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IMDES CREATIVE SOLUTIONS Schulstrasse 21  D-48455 Bad Bentheim /Gildehaus  Germany T:+49(0)5924-997337 E

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  SKYPE marc.van Stralen                                                                                 

© 2019

 

IMDES CREATIVE SOLUTIONS 

 

25 

 

 

4.0 Tips for reflow soldering. 

 

4.1 Soldering errors  

 

Random Solder Balls  
 

4.1.1

 Solder Balls The causes for solder balls are different:  

• The temperature gradient in pre-heating is too high, which causes the solvent in the paste to evaporate violently,  
   ripping out solder paste balls from the print of the paste.  

• The paste print rests on the solder resist. (Wrong pressure or mask too large). Good results are obtained if the   
   print of the paste is reduced by approx. 10 to 15 %).  

• The applied solder paste is too old or of bad or unsuitable quality.  
• The bottom side of the stencil or the screen is not clean, thus depositing paste residues on the assembly surface. 

• Due to a bad wetting of the pad or component the wetting is incomplete. Some paste remains on the assembly in  
   the form of balls.  
• The amount of paste relative to the available pad size is too high. Generally, due to the careful heating with  

   

vapor-phase soldering the solder ball formation is greatly reduced. 

 

 

4.1.2 Wicking-Effect 
 

 
 

 
 

 

 
The wicking effect is the rise of the molten solder on component leads. This disrupts the soldering to the contact 

pad below. The wicking effect is known mostly with infrared or convection machines with very high pre-heating 
speeds. Lately it is found rather frequently with backplane SMD connectors, due to an extremely large amount of 

energy flowing across the pin-area into the metal. Thus the pins reach soldering temperature much faster than the 
pad below.  
1. The wicking effect is mostly caused by bad solder ability of the contact pads on the assembly.  

2. The component leads reach the flow point temperature much faster than the metallization of the substrate. This 
causes the paste to melt and to rise along the leads. In this case, the so-called ‘top heat‘ is too high. The formation 

of the wicking effect may be controlled via the machine technology by lowering the temperature gradient starting 
at approx. 150° C. 

With vapor-phase soldering the wicking effect is practically unknown, because of 

the negligible temperature differences on the printed circuit boards and the components

.  

 

 
 

 

 

 

 

 

Содержание DINO-CONDENS-IT

Страница 1: ...van Stralen 2019 IMDES CREATIVE SOLUTIONS 1 DINO CONDENS IT PROFILER The perfect method to solder SMD components at the highest solder quality Preliminary Owner s Manual Version 2 0Tuesday February 5...

Страница 2: ...nical inaccuracies or typographical errors Information may be changed or updated without notice IMDES CREATIVE SOLUTIONS may make improvements and or changes in the materials machine at any time witho...

Страница 3: ...1 13 2 Installation and commissioning 13 1 13 3 The stainless steel lid with glass observation window 13 1 14 Handling Tips 14 1 14 1 Handling of the DINO CONDENS IT 14 1 14 2 General operating instru...

Страница 4: ...th without N2 Vapor Phase 26 4 1 5 Bridging short circuits or bridges between pads 26 4 1 6 Solder Beads 26 4 1 7 Pop Corning 28 4 1 8 Poor Wetting 28 4 1 9 Voiding 28 5 0 Double Sided Printed Circuit...

Страница 5: ...hall NOT be exceeded under any circumstances 1 1 Technical Data Power Supply Single phase 220 240 Volt 50 60 Hz Power Connector Three Prong Power Connector Max heating capacity 2500 Watt ca 12 A Dimen...

Страница 6: ...the same temperature as the boiling liquid When the assembled printed circuit boards is brought into this space the vapor will condense on the surface because the circuit board has a lower temperatur...

Страница 7: ...ed Circuit Boards with SMD components are were mostly done in an infrared oven possibly with nitrogen as shielding gas to prevent oxidization of solder joints On the introduction of lead free solderin...

Страница 8: ...B regardless of the shape or colour Absolute uniform heating of the PCB Condensation vapour causes a thin liquid film that penetrates to the smallest openings resulting in reliable soldering of BGAs a...

Страница 9: ...d at the bottom of the process chamber 2 Transfer liquid is heated to the boiling point Step 2 The heat transfer liquid Galden is active It boils at 230 C and is in active phase PCB with components is...

Страница 10: ...0 Step 3 1 Temperature of the assembled PCB reaches temperature of the transfer fluid PCB temp Vapour temp 2 Vapour starts to rise again Step 4 1 Reflow process will be terminated by switching off the...

