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Thread: Sofa cracking, unknown leather type

  1. #1
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    Default Sofa cracking, unknown leather type

    I'm attempting to repair as best we can, an older leather couch we inherited. The arm rests look like they weren't ever cleaned & its begun to crack on the cushions as well. I'd like to see an end to further degradation & bring back whatever I can. We did attempt to condition & it did make the leather darker, I'm fine with color alterations, I'm just trying to salvage what we can & try to bring some health back.
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    Last edited by babelsgp; 04-28-2017 at 08:29 PM.

  2. #2
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    >>> We did attempt to condition & it did make the leather darker,

    “Conditioners” are not used originally in any modern tannery where this leather comes from - most conditioners also cautious on the use on suede, (since the finishes have worn away, it makes the appearance darkening effect more obvious). To rejuvenate the leather back to its original suppleness using Hydrator-3.3 > Fatliquor-5.0 > Hydrator-3.3 is comparable and will not produce such blotchy darkening effect.


    >>> The arm rests look like they weren't ever cleaned & its begun to crack on the cushions as well. I'd like to see an end to further degradation & bring back whatever I can.


    It is very important to note that the leather should not be allow to dry without sufficient Fatliquor-5.0 (15% of fat and oil) otherwise the crack may accelerate. This is known as the “wet process”, the same principle practice in modern tannery. Only safe to let the leather dry only after the fatliquoring process.


    >>> I'm fine with color alterations

    There are two options to color refinishing. One (1) is to retain the original “Aniline” characteristic and two (1) is to alter with camouflaging the damaged areas to even out its appearance, prior to top-up with “Aniline” finish.

    Here is the pros and cons:

    Option (1).
    Just a topcoat refinishing with AnilineTop-76G.
    And here are the sequence of process based on Kit-A6.tc
    Name:  Kit-A6.tc.JPG
Views: 57
Size:  1.47 MB
    http://www.leatherdoctor.com/kit-a6-...finishing-kit/
    The sequence of process is as follows:
    1) Degreasing - Degreaser-2.2 > Acidifier-2.0/Rinse-3.0 > Hydrator-3.3
    2) All other stains removal follows as the next continuous step while keeping the leather wet or at least 25% moisture content from preventing cracking due to insufficient percentage of fatliquor (fat and oil) content of average 15%.
    3) Hydrator-3-3 use to reactivate the dormant dyestuff within the leather structure to resurface (may used part of the trim for a test - soak up until a little moisture ooze out of the leather structure and leave it on a zip lock back for 72hours - with interval topping up to that level of moisture fullness). Remove the sample from the zip lock bag and wipe the wet suede surface until the towel shows dry (check for dye transfer if any which is a good sign and continue Fatliquor-5.0, with each absorption cycle more is applied until the last application show surface saturation then leave to slow complete dry. When dry compare it with the other half to inspect increase in color saturation. Note that in the actual application, AnilineTop-76G will amplify the color saturation further.
    4) This is a simpler approach, may not get the rich new color but will retain the originality. A 100% is necessary
    other any un-removed stains may show through. Using a satin AnilineTop-76S will make the stain less clear is another option without the need to alter its original aniline characteristic (maintain its original value).

    Option (2).
    A complete refinishing with Aniline-76 system based on Kit-A7.cl
    Name:  Kit-A7.cl.JPG
Views: 57
Size:  1.42 MB
    http://www.leatherdoctor.com/kit-a7-...finishing-kit/
    The color choice would be dark enough to camouflage those dark natural scar marks we see on picture #4. Note that it takes more skill to apply a ”transparent” dyestuff then an “opaque” pigment. That is also why transparent varnishing furnishing and musical instruments cost very much more then flat painted. Bare in mind, this is not a cheap leather to have to keep up with the original standard. That is why matching Aniline-76 system is recommended then the easier application of Micro-54 system. Micro-54 system will devalue this leather if we take that route.
    The sequence of process is as follows:
    1) Degreasing - Degreaser-2.2 > Acidifier-2.0/Rinse-3.0 > Hydrator-3.3
    2) All other stains removal follows as the next continuous step while keeping the leather wet or at least 25% moisture content from preventing cracking due to insufficient percentage of fatliquor (fat and oil) content of average 15%.
    3) Hydrator-3-3 use to reactivate the dormant dyestuff . . . (same as above option (1)).
    4) Without letting the Hydrator-3.3 from complete dry or about 25% moisture level or wiping it from damp until towel shows dry, Fatliquor-5.0 continues described as above.
    5) Any fatliquor residue remaining on its surface has to be removed with Hydrator-3.3 again.
    6) Dry preparation and is ready for any repairs.
    7) Aniline-76 system comprises of Adhesor-73 > Aniline-76G/S > AnilineTop-76G > Protector-B/B+

    See this guide for other known stain
    Name:  aniline-a.fs-full-sauvage.jpg
Views: 55
Size:  310.4 KB

    Let me know your option and we can go into further details.

    Roger Koh
    Leather Care System Formulator
    Consultant / Practitioner / Instructor
    web: www.leatherdoctor.com
    forum: www.leathercleaningrestorationforum.com
    email: roger@leatherdoctor.com
    Last edited by Roger Koh; 05-02-2017 at 12:22 AM.

  3. #3
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    I want to begin with option 1 and see how the leather responds to the degreasing, returning to proper pH & improved fatliquor. Would impregnator help with the leather fibers? How do you measure the humidity?

