Connect with us

Hot Air station from Harbor Freight Plastic welder??

Discussion in 'Electronic Design' started by James Lerch, Aug 3, 2007.

  1. James Lerch

    James Lerch Guest

    Might it be possible to fabricate a simple hot air re-work station
    from a harbor freight plastic welding "machine"?

    Here's the item in question (which I recieved as a gift and have no
    use for).
    http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=41592

    Thinking that it's pretty much a hot air station already, would it be
    feasable to:

    Add Thermocouple, adjustable diaghpram pump, and Pic controller to
    create a semi usable Hot Air re-work station?

    Mostly, I'm just looking to de-soldier larger SMD chips, and also can
    you have too many intersting projects?? :)

    If the answer is "yes, maybe" and since I've never held a hot air
    soldiering iron:

    How accurate must the output air temp be?

    Exactly what temp range should I anticipate?

    How much air flow?

    Any ideas (other than the obvious "go buy a real one")

    And no, my income does not depend on this device, its strictly a
    method of killing time and money.. :)
    --
    Take Care,
    James Lerch
    http://lerch.no-ip.com/atm (My telescope construction,testing, and coating site)
    http://lerch.no-ip.com/ChangFa_Gen (My 15KW generator project)

    "Anything that can happen, will happen" -Stephen Pollock from:
    "Particle Physics for Non-Physicists: A Tour of the Microcosmos"

    " Press on: nothing in the world can take the place of perseverance.
    Talent will not; nothing is more common than unsuccessful men with talent.
    Genius will not; unrewarded genius is almost a proverb.
    Education will not; the world is full of educated derelicts.
    Persistence and determination alone are omnipotent. "
     
  2. GregS

    GregS Guest

    Trying to compare my Weller WRS3000.
    I have to use the lowest air flow of 10. 10 what I would have to look
    up, but its very small amount. I have to jack temp up to
    max usually to close to 1000 degrees to melt solder. I have not done much or
    had any success with this pen. I mostly use it to clean off boards
    and it prevents moisture build up when i blow off alcohol, but the fine tips
    controls the pattern so I have even melted glue sticks, or made some
    of my hot melt jobs pretty.

    greg
     
  3. GregS

    GregS Guest

    I might get one of those HF units for other uses. I am also going to check if
    they have the resistor assortment case in the store.

    greg
     
  4. Joerg

    Joerg Guest

    Last time I looked they only had the flat boxes. We bought them anyhow
    because we urgently needed somthing at that client (start-up, basically
    didn't have an electronics lab at that time).
     

  5. http://www.harborfreight.com/manuals/41000-41999/41592.pdf


    --
    Service to my country? Been there, Done that, and I've got my DD214 to
    prove it.
    Member of DAV #85.

    Michael A. Terrell
    Central Florida
     
  6. Benj

    Benj Guest

    I think the answer is yes, maybe! I like this idea. I think I'm going
    to buy one of these to play with! My experience is that a single hot
    air pencil like this is not going to be too cool for SMD rework. The
    usual station with solder sucker and hot air is useful to a point but
    to REALLY suck the big chips off you have to heat ALL the leads at
    once. Going round and round with a pencil won't cut it.

    But there are possibilities here! The way you'd use this on a small
    chip would be to first suck the excess solder off the leads and then
    use hot air to lift the leads on one side and then the other. When
    there are leads all the way around, however, you need to heat them all
    at once.

    You might do that mounting 4 hot air pencils together or building a
    manifold to direct the hot air. The big machines I've used to remove
    SMDs had a pot load of manifolds in different shapes each to direct
    the air onto the leads of a given chip style. Usually a square tube
    surrounded by another square tube of a larger size where the hot air
    came down on the leads between the two tubes. To lift the SMD there
    was a silicone rubber suction cup activated with an air vacuum that
    sucked onto the top of the chip and supplied an upward force to lift
    it when the legs all melted. Totally effective. Totally slick! And Oh
    yeah, TOTALLY expensive!

    I have been long wanting to put together a cheap homebrew version of
    one of these devices. And you've opened some real possibilities with
    this plastic welder thingie.

    Yeah, may take some adapting, but I'm optimistic. In my experience air
    flow and temperature control isn't really all that critical so long as
    you keep in in a decent range to melt solder and remove the heat as
    soon as the part desolders. I think you are onto something here.

    Benj
     
  7. LVMarc

    LVMarc Guest

    The temp and airflow would enable you to reflow the paste flow to build
    widgets and to soften large areas and non destructively remove as well!
    lloks like a winner! Not clear on one thing.. does it make itown air
    flow or do yu need a tank or compressed air supply. please have orogianl
    poster confirm whter it blows own air!

    marc
     
  8. Ecnerwal

    Ecnerwal Guest

    I suppose you could, but places like MPJA (just a customer, and that was
    perhaps 10 years ago) have actual (if presumably somewhat cheesy, given
    the price - but you're looking at HF, the definition of cheesy) hot air
    rework stations for $100, so spending $40 for this and then adding a
    pump (since it needs an air supply), etc. will probably cost you more.
    They include several nozzles, and have other nozzles available to fit
    various packages.

