If you are using individual washers in your process, there are several things to keep in mind:
The ID (inner diameter) of the washer will be the most critical dimension. It needs to fit over the pin. If your washers are flux-coated, be sure to allow for the added flux in your calculation.
Some IDs are too small for flux coating as the flux coating can easily obscure the ID and make it difficult to smoothly place a washer over a pin.
When you are flux coating your washers, less is more. In other words, 0.5% to 1.5% flux by weight is sufficient to reduce the surface oxides and prepare the surface for wetting.
Solder volume can be adjusted by adjusting the thickness. Contact us to help determine the best inner and outer dimensions for your application. Next we'll need to know the board thickness, hole size, and pin size. Then we can recommend the proper thickness for your washer.
Pin soldering to ensure a reliable solder joint on each pin can be challenging. Spacing, quantity, size, and location of the pins on a board, as well as the board thickness can make it difficult to get individual washers over the pins.
Manual placement includes hand-placing individual washers over each pin. This is viable for larger washers and simple pin design. However, as the pins get smaller, more complex, or larger in number, manual placement becomes more problematic.
The solution? InTEGRATED® Preforms.
InTEGRATED® Preforms are linked washers that can be cut to the configuration of the connector and placed in one simple motion, saving time and money.
Saves time - no need to place each washer individually.
Saves money - by eliminating the need for special pick and place equipment or extra fixtures.
InTEGRATED® Preforms are washers (or other shapes) that are linked together to allow for placement of multiple washers in one single motion. In virtually the same time it takes to place ten washers on one connector, by hand, one at a time, up to ten connectors can be ready for reflow.
InTEGRATED® Preforms washers are joined in a matrix by fine, precise strands of solder. These strands melt and flow to the adjacent pads during the reflow process, providing for a complete separation of the washer preforms.
InTEGRATED® Preforms require an even heating process - vapor phase and convection reflow are ideal. If the job is small enough a hot air gun will work, provided you apply the heat evenly.
InTEGRATED® Preforms are sold in single, patterned sheets. The pattern for each connector will be cut from the sheet. To determine the pattern, we need to know:
Hole size
Pin size
Board thickness
Alloy
Pitch of the pins (between the row and row-to-row)
InTEGRATED® Preforms are best suited for smaller volume applications that are not easily automated.
Tips for using InTEGRATED® Preforms:
Flux must be applied separately to both sides
Preforms must be flat in the application
Uniform reflow heat is required
Minimum thickness is 0.002" and maximum thickness is 0.018", but they can be stacked to achieve greater solder volume
Solder Tubes – Precise Solder for Connector and Wire Splice Applications
Indium Corporation’s Solder Tubes provide a precise, controlled amount of solder for heat shrink electrical joint termination within solder sleeves.
While Solder Tubes are similar in shape to standard washers, the tight wall-to-height/thickness ratios of 3 or more is a key distinguishing feature. Solder Tubes can be customized to meet your heat shrink solder sleeve requirements and are ideal for a number of applications including:
Radio systems
Wire harness
EMI shield to ground termination
Wire to wire splicing, and more
Flux Coating
Flux coating is available to facilitate the soldering process. Typically, flux coatings can be applied in the range of 0.5%–2% by weight and are available in no-clean, RMA, and RA. For more information, contact Tyler Hutchinson at thutchinson@indium.com or +1 315 853 4900 to learn more about flux technologies used with Solder Tubes.
Visual Reflow Indicators
There are two options available for visual verification that the reflow temperature for the solder has been reached:
Thermochromic indicator dye which disappears when the proper temperature has been reached. This dye is added to the flux coating and does not interfere with reflow.
External indicator ring which is made of an alloy that melts at a higher temperature than the base tube. Once the outer ring is reflowed, it is an indication that the base tube has also reflowed.
Features:
Wall-to-height/thickness ratios of 3 or more
Visual reflow verification
Flux coatings can be applied in the range of 0.5%-2% by weight
Available in the most frequently used solder alloys, including:
SAC alloys
SnAg
Sn63
Sn62
Sn10
Non-standard alloys are also available, depending on the alloy.
For more information, contact Tyler Hutchinson at thutchinson@indium.com or +1 315 853 4900.
