice of color ( see Color Chart). De-air additives can be apart of the potting epoxy formulation to allow for total air release without the need for torching to remove surface air bubbles. This factor along with very low curing  temperatures protect encapsulated circuitry from any thermal damage during the casting process. Our potting epoxies can handle extreme conditions once they are put into service. This includes extreme hot or cold temperatures, freeze / thaw cycles, impact resistance, chemical attack and submersion.

    Coverage:  When casting or electronics potting, you will be dealing with cubic volume, one gallon of epoxy mix will fill 231 cubic inches. For flat surface laminating, coverage will be as follows :

Description : Inch Depth : Square Feet per Gallon
Pour option 1 1/16 25.6
Pour option 2 1/8 12.8
Pour option 3 3/16 8.5
Pour option 4 1/4 6.4
Pour option 5 3/8 4.26
Pour option 6 1/2 3.2

    Surface Preparation:  Surfaces that are being bonded to should be clean, dusted and free of grease, oil, wax or silicone. A light blast of air into potting box will remove any unwanted debris prior to the epoxy pour. Potting epoxy can be poured in multiple layers as needed for circuitry placement situations or for very deep pours to avoid exotherming conditions or problems. There will be no delamination between pours and multiple pours will cure as one solid unit. Complete all wiring, circuitry placement and layout prior to final encapsulation pour.

    Shop set-up: A location for an epoxy mixing shop will need to be set-up and ready for use as apart of the potting procedure. The mixing shop should be as close to the work area as possible to stage and mix epoxies, to access application tools and to prepare and clean up as needed. A potting epoxy shop can easily be set-up as part of a regular work station. We provide epoxy products in 5 gallon, 1 gallon, quart and pint packaging options to suit your needs and volume requirements. Precision Epoxy also offers accessory kits with all the items to complete your potting shop. For smaller operations, we offer 400 ml and 800 ml beakers that are used for the entire process. The beakers are calibrated allowing for the measuring of both epoxy components at the proper mix ratio. Then with the special mixing blade attached to your drill, the components can be stirred at the recommended 2 to 4 minutes to mix properly. Once mixed, the beaker's 'No Drip' pouring collar allows epoxy to be poured into the potting box with extreme accuracy and zero mess. Should smaller detailed and/or tedious applications be needed, we offer a calibrated 12 cc syringe type liquid transfer pipette. The plastic tip is cut off as desired to establish the size of the flow hole. Then the epoxy can be applied as a single drop or inject as much epoxy as needed with pin point accuracy. Add a mix blade rest and drip pan, an optional infrared thermometer, an optional candle warmer hot plate (used with beakers to bring epoxy resin Part 'A' to a controlled temperature) and your epoxy mixing shop is complete. For larger operations, we can package as needed up to 55 gallon drums to suit the needs of automated measuring and dispensing equipment found in assemble line type operations. Precision Epoxy can assist in every detail from start to finish to help with your complete electronics potting operation no matter how big or small.

    Measure:  Follow mix ratio as described on product's label. The mix ratio will be by volume and it cannot be over emphasized that proper mix ratio be strictly adhered to. Do Not alter the mix ratio for any reason. Should measuring of components be done by weight instead of volume, contact Precision Epoxy for the component weights of the product you are using. Calibrated measuring units of various sizes are available from Precision Epoxy.

    Mixing:  Mix the measured Parts 'A' and 'B' components in a clean, dry container. Components can be stirred until material is thoroughly blended using a flat stir stick for 6 minutes. This is a primitive method and is not recommended for normal applications. Material should be blended with an electric drill motor and the appropriate size mixing blade for 2 to 4 minutes depending on your batch size. Proper mixing blades are available from Precision Epoxy. If material is not mixed thoroughly, final pour could have soft or sticky spots or a marbling appearance on the surface. Be sure and scrape sides and bottom of mixing container to include all of both components into the blend. Avoid whipping air into material while mixing.

    Pouring:  Pour material into prepared potting box or mold in such a fashion as to aid in leveling if possible. The potting epoxy will flow on it's own and fill in around circuitry and/or hardware in most applications. Epoxy can be moved around, if needed, with an appropriate size spatula to help with even distribution. Potting box can also be rotated and/or gently pitched from side to side to move epoxy around to coat all circuitry as needed. A dust cover is advisable if a perfect finish is desired to keep dust or flying insects from ending up cured into the top surface.

