HI Folks
I know, back in the day, we used to have various substances for
solder-masking areas of PCB's - often during flow-soldering.

I've got a need to solder two long (18") 4mm brass 'u'-section strips
together at right-angles - but they need to finish up looking 'brassy'
rather than 'solder-y'.

So - I'm thinking - some sort of 'masking' material - either fluid or tape..
Googling finds something called Kapton tape.. which is a new one on me..

Anybody know anything about suitable materials - only has to withstand
soft-soldering temperatures - but needs to be easily removable so that a
good-looking, polishable brass surface remains..

Thanks
Adrian

On Thu, 21 Aug 2014 17:01:54 +0100, Adrian Brentnall
wrote:

Anybody know anything about suitable materials - only has to withstand
soft-soldering temperatures - but needs to be easily removable so that a
good-looking, polishable brass surface remains..

Kapton (Polyimide Tape) will happily withstand soldering temperatures
and peel off easily afterwards.

In article , Adrian Brentnall
writes
HI Folks
I know, back in the day, we used to have various substances for
solder-masking areas of PCB's - often during flow-soldering.

I've got a need to solder two long (18") 4mm brass 'u'-section strips
together at right-angles - but they need to finish up looking 'brassy'
rather than 'solder-y'.

So - I'm thinking - some sort of 'masking' material - either fluid or tape..
Googling finds something called Kapton tape.. which is a new one on me..

Yes, kapton would be fine, self adhesive and is used for PCB masking.

Anybody know anything about suitable materials - only has to withstand
soft-soldering temperatures - but needs to be easily removable so that a
good-looking, polishable brass surface remains..

High temperature silicone will go to 300degC _once cured_ . If you were
to pvc tape the joint area then smear a thin layer of the silicone then
remove the tape before it sets then I think that would work as a mask.

A little bit steep for a small job though at just over a fiver a tube:

http://www.toolstation.com/shop/p66124

I don't think regular ptfe tape will work as it flux and then solder
will wick under it.

Alternatively, if you are a good solderer then you should have minimal
over tinning and you could buff it off.
--
fred
it's a ba-na-na . . . .

On 21/08/2014 17:01, Adrian Brentnall wrote:
HI Folks
I know, back in the day, we used to have various substances for
solder-masking areas of PCB's - often during flow-soldering.

I've got a need to solder two long (18") 4mm brass 'u'-section strips
together at right-angles - but they need to finish up looking 'brassy'
rather than 'solder-y'.

So - I'm thinking - some sort of 'masking' material - either fluid or
tape..
Googling finds something called Kapton tape.. which is a new one on me..

Anybody know anything about suitable materials - only has to withstand
soft-soldering temperatures - but needs to be easily removable so that a
good-looking, polishable brass surface remains..

Thanks
Adrian

I have it in mind that model-makers have some sort of "paint" for
precisely this problem. Worth googling some more, or try to find a good
model makers' forum (probably US based).

On 21/08/14 17:01, Adrian Brentnall wrote:
I've got a need to solder two long (18") 4mm brass 'u'-section strips
together at right-angles - but they need to finish up looking 'brassy'
rather than 'solder-y'.

you can file surplus solder off, bu t really why not use a hard solder
that looks 'brassy' instead?

Carrs 243

http://www.chronos.ltd.uk/acatalog/E...etc_346. html

this will need a decent flux and a blowlamp, but Id assume that's what
you were up to anyway.

If you are careful with the flux, that will be your solder mask anyway.
The solder wont flow onto un fluxed material


--
Everything you read in newspapers is absolutely true, except for the
rare story of which you happen to have first-hand knowledge. €“ Erwin Knoll

On 21/08/2014 17:40, Peter Parry wrote:
On Thu, 21 Aug 2014 17:01:54 +0100, Adrian Brentnall
wrote:

Anybody know anything about suitable materials - only has to withstand
soft-soldering temperatures - but needs to be easily removable so that a
good-looking, polishable brass surface remains..

Kapton (Polyimide Tape) will happily withstand soldering temperatures
and peel off easily afterwards.

Grand - sounds like the right stuff - thanks!
I may even have found a supplier over here (Ireland)
Thanks
Adrian

On 21/08/2014 17:44, fred wrote:
In article , Adrian Brentnall
writes
HI Folks
I know, back in the day, we used to have various substances for
solder-masking areas of PCB's - often during flow-soldering.

I've got a need to solder two long (18") 4mm brass 'u'-section strips
together at right-angles - but they need to finish up looking 'brassy'
rather than 'solder-y'.

So - I'm thinking - some sort of 'masking' material - either fluid or
tape..
Googling finds something called Kapton tape.. which is a new one on me..

Yes, kapton would be fine, self adhesive and is used for PCB masking.

OK - thanks


Anybody know anything about suitable materials - only has to withstand
soft-soldering temperatures - but needs to be easily removable so that a
good-looking, polishable brass surface remains..

High temperature silicone will go to 300degC _once cured_ . If you were
to pvc tape the joint area then smear a thin layer of the silicone then
remove the tape before it sets then I think that would work as a mask.

A little bit steep for a small job though at just over a fiver a tube:

http://www.toolstation.com/shop/p66124

Hmm - I have some of that from woodburning stove installations..


