By Joe Tito Wiring Harness News ______________________________
If you ’ ve been reading our Industry Profiles , the history of Baltimore based RESCO Electronics may sound a bit familiar . Their story was recently told by David Copenhaver , President of RESCO .
The company was founded in 1932 by John Bagliani , Sr . as Radio Electric Service Company of Baltimore . Radio Electric ’ s original business was selling vacuum tubes and other electronic parts to radio repairmen . The counter sales operation eventually expanded to sell parts for TV repair as well , and grew modestly until John Sr .’ s sudden passing in 1956 . With two sons not yet in the business , John ’ s wife Edith
Testing Appliance Cables & Connectors had no choice but to take the reins . By the late 1950 ’ s , Edith and her sons , by then working for the company , realized that long-term growth could not be sustained by selling to radio and TV repairmen and began selling electronic components directly to OEMs . In 1978 , Edith decided it was time to retire and turned the business over to her son , John Jr .
John had always shared his parent ’ s commitment to growing the business . When presented with an opportunity from one of their customers to do some value-added assembly in 1990 , he jumped at the chance . Overall , the distribution business had a heavy emphasis on electrical connectors which made it easy to segue into assembly work . Harnesses and
Driven by the desire for higher capacity appliances within the same external design envelope , and by the more complex functions , electrical design is being steered towards more and more compact solutions – solutions that include combining signal and power lines within a single connector , and reducing the pitch of board connectors .
Consequently , micro-pitch connectors are seeing greater use in appliance board-to-board and board-tocable interfaces and with narrower pitch comes a higher probability of shorts .
Smaller gauge wires are more difficult to insert , and combined with well-documented contact locking lance issues there is greater chance of continuity breaks especially when Connector and Terminal Position Assurance devices are neither features of the design nor of the chosen connector .
Additionally , some high performance high-density board-to-board connectors incorporate a ‘ floating ’ design that mechanically absorbs alignment errors thereby reducing stress & solder cracking . These floating contact systems can move in two lateral axes by as much as ± 0.6 mm . During the operation and life of the appliance , there is a probability that this floating contact may move . How can continuity be verified across the full range of available motion ?
Testing continuity & HiPot using multiconductor cable testers is an essential part of the workflow . Thorough testing prior to and after instal-
_____________ Continued on page 43
Advanced electronic assemblies at RESCO , Acuña facility .
The following is an adaptation of the presentation titled Laser Wire Stripping Masterclass that was given by Dr . Paul Taylor , Founder of Laser Wire Solutions , at the EWPT Expo 2018 . The class covered the history , applications and safety protocols for lasers used to strip wire . Special thanks for Dr . Taylor for helping prepare this adaptation , and also to Robert Tito for taking copious notes during the presentation .
Laser wire stripping has been around for 50 years , yet it remains somewhat of a niche . The first CO2 lasers were developed in 1960 and it didn ’ t take long for IBM to adapt them for wire stripping . The technology was pushed by NASA for use in the Space Shuttle Program in the 1970 ’ s and 80 ’ s . The Richard T . Miller Company began to bring commercial laser stripping equipment to market for consumer electronics in the 1990 ’ s and 00 ’ s . Along the way crystals , rather than gases , were used to produce laser beams for exotic and specific applications .
The question of whether to use a laser stripper is akin to asking whether a hammer or screwdriver should be used . It really depends on the task at hand . Laser technology is not as versatile as blade technology . Blades have three basic functions . They are used to cut insulation , pull it off and also to cut the wire . A laser is a beam of light that can cut insulation , but is
assemblies gained a solid foothold as part of RESCO ’ s business , although it remained a sideline through the 1990 ’ s . Along the way , RESCO secured several barcode scanning lines that were also sold to OEM ’ s .
In 2003 , David came on the scene and purchased RESCO Electronics when John retired . It didn ’ t take long for him to realize that being a relatively small player in the electronics distribution industry was a losing proposition . The harness business was growing , yet there was no real push to market those capabilities . As David recalled , “ We put our focus and resources behind the cable harness and barcode scanning businesses and deemphasized parts distribution .” Fast forward to today , and less than
_____________ Continued on page 22
Basics of Laser Wire Stripping
not used to pull it off , or to cut the wire ( with few exceptions ). Because of cost and functionality , blades are generally the way to go . If there is a reason a blade is not working , then it ’ s time to look at lasers .
There are many things that make lasers attractive . Lasers remove insulation but reflect off the metal conductors . It ’ s a self-limiting technology in that you don ’ t have to worry about dialing in a depth , or damaging the wire . The laser doesn ’ t care about the shape of the wire or the type of insulation . There are no consumables , as with blades , and tough materials like fiberglass can be stripped rather easily . Lasers are also practical where conductor sizes are quite small , like the size of a hair ; or where insulation is bonded to the wire and would otherwise require a scraping or grinding process . The color of the insulation is not an issue as every polymer will absorb light and every metal will reflect . In short , lasers give you the confidence that you will achieve the same result every time .
Lasers can be used to either cut a slit in the insulation , or to vaporize the material altogether . The latter is usually not practical as it is time consuming , and generally leaves a residue from the insulation . This could potentially be an issue for a crimp or solder joint . As previously mentioned , bonded insulation may require to-