Dangerous Prototypes Open Source Hardware

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #30 – July 03, 2011, 05:15:56 pm

Seeed started carrying them too, just saw it today but they are sold out.

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #31 – July 03, 2011, 07:38:48 pm

I understood that this lot lacquer don't bond with PP (and does bond with thermal foil one would regularly use to print with laser printer on) ... have anyone tried paper? can you use tracing paper directly on the ink or you still need to add a layer of PP foil between?

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #32 – July 03, 2011, 08:02:39 pm

If it's porous, it bonds to it. It's quite liquid and actually wets paper. Maybe waxed paper doesn't bond, but I haven't tested. It bonds to lots of materials, including glass, aluminium, copper and some plastics that I said before. It doesn't bond to polycarbonate, polyethylene (low density) and polypropylene as far as I've tested.. I think that for some reason it just bonds to polyamides and polyesters

I've seen that seeed also uses an intermediate layer of plastic on its tutorial.

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #33 – July 03, 2011, 08:57:31 pm

PP and PE are nasty :) not many things bonds to them :D ..

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #34 – July 08, 2011, 08:40:04 am

[quote author="arhi"]The tip for the tinner - you get a multi part one. The shelf life is many years (of the parts). Then you mix only small amount (100cc for e.g.). The shelf life of the mixture is bit over 6 months (even after a year it works but too slow). after 6 months you throw those 100cc and make a new batch, thats many years of service for 20E :D[/quote]

I am really interested in this multi part tinning agent.

As a homebrew PCB maker, I use tinning agents not very frequently and expect something that would last me 5 years without shelling hundreds of dollars.

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #35 – July 08, 2011, 09:16:11 am

check your local electronics store, most of them sell one or another multi part chemical tinner ..

the pre mixed solution has a shelf life between 6 months and a year and are fairly cheap, there is also "extended shelf life" version with up to 5 years shelf life (I never tried those so ..)

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #36 – July 08, 2011, 09:22:37 am

[quote author="arhi"]check your local electronics store, most of them sell one or another multi part chemical tinner ..
[/quote]

Sure, but I would like to know which ones you use and recommend.

[quote author="arhi"]
the pre mixed solution has a shelf life between 6 months and a year and are fairly cheap, there is also "extended shelf life" version with up to 5 years shelf life (I never tried those so ..)[/quote]

I saw the MG Chemical bottle. Stores near me have it, but the shelf life of a year at best is a bummer - I don't use that much!

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #37 – July 08, 2011, 10:08:43 am

[quote author="KamalS"]
Sure, but I would like to know which ones you use and recommend.
[/quote]

I use SUR-TIN because it is the only multi part available in local store and I am super satisfied, basically because while in "non mixed" state the parts have super long shell life. Now if you mix all parts together you get 2.5L of stuff that will stop working in 6 months, but you don't mix it all up. What I do is I split all 3 parts in 4 measurements. I just approximate it I don't use some fine scale etc. So you mix in 1/4 of the liquid and 1/4 of the first powdery thing and 1/4 of the second salty thing with 625 (600 is fine :D ) mL of water. You can use regular tap water but if you can use demineralized / distilled water you will improve shelf life of newly made tinning solution. This 600mL of solution will last you some 6 months (or 0.5m2 of tinned copper whatever comes first).

I personally use this 600mL until it stops working, then I throw it away. I know some ppl who don't ever throw it away but just add a second batch of chemicals into same solution and top it with distilled water up to 650mL .. but I never tried that so can't say if it works better or worse then new solution..

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #38 – July 08, 2011, 10:19:11 am

[quote author="arhi"]
I use SUR-TIN because it is the only multi part available in local store and I am super satisfied, basically because while in "non mixed" state the parts have super long shell life[/quote]

Ah! I have watched many a video of Bungard Sur Tin :-)

Shipping it would kill the deal unless there is something similar here in SoCalifornia.

All I see here are those tinning liquids - nothing solid that I could use a bit now and then :-(

Would love to stand corrected!

Re: Soldermask ink for homemade PCB's (yeh, the green stuff)

Reply #39 – July 08, 2011, 10:46:55 am

Check out the prices of those liquids .. maybe they are useful too ... for e.g. those "long shelf life" ones claim to have 5 years shelf life.. that should be perfect solution, also check the package sizes.. I seen in Hungary some liquid tinning solutions (the box only said "chemical tinning solution" - no "brand") my friend uses and they come in 500mL packs for cca 5eur and last almost a year .. that would be more then ok solution imho ..