I don't think regular ptfe tape will work as it flux and then solder
will wick under it.

That would be a problem


Alternatively, if you are a good solderer then you should have minimal
over tinning and you could buff it off.

My soldering's not bad - but the aim is to create a right-angled
'corner' piece, so two sheets of glass can join at 90 degrees.
The 'u' channel is only 4mm x 4mm - so there's not a lot of room for
error... and if I can keep the solder off the outside faces then that'll
make clean-up easier..

I'd normally use standard self-adhesive copper-foil to make the join -
but the client's specified a brass finish, and the thing's going to need
a bit of strength too - so the brass channel and a good strong adhesive
looks favourite..

Thanks
Adrian

On 21/08/2014 17:49, newshound wrote:
On 21/08/2014 17:01, Adrian Brentnall wrote:
HI Folks
I know, back in the day, we used to have various substances for
solder-masking areas of PCB's - often during flow-soldering.

I've got a need to solder two long (18") 4mm brass 'u'-section strips
together at right-angles - but they need to finish up looking 'brassy'
rather than 'solder-y'.

So - I'm thinking - some sort of 'masking' material - either fluid or
tape..
Googling finds something called Kapton tape.. which is a new one on me..

Anybody know anything about suitable materials - only has to withstand
soft-soldering temperatures - but needs to be easily removable so that a
good-looking, polishable brass surface remains..

Thanks
Adrian

I have it in mind that model-makers have some sort of "paint" for
precisely this problem. Worth googling some more, or try to find a good
model makers' forum (probably US based).

Thanks - I did see some mentions of such a substance - but, seeing as
it's a long, straight edge I'm looking to cover, I thought tape might be
the answer ?

Thanks
Adrian

On 21/08/2014 18:53, The Natural Philosopher wrote:
On 21/08/14 17:01, Adrian Brentnall wrote:
I've got a need to solder two long (18") 4mm brass 'u'-section strips
together at right-angles - but they need to finish up looking 'brassy'
rather than 'solder-y'.

you can file surplus solder off, bu t really why not use a hard solder
that looks 'brassy' instead?

Carrs 243

http://www.chronos.ltd.uk/acatalog/E...etc_346. html


this will need a decent flux and a blowlamp, but Id assume that's what
you were up to anyway.

If you are careful with the flux, that will be your solder mask anyway.
The solder wont flow onto un fluxed material


I'm not really set up for 'hard' soldering at the moment -
'soft' will be quite strong enough in this application,
and is possibly less prone to distorting the thin brass channel...

Just looking to minimise the 'cleanup' operations

Thanks
Adrian

"Adrian Brentnall" wrote in message
...

HI Folks
I know, back in the day, we used to have various substances for
solder-masking areas of PCB's - often during flow-soldering.

I've got a need to solder two long (18") 4mm brass 'u'-section strips
together at right-angles - but they need to finish up looking 'brassy'
rather than 'solder-y'.

So - I'm thinking - some sort of 'masking' material - either fluid or
tape..
Googling finds something called Kapton tape.. which is a new one on me..

Anybody know anything about suitable materials - only has to withstand
soft-soldering temperatures - but needs to be easily removable so that a
good-looking, polishable brass surface remains..

Thanks
Adrian


Tippex typewrite correction fluid works well as a solder mask, even up to
silver soldering temperatures

Andrew

In article , Adrian Brentnall
writes
On 21/08/2014 17:44, fred wrote:

High temperature silicone will go to 300degC _once cured_ . If you were
to pvc tape the joint area then smear a thin layer of the silicone then
remove the tape before it sets then I think that would work as a mask.

A little bit steep for a small job though at just over a fiver a tube:

http://www.toolstation.com/shop/p66124

Hmm - I have some of that from woodburning stove installations..

Could be fiddly but might be worth a try. Polyimide (thanks Peter for
the reminder of the proper name) sounds simplest if you find you have to
solder.

Alternatively, if you are a good solderer then you should have minimal
over tinning and you could buff it off.

My soldering's not bad - but the aim is to create a right-angled
'corner' piece, so two sheets of glass can join at 90 degrees.
The 'u' channel is only 4mm x 4mm - so there's not a lot of room for
error... and if I can keep the solder off the outside faces then that'll
make clean-up easier..

Sorry, I was thinking of a flat joint of 2 strips at right angles rather
than what you describe.

--
fred
it's a ba-na-na . . . .

"Adrian Brentnall" wrote in message
...
HI Folks
I know, back in the day, we used to have various substances for
solder-masking areas of PCB's - often during flow-soldering.

I've got a need to solder two long (18") 4mm brass 'u'-section strips
together at right-angles - but they need to finish up looking 'brassy'
rather than 'solder-y'.

So - I'm thinking - some sort of 'masking' material - either fluid or
tape..
Googling finds something called Kapton tape.. which is a new one on me..

Anybody know anything about suitable materials - only has to withstand
soft-soldering temperatures - but needs to be easily removable so that a
good-looking, polishable brass surface remains..

Thanks
Adrian

You can smoke the area with a candle top prevent adhesion.
There was once stuff called plumber's black for the job.
No longer seems to be available.