Practical DIY or modest cost Vapor Phase - does it exist yet?

[kony]

Any update on the possible group buy? I might be open to taking more than 1kg if the price is right.

[spongle]

A tip - I was able to get some "reprocessed" galden in 1kg quantity relatively inexpensively. Look for companies that do reclamation of vacuum oils. Was told the 5kg minimum size is a manfacturer mandate.

[spongle]

Anyone know if I should expect problems using vapor phase for boards with modules?

Will the high heat capacity and vapor defeat metal shields that would protect them during normal reflow?

[rx8pilot]

I finally escaped the grasps for my mechanical engineering responsibilities for a solid run back in EE. So, I can dig back into this topic. Very happy to see the conversation has provided some great information and interest. Now, more than ever, I need the benefits of Vapor Phase for the boards I am making and in some cases repairing.

First step from here is to procure some galden.

[spongle]

I got mine from https://inlandvacuum.com/

Just done a few trials so far with the vegetable steamer method, but it's worked nicely on some connectors that I kept frying with my toaster oven

[Koen]

I've been very happy with vapour and as the last message said, it's brilliant for plastic connectors.

Now, I've recently had issues where parts would jump out of alignment before soldering. Even a massive 7x7 QFN. Would anyone have experienced this ? Could my boards be too close to the liquid Galden ? Could my Galden be too old ? It's been two years. Could it be caused by water mixed in the Galden ? It's weird and I can't really confirm it but it seems to me that there is more liquid in the pot than before.

In the meantime, I'll filter it again tomorrow and see where that gets me.

Thank you ! Koen

[mrpackethead]

I've been very happy with vapour and as the last message said, it's brilliant for plastic connectors.

Its well worth testing though, before you load up an entire board of them.   Some plastics are awesome...   Some.. still melt. 

Now, I've recently had issues where parts would jump out of alignment before soldering. Even a massive 7x7 QFN. Would anyone have experienced this ? Could my boards be too close to the liquid Galden ? Could my Galden be too old ? It's been two years. Could it be caused by water mixed in the Galden ? It's weird and I can't really confirm it but it seems to me that there is more liquid in the pot than before.

That is not an issue i've expereinced.   THe galden i'm using is ~3 years old since i bought the big bottle of it.  I' just top mine up as needed. ( add 50ml or so not that often, i figure i 'loose' about 1 - 1.5mL per cycle.  ).   

Galden is hydroscopic, and so def you will have water in it.  I give my system a cycle before i use it... let the steam escape... it floats out the top, and the galden vapour happioly stays in the bottom.



In the meantime, I'll filter it again tomorrow and see where that gets me.

Thank you ! Koen
[/quote]

[rx8pilot]

Virgin from manufacturer, or used and recycled?
Preliminarily I am interested in 1kg of fresh - but that depends on exact asking price.

I am still looking for experimental amounts, but no luck yet in the USA. 7kg is about $1,000USD.

[spongle]

Did you see my message about https://inlandvacuum.com/ ?

You can also try http://www.synquestlabs.com/product/id/52503.html

[mrpackethead]

Am doing soem work on this today.. :-) Finally..

[rx8pilot]

Did you see my message about https://inlandvacuum.com/ ?

You can also try http://www.synquestlabs.com/product/id/52503.html

I totally missed that, thanks for the repost. Excellent options!

Typet purly on my fone.

[mrpackethead]

Just a bit of useful information for you.  Galden Gas is relatively heavy..  LS230, is about 24kg/m3.   COmpare this to air which is about .7kg/m3.    Thats why it stays in the frying pan if you dont' stir it up.

[Kjelt]

I heard that Galden also evaporates with roomtemperature, very little but enough to keep it in a closed environment.
Can anyone comment or share experiences ?

[mrpackethead]

I heard that Galden also evaporates with roomtemperature, very little but enough to keep it in a closed environment.
Can anyone comment or share experiences ?

I leave my frying pan with the lid on it, between use,  and dont' notice any appreciable loss.   If there is, its minimal.

[Kjelt]

That is good to hear, can you as an experiment when the liquid is roomtemperature, place cellophane (thin plastick) over the pans opening and then the lid on it, and check a week later if there is condensation on the inside ?

[mrpackethead]

That is good to hear, can you as an experiment when the liquid is roomtemperature, place cellophane (thin plastick) over the pans opening and then the lid on it, and check a week later if there is condensation on the inside ?

I could' but i'm not going to.  I have a glass lid on my pan, ( it is curved, so if there was any significiant moisture, it would roll back to the pan ).. and i've not seen any significant condenstation on it.   

The biggest issue is that the Galden is quite hydroscopic, and the first time you heat cycle it, after its been sitting for a while you will often end up driving a bit of steam out.. ( which is easy to confuse for it being 'galden vapour'.   If i've not used my pan for a few days, i'll give it a cycle first, the water is driven of.

