Posted: 30 June 2007 at 11:16pm | IP Logged

Dear Zercas:  I, perhaps cannot teach you anything new, but perhaps I can teach you something very old!

From volume one of O'Flaherty, etc. that I have thanks to Waldo, I quote Wendell Morris in Chapter 7, pg. 236 the following sentence:

Posted: 30 June 2007 at 11:49pm | IP Logged

The concept of reducing alkalinity in the beamhouse to avoid basic case hardenning has lead to decrease of sulphide and inrease of hydrosulphide in many hardwater based tanneries.  I personally favor the decrease of sulphide and the addition of sulfite as a solution to the same problem!  I am sure these concepts are applicable in León that has very simmilar water properties as Chennai! I both cases I did not do too much work in the beamhouse as my bosses did not get involved in those chemicals and hence I signed off as retanner!  Ramachandran has a lot of cumulative experience coupled with technological folklore that is very prelevant in tanners in many places, and is a source of information that must be processed scientifically to understand what happened to give rise to the many rules-of-thumb that become dogma and are so common to our field!  Surface grain swelling can be detected easily with an indicator and in lime-splitting with a little experience , as well a by the survival of hair roots (called cañon in your neck of the woods!) past the beamhouse.  Most likely sealed in  hair-roots dissappear in the bating and pickle operations.  I did some brief work at CONCURMEX, and lead to some excellent coach type leather with my AAA retannage.

Posted: 01 July 2007 at 1:29am | IP Logged

Dear Mr.David

On behalf of the tanners in Pallavaram Area May I invite you to do a trial for Full chrome glaze kid with pallavaram water.

The process is from US or Europe.

We will supply the wet blue and the chemicals.

Hope you accept this invitation

Posted: 01 July 2007 at 7:09am | IP Logged

Just because a wive's tale or superstition has survived many generations, ie published 50 years ago, does not make it any more accurate or true!  Bullsh*t is still bullsh*t.  Note that the author offered no evidence or even logic, just a blind "observation."  Note also that generations have been making leather in this hard water the "wrong" way for centuries with very fine results. 

You go much too far when you state that sulfhydrate is being used to quell the effects of hard water on beamhouse alkalinity.  Sulfhydrate is being used almost universally in advanced tanning systems, hard water, soft water and otherwise.  The reason is to reduce the pH and consequent swelling risk from sodium sulfide, not hard water. 

Granted there are a few select and delicate conditions in which hard water may have trivial effects, ie stability of badly prepared emulsions, color of cheap dye or dye and syntan preparations, etc.  None so tough that a little minor adjustment can not compensate, just as tanners have been doing for centuries, some even taking advantage of the of minor differences.  But the rest is huey.  Take into consideration the huge salt loads added in every step, carried from one step to the next and where are those ppm hardness factors.  No, I don't care if those ppm calcium hardness numbers are thousands!  It is still spit in the wind compared to the tons of calcium (not to mention dirt and metals and more) in the lime, even the curing salt, tanning chemicals, etc.  These are not pure laborabory chemicals, these are mined soil and rock with mountains of attendant contaminants.  Where is this drop of hardness when the whole ground up truck load of rock is dumped into that water, and it is there from the cure, the lime, the delime, the tan, even the tan. 

You are swatting at knats when the place is full of hornets!  You are inventing practices to make you look busy and smart to look good in the face of ignorance and make a big enterance.  It sounds good, it looks good, so what that it is a delay tactic to get to the real issues and get time to get a little sense of the place and conditions.  Great if that is what you want or need, but don't turn it into more than it is even in your own mind to justify it. 

Sergio has the right point, show me the real evidence, not more whimsical quotes of other fools.  Add huge hardness to a load and show the difference.  Put some real metal in the fire!  Document how a tiny speck in the water affects a mountain of salt, lime or other really overloaded bath!!!

Posted: 01 July 2007 at 10:26am | IP Logged

Waldo: I have seen the problem several times in my tanning experience as previously described by me, and corrected it by controlling alkalinity-swelling in the soak and beamhouse.  Let's see if Aneel Tariq betters his beamhouse process concerning enhanced growth wrikles in the winter time by applying my suggestons.  Any source of many, that  I quote to you, including respected authors in our field,  you have called  fools.  Have Zercas translate my saying in Spanish.  At the end of my career, I need not to make any great damatic appearance entrances!  Beamhouse research is generaly minimal by the chemical firms since the generic nature of most of the products used does not justify it.  Never-the-less leather is still made in the beamhouse!

RRamachandran: ask ARK or even TATA about my glazed goat formulation done in India!

Posted: 01 July 2007 at 11:04am | IP Logged

I am not talking abt tata or ARK.

I want you to give a good result using pallavaram water.

You can make good dyeing with pallavaram water thats what you said. for the last 35 years we are buying water from other sources and  dyeing suedes and uppers. If you prove that you can make leather with fastness with pallavaram water you will be great! and remembered in Chennai!

When you visit chennai, please let me know and I will take you to a Tannery in Pallavaram  where we can conduct trails.

Please note we will not buy soft water but use Ground water available in pallavaram.

Let us take few Scientists also from CLRI.

Hope you will accept my invitation.

Please note I am not challanging You.

I need your help. So that the tanners in pallavaram area can save some money and cut cost of production.

Will you Help us?

Posted: 01 July 2007 at 1:22pm | IP Logged

Sir David is indeed a fine, wise, experienced and wonderful chemist, physist, tanner and gentleman, but when he is wrong, he is just wrong.  His past achievements are many and great.  His future ones will be remarkable and better.  He has my great admiration and respect.  But he is still wrong on this one.  We are resorting to quotes, stabs and jabs, when we should be simply looking at the evidence (which does not include I say so or he said so or everyone says so). 

What is the hardest water?  600 ppm?  1500 ppm?  Clearly those are insane numbers, but what is that to 10% filthy salt, 5% technical lime, even reagent grade materials in high percentages?  Absolutely nothing!  Remember 1000 ppm is only 0.1%!

Posted: 01 July 2007 at 4:33pm | IP Logged

Waldo: You can follow selective grain swelling in the beamhouse just by using phenolphtalein, if you are willing to cut!  If you believe that it is an imaginary effect in spite of of my references to Thorstensen, Heidemann, Bienkiewicz, Morrison, others, and my own experience as well, I am sorry.  "Rollers" are an extreme case of differential grain swelling! They are certainly real! OK, if you want to use distilled water and add, let's say 3-4% soda ash in the soaking to make sure and then check for differential surface swelling--go ahead, I am sure you will find it.  I know that adding 0.5% soda ash in rain water is usually OK, but I have seen bad effects when you use 1.5% soda ash in two additions done in 600ppm, pH 8 water!  These bad effects such as enhanced growth wrinkles, sealed hair-roots surviving into the bating-pickle, convex bending into the flesh, and exessively turgid limmed white hides, very good shrunken grain effects at the end, all dissappeared after eliminating the soda ash competely and using bisulfite/sulfite and less sulphide and adding the lime more carefully using the same source water!  All of this achievable without asking for a water treatment plant for the beamhouse!

Ramachandran:  After fixing usualy with too much acid anyway, many tanners in India will proceed to extensively wash in water at pH 8 with many anions that compete with the dye for cationic sites, and then wonder why the dye is removed by such treatment!  Then they rightfully blame the water instead of themselves for not understanding what is hapening !  The real solution is to slighty acidify the wash-water with 0.4-0.6% of formic acid before adding to te dyed leather such as the pH is about 4 or a little less, and I will even add a small amount of aluminum sulfate, although you could use an expensive quaternary amonium compounds as well to get good fastnes properties! Hard and slightly alkaline water can be used in dyeing under low, cool, float conditions for excellent penetration, but then needs massive hot and acid water with a cationic dye fixer, before subjecting to my previously described washing bath.  Do not just blame the water--do something to correct the problem!  When I sugested to a technician in León to wash the dyed leaher in slightly acid water, he said: "Here in Mexico we do not wash blacks!"  He was also not aware of how to use his water properly, but knew he would extract the dye if he did.  These errors are due to deficient chemical education of the tanners.  The CLRI, CIATEC and such do not waste their time i such endevours!

 Neutral salts are generally dye penetration auxiliaries, and please remember what goes in easily,comes out easily!  Thus salts generally present in Chennai water will inhibit dye (and fatliquor) fixation.