PDA

View Full Version : soldering information



RickJ
02-20-2007, 12:37 AM
Does anyone know where the soldering info is?http://forums.parallax.com/images/smilies/hop.gif

parts-man73
02-20-2007, 01:33 AM
Are you looking for a soldering tutorial? or pad layout for the surface mount Propellers?

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Brian Meade

"They who dream by day are cognizant of many things which escape those who dream only by night" - Edgar Poe

RickJ
02-20-2007, 02:15 AM
I wanted to find out about temperatures, methods,etc.
I want to get into SMD aswell.
Thanks.http://forums.parallax.com/images/smilies/jumpin.gif
I do not know what the bouncing ball emoticon means.ˇ : )

Bergamot
02-20-2007, 02:40 AM
This is a nice tutorial:

www.sparkfun.com/commerce/present.php?p=SMD-HowTo-2 (http://www.sparkfun.com/commerce/present.php?p=SMD-HowTo-2)

RickJ
02-20-2007, 03:18 AM
I apprieciate it. What is the temperature necessary for a home made smd oven setup?
Is it dependent on the oven?

QuattroRS4
02-20-2007, 03:23 AM
Elektor did an SMD reflow oven article a bit ago - got the mag somewhere - so I gave a look at their site and there it was ...

http://www.elektor-electronics.co.uk/default.aspx?tabid=28&art=52955

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
'Necessity is the mother of invention'

parts-man73
02-20-2007, 04:35 AM
Sparkfun has a similar kit to make your own reflow toaster oven. I had thought of doing a similar kit, but using a Propeller to control it. But I have too much going on right now to take on a project like that. (I lost all the CAM files for SpinStudio due to a hard drive crash, I'm working on a new and improved version now, but it's significantly delayed my progress. Lesson learned? make backups!!!)

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Brian Meade

"They who dream by day are cognizant of many things which escape those who dream only by night" - Edgar Poe

RickJ
02-20-2007, 01:22 PM
http://forums.parallax.com/images/smilies/scool.gifˇ It would be nice to be able to solder at one time an IC that has a large number of pins.
I hopeˇI could get at least 80 percent of the leads done.

ˇ

QuattroRS4
02-20-2007, 01:30 PM
Rickj,
If I find that Elecktor article I can knock it on to you - if you are interested..

also see these:
http://www.engineeringlab.com/

Manual soldering smd:
http://www.youtube.com/watch?v=Bq7fXcAMRcQ

http://www.youtube.com/watch?v=e5qYG95bbz8&mode=related&search=
ˇ- not sureˇI like the length of time the Iron is at the pins here though


Tools at:
http://www.howardelectronics.com/tools.html

There also was a cool video of manual soldering an smd component with paste somewhere on the parallax forums can't find it now though - I am sure someone will ....

Quattro





▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
'Necessity is the mother of invention'

Post Edited (QuattroRS4) : 2/20/2007 6:26:27 AM GMT

simonl
02-20-2007, 09:19 PM
Here it is :) drag SMD solderingˇvideo (http://www.heinc.com/xytronic/Images/Drag%20Soldering%20107.wmv)ˇˇ(it's in the sticky topic on safe 5V cnx... http://forums.parallax.com/showthread.php?p=585920)

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Cheers,

Simon

BTW: I type as I'm thinking, so please don't take any offense at my writing style http://forums.parallax.com/images/smilies/smile.gif

-------------------------------
www.norfolkhelicopterclub.co.uk (http://www.norfolkhelicopterclub.co.uk)
You'll always have as many take-offs as landings, the trick is to be sure you can take-off again ;-)

Graham Stabler
02-20-2007, 09:33 PM
I used to solder panels of 9 small DC-DC converters simultaneously using a domestic iron. You put paste on the pads, place the parts and pop on the iron, the solder reflows and you remove. No good for double sided but works great for single, the board thickness makes the warm up and cool down a bit more smooth than normal too.

Graham

RickJ
02-21-2007, 12:34 AM
Thanks to all. I see that the users here are good people.

