Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

previous by date index next by date
previous in topic topic list next in topic

Subject: Re: Solder Mask

From: "storan4wd" <bob.balderson@...>
Date: 2012-02-21

Hi Terry,

I have just ordered a metre of Dynamask
<http://www.octamex.de/shop/?page=shop/flypage&product_id=31&category_id\
=5848924494118370762daa6f026e22f7&/Dynamask__Loetstopplaminat_1m_kaufen.\
html> to play with. It's certainly not as cheap as green goop but if
it means less faffing time and more repeatable results it will be a
better solution for me. Stay tuned!

Regards,

Bob

--- In Homebrew_PCBs@yahoogroups.com, "Terry" <twgray2007@...> wrote:
>
> True that it is a bit expensive on a per ounce basis, but with the
volumes necessary for purchase for the 'real stuff' it is not bad...and
this is one of the best means of applying soldermask to a homebrew board
that I have found. I've tried every method that I could think of, or
find on Google, and never came up with anything that gave results even
close to this. I even went so far at to buy the 'real stuff', which was
epoxy based, had to be mixed prior to use, had a very short (1 week)
shelf life after mixing, and required a minumum purchase of a 5 gallon
bucket of developer. Total cost about $250. The stuff from China was
about $6.00 - $7.00 per tube, had a long shelf life, and I could make
several boards with a single tube.
>
> Does anyone have a better solution?
>
> --- In Homebrew_PCBs@yahoogroups.com, Simao Cardoso <simaocardoso@>
wrote:
> >
> > storan4wd wrote:
> > >
> > > I think the real lesson I've learned is that the mask is designed
for
> > > stencil printing only; quick drying isn't a priority as it's not
> > > intended to have anything in contact with it when curing.
> >
> > As a side note, did you ever consider that such cheap eBay stuff,
sold
> > from china, is not even similar to real soldermask?
> >
> > It must be repackaged stuff, the eBay seller can say what he wants
with
> > his package. I don't know to read chinese, but to see what it really
is
> > you could try google goggles from a camera phone and translate, if
you
> > have the real manufacture package. EBay sellers say it's uv curing
ink,
> > but it can just be UV curing EPOXY GLUE.
> >
> > But if you look to one more expensive seller (the one who started to
> > sell the stuff as soldermask) he has a working method, see item
> > 260937497342. He lays a bit of it at pcb center and spread it with
the
> > mask directly. Expose for some time and them it should require extra
> > curing after solvent washing. A couple of years ago i asked him a
msds
> > or that he just say what could be used as thinner for it. His
answer:
> > 'this is just chinese crap, no msds/documentation was ever written'.
> >
> > You should know that real LPI soldermask is half the money by
quantity
> > compared to that stuff.
> >
> > BTW (and off topic) Does anyone ∗really∗ know what PM or PMA solvent
> > is???? I must know (and be sure) to use with real soldermask... :/
> >
>

--- In Homebrew_PCBs@yahoogroups.com, "Terry" <twgray2007@...> wrote:
>
> True that it is a bit expensive on a per ounce basis, but with the
volumes necessary for purchase for the 'real stuff' it is not bad...and
this is one of the best means of applying soldermask to a homebrew board
that I have found. I've tried every method that I could think of, or
find on Google, and never came up with anything that gave results even
close to this. I even went so far at to buy the 'real stuff', which was
epoxy based, had to be mixed prior to use, had a very short (1 week)
shelf life after mixing, and required a minumum purchase of a 5 gallon
bucket of developer. Total cost about $250. The stuff from China was
about $6.00 - $7.00 per tube, had a long shelf life, and I could make
several boards with a single tube.
>
> Does anyone have a better solution?
>
> --- In Homebrew_PCBs@yahoogroups.com, Simao Cardoso simaocardoso@
wrote:
> >
> > storan4wd wrote:
> > >
> > > I think the real lesson I've learned is that the mask is designed
for
> > > stencil printing only; quick drying isn't a priority as it's not
> > > intended to have anything in contact with it when curing.
> >
> > As a side note, did you ever consider that such cheap eBay stuff,
sold
> > from china, is not even similar to real soldermask?
> >
> > It must be repackaged stuff, the eBay seller can say what he wants
with
> > his package. I don't know to read chinese, but to see what it really
is
> > you could try google goggles from a camera phone and translate, if
you
> > have the real manufacture package. EBay sellers say it's uv curing
ink,
> > but it can just be UV curing EPOXY GLUE.
> >
> > But if you look to one more expensive seller (the one who started to
> > sell the stuff as soldermask) he has a working method, see item
> > 260937497342. He lays a bit of it at pcb center and spread it with
the
> > mask directly. Expose for some time and them it should require extra
> > curing after solvent washing. A couple of years ago i asked him a
msds
> > or that he just say what could be used as thinner for it. His
answer:
> > 'this is just chinese crap, no msds/documentation was ever written'.
> >
> > You should know that real LPI soldermask is half the money by
quantity
> > compared to that stuff.
> >
> > BTW (and off topic) Does anyone ∗really∗ know what PM or PMA solvent
> > is???? I must know (and be sure) to use with real soldermask... :/
> >
>



[Non-text portions of this message have been removed]