Basically you are going to paste the boards, then apply a UV cured adhesive to the first side, place the components and then cure the adhesive. Flip the board, paste, place, reflow.
The key is a UV cured epoxy. If you use a slower, heat cured epoxy you are defeating the purpose of the process.
Overall it will probably save a few minutes off of the reflow process time. The question is, is the capital for an additional machine, plus the floor space for the glue dot placement available. Remember, you are adding a machine to the line in the form of the glue placement. The UV cue oven may be a little smaller, depending on design so you could balance the floor space requirement there.
Kris Roberson
Manager of Assembly Technology
IPC
Kris Roberson has experience as a machine operator, machine and engineering technician and process engineer for companies including Motorola, and US Robotics. Kris is certified as an Master Instructor in IPC-7711 / 7721, IPC A-610 and IPC J-STD 001.
Side One:
Stencil Solder paste
Dispense Adhesive
Place Components
UV cure the adhesive
Flip the assembly
Side Two:
Stencil Solder paste
Place components
Reflow both sides simultaneously
The process saves the time of one reflow operation, but it adds the adhesive print and cure operation.
Edward Zamborsky
Regional Sales Manager
OK International Inc.
Ed Zamborsky is a Regional Sales & Technical Support Manager for Thermaltronics, located in New York. His position requires frequent customer visits throughout North America and the Caribbean and his position encompasses not only sales but the role of trainer and master applications engineer for all of Thermaltronics products. His expertise includes such specialties as hand soldering, convection and conduction reflow techniques, array rework, fluid dispensing equipment, and fume extraction. Ed has authored many articles and has presented many papers on topics such as; Low Volume SMT Assembly, Solder Fume Extraction, SMT Rework, BGA Rework, Lead-Free Hand Soldering, High Thermal Demand Hand Soldering, Lead Free Visual Inspection and Lead Free Array Rework.
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