Cheap And Easy Surface Mount reflow for $21

[moodz]

One of the pains of surface mount is finding a way to solder those little guys ( components) to the PCB or to get them off again. This is particularly so with fine pitch leaded surface mount chips.
I have found the following setup the most efficient and cheap way to process SMT devices.

The following is useful but NOT absolutely necessary.

Fine Tweezers ( ex medical are excellent )
Flux Pen ( from major electronics suppliers )
Magnifying glass. ( I actually use my mobile phone in video mode with zoom on )
Aluminium foil or Teflon sheet ( cooking sheet )

The following items are REQUIRED for this method to be effective.

Solder paste dispenser with fine tip.
Electric Iron ( mine was a $A14 cheapy from Woolworths )
Heat Lamp such as used in bathroom heaters. ( $A6 from hardware supplier )

Below is the SMT work surface ....


Below is the Reflow booster ( ie IR lamp )


Below is cooked board.




Procedure.

1. Turn IRON heat setting to MAX .
2. Mount IRON so flat bottom is level ( I just use it upside down in the box it came in )
3. Turn iron on.
4. Allow iron to reach stable heat ( approx 2 - 5 minutes )
5. Apply solder paste and position components on PCB ( maybe you did this already )
6. Place PCB on hot iron surface ( component side upmost )
7. Wait 20 to 30 seconds for board to heat ( this will vary with size of board etc )
8. Turn on heat lamp about 10 cm above iron surface / PCB & components. May be fix mounted or hand held.
7. Should see solder paste reach liquidus ( ie melt ) in about 10 to 20 seconds.
8. When all joints have reflowed ( move the light around a bit if necessary ) turn light off
9. Wait further 10 seconds then slide board off hot plate carefully or just turn the iron off and cool with slight airflow.
10. Your done !

TIP use a pair of sunglasses when light is on ( it is only Infrared light however it is a bit blinding in a dark workshop ).

Use a similiar process to remove components.

Cut 'Shadow Masks' out of tin foil or teflon sheet to work on individual components.

Add a thermocouple to the IRON to monitor for fancy monitoring or even control. ( I have not tried this )

I have use very fancy $2000 inert gas rework stations but this method blows them into the weeds.

I would be interested on any feedback on this method. ( I did not invent it ... I just simplified it )

Moodz.

[WM6]

One of the pains of surface mount is finding a way to solder those little guys ( components) to the PCB or to get them off again. This is particularly so with fine pitch leaded surface mount chips.
I have found the following setup the most efficient and cheap way to process SMT devices.

The following is useful but NOT absolutely necessary.

Fine Tweezers ( ex medical are excellent )
Flux Pen ( from major electronics suppliers )
Magnifying glass. ( I actually use my mobile phone in video mode with zoom on )
Aluminium foil or Teflon sheet ( cooking sheet )

The following items are REQUIRED for this method to be effective.

Solder paste dispenser with fine tip.
Electric Iron ( mine was a $A14 cheapy from Woolworths )
Heat Lamp such as used in bathroom heaters. ( $A6 from hardware supplier )

Below is the SMT work surface ....
[ATTACH]12441[/ATTACH]

Below is the Reflow booster ( ie IR lamp )
[ATTACH]12442[/ATTACH] [ATTACH]12443[/ATTACH]

Below is cooked board.

[ATTACH]12444[/ATTACH]


Procedure.

1. Turn IRON heat setting to MAX .
2. Mount IRON so flat bottom is level ( I just use it upside down in the box it came in )
3. Turn iron on.
4. Allow iron to reach stable heat ( approx 2 - 5 minutes )
5. Apply solder paste and position components on PCB ( maybe you did this already )
6. Place PCB on hot iron surface ( component side upmost )
7. Wait 20 to 30 seconds for board to heat ( this will vary with size of board etc )
8. Turn on heat lamp about 10 cm above iron surface / PCB & components. May be fix mounted or hand held.
7. Should see solder paste reach liquidus ( ie melt ) in about 10 to 20 seconds.
8. When all joints have reflowed ( move the light around a bit if necessary ) turn light off
9. Wait further 10 seconds then slide board off hot plate carefully or just turn the iron off and cool with slight airflow.
10. Your done !

TIP use a pair of sunglasses when light is on ( it is only Infrared light however it is a bit blinding in a dark workshop ).

Use a similiar process to remove components.

Cut 'Shadow Masks' out of tin foil or teflon sheet to work on individual components.

Add a thermocouple to the IRON to monitor for fancy monitoring or even control. ( I have not tried this )

I have use very fancy $2000 inert gas rework stations but this method blows them into the weeds.

I would be interested on any feedback on this method. ( I did not invent it ... I just simplified it )

Moodz.

Very useful tip moodz, thank you.

[moodz]

Another useful tip ...

Do not under any circumstances ... use the Bosses IRON or you will not be mounting anything for some time to come

Moodz

[WM6]

Do not under any circumstances ... use the Bosses IRON or you will not be mounting anything for some time to come

Moodz

What is Bosses IRON?

[silverdog]

I think he means the Wife's !!

[Altra]

Moodz,

I use a similar method. I got a electric skillet from Wallymart, $19.95. It works great and no need to use an IR lamp. I got the idea from a Sparkfun tutorial.
http://www.sparkfun.com/commerce/tut...utorials_id=59


I also have found that with care you can do same board more than one time. Example, apply your solder and place the caps and resistors, reflow these only. After the board cools repeat with the IC's, transistors etc. This way you can manage the fine pitch parts placement and not worry about a bunch of resistors and caps.

It seems to me the most important step is applying the solder to the pads. Too little no connection, too much you get bridging and tumbstones. Overall, this is a great method, and beats hand soldering and even expensive reflow ovens for most small jobs.

P.S. Keep reporting on your FPGA project, very interesting!

Regards
Mark

[moodz]

I think he means the Wife's !!

[moodz]

Moodz,

I use a similar method. I got a electric skillet from Wallymart, $19.95. It works great and no need to use an IR lamp. I got the idea from a Sparkfun tutorial.
http://www.sparkfun.com/commerce/tut...utorials_id=59


I also have found that with care you can do same board more than one time. Example, apply your solder and place the caps and resistors, reflow these only. After the board cools repeat with the IC's, transistors etc. This way you can manage the fine pitch parts placement and not worry about a bunch of resistors and caps.

It seems to me the most important step is applying the solder to the pads. Too little no connection, too much you get bridging and tumbstones. Overall, this is a great method, and beats hand soldering and even expensive reflow ovens for most small jobs.

P.S. Keep reporting on your FPGA project, very interesting!

Regards
Mark

Thanks Mark .... I will try out your 'double reflow' tip ..

Regards,

Paul.

[jwms]

Have stuck larger components to board with tiny!! drop of superglue to get the most number of components on the board before placing on the iron. I do not like heating parts too many times and it keeps them in place while adding others. Less chance of mis-alignment.