| Author |
Message |
    
Sg569
Junior Member
Username: Sg569
Post Number: 34
Registered: 12-2004
| | Posted on Friday, January 14, 2005 - 12:06 pm: | 
|
Just wanting to know why y'all dislike cold solder joints so much, I have never had a prob w/ them. That is the way I learned to solder, and I learned from an elec. tech for (what is now) Lockheed/Martin
Just wanted to ask.
Thanks. |
Bruce
Senior Member
Username: Bruce
Post Number: 2089
Registered: 9-2003
| | Posted on Friday, January 14, 2005 - 2:53 pm: |
|
Wave solder boards DO have a problem.... |
Sg569
Junior Member
Username: Sg569
Post Number: 40
Registered: 12-2004
| | Posted on Friday, January 14, 2005 - 4:45 pm: |
|
Bruce, what is a wave solder board?? |
Bruce
Senior Member
Username: Bruce
Post Number: 2093
Registered: 9-2003
| | Posted on Friday, January 14, 2005 - 10:46 pm: |
|
ALMOST ALL HAM / CB RADIOS ARE MASS PRODUCED NOT HAND SOLDERED. These boards are done on a automated machine ( WAVE SOLDERED ) it is a VERY cost effective way to build boards HOWEVER having in my youth worked on a military / space production line and soldered my own share they just never have that human touch of quilty.
The board is soldered by the machine not a person because the board is not even touched from start to finish by a person you are depending on a machine to do the entire job. SMT ( like the 2950 DX and mag-257 ) boards are good examples of this way of building new radios.
If someone knows of a radio not built this way in the last 5 years i would like to know |
Sg569
Junior Member
Username: Sg569
Post Number: 43
Registered: 12-2004
| | Posted on Saturday, January 15, 2005 - 3:16 pm: |
|
Bruce thanks for teaching me something new.
|
Tech833
Moderator
Username: Tech833
Post Number: 955
Registered: 8-2002
| | Posted on Sunday, January 16, 2005 - 12:26 pm: |
|
Laser soldering is the way most SMT boards are done, BTW. You should also know that surface mount parts are MUCH more robust than their 'thru-hole' counterparts. I would trust the longevity and stability of a 2950DX over a radio not using SMT parts.
I had a 2950DX and I was VERY impressed with the design and quality of construction. Please, do NOT let SMT be a deterrent for you. For equipment that will stand up the the vibration of a big rig and have the stability and tempurature survivability of military equipment but without the Pentagon price tag, choose something built with SMT. |
Bruce
Senior Member
Username: Bruce
Post Number: 2099
Registered: 9-2003
| | Posted on Sunday, January 16, 2005 - 3:18 pm: |
|
833 when i worked in production we used wave soldering but that was 15 years ago now interesting on laser ill have to check it out. |
Gijoe
Member
Username: Gijoe
Post Number: 59
Registered: 4-2002
| | Posted on Sunday, January 16, 2005 - 9:57 pm: |
|
Check out this video of melted solder onboard the International Space Station.
http://science.nasa.gov/headlines/y2004/16aug_solder.htm?list1193276
Click on one of the video options under the two pictures.
Joe |
Mdiver
Intermediate Member
Username: Mdiver
Post Number: 204
Registered: 11-2003
| | Posted on Monday, January 17, 2005 - 12:03 pm: |
|
Tech 833
your right on the 2950dx so far this radio radio is the best I have for staying on Freq.and with no problems.
Steve-CEF-252 |
Sg569
Junior Member
Username: Sg569
Post Number: 44
Registered: 12-2004
| | Posted on Wednesday, January 19, 2005 - 11:37 am: |
|
That's pretty cool Joe.
|
Supertech1
New member
Username: Supertech1
Post Number: 9
Registered: 1-2005
| | Posted on Thursday, January 20, 2005 - 9:55 pm: |
|
Tech833,
If you ever had to swap out a smt resistor or gosh forbide a transistor---by hand!- You would have a completely new opinion about it. I modified my bearcat 2500xlt scanner to recieve cell phone freq. and let my tell you--it was quite a new, fustrating experience. I have had fun soldering for over 30 years and THAT was NOT fun. Quite the challenge working with fine tweezer, special low temp soldering iron and a magnifying glass---felt like brain surgury. (btw--I was successful);) |
Chad
Member
Username: Chad
Post Number: 94
Registered: 11-2004
| | Posted on Friday, January 21, 2005 - 9:38 am: |
|
Supertech,
SMT is not that bad, there is a learning curve and unfortunately our eyes never get better.
I have spent countless hours working on SMT and can vouch that it was a pain at first but once I got used to it I found it easier in that I was not constantly flipping the board over (or heavy equipment) you get to work on one side at a time. With a little practice one can become very proficient with it.
A rolled piece of masking tape is handy for holding parts, Non-magnetic everything, the components are light weight and will stick to magnetized tools. Solder removal braid is your best friend. Have a little patience and I think you will you will do well with it!
Go to a local repair shop and get a dead SMT board to practice, You will be kicking butt in no time.
Chad
Tech 833 adds- I wear a magnifying visor when working with SMT. Helps a lot! |
Tech833
Moderator
Username: Tech833
Post Number: 957
Registered: 8-2002
| | Posted on Friday, January 21, 2005 - 10:13 am: |
|
Supertech,
I work on SMT boards all the time. Yes, I have changed out resistors. Also, diodes, IC's, transistors, diodes, etc. When I mentioned that I have done SMT prototyping, that encompases designing, etching a board, stuffing it with parts, changing parts, installing board mods (jumper wires, cutting traces to add-subtract parts, etc.). That is the ultimate SMT experience! 7 years ago, SMT was scary. Now, I prefer to prototype with SMT over thru-hole. Most of my parts inventory is now SMT. Not only are the parts cheaper by the spool, but the parts are actually stronger and better than thru-hole (DIP).
A good quality magnifying visor is a must. Something with at least 2 levels of magnification that can also be flipped up and out of the way when not needed. Non-magnetic everything too. Sometimes, I use a little blob of flux to hold a part to the end of a toll for placement on the board. Then, a needle on the end of a wood stick to hold the part while I solder one side then the other. After all is done, I spray the board with flux remover to clean it before initial testing.
Want to see a pic of some stuff I have built with SMT? |
Chad
Member
Username: Chad
Post Number: 95
Registered: 11-2004
| | Posted on Friday, January 21, 2005 - 11:11 am: |
|
Another thing that holds the component to what I like to call the "prod" is that rubbery stuff used to hold inserts in magazines. It has good lateral adhesion and leaves no residue. FINALLY a use for that gooey stuff that annoys us all!
I usually use a wooden dowel sharpened in a pencil sharpener than dulled a tad as my "prod"
A good worklight is also a must, I too use a magnifying visor, I also have a magnifying lamp and an arm type desk lamp to position close to the work area.
I use compact florescent bulbs as they produce far less heat and keep your hands from sweating as bad.
Some manufacturers use a dab of glue to hold the component down before going through the soldering process, this can be a real pain, I have found careful heat, sureness in your desoldering, and a little wiggling combats this problem. Once again it's practice makes perfect.
|
Bruce
Senior Member
Username: Bruce
Post Number: 2116
Registered: 9-2003
| | Posted on Friday, January 21, 2005 - 11:14 am: |
|
Same here i work on them all day and except for the fact im going blind trying to see thoes little parts there GREAT! |
