Shop OBEX P1 Docs P2 Docs Learn Events
Protoboard solder problems — Parallax Forums

Protoboard solder problems

max72max72 Posts: 1,155
edited 2010-03-11 01:16 in Propeller 1
I have some issues when soldering my USB proto Boards.
The solder is not willing to stick to the pads as it usually does. Moreover I received with the proto board a couple of X-bee adapters. I assembled the adapters in no time, and used the same male headrs form the set shipped with the adapters on the proto board. So everything is the same, iron, flux, and components.
I was able to solder the header on the board using another flux, more aggressive (I'm also using flux-core solder).
I never had problems, even with veroboards or protoboards old and stored in adverse conditions.

Is someone else experiencing this problem?

Massimo

Comments

  • John R.John R. Posts: 1,376
    edited 2010-03-09 14:10
    I've noticed that it seems to be (for a reason I can not comprehend) a little "touchy" to make sure the tip of the soldering iron is making good contact with the pad, as well as the wire. I've taken to putting the corner of my small "chisel tip" on the pad. I use a temp of about 630 Degrees F.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    John R.
    Click here to see my Nomad Build Log
  • max72max72 Posts: 1,155
    edited 2010-03-09 14:28
    Thanks, I tried with another protoboard and the problem is less evident.
    The first I tested simply refused the solder. I'll adopt your tips.

    Massimo
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2010-03-09 14:37
    Your cleaned·tip always needs to have a bit of fresh, hot solder there for proper transfer, flow and so on.·

    [noparse][[/noparse]wipe, clean; flash a bit on the tip; apply to connection straight away; flow more solder; remove]

    If your pads are getting contaminated then clean them off by dragging some solder wick across them.
  • max72max72 Posts: 1,155
    edited 2010-03-09 15:00
    What puzzles me is I never had problems, even with dirty, old, oxidized boards. Yesterday at the same time I soldered also the Xbee adapters, with no problems. Only this new, shiny protoboard refused the solder, which kept running away from the pad, climbing the pin of the header.

    Massimo
  • KMyersKMyers Posts: 433
    edited 2010-03-09 18:36
    I just soldered up 2 usb proto boards. It did take me a lot longer then any other board but clean pads is a must along with good solder in the smallest diameter.

    Ken N8SYG
  • hover1hover1 Posts: 1,929
    edited 2010-03-09 19:21
    You might want to clean the board with 91% Isopropyl alcohol with a toothbrush before soldering. For hard to clean boards, I keep a well worn Scothbrite pad around and LIGHTLY hit it with that and the alcohol.

    Jim
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-03-09 21:38
    Pre-cleaning a tinned board should never be necessary. The only time I ever had a problem such as this was with some boards I got from a board house that had a "ghost" of soldermask on the pads (from a screening error, I guess). They were nearly impossible to solder, and the board company eventually relented and redid the job. I'm not suggesting this is the problem with the Parallax board. But you might try scraping one of the pads with an X-acto knife to see if something other than tin plating comes off. Also, these boards have surface mount components on top, which would be impossible to assemble if the top soldermask had an issue. So you might also check to see if components are easier to solder from the top than from the bottom.

    BTW, it might simply come down to the the board fab's use of lead-free solder to tin the pads, so that they're RoHS-compliant. That may entail the use of a higher temperature to solder components to them than you're used to.

    -Phil

    Post Edited (Phil Pilgrim (PhiPi)) : 3/9/2010 9:44:21 PM GMT
  • John R.John R. Posts: 1,376
    edited 2010-03-09 21:44
    I don't think the Prop Proto boards are tinned (RoHS I'm guessing), at least mine are not. The pads do appear to be gold plated. (hmmm, time to scrape off the unused pads and call to get my envelope...)

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    John R.
    Click here to see my Nomad Build Log
  • hover1hover1 Posts: 1,929
    edited 2010-03-09 21:57
    Phil,
    That's kinda of what I was relating to. I have only had it happen·5 or 6 times over the last·20 years.·I know that Parallax has impeccable quality and would never let a sub quality product out of the warehouse. I was thinking of things that happen after the product is opened, spilled liquids, smoke residue, etc.
    Jim
    Phil Pilgrim (PhiPi) said...
    Pre-cleaning a tinned board should never be necessary. The only time I ever had a problem such as this was with some boards I got from a board house that had a "ghost" of soldermask on the pads (from a screening error, I guess).
  • hover1hover1 Posts: 1,929
    edited 2010-03-09 22:16
    The Proto Boards are indeed RoSH compliant. The pads are Copper plated as are all traces.·There is no gold on the board. You have to go back to the 80's to find gold on massed produced boards.

