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What's wrong with my first batch of Pripp's Flux


#1

Hello,

New to the forum, but hoping someone can help… My head started
spinning around page 15 of the archived posts about pripps, so
forgive me if this problem has already been addressed!!

I’ve just mixed up my first batch of Pripp’s Flux following the
instructions in Tim McCeight’s the “Complete Metalsmith”, but the
solution has gone all lumpy since it has cooled… Any suggestions on
where I may have gone wrong?!?

Many thanks in advance,
regards
Emma


#2
I've just mixed up my first batch of Pripp's Flux following the
instructions in Tim McCeight's the "Complete Metalsmith", but the
solution has gone all lumpy since it has cooled... Any suggestions
on where I may have gone wrong?!? 

Shake it up, it should be fine


#3
where I may have gone wrong?!? 

Just add more water.

Prips (which is spelled with ONE “P” at the end, not two. It’s named
after the late John Prip, who introduced it to U.S. silversmiths) is
a mix of 3 parts boric acid to 2 parts each, borax and sodium
phosphate. Dissoved in enough water to keep in dissolved. If you’re
getting lumps crystalizing back out as it cools, just add enough
water to redissolve it. Tap water is fine.

Notes:

I’d normally start with quantities of 96 grams of boric acid, and 64
grams of both the others to a quart of water. Sometimes it needs
little more water if I’m not so careful weighing the stuff. There’s
no harm in making it more dilute. Much more dilute if you like. It
just means you have to spray more flux on to get a good coat on the
metal.

It DOES have to be sprayed for best results. You can sort of use a
brush, but this doesn’t work so well. The best sprayer I’ve found is
a mouth blown atomizer intended for ceramics glazes. It’s simply two
tubes and a hinge. Simple, and doesn’t clog the way many trigger
sprayers will do.

It’s critical to make sure that the sodium phosphate you use
actually IS sodium phosphate. You can actually find three forms of
this. Theres monosodium phosphate, disodium phosphate, and trisodium
phosphate, commonly referred to as “TSP”. The last is the most
commonly used and found, and usually cheapest. But all three will
work. The problem arises in that TSP, which has long been used as a
fairly strong alkaline cleaning agent, being a phosphate, presents
pollution problems in waste water streams. So at least in the U.S.,
many locations have banned or discouraged it’s routine sale. Sold
instead, are sodium silicate based cleaners, or other cleaning
agents, which often are labeled with confusingly similar names, since
they’re marketed for the same “pre-painting, wall washing” sorts of
tasks TSP used to be recommended for. The trick is to make sure
you’ve actually got TSP, not some other chemical, since those others
won’t work.

However, at least in the U.S., you can use “Cascade”, a common brand
of dishwashing machine powdered detergent. This stuff too is made in
phosphate free formulas in some places, and these don’t work. But the
green box version which lists a phosphate content, DOES work in place
of plain TSP, with the formula to mix it otherwise the same. This
alternative chemical was suggested by Fred Fenster, so the flux gets
then called “Frips”. I don’t know if this is available in the UK, but
if you’re moved to do so, you could always research similar products
sold there…

Peter Rowe


#4

The Pripps?" recipe" mixed warm makes a saturated solution which will
crystallize out as it cools and or loses water to evaporation. This
can clog spray systems. Heat it up and shake or stir to re dissolve
or add a bit more water.

jesse


#5

Many thanks Peter and Jesse for your replies. I’ll add more water
and see if it helps!!

Prips (which is spelled with ONE "P" at the end, not two. 

I guess I got carried away with my “p’s”, Pripps sounds awfully
British, you know!! he he ;o)

It DOES have to be sprayed for best results. The best sprayer I've
found is a mouth blown atomizer intended for ceramics glazes. It's
simply two tubes and a hinge. 

I think I still have one of these from my art school days, will have
to hunt for it in the scary attic, if I don’t post again send out the
search party…

It's critical to make sure that the sodium phosphate you use
actually IS sodium phosphate. 

Now for the science bit, I’ve managed to locate a source of
industrial/technical grade, high purity TSP off eBay in the UK, (from
XDISCS, if any one is interested) what I was actually trying to
source was Sodium Acid Phosphate to make an FM Solution, does anyone
know if TSP could be used as a substitute?