Страница 11: ...ess chamber cover sensor A micro switch monitors if the process chamber cover is present and closed If you open the cover before the end of the process the system is switched off When the there is no...

Страница 12: ...ch DINO CONDENS IT Item FLEX DINO CONDENS IT 1 no Lid Cover with glass window 1 no This owner s manual 1 no AC Power cable 1 no Dipstick to measure the Galden Level in the process chamber 1 no Pump 10...

Страница 13: ...hange of air underneath the DINO CONDENS IT 1 13 3 The stainless steel lid with glass observation window GALDEN is an expensive liquid and hence we have optimized the DINO CONDENS IT to have the lowes...

Страница 14: ...right away 1 14 1 Handling of the DINO CONDENS IT With the construction of DINO CONDENS IT great attention was given to a simple reliable and straightforward design for ease of handling and low cost...

Страница 15: ...without prior consultation with IMDES CREATIVE SOLUTIONS Use personal protection while operating the system Observe all applicable national regulations and safety regulations for accident prevention a...

Страница 16: ...rning GALDEN decomposes when heated above 295 C 563 F into harmful components The DINO CONDENS IT does NOT check automatically if there is sufficient level of GALDEN in the process chamber Therefor yo...

Страница 17: ...move the soldered part and product carrier We strongly discourage the use of pliers tweezers or similar tools to remove the soldered parts as they may slip from the tool and fall into the liquid Galde...

Страница 18: ...n this zone The work piece surface is heated to the temperature of the boiling liquid vapour The temperature of the vapor is determined by the temperature of the boiling point of liquid and will not e...

Страница 19: ...s IMDES CREATIVE SOLUITIONS Copy right Paul Keizer Ver 1 15 or an other Ver Version release No When pressing the green key the soldering process starts with the last saved profile in Eeprom and starts...

Страница 20: ...and red key simultaneously to enter the next menu If you want to activate the Anti tombstone mode you must enter values into the AntiTombStTime Menu If you do not want to change anything in a menu yo...

Страница 21: ...low modus the machine is continually sensing the Galden Temperature and automatically switch of de heaters and starting the cool down if the Galden temperature exceeds its limits ANTI TOMBSTONE REFLOW...

Страница 22: ...pressing the plunger of the syringe 9 Repeat the procedure until process chamber is empty 10 When the process chamber is empty place the DINO CONDENS IT in horizontal position 11 The DINO CONDENS IT...

Страница 23: ...from the delivery date The warranty is void if The machine is not operated as per the procedure detailed here in and or operated without the liquid Galden filled in the process chamber If any modific...

Страница 24: ...em in earning capacity It is here where the vapor phase as the only soldering system offers the inestimable advantage to continue using all hereto known and processed materials The costs of the machin...

Страница 25: ...oo high Generally due to the careful heating with vapor phase soldering the solder ball formation is greatly reduced 4 1 2 Wicking Effect The wicking effect is the rise of the molten solder on compone...

Страница 26: ...far apart to prevent the surface tension of the solder to pull the component to one side This will make it impossible to produce a solder contact on its other side due to an insufficient contact area...

Страница 27: ...is oxidation influence may be well observed in convection machines Switching off the nitrogen supply is a frequently used trick to eliminate tombstoning with known failure prone assemblies Without nit...

Страница 28: ...The dangerous of the popcorn effect is that it is not immediately detected as it occurs under the device for example are BGAs Vapor phase soldering significantly reduces this error probability 4 1 8...

Страница 29: ...costs As the adhesives are cured without oxygen no oxides will form on the printed circuit boards which results in improved solder quality Advantage of having a single profile to cure adhesive and to...

Страница 30: ...inly laid out designed with small chips 7 2 Step 1 We start with Screen printing the B side of the double side PCB with smallest components Placing the components Reflowing PCB Side B with the compone...

Страница 31: ...f the A side with large components To screen the A side of the PCB you need to use a PCB support holder Use for the PCB support holder material that is thicker than the populated PCB and thick enough...

Страница 32: ...ndoffs See Fig below You ll damage the SMT solder joints from the first reflow if you lay the board directly on the product carrier Standoffs You can use any material that can withstand the condensati...

Страница 33: ...OLUTIONS Schulstrasse 21 D 48455 Bad Bentheim Gildehaus Germany T 49 0 5924 997337 E info imdes de www imdes de SKYPE marc van Stralen 2019 IMDES CREATIVE SOLUTIONS 33 7 6 DUAL SIDED MIXED SMD THT ASS...

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