CaptKirk
New elf
So I did a test run of 10 last night to work out the process and not ruin a whole panel. Glad I did.
You should use something like this to see:
http://dx.com/p/light-head-magnifying-glasses-with-4-pieces-different-multiple-lens-2-aaa-52687?item=70
Small tip tweazers worked really well to position parts. A chip vacuum pen might be better:
http://dx.com/p/ic-chip-vacuum-sucker-pen-set-for-electronics-diy-4-piece-set-15080?item=1 if the tip is small enough. The tweazers are handy for flipping over parts that inconvieniently depackage upside down. I like the resistors all number side up, and the chips HAVE to be right side up. A small plate (like a tea cup saucer) can hold parts and not let them get away- use something, not the table, parts can get blown or swept off the table too easily!!
TIP: for part positioning: the constant current chip in this batch has a white line toward one edge and that IS pin 1. The PICs have a white dot near pin 1. Resistors go either way- dont mix them up!!
Also a dental pick will be handy, like:
http://dx.com/p/stainless-steel-acne-blackhead-removal-needle-19881
or
http://www.widgetsupply.com/product/XTC3-DD3105C.html?gclid=CJSu1PWauLECFQ5ThwodEC8AwQ
to fine tune part placement or cleanup paste.
Tip: resistors get a dot or blob of paste - not more! chips get a line of paste like squeezing toothpaste out across the pins on the outer edges of the pads only much MUCH smaller. You would think that would short, but on reflow the solder gets sucked to the chip pads and pins like magic.
Decided to griddle reflow the top of the board because it had more parts. That went well especially because the griddle I used also can grill (ala Foreman Grill but with flat plates) thus it folds! That worked sweet.
The dental pick or tweazers can help nudge reluctant parts into place once the paste is flowing.
Only had a couple of shorts (easy to see and correct) with my small Weller solder tip and a solder sucker which only sucked the excess solder if the soldering iron was left heating. It left a perfect solder joint.
Now rethinking doing the top first because of the PIC pin pitch. The PIC is a PITA to hand solder especially if you decide to use a toothpick to apply the paste instead of an applier syringe. I have one but I cleaned it BEFORE I decided to do the back parts and I didn't want to clean it again (BIG MISTAKE - USE THE SYRINGE!!!). Wow what a mess. Had trouble getting the PIC to position properly with hand soldering. Managed on 8, got the ninth connected by the Grace of God (it sure ended up in a funny position shoved all the way to one side of the pads), and the tenth was an utter failure. The PIC initially soldered on one side off by one pad but the other side was lined up (picture it at an angle across the footprint). Well I figured on just heating and sliding but in the process I broke off a PIC pin and pulled up the pad because I just could not get the off kilter pins hot enough at the same time so I forced it and snap. Ah well that is all part of the fun. Maybe if I could have found my heatgun... <sigh>
The programming went well. I wished I had looked on THIS forum first for a bigger variety of pre-built firmware but found the bottom three files found here on the author's site (THANK YOU for posting!!). Found I needed to apply pressure to the board to get the temporary programming header to make connection but that is easy. If the PIC was recognized, it programmed and worked. Dang these are BRIGHT.
I now have nine working strobes and one lost cause. Hopefully my success rate increases with a full panel.
What I recommend:
-Use a head magnifier which ends up being more convienent than a magnifying light. I have this one:
http://dx.com/p/light-head-magnifying-glasses-with-4-pieces-different-multiple-lens-2-aaa-52687?item=70 and it is nice because you can change the magnification. It is nice quality at a good price.
-A Solder Paste syringe is essential to prevent a mess.
-Use a solder sucker (to correct messes) like:
http://dx.com/p/electronics-diy-disordering-pump-82431?item=3
-Use tweazers and/or a chip vac pen to place parts
-Dental pick to do fine tune and paste cleanup, but a toothpick can work also but I like the feel of steel in my hands when working ;-)
-Griddle reflow works nice.
-A soldering iron designed for surface mount like work is necessary. I have a Weller EC1302a with a tiny tip hooked to a EC2002 digital control unit I got out of the garbage at work because it needed a $9 ferrule. I found the right Weller tips on closeout at Frys Electronics around the same time for $.10 each (Yes I bought them out but they only had 4 available dang it.) The tiniest tip on my trust Hakko is gigantic compared to the tips on this iron- it is amazing the difference. You NEED the right tip/iron to do this!!