Best regards
Emma


#6

You have to use regent TSP.

Lloyd


#7
Shake it up, it should be fine 

Thanks Steve, I’ve added more water, and now only have a tiny bit of
sediment which dissolves upon shaking… Though it does remind me of
cloudy lemonade!!

I have up a batch of FM to make up but never tried it - I don't
know any one who has. 

Jesse, I was introduced to FM solution by my tutor Sarah Macrae at
West Dean College, it is the best firestain inhibitor/flux I’ve used
so far… It can be sprayed or painted on warmed metal to form a
protective skin, or effectively applied to cold metal when annealing
and soldering, which is great when you are a beginner! But having
trouble tracking down the chemicals used in it, I was looking for
alternatives, which is why I’m trying out the Prips… but I’ll
certainly give it a go with the TSP as an alternative to Sodium Acid
Phosphate and see how it goes, I’ll report back if I end up looking
like Beaker from the Muppets!!

Emma


#8
You have to use regent TSP. 

No, not really. You have to use actual TSP. But the stuff from
hardware stores sold for cleaning walls before painting, if you can
find it, works just fine. High purity isn’t needed. Plain old
technical or commercial quality is enough. I’ve made batches of Prips
with TSP and other ingredients from both “grocery store” quality and
"chem supply" lab grade quality. I’ve never found any difference in
performance.

Peter


#9
I was introduced to FM solution by my tutor Sarah Macrae at West
Dean College, it is the best firestain inhibitor/flux I've used so
far... 

Ok, so that’s a new one for me, for a change. What is FM? What’s in
it? I’m assuming from your post you mix this up yourself, like Prips.
What’s the recipe please?

Peter


#10

that’s not unusual- it crystallizes in hot weather and with
evaporation- add some distilled water, shake it up and it will work
well…rer


#11

Hello Peter

FM Solution was originally taken from a seminar report run by the
Worshipful Company of Goldsmiths way back in the 1970’s, part of
this team included Jeanne Werge-Hartley who so happens to be Sarah
Macrae’s mother… I was lucky to nab a bottle from Sarah’s batch
when I took a course with her at West Dean.

The recipe has been modified over the years but here is the one I
got from Sarah:

-Boric acid powder 106.4 grams
-Sodium Acid Phosphate 70 grams (Di sodium hydrogen orthophosphate)
-Sodium Hydroxide 7 grams (Caustic Soda)
-Borax powder 70 grams
-Teepol 28.4ml (Dishwashing Liquid)
-Distilled water 1.5 litres

Method - weigh out the chemicals and dissolve slowly in lukewarm
water stirring constantly. The solution does not seem to deteriorate
with age, although it is less effective if it gets dirty. Originally
intended to be used as a flux/firestain inhibitor for silver it is
also effective for gold and base metals such as copper and brass. It
is not necessary to use any additional flux. The ideal way to use
the solution is to warm the metal first and then paint/or spray the
FM on so that it hisses and dries forming a protective layer. But
the glory of it was that it can be painted on cold and gently warmed
up, which was brilliant when you are still on your “L” plates at the
bench!!

I still consider myself to be very much a novice metalsmith, and
joined the Orchid community to learn as much as I could, so its nice
to give a little back so soon :o)

Regards
Emma


#12

Hi Emma,

Cooksons in the UK sell a product called Argotect, do you know if
this is the same mixture?

I keep giving it away, they sell it in a can big enough to last me a
couple of lifetimes!

Regards Tim Blades.


#13

Hi Tim,

Cooksons in the UK sell a product called Argotect, do you know if
this is the same mixture? 

I couldn’t say for sure… I’ve always avoided Argotect for the
simple reason it being a paste flux and all, I prefer the easy
application of a liquid I can spray on, guess I was spoilt with my
first bottle of FM Solution, its been hard to wean me off it ;o)

they sell it in a can big enough to last me a couple of lifetimes! 

I feel the same about the Vitex safety pickle that Cookson’s sell,
that tub just keeps going on and on!

Regards
Emma