    Jim
    John R. said...
    I don't think the Prop Proto boards are tinned (RoHS I'm guessing), at least mine are not. The pads do appear to be gold plated. (hmmm, time to scrape off the unused pads and call to get my envelope...)

    Post Edited (hover1) : 3/9/2010 10:21:22 PM GMT
  • John R.John R. Posts: 1,376
    edited 2010-03-09 23:08
    Oh well, I guess Steve Wilco will have to wait. smile.gif

    Could the copper on some boards have oxidized? I'm guessing there is some type of coating/treatment to prevent that. Is this possibly an issue?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    John R.
    Click here to see my Nomad Build Log
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-03-09 23:25
    John,

    There's no bare copper to oxidize. All the exposed copper is plated.

    -Phil
  • WBA ConsultingWBA Consulting Posts: 2,935
    edited 2010-03-09 23:38
    Hover1 said...
    You have to go back to the 80's to find gold on massed produced boards.
    Depends on what you mean by "gold plated". Many of the boards we manufacture at work have a finish on them referred to as ENIG, "Electroless Nickel Immersion Gold". The nickel is 150-250u" (micro inches) thick under the gold layer that is 3-8u" thick. Most people would cal it "gold plated" even though "gold plated" in a PCB arena is 30-50u" thick. The nickel layer is to prevent the copper from migrating through the gold. ENIG is commonly called "gold flash" and the thicker gold plating is actually called "plating" or "hard gold".

    My first PCBs for my PowerTwig board were ENIG. My production boards are Tin Lead HASL (hot air solder leveling)

    Merix has a good PDF download on this page showing different surface finish options currently available from them. Has more details on ENIG.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Andrew Williams
    WBA Consulting
    WBA-TH1M Sensirion SHT11 Module
    Special Olympics Polar Bear Plunge, Mar 20, 2010
  • yarisboyyarisboy Posts: 245
    edited 2010-03-10 02:34
    When I worked at the old Gould plant they kept rolls of untreated copper foil refrigerated and it had several months of shelf life. They treated at least one side of most of the copper sold to board laminaters. Two jobs later I worked at Neltec where they would vacuum hot press the laminates others would bond together to make multi-layer boards. There is a right side and a wrong side to put up against the pre-preg before it goes in the heated and evacuated press. Interesting business.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    MOORE'S LAW: The capabilities of electronics shall double every 18 months.
    cloyd's corollary: Hardware is easy, software is hard.
  • max72max72 Posts: 1,155
    edited 2010-03-10 10:34
    The strange thing is the board is brand new, from a recent purchase.
    Both sides are refusing the solder.
    By the way on the bottom there are Parallax soldered pins for DC plug, Xtal, caps and switch, and they look perfect.
    Moreover the other board i received with the same shipment accepted the solder with no problems.

    Massimo
  • LeonLeon Posts: 7,620
    edited 2010-03-10 10:52
    hover1 said...
    The Proto Boards are indeed RoSH compliant. The pads are Copper plated as are all traces. There is no gold on the board. You have to go back to the 80's to find gold on massed produced boards.

    Jim


    John R. said...

    I don't think the Prop Proto boards are tinned (RoHS I'm guessing), at least mine are not. The pads do appear to be gold plated. (hmmm, time to scrape off the unused pads and call to get my envelope...)



    Gold is very common, even on mass-produced boards. It gives better results with lead-free solder paste and the assembly company I use prefers it.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Leon Heller
    Amateur radio callsign: G1HSM
  • Graham StablerGraham Stabler Posts: 2,510
    edited 2010-03-10 21:53
    I find the little circular pads in the prototyping area a bit small, it is quite hard to get good contact with an iron so they can be a pain to solder at times.

    Graham
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-03-10 22:01
    The pads are probably that size to accommodate the Vss copper pour that surrounds each one.

    -Phil
  • Graham StablerGraham Stabler Posts: 2,510
    edited 2010-03-11 00:25
    Very probably, not a criticism just an observation but I wonder how valuable that copper actually is?

    Graham

    edit: vital comma added

    Post Edited (Graham Stabler) : 3/11/2010 12:36:46 AM GMT
  • John AbshierJohn Abshier Posts: 1,116
    edited 2010-03-11 01:16
    $3.41 a pound

    John Abshier
Sign In or Register to comment.