QuattroRS4
02-23-2007, 10:20 PM
RickJ,
I eventually found that article that I mentioned - I have attached it here.. I have a 300DPI Colourˇversionˇscanned in for youˇso send me a PM if you want me to email it on to you .Its about (36MB)

Regards,
ˇˇˇˇˇˇˇˇˇˇ Quattro

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
'Necessity is the mother of invention'

Post Edited (QuattroRS4) : 2/23/2007 4:49:09 PM GMT

Bergamot
02-23-2007, 11:02 PM
simonl said...
Here it is :) drag SMD soldering video (http://www.heinc.com/xytronic/Images/Drag%20Soldering%20107.wmv) (it's in the sticky topic on safe 5V cnx... http://forums.parallax.com/showthread.php?p=585920)


I've always been a little scared of drag soldering; it just seems like it would be way too easy to accidentally create a short.

parts-man73
02-23-2007, 11:34 PM
I always use solderwick on SMT chips. especially if it's a really fine pitch package. Just lay the wick on top of the leads down one side and apply heat. Then repeat for the other side. It will wick out any solder between the leads, it also removes the solder from on top of the leads, but don't worry, the solder under the leads will not wick out.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Brian Meade

"They who dream by day are cognizant of many things which escape those who dream only by night" - Edgar Poe

RickJ
02-24-2007, 08:04 AM
What is drag soldering?
Can anyone explain Wave Soldering?
It looks like the board is up side down.

Looking at my original post.
If I Reflow Solder a 1 CM Propellor chip ( QFP, I believe ), How do I know what temperatures to use?



Post Edited (RickJ) : 2/24/2007 12:11:34 AM GMT

Paul Baker
02-24-2007, 08:14 AM
Drag soldering video:ˇ http://www.heinc.com/xytronic/Images/Drag%20Soldering%20107.wmv
Wave soldering is a professional process which requires big and expensive machinery.

The reflow profile is dependent on the paste used.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

BTX
02-24-2007, 11:51 AM
Hi all.
Does somebody knows, what is exactly that 'gel or paste or ...???' used in the above Paul's sample video ?
I would like to buy some at DigiKey, but I can't find in the catalog, which is it.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Regards.

Alberto.

CJ
02-24-2007, 11:58 AM
liquid flux, I believe

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Who says you have to have knowledge to use it?

I've killed a fly with my bare mind.

Paul Baker
02-24-2007, 12:06 PM
Yes it's flux, you should get either no-clean or water soluble.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

RickJ
02-24-2007, 09:47 PM
What have I started B )

BTX
02-24-2007, 10:51 PM
Thanks guys.
But, is it really liquid ? and it's so viscous, or it's a gel ?
What type can be removed by isopropilic alcohol ?

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Regards.

Alberto.

CJ
02-24-2007, 11:17 PM
to me it looks to be rather fluid, but at that size of drop, the surface tension is the ruling force

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Who says you have to have knowledge to use it?

I've killed a fly with my bare mind.

BTX
02-24-2007, 11:24 PM
Thanks so much CJ.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Regards.

Alberto.

Forrest
02-24-2007, 11:57 PM
You'll find both liquid flux and gel flux. Liquid flux usually has a high percentage of alcohol and evaporates quickly with heat. Once it evaporates, it's easy to create solder shorts when soldering fine pitch SMT devices. Gel flux has a much higher viscosity and doesn't evaporate. For soldering fine pitch SMT components (like the Propeller), I've had better results with gel flux because it's better at preventing shorts while soldering. For gel flux, Google Kester TSF flux

BTX
02-24-2007, 11:59 PM
Oh perfect Forrest !! thanks so much.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Regards.

Alberto.

John R.
02-25-2007, 06:09 AM
RickJ said...

Can anyone explain Wave Soldering?



In a commercial line, the components are all placed. Then the board travels down the automated "conveyor" line.

The "wave" is a basically a "river" of molten solder being circulated. Then a "dam" is put accross the river. As the solder flows over the dam, there is a "wave" that is higher than the rest of the solder.

As the board travels over this area, the wave "floods" the board with molten solder. The solder mask keeps the solder away from where it should be away from, and everything else is soldered.

Simple in concept, kind of trciky in application.

I probably don't have all the little details right, but I think this conveys the jest of it.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
John R.
Click here to see my Nomad Build Log (http://share.crustcrawler.com/JohnR/)

Harley
02-25-2007, 07:45 AM
John R. said...
As the board travels over this area, the wave "floods" the board with molten solder. The solder mask keeps the solder away from where it should be away from, and everything else is soldered.
Simple in concept, kind of trciky in application.
I probably don't have all the little details right, but I think this conveys the jest of it.


This for thru-hole part boards, I think. And only the bottom (solder) side of the board is 'wave soldered'. (Don't think they 'flood' the component side any!) And this would not support any SMD parts on the solder side of the pcb.

Think this clarifies the picture a bit. (I've been wrong a 'few times' before.)