    I've been doing a bit of SMD rework with an iron - no 4-sided packages -
    just 0805s and SIPs. Desoldering actually impairs the process (with an
    iron) - with a good bit of solder everything can get fluid and the part
    can be moved - desoldering first makes it difficult to get the part hot
    (lousy contact) and causes it to cool off more quickly, so it sticks.
    Even with air, I'd expect desoldering to be irrelevant if the part can
    be heated all around.

    I have been contemplating a hot air setup myself. If cooking it up as a
    project is the aim, why not seek out old/junk hair-dryers or toasters as
    cheap/free sources of nichrome wire and really roll your own - if buying
    parts, I'd expect that buying the $100 version would be cheaper as well
    as faster.
     
  9. Joerg

    Joerg Guest

    Looks like it needs to be connected to an air system. I guess they
    assume that a real man's garage will contain the biggest honking
    compressor the neighborhood has seen. Red, at least a 5ft tall tank, and
    loud.
     
  10. Rich Webb

    Rich Webb Guest

    Other places (been looking for a "home unit" myself) to check are
    http://www.howardelectronics.com/ (lots of Xytronic gear)
    https://store.sra-solder.com/ (Aoyue)
    http://www.web-tronics.com aka www.circuitspecialists.com (Xytronic
    and rebranded Aoyue)
    Pick up some Chip Quik. Worked like a dream for me on a 48 pin TQFP
    (0.5 mm pitch) with just an iron and good ol' Kester #44 paste. Even
    though it's relatively expensive stuff (US$8-ish per foot) it may be
    the way to go for onesie-twosie usage.
     
  11. James Lerch

    James Lerch Guest

    Yea, but mines older than I am :)

    In any event, yes it needs an air pump. The original device came with
    a cheap (surprise) pressure regulator used to adjust the output air
    temp.

    I'm thinking that I can rig one of the cheap fish-tank based diapharm
    pumps and regulate air flow with electronic circuit (as opposed to
    plugging air pump into wall outlet).

    Once air flow can be electronicly regulated, I just need thermocouple
    and some type of SSR based temp controll circuit.

    BTW, I almost purchased a real hot air stating, but looking at it (and
    already owning the useless harbor freight plastic welder) I figured
    what the heck? It's only going to get used to make projects, why not
    make a project out of the hot air gun :)
    --
    Take Care,
    James Lerch
    http://lerch.no-ip.com/atm (My telescope construction,testing, and coating site)
    http://lerch.no-ip.com/ChangFa_Gen (My 15KW generator project)

    "Anything that can happen, will happen" -Stephen Pollock from:
    "Particle Physics for Non-Physicists: A Tour of the Microcosmos"

    " Press on: nothing in the world can take the place of perseverance.
    Talent will not; nothing is more common than unsuccessful men with talent.
    Genius will not; unrewarded genius is almost a proverb.
    Education will not; the world is full of educated derelicts.
    Persistence and determination alone are omnipotent. "
     
  12. Yes, of course! But not the wimpy noisy oilless type, a real man uses
    a (relatively) quiet 5HP or better, 240VAC two-stage oil compressor.
    I'm still smarting that I missed the local HD sale of a new display
    model 80-gallon Ingersoll Rand at 1/2 price. Far better than those
    $500 Sam's Club specials.

    Of course the real man had better drain the tank regularly, or a photo
    of his house and what's left of him might show up in the local news
    when the tank finally rusts through-- there's a heck of a lot of
    energy stored in those tanks. I'm waiting to hear about injuries from
    all the cheap offshore $100 ones (including a nailer) being sold. I
    bet most people don't bother reading the manual. There's still enough
    energy in the little tanks to cause injury.



    Best regards,
    Spehro Pefhany
     
  13. Glen Walpert

    Glen Walpert Guest

    Of course real men keep their compressors in the workshop not the
    garage, and they have an automatic drain valve installed on the big
    one :).

    While even small compressor tanks store a fair bit of energy I have
    never heard of an injury caused by the fairly frequent occurrence of
    rust out. If the tanks are made to the applicable parts of the ASME
    pressure vessel code then the material is a relatively low strength,
    highly ductile steel not prone to brittle fracture. The usual failure
    starts out as a slow leak which will increase gradually until noticed.

    Of course you may not have a lot of reason to assume that Chinese
    compressor tanks conform to code if you use the historical code
    conformance of other Chinese products as an indicator!

    For the hot air soldering application a nitrogen tank with regulator
    would be the way to go for lead free. For regular old fashioned
    tin-lead I prefer a system based on a small centrifigual blower at
    lower pressure and higher flow rates than used by small hot air
    plastic welders. But the HF plastic welder should work fine within
    its size limitations if used appropriatly (preheat is essential, plop
    your board down on a pancake griddle for instance) and adequate
    temperature regulation should be possible with just an air pressure
    regulator and a variac or light dimmer, given some means of temp
    measurement.
     
  14. Guest

    Hi

    Why on earth will I want to create such a crude device for soldering smt
    just go and pick up
    a cheap copy of hakko 850 and get heads that fit smd packages so that you
    do not blow
    surrounding cap off the board.

    www.sra-solder.com sells
    Aoyue 850A++ SMD Hot Air Rework Station at 100us and all the hakko nozzels
    fit the system

    look also at the nozzels

    https://store.sra-solder.com/section.php?xSec=52

    Try use the
    http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=41592
    as paint stripper.

    Arie
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-