[Lukas05]

Hi everyone,

I´ve been following this thread with great interest. Very useful information hidden in here 
It seems that some of you had a similar issue as myself. I´ve soldered my PCBs with my hot air station for many years now. The molten plastic base of SMD electrolytic capacitors where the ugly result 
For my current project this was no longer an option. Unfortunately there was no cheap solution at an acceptable price or quality (China chip heater haven't worked too well  )

This situation motivated me to work on my own vapor phase oven design. Since I´ve learnt a lot in this thread I thought I should share the progress of the project.
The construction is actually quiet simple:
An old stainless steel pot from a gastronomy auction is used as the process containment. I´ve used GPU watercooling blocks on each side of the container, to cool the inner walls at a height of about 15cm above the liquid. Two 120mm radiators keep the water cooling loop at about 5K above ambient. A perforated aluminum sheet is suspendet on four steel wires, wich are fed through a stiff tube to the actual "lift".
By varying the hight of the aluminum sheet it is possible to realise a solder profile.
The cover of the container ist liftet by rolling up some steel wire wich is connected to the suspension of the cover. This way I´am able to lift out the finised PCBs whithout running the risk of burning myself.

The first results don´t look too bad in my option. The solder stencil needs some tweaking considering the aperature size. Also the solder profile needs to be implemented properly for shiny solder joints.
This is just the current prototype... The wiring will be cleaned up when the controller board is finished. I´m also planning on some nice stainless steel sheets tho cover up the whole apparatus. Next step would be to implement the software and a fancy color lcd 

https://www.flickr.com/photos/136915492@N02/49030571321/in/dateposted/

https://www.flickr.com/photos/136915492@N02/49030571011/in/photostream/

https://www.flickr.com/photos/136915492@N02/49030789407/in/photostream/

https://www.flickr.com/photos/136915492@N02/49030789177/in/photostream/

https://youtu.be/Du0YXhiLl0w

[rx8pilot]

This is just the current prototype... The wiring will be cleaned up when the controller board is finished. I´m also planning on some nice stainless steel sheets tho cover up the whole apparatus. Next step would be to implement the software and a fancy color lcd 

That is awesome! 

[mrpackethead]

Ok, that is seriously cool.  Sorry lots of questions.

What is providing the heating?
How deep is that container, and is that the lid that came with it, or something else.
Whats pulling the steel wires?

Are you dropping the temp of the galden before you open the lid?

[Kjelt]

Nice build Lukas  Very impressive.

If you have to do serious production you could opt for an active watercooler that keeps the temperature at a set point. They are not that expensive ($300) mostly used for CO2 laser tube cooling and you can use carcoolant instead of water to keep it a closed system and prevent corrosion.

[Lukas05]

Hi all, I´m glad you like my approach to the problem so far 

What is providing the heating?

I´m using a 1100W heating element from a small tabletop oven. This form factor fits quiet nicely in the bottom of the container.
The big aluminum chunk in the middle is there to displace some of the galden. This way I only need 200ml of liquid wich benefits the BOM cost of the system 
The specific heat of aluminium is also lower than that of galden, wich means the big block doesn´t adversely effect the thermal impedance of the system. (excluding the limited surface and lack of convection)

How deep is that container, and is that the lid that came with it, or something else.

The container is about 35cm deep. The lid is the one that came with it. I just cut out the opening for the window, an added a gasket around the lid.

Whats pulling the steel wires?

The steel wires for the inner lift are attached to a spindle driven actuator.
Behind the spindle you can see the roll up mechanism for the lid lift.

Are you dropping the temp of the galden before you open the lid?

Yes, I drop the galden temperature to about 80°C. One design goal is to loose as little galden as possibile. I use four fans under the container that ramp up once the solder process is finished, and the inner lift is in it´s final position under the lid. Due to the relatively small combined mass of the galden an the aluminium block (and the high temperature difference) this is enough to cool the system down to 80°C in about 3-4 minutes.
Since the PCB inside just looses heat through convection (and a minor part due to radiation) it stays slightly above the gas temperature directly under the lid. This way the galden won´t condense on the PCB, and I get a dry board after soldering and cooling.

If you have to do serious production you could opt for an active watercooler that keeps the temperature at a set point. They are not that expensive ($300) mostly used for CO2 laser tube cooling and you can use carcoolant instead of water to keep it a closed system and prevent corrosion.

I´ve thought about active cooling. At this point though since I´m only using this for prototypes I don´t see the need to. But I will definitely switch the water out for something more corrosion inhibiting.
But even before that I have to get the brass pipe fitting out of the water tank. Copper alloy, aluminum water blocks, and plenty of electrolyte won´t go well for very long

[mrpackethead]

You've done somethign very clever there.

The container is really interesting, iv'e looked all over for a container that deep, and just can't find one.

[JPlocher]

Would something like a 20q/l roasting oven be a useful starting place?    At $US 50, they won't break the bank...

example: https://www.walmart.com/ip/Hamilton-Beach-28-lb-Turkey-Roaster-Oven-Model-32231/54056097

  -John

[ignilux]

Damnit you guys, the last thing I needed was another cool thing to spend money on. And yet... I must have one!

[Kjelt]

Would something like a 20q/l roasting oven be a useful starting place? 

too shallow unless you are willing to loose Galden, which is much more expensive than that oven.