That is all I can think of- thanks for reading.
You should use something like this to see:
http://dx.com/p/light-head-magnifying-glasses-with-4-pieces-different-multiple-lens-2-aaa-52687?item=70
Small tip tweazers worked really well to position parts. A chip vacuum pen might be better:
http://dx.com/p/ic-chip-vacuum-sucker-pen-set-for-electronics-diy-4-piece-set-15080?item=1 if the tip is small enough. The tweazers are handy for flipping over parts that inconvieniently depackage upside down. I like the resistors all number side up, and the chips HAVE to be right side up. A small plate (like a tea cup saucer) can hold parts and not let them get away- use something, not the table, parts can get blown or swept off the table too easily!!
TIP: for part positioning: the constant current chip in this batch has a white line toward one edge and that IS pin 1. The PICs have a white dot near pin 1. Resistors go either way- dont mix them up!!
Also a dental pick will be handy, like:
http://dx.com/p/stainless-steel-acne-blackhead-removal-needle-19881
or
http://www.widgetsupply.com/product/XTC3-DD3105C.html?gclid=CJSu1PWauLECFQ5ThwodEC8AwQ
to fine tune part placement or cleanup paste.
Tip: resistors get a dot or blob of paste - not more! chips get a line of paste like squeezing toothpaste out across the pins on the outer edges of the pads only much MUCH smaller. You would think that would short, but on reflow the solder gets sucked to the chip pads and pins like magic.
Decided to griddle reflow the top of the board because it had more parts. That went well especially because the griddle I used also can grill (ala Foreman Grill but with flat plates) thus it folds! That worked sweet.
The dental pick or tweazers can help nudge reluctant parts into place once the paste is flowing.
Only had a couple of shorts (easy to see and correct) with my small Weller solder tip and a solder sucker which only sucked the excess solder if the soldering iron was left heating. It left a perfect solder joint.
Now rethinking doing the top first because of the PIC pin pitch. The PIC is a PITA to hand solder especially if you decide to use a toothpick to apply the paste instead of an applier syringe. I have one but I cleaned it BEFORE I decided to do the back parts and I didn't want to clean it again (BIG MISTAKE - USE THE SYRINGE!!!). Wow what a mess. Had trouble getting the PIC to position properly with hand soldering. Managed on 8, got the ninth connected by the Grace of God (it sure ended up in a funny position shoved all the way to one side of the pads), and the tenth was an utter failure. The PIC initially soldered on one side off by one pad but the other side was lined up (picture it at an angle across the footprint). Well I figured on just heating and sliding but in the process I broke off a PIC pin and pulled up the pad because I just could not get the off kilter pins hot enough at the same time so I forced it and snap. Ah well that is all part of the fun. Maybe if I could have found my heatgun... <sigh>
The programming went well. I wished I had looked on THIS forum first for a bigger variety of pre-built firmware but found the bottom three files found here on the author's site (THANK YOU for posting!!). Found I needed to apply pressure to the board to get the temporary programming header to make connection but that is easy. If the PIC was recognized, it programmed and worked. Dang these are BRIGHT.
I now have nine working strobes and one lost cause. Hopefully my success rate increases with a full panel.
What I recommend:
-Use a head magnifier which ends up being more convienent than a magnifying light. I have this one:
http://dx.com/p/light-head-magnifying-glasses-with-4-pieces-different-multiple-lens-2-aaa-52687?item=70 and it is nice because you can change the magnification. It is nice quality at a good price.
-A Solder Paste syringe is essential to prevent a mess.
-Use a solder sucker (to correct messes) like:
http://dx.com/p/electronics-diy-disordering-pump-82431?item=3
-Use tweazers and/or a chip vac pen to place parts
-Dental pick to do fine tune and paste cleanup, but a toothpick can work also but I like the feel of steel in my hands when working ;-)
-Griddle reflow works nice.
-A soldering iron designed for surface mount like work is necessary. I have a Weller EC1302a with a tiny tip hooked to a EC2002 digital control unit I got out of the garbage at work because it needed a $9 ferrule. I found the right Weller tips on closeout at Frys Electronics around the same time for $.10 each (Yes I bought them out but they only had 4 available dang it.) The tiniest tip on my trust Hakko is gigantic compared to the tips on this iron- it is amazing the difference. You NEED the right tip/iron to do this!!
That is all I can think of- thanks for reading.
