Soaps/Acetone

[photoman290]

what would you say a clear 50/50 test indicates as far as ppm levels.
I know I have tested one of mine at 76ppm.

I still do 50/50 tests as it's quicker and easier than Nige's soap test (though the buck stops at the titrated test for accuracy).

The trouble is that "clear" water covers a range of ppms soap, probably up to 100ppm even before it begins to look less sparkly.  This is where lasers come in, in a dark room a laser through the water layer will show a beam right down to the lower ppms.  If I can't make out the beam in a dark room I reckon it's down at <25ppm (though I've not done any formal testing on this - might be worth experimenting!).  I always use near boiling water to get quick and clean separation.  I feel that the 50/50 still has a place in testing but it's very much one of those things that takes a while to get a feel for, rather than the titrated test which is consistent every time.

 in the days when you could still get scientific instruments for next to nothing i had a thing called a specker. very simple device.
 it had 2 photcells back to back in the middle and 2 lights at the ends of a tube. there are 2 holes in the tube equal distances apart from the centre.  you put a test tube with a standard solution, in our case clean water. in one hole and the solution under test in the other. soapy water in this case.  turn on the lights and read the difference in voltage on the photocells. quick and easy to do with 2 cheap multimeters. or you could make it as complex as you wanted to with go no go leds or something. you would need to balance it first with 2 test tubes of  the standard solution to compensate for any differences in the  photocells.
the key thing is the principle. its straight out of john strong if anyone remembers his  column in scientific american. it can be used for much more complex than  just soap detection by using different refractive index solutions  and different types of glass but should work fine for a simple soap test. if you where very clever you could make up a soap test kit with the correct colour index and use that as a standard.  would need to establish the standard first of course. nigel could do that has he has most experience of the test he could then send out test tubes with a standard colour. not sure how long it would stay the same colour though. maybe some permanent dye the right colour would be better.

[Tony]

I used to work for a company that designed Diesel smoke testers for MOT.  Light at one end of tube, photocell at other end, you had some "calibration smoke" (actually a special darkened glass to insert into the tube) then you could go ahead and test using exhaust smoke.  The hard bit was stability of the optics over time and keeping them clean.  Very similar principles.

Particle counters use laser backscatter, no reason why we can't do the same with a laser pen and judge by eye

[photoman290]

ah but has steve has pointed out eyes vary.

[K.H]

So we are saying that a 50/50 can give a positive (clear) result at over double the ASTM?

[K.H]

As an aside does anybody object if I change "the three" to four on the soap page? As I feel water can do as much if not more damage

[Tony]

Which page is that Keith?

[Julian]

I think he means the top of the soap test page.

I'd say yes, go ahead and perhaps qualify it further by saying ..."one of the four main" ...

[1958steveflying]

Results are in:

- two 500ml samples from a batch that has had the Methanol bubbled off
- 0.1ml Acetone put in one sample
- settled for 9 days

Both have a similar layer of light soap at the bottom, and a soap test indicates very similar soap content, so Acetone for settling alone does not appear to help at this concentration.

Just a thought Tony, if you still have them would you try adding say, 200ml water to each as they are, shake the hell out of them to get the soap back in and settle to see what happens, then if the water is a different colour soap test the Bio again.

[nigelb]

The future is sometimes to be found in the past. I think I'll put that in my sig

Totally agree, WBD and settle all the way!  No water in my process thankyou very much

.......just HMPE's and days upon days of waiting 

[Head Womble]

I've made a start on an acetone wash page,
it's by no means compleat as yet, or in the right format (I've tried but got confused).

Please take a look and feel free to edit so it's in the right format.

http://www.biopowered.co.uk/wiki/Using_acetone_to_aid_soap_removal

[Julian]

Good start, but I can see you're thinking forum code ... you need to think wiki code!  Just a few simple bits of markup which can be copied from any wiki page or from one of the stickies on the forum.

If it's OK with you I'll start another thread to guide you through the page, in the hope that it will be useful to others too.

Did you start by copying and pasting from the "New Page", page?

[Head Womble]

Yes I started by copy/past the "new page", but got lost soon after.

Please do start a new thread to guide me through, I need help.

I'm fine with spanners, electrics, pipework, anything with my hands really, but this is using my head, and that's allways been the weak point.

Edit to say my spelling is also a weak point (before anyone else said it).

[Carrington]

Just had a look at the page and it reads well.
Good work mark I know who to send my findings to on new test for  the write ups

[Tony]

The future is sometimes to be found in the past. I think I'll put that in my sig

Totally agree, WBD and settle all the way!  No water in my process thankyou very much

.......just HMPE's and days upon days of waiting 

I'll see your multiple water washes and raise you playing with the kids in the warm while it gets on with it on it's own while the recovered Methanol sits there waiting for the next batch

[Tony]

I've made a start on an acetone wash page,
it's by no means compleat as yet, or in the right format (I've tried but got confused).

Please take a look and feel free to edit so it's in the right format.

http://www.biopowered.co.uk/wiki/Using_acetone_to_aid_soap_removal

Easily understood (the most important bit about portraying information), the rest is just prettying up which it sounds like Julian would like to encourage you to learn - but failing that just a bit of formatting from a few wiki old hands* and that's perfect

*personally I can never remember wiki formatting and have to crib from existing pages every time!