    Torching:  Allow completed pour to sit several minutes to allow epoxy to migrate into all the nooks and crannies of the circuitry layout. As the epoxy fills in, it will push air bubbles out that will float to the surface. With a standard propane torch, wave the blue flame like a wand slightly above the epoxy pour to break the surface tension and release air bubbles that have migrated to the surface but have not yet released. Do not hold the torch in one spot to long, keep it moving with even strokes. The epoxy is not flammable, however; should flame touch the epoxy surface it can leave a discolored or sooty mark. Should this happen, simply dip out the burn mark with your spreading tool and continue. Any bugs or debris that might find their way into your pour can also be dipped out in the same manner within your 'Open Time' window and the epoxy will self level back smooth again. Air bubbles are also created when measuring components, mixing components, pouring mixed epoxy and from elements created by the surface you are pouring onto. Minimizing the sources of air will help with clear coat pours, however, clear coat pours will always need torching. If you are pouring with a pigmented epoxy color system or opaque system, the epoxy can be formulated with de-air additives that will allow all entrained air to release on its own and eliminate the need for torching.

    Final:  There will be a point that you will have to 'Leave It Alone' and let it cure. If flaws exist the next day, simply cut, grind or sand them out and re-pour. Allow epoxy to cure the appropriate amount of time as indicated on the product's label before handling. Curing times can be accelerated by raising the ambient temperature around the pour if needed.


The following are our standard Epoxy Products suitable for Electronics Potting.
We also offer Modified Versions and Custom Formulations.

All mix ratios are by volume.

  •   Rigid Casting Epoxy Series  is a fluid system used for structural bonding, laminating, art casting, electronics potting, etc. The RC Series epoxies are selected to suit the application environment and temperature. They are available in thick or thin viscosity versions to suit a wide range of applications and rates of cure. These systems are non-conductive, high strength, high heat distortion, self-leveling epoxies and are available in clear, opaque or pigmented versions.

  •   RC-52  (mix ratio 1:1 / A:B)
    Rigid Casting Epoxy - 52 is the 'Fast Cure' of the series for specialized applications. This system has a pot life of ten minutes and reaches handling strength in one hour at 77 degrees F.

  •   RC-53  (mix ratio 2:1 / A:B)
    Rigid Casting Epoxy - 53 is for use in applications requiring a rapid cure or for use at lower application temperatures. This system has high strength properties without being brittle, making it ideal for specialized casting.

  •   RC-55  (mix ratio 1:1 / A:B)
    Rigid Casting Epoxy - 55
    is the most widely used of the RC series. The 45 minute pot life at 75 degrees F seems to make it suitable for a wide range of applications.

  •   RC-57  (mix ratio 2:1 / A:B)
    Rigid Casting Epoxy - 57 has the slowest rate of cure for use at higher application temperatures or tedious applications where more open time would be useful.

  •   RC-190  (mix ratio 2:1 / A:B)
    Rigid Casting Epoxy - 190 is a special 'Armor Plating' formulation to satisfy special needs of the electronics potting industry. This system is extremely hard and durable making it virtually impossible to be broken down to reveal circuitry within the casting. Available in a thick black color to further hide contents within the casting.


  •   Deep Casting Epoxy Series  parallel the Rigid Casting Series Epoxies. The DC Series epoxies contain a filler to eliminate 'Boiling' in large deep (3/4" plus) pours and are selected to suit the application environment and temperature. They are available in thick or thin viscosity versions to suit a wide range of applications and rates of cure. These systems are non-conductive, high strength, high heat distortion, self-leveling epoxies and are available in opaque or pigmented versions.

  •   DC-52  (mix ratio 1:1 / A:B)
    Deep Casting Epoxy - 52 is the 'Fast Cure' of the series for specialized applications. This system has a pot life of ten minutes and reaches handling strength in one hour at 77 degrees F.

  •   DC-53  (mix ratio 2:1 / A:B)
    Deep Casting Epoxy - 53 is for use in applications requiring a rapid cure or for use at lower application temperatures. This system has high strength properties without being brittle making it ideal for specialized casting.

  •   DC-55  (mix ratio 1:1 / A:B)
    Deep Casting Epoxy - 55
    is the most widely used of the DC series. The 45 minute pot life at 75 degrees F seems to make it suitable for a wide range of applications.

  •   DC-57  (mix ratio 2:1 / A:B)
    Deep Casting Epoxy - 57 has the slowest rate of cure for use at higher application temperatures or tedious applications where more open time would be useful.



Back Home Return Next

Return ]

Copyright 1970 - 2014 / Rock Art, Ltd.

Precision Epoxy Products
4279 Midway Drive
Douglasville, Georgia 30134
(770) 489-0340

Notice: All Photographs and Text in this web-site are Copyrighted and are the sole possession of Rock Art, Ltd.
Any unauthorized use is strictly prohibited by law. Violations will be treated appropriately.

Hit Counter