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Harley Shanko
h.a.s. designn

rtowler
02-27-2007, 02:14 AM
Thanks to everyone who posted links. You've encouraged me not to fear the SMD.

I can see using an iron for "one off" projects or a repair here or there, but I need to do small runs with pin counts high enough where iron work is out of the question. Those links suggested toaster oven mods, hot air, and electric frying pans and there were pros and cons for each. My design is stable enough to invest in a mask, so that's isn't a concern. I'm just wondering what technique I should pursue. I am leaning towards using hot air since my runs are small enough and I would seemingly get a 2 for 1 since I could use the hot air tool for repair work too. But I wonder about the quality of the soldering since you would have very little control of the profile. I also wonder if you can easily use hot air on those really teeny components. Is the solder paste enough to hold them in place?

I know there is no one size fits all approach, but what are you DIY'ers really using?

-Rick

RickJ
02-27-2007, 04:19 AM
This has been a good thread.
I down loaded software from Diptrace today and got it on my computer. It is the freeware version. I get a faster down load at school.
I have a toaster oven for the SMT soldering. I hope it works.
I wish I could get a logic analyzer.
Then a cnc router to finish it off.

I hope to have something built using smt by summer.
I have been looking to build something with 68K, PPC, Propeller, and Ubicom chips.
I have a lot of work ahead.
Later, Rick.

Paul Baker
02-27-2007, 04:28 AM
Rick, make sure that once you use the toaster oven for solder reflow, never ever use it for food preperation again (use a sharpie to indicate this on the top of the oven if you have to). You will be poisoning your food (and yourself) if you do.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

parts-man73
02-27-2007, 04:29 AM
I've heard of a method (haven't tried it yet) or doing SMT with hot air using an inexpensive embossing tool, and a beverage warmer. The embossing tool can be had for $25-30 from a local craft store (A.C. Moore, Micheal's or the like, or ebay???) Here's a link to the site explaining the process.

www.zianet.com/erg/SMT_Soldering.html (http://www.zianet.com/erg/SMT_Soldering.html)

As many different directions that this thread was gone... you can see everyone has a different way of doing it. Some may be easier than others, and some better suited for different purposes.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Brian Meade

"They who dream by day are cognizant of many things which escape those who dream only by night" - Edgar Poe

Paul Baker
02-27-2007, 04:35 AM
Dont follow his directions on the application of paste, he places way too much on the pads. Hand application is ok for a prototype (just use about 1/8th the amount he uses), but invest the money on a stencil if doing even small production runs.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

Post Edited (Paul Baker (Parallax)) : 2/26/2007 9:05:26 PM GMT

parts-man73
02-27-2007, 04:36 AM
btw... there's a link on that page to purchase solder paste in small syringes. A little goes a long way...

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Brian Meade

"They who dream by day are cognizant of many things which escape those who dream only by night" - Edgar Poe

mahjongg
02-27-2007, 09:42 AM
Harley,

believe it or not but SMT components are often wave soldered! especially when boards are used with SMT components on both sides.

First the "top side" SMT components are soldered to the board in the "normal" way, with solder paste applied through a solder paste mask, and then reflow soldered in an oven.

After that the board is turned downside up, and a robotic system, similar to that which places the SMT components on top of the solder paste pads, disposes little droplets of glue in-between the two pads of a SMT component (such as a resistor of capacitor), or in the middle of a larger component (IC, transistor). Then The SMT components are placed on top of the glue droplets. After the glue has hardened the board can be turned over without the glued components falling off, now the glued SMT components can be wave soldered, the solder of the already soldered SMT components on the top side might re-melt, but that is normally not a problem.

Some precautions must be taken while designing a PCB with wave soldered SMT, for example so that small components do not lie in the "shadow" of nearby large ones that prevent the wave to reach them. Also some of the copper pads that are last to be soldered are often made somewhat larger, so they can take excess solder without problems. Integrated circuits are often rotated diagonally (45 degrees), so the solder flows better over their pins.


Parts_man73,

I personally once did some SMT soldering with a modified hot air paint burner, it works, but you need to make sure the airflow is reduced, or you will blow off all the components from the board, also you need to set the paint burner as low in temperature as possible, you want to solder the board, not reduce it to ashes.
One way to solve both problems is to put a filament lamp with a similar wattage to the paint burner in series with it, so the paint burner gets only halve the wattage.


by the way,
The easiest way to solder SMT IC's (Flat pack etc), in my opinion, is to use a soldering iron with a tip that has a "hollow" in the end (specially made for the purpose), the hollow is filled with a tiny droplet of molten solder, and that droplet is drawn across the pins of an integrated circuit.

