Vapour phase reflow?

[SteveW]

Gopher mentioned vapour phase in another thread - I thought it was dead & buried when CFCs got banned, but I've obviously not been paying attention.
It does sound like a good candidate for me - always small batches, always an odd mix of components, and space limited.
Does anyone here have experience?
http://www.blundell.co.uk/detail.php?id=IBL-SV260&mnuCategory=vapour%20phase%20soldering&form=4&StartLoop=0
http://www.ibl-loettechnik.de/englisch/products_sv260.html  - luxury
http://www.ibl-loettechnik.de/englisch/products_minilab.html -tiddler

Both seem convinced it's a really cheap process to buy & run, which also has an appeal... But it'll still be a substantial investment for me, however cheap they think it is, and my OK batch oven, crappy as it is, does currently do the job.

Does the fluid crud up with flux? Do the boards smell funny? How much precious fluid vanishes per use? Does the surrounding area end up with a thin layer of some freaky fluorofluid? Do any components hilariously dissolve in the stuff? (LEDs with clear lenses, f'rinstance?) Looking for the pitfalls that the manufacturers may only mention when pressed.

Ah, dammit - a search for 'homebrew vapour phase' finds
http://forums.adafruit.com/viewtopic.php?f=42&t=16085
where our hallowed forum owner asks many of the same questions

Steve

[Gopher]

I have no experience of it but it is something that does seem to be being pushed again. Because of that and because on paper at least it has lots of advantages I have asked a few questions, of sellers
Q)How do customers handle double sided boards?
A)DIY standoffs from pcb's cutoff's or similar

Q)How much fluid gets used?
A)1g/cycle according to the datasheet I have for a Roland Hecht

Q)What Does The Fluid Cost?
A)£100-£150 /Kg depending on the phase temp your want and no doubt how much you buy.

Q)Are there problems with contamination?
A)You do eventually have to change the fluid, depending on what your are placing you may have to change your paste to match. If there are other contaminants in your process that's a different and bigger issue and would apply to other processes too. (For instance

Q)Led's?
A)No Problems.

Q)What does finished product look like?
A)Very Clean, no discoloured parts etc as one might get from Reflow without NO2.

Q)What about in-line?
A)Stupidly expensive! inline vapour phase systems have expensive cooling & circulation systems this is perhaps the biggest reason they have not caught on to the extent the hype would suggest they should have.

Q)Who has suggested VP to me?
A)David Clements, Europlacer and MyData, Two of these people don't sell them, though VSMT may have been dabbling at the time. MyData have Asscon? VP ovens as part of their demo line and say quite a few of their customers buy the line as they see it. YouTube based promo videos of sold lines would seem back this up.

Q)Cycle Time?
A)~6mins

On the whole most people selling equipment have been very approachable and good at answering questions, for our purposes however VP appears not to be the preferred option as for throughput Forced Air Convection wins out by being cheaper to invest in.

[Ed]

i know a chap who has been running a small one for 2 years now. he is still on his 1st 5kg of fluid and runs most days.. IBL are the best and with lowest running cost.

[trev]

I know this is an old thread but felt better to reply to this than start a new one on the same subject. Anyone had any success with homebrew vapour phase ovens? I have not found any reliable plans for building one yet. It looks interesting but I do not want to spend weeks trying to build something and experiement with it trying to get it to work. I would just like to build something and maybe spend a weekend getting something working. 

Trev

[Mike]

Pretty sure I've  seen something about using domestic fryers.
Here's a thread on EEVBLOG about it
https://www.eevblog.com/forum/projects/vapour-phase-soldering/

[trev]

Hi Mike, do you have any thoughts on vapour phase homebrew ?

[Mike]

Not really - an issue may be buying fluid in a sensibly small quantity, and need for a suitable sized container.
Toaster oven works fine for me, but I don't use leadfree

[trev]

What I currently do not know is how to control the rate  at which vapour phase heats a board. Does it just self regulate in that way? Is it really as easy as heating the solution and waiting for the solder to flow? Seems you have to know when it's done because a board can not stay hot for too long 

[Mike]

The idea AIUI is that the vapour has a constant temperature, so you just need to figure out the time to put the board in for, but it can never overshoot due to the characteristics of the fluid.

[trev]

Am thinking more about how quickly a board would heat up and then knowing how long the board is at 230C for. I do not see any  temperature sensors on boards like with oven based ideas.

[trev]

Well looks like I just sourced some LS 230 so I can do some testing. I think thermocouple tests on a board should provide all the information required. I just need to source the right type or container. The fat fryer type with the cage look good to me. Need a bit of a seal around the lid maybe and possibly a grid at the top connected to a peltier to create a cold layer at the top.

[trev]

https://youtu.be/OFJVdk_T7is

Looks pretty straight forward

[trev]

This is a better video...same person 

https://youtu.be/czwRntpEzgg