  4. #4
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    >>> I want to begin with option 1 and see how the leather responds to the degreasing, returning to proper pH & improved fatliquor.

    Besides degreasing unwanted aftermarket products will also need to remove other stain (see above matrix row #1 to #22) - otherwise the new topcoat will make all these ugliness show through - the topcoat cannot differentiate between the beautiful grains and the contamination and both will show through - and to remove the topcoat will be a tougher job to perform so make sure they are inspected to a very high level of cleanliness. Also remember that all these contamination has penetrated and is now below surface and ‘reverse-transfer’ technique with Hydrator-3.3 plays an important role. As well as using the leather Eraser-4.

    For your reading about the usage o Hydrator-3.3 and more to read here:
    http://www.leatherdoctor.com/hydrator-3-3/

    F - Reverse-Transfer Suspended Soiling:

    Capillary action or wicking process is deployed to move penetrated and suspended soiling to resurface by reverse-transfer technique with Towel-T5. First the leather structure needs to be hydrated to facilitate colloidal water movement within the structural inter-fibrillary spaces, it will also require saturating Hydrator-3.3 to move the suspended soiling upwards. As it wicks through the Towel-T5, soilings are trapped instead of still remaining on the leather surface to be easily peeled off. In practice the following steps are adopted - Instruction . . . F1- The thickness of the leather is hydrated to an optimum level with moistures oozing out when gently pressed between thumb and fingers. F2- It is then cover up with plastic wrapping to control evaporation and let it dwell up to 72 hours to loosen and suspend foreign soiling particulates. F3- The plastic wrapping is removed and replace with Towel-T5 without airspace to trap soiling as it dries instead of remaining on the surface. For it to stick onto the leather surface, the Towel-5 is spray wet with Hydrator-3.3 and brush out the air space with horsehair Brush-1 at a 45 degrees angle without tearing the towel tight. As it dries it will shrink back and tighten further sticking tight onto the leather surface. Recommend that Fatliquor-5.0 is replenished in combination at this stage especially if the leather has already show signs of cracking. Note that dried leathers with insufficient fatliquor (less then 15% fat and oil) content, when dry again will likely accelerate any existing cracking. F4- Towel-T5 is peel off when crispy dry and surface residue erase with Eraser-4 or Eraser-5 for suede accordingly prior to fatliquoring. F5- Fatliquoring continues and is repeated with each almost drying cycle until saturation and is leave to slow natural drying. F6- Fatliquored dried surface residue is driven into the leather structure by brushing in conjunction with Hydrator-3.3 until milky residue if any turns crystal clear. F7- Surface clear moisture is extract with a cotton towel until towel shows dry. F8- Staking, stretching, massaging or cross flexing one more time before the leather is completely dried for the desired suppleness.


    >>> Would impregnator help with the leather fibers?

    Impregnator-26 is formulated for internal leather structure weakness to level up with the rest of the leather.
    Need to test for any color saturation effect for satisfaction before actual application. Anyway it is not meant to remain on the leather surface or grain - strictly below surface - easier to work from the suede side, which, is more open, or directly into cracks and let dry before further repairs with Bond-3D.


    >>> How do you measure the humidity?

    Not humidity, it is to measure the leather structure of its fatliquor (fat and oil) content with a leather moisture meter or an equivalent like moisture meter or skin moisture analyzer at least to tell the before, during and after reading. Essentially it is to measure the fat and oil when the leather is dry. And 15% average is the optimum level.
    Any crack will accelerate if the fat and oil content falls below 10%, so be careful only to let the leather dry after rounds of Fatliquor-5.0 application.

    Readings:

    Leather Approximate Quantity or Percentage of Fatliquor:

    The quantities of fatliquor (fat and oil) contents retained in the leather after an universal tannery fatliquoring process may varies up from 14% to 16% depending on the leather types and it usage. This percentage drops as the fat and oil content diminishes or leaches through ageing, water, heat or chemical overexposure. Leather rejuvenating or fatliquor replenishing is base on weight of the leather in relation to the percentage of remaining fatliquor. A simple calculation of percentage of fatliquor topping up requirement would be as follows: If the weight of the leather in question is 100gm and fatliquor (fat and oil) content meter reading is less than 1%. By applying 80gm of Fatliquor-5.0 to it will deliver an end result incremental of 13.3% fatliquor when dry as the 66.6% water contents evaporates. In the leather rejuvenating Hydrator-3.3 > Fatliquor-5.0 > Hydrator-3.3 system, Hydrator-3.3 plays an important role by relaxing, opening up the inter-fibrillary spaces, facilitating and redistributing colloidal water movement, protonating and doing all the pre-conditioning work prior to fatliquoring including cleaning up any excess surface remnants to have a sticky-free surface. In practice with severe dryness the ratio for Hydrator-3.3 is 2 to 1 of Fatliquor-5.0. It works out to be approximately 160gm of Hydrator-3.3 plus 80gm of Fatliquor-5.0 to replenish a 100gm dry leather from less than 1% back to the original tannery up from 14% to 16% fatliquor content. In every bottle of Fatliquor-5.0 by weight content is comprises of 16.66% ionic negative (-ve) charged fat and oil, and 83.33% of water, the water content that encased the fat and oil molecule in an emulsion suspension when hydrogen bond with the ionic positive (+ve) leather protein fiber will break free and discharged clear from the leather structure to the surface.

    Roger Koh
    Leather Care System Formulator
    Consultant / Practitioner / Instructor
    web: www.leatherdoctor.com
    forum: www.leathercleaningrestorationforum