Very important is to clean the tip of the soldering iron regularly on a wet sponge. And to keep some solder-wick at hand to remove excess solder, and a syringe with solder flux is also often invaluable.

Mahjongg

DogP
02-27-2007, 01:24 PM
Not that I totally recommend this method, but for most SMT desoldering, I use a heat gun connected to an autotransformer (adjustable AC power supply)... that allows me to control the heat pretty well (sorta like the light bulb in series except more adjustable). And depending on the board, I also have a hotplate (like you'd use on a buffet table) which I use for preheating the board. I have used the hotplate to solder and desolder, but it tends to burn the PCB a little bit if you get it hot enough to melt the solder on the other side.

Once the board is preheated, I take the heat gun and melt the solder, and then use a handi-vac (suction pickerupper tool) to pull the chip. Of course soldering is easier... just do the opposite, except placing the chip before the solder is melted. Or I use a very fine tipped soldering iron, or the drag soldering method with a lot of flux.

Just another option, depending what hardware you already have on hand... if you don't already have some of this stuff, it may be cheaper to just buy a hot air tool. The heat gun is nice though since it's able to heat most chips all at the same time. Just make sure you practice on junk boards before trying it on something important :) .

Pat

rtowler
02-28-2007, 01:06 AM
Pat, thanks for the reply. I like your approach. I was a bit weary of the hot-plate/fry pan only approach and the hot air only approach but using them together compliments the pros and minimizes the cons.

The only electronics tools I have in my home workshop are a natty old fire starter radio-shack soldering iron I got when I was 12, and a couple of old multi-meters purchased around the same time http://forums.parallax.com/images/smilies/tongue.gif I have the basics in my shop at work and do thru-hole work there, but I'm putting together a shop at home so everything will be new (or new used).

-R

parts-man73
03-02-2007, 07:52 AM
There's a new SMD soldering video that was just posted on SparkfunSparkFun (http://www.sparkfun.com/commerce/categories.php)

Not sure exactly how they are doing it, or how it turns out, anyone care to guess as to what we are seeing there?

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Brian Meade

"They who dream by day are cognizant of many things which escape those who dream only by night" - Edgar Poe

mahjongg
03-02-2007, 08:32 AM
In the picture you can see that a SMT IC is first soldered with one of it's corner pins to the board. This is done so it can't move anymore. One main problem with soldering SMT components is that they are so light that the smallest movement sends the component flying. By first soldering the IC to the board with one pin, the IC is fixated. Next the three other corner pins are done, to make sure the IC is mounted flat on the PCB, and also to make sure it wont com loose when you melt the solder on one side of the IC again.

The big trick shown here is the use of "solder wick" (thin braided copper wires dipped in flux).
Normally solder wick is used for de-soldering, by sucking the solder from a solder joint into the wick.
But in this application the solder wick is flooded with solder, so it is used to transfer the heath to all the pins on one side of the IC, and also to "wet" all the pins with solder because the solder naturally flows by capillary force through the wick.
An excess of solder over the whole side of the IC, can be removed by moving the wick a bit to a "clean" part of the wick.
Then the other side is done, and the IC is soldered.

Martin (Mahjongg).

RickJ
03-14-2007, 09:58 AM
Has anyone got any new developments? Sorry to be gone for a while. I left my machining job to go back to computer building. I need to find another job soon. I am begining to dislike where I am working. I like building computers but my employer is not providing me with the necessary tools. Sorry to complain.
Later.

Paul Baker
03-16-2007, 12:34 AM
Not sure what you mean by new developments, I did find out that we use the temperature profile provided by the manufacturer of solder paste we use when reflowing boards. This is the most critical component of the profile on all boards we make.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

jonduncan
03-16-2007, 04:05 AM
I have a quick question about soldering I want to put the compass on my protoboard and i am wondering how I can solder it then connect it to thr prop once you solder something to the board how do you connect something to one of it's pins?

Paul Baker
03-16-2007, 04:10 AM
You either stuff the wires into the same hole before you solder it or tack solder the wire to the pin that has extended beyond the hole.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

RickJ
03-16-2007, 09:54 AM
I have not done anything myself. I plan to buy a dev. kit for learning how to program a cpld device. Does Parallax have any plans to get into the CPLD or FPGA chips?
Later.

Paul Baker
03-16-2007, 11:00 AM
We did carry Altera FPGAs about a year ago, not enough people bought them so they were discontinued.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)