Metropolitan's phosphoric flux to be available at Scaleforum

[Russ Elliott]

I'm pleased to report that pints of Metropolitan's patent phosphorix flux will be available at Scaleforum. He'll be behind the Bring 'n' Buy. I've bagged the first pint. Suggest PM John with your needs so that he can plan the quantity.

[Trevor Grout]

it should be noted that the pints are not for drinking unless your really hardcore......

[Paul Townsend]

Metropolitan's patent phosphorix flux will be available at Scaleforum.

How does this differ from the 12% I make up from P.Acid bought from Boots?
Does it have a magic ingredient? Are the pints neat or diluted? What price?

Googled the named material and got some fascinating but irrelevant hits!

[Jol Wilkinson]

Paul,

probably little different from your own brew or the products available from LRM, Eileens, etc.

Diluting phosphoric acid with distilled/purified/deionised water and adding a wetting agent isn't difficult. What Metropolitan John is doing is simply making it available to order in larger quantities, undercutting the usual suppliers and using S4um as a free platform from which to sell it .

Jol

[jim s-w]

Am i picking up a slightly negative trend to this topic? If you want some buy it, if you dont, dont.

How is a home brew mix of flux any different from a home built jinty?

Besides if its on the bring and buy its not a free platform is it as the society gets a cut.

Cheers

Jim

[Jol Wilkinson]

Besides if its on the bring and buy its not a free platform is it as the society gets a cut.

Cheers

Jim

Jim,

That's good, especially as I don't have anything for the B&B this year and so can't contribute.

And does the salutation "cheers" tell us that you are just putting your lips to a glass of it?

Jol

[jim s-w]

Lol

No, i wont be at scaleforum this year and besides as a none drinker i get enough of it through pepsi!

Cheers

Jim

[Paul Townsend]

Paul,

probably little different from your own brew or the products available from LRM, Eileens, etc.

Diluting phosphoric acid with distilled/purified/deionised water and adding a wetting agent isn't difficult. What Metropolitan John is doing is simply making it available to order in larger quantities, <snipped>

Jol

I haven't used a wetting agent or dil water. Results from decades of plain tap water seem OK. However I can see that using dil water might be better if your tap supply is very hard.

I can also see that adding a wetting agent would be helpful but only know of washing up liquid in that context so never used it for fear of contaminating the joints.

What is recommended wetting agent for phosphoric acid flux?

I am not at all negative about the stuff being sold on B&B...just like to explore all options and intrigued by magic ingredients! As I hope to be doing some etch soldering at Leatherhead in between selling BGS goodies I will road test a pint against my standard brew, visitors could enquire re results!

[Captain Kernow]

Good for John for making this available, although I'll save him the trouble of taking my pint to Leatherhead and ask him to bring it in to DRAG one night...

[Metropolitan]

I don't "sell" it. £3 a pint covers the cost and bottle and I am happy to let modellers have some should they so wish.

Anyway, I can't understand why any serious modeller would buy those silly little expensive pots of flux you see around when it is so easy and cheap to brew ones own.

TIP: To keep iron bits clean and healthy and maximise your soldering DISCARD dirty flux. Clean flux every session is a must IMHO.

Here's how to make your own:

Google phosphoric acid and select a retailer. I pay about £40 for 5 litres of 88% phosphoric acid delivered to my door. It comes in a huge glass bottle by courier.

Make up the quantity you desire by diluting as necessary with tap water (or distilled water in hard water areas). Add a nip of wetting agent. Bottle it up. You'll never pay or want for clean flux every again!!! It's so cheap you can splash it on with abandon without worry.

Also make a nice Christmas present for fellow modellers!!!

PS: 88% phosphoric acid is not toxic. (Coca Cola is about 3% phosphoric acid.) At 88% it can just about burn skin unless washed off and will sting like hell if it gets in a cut so wear plastic gloves and wash down the containers after decanting and bottling.

[grovenor-2685]

Make up the quantity you desire by diluting as necessary with tap water (or distilled water in hard water areas).

That's a bit vague for a recipe, What % acid do you use in the diluted result? And what do you use for a wetting agent?
Thanks
Keith

[Metropolitan]

Make up the quantity you desire by diluting as necessary with tap water (or distilled water in hard water areas).

That's a bit vague for a recipe, What % acid do you use in the diluted result? And what do you use for a wetting agent?
Thanks
Keith

No, It's not vague.

Decide what strength flux you want, I use 14% for brass and 12% for whitemetal but everyone has a different preference.

Then do the maths to dilute down from 88% (or whatever strength your PA is) to the desired figure. Easy. Use a calculator if its too difficult. If you cant work it out then dont bother.

A tiny drip of a very cheap unadulterated detergent is fine for a wetting agent. Don't use Fairy Liquid etc because it contains Lanolin. The wetting agent is however unnecessary because you can flood this stuff on to your hearts content!

[grovenor-2685]

Decide what strength flux you want, I use 14% for brass and 12% for whitemetal but everyone has a different preference.

Thanks, question answered, I would think a lot of purchasers of the small bottles would not have the first idea of the strength that they were using, and that includes me. Calculating is not the problem its knowing what value to aim for.

A tiny drip of a very cheap unadulterated detergent is fine for a wetting agent.

OK thanks.
Regards
Keith

[chrisf]

Memories of school chemistry lessons are evoked here. ISTR that one should add acid to water - AW - not water to acid - WA! Perhaps it depends on the acid being diluted.

Chris

[Paul Townsend]

Memories of school chemistry lessons are evoked here. ISTR that one should add acid to water - AW - not water to acid - WA! Perhaps it depends on the acid being diluted.

Chris

Doesn't matter for Phosphoric which is quite benign.

Matters hugely for some acids like Sulphuric, get it wrong and explosion results...mega nasty burns etc.

However even for phosphoric, wear old clothes and eye protection when diluting.

Most modellers will have Ian Rice's etch kit book(s) where he recommended 8% or 12% according to the job.
I use 12% for all with no trouble.

You can get 1/2 Litre or 1 litre bottles by ordering at Boots etc so no need to spash out on £40 unless you have a LOT of friends. Same for acetone etc for shifting Araldite.

PS
Because my late Mum was diabetic I inherited loads of small syringes and have used them for decades for my 12% brew. Please dont try mainlining it tho'

At S4um 2011 I bought a nice Japanese gadget "Flux pen". It combines a syringe and brush tip with safety cap etc. I have used this also for a year and highly recommend it.....not sure if it was from Eileens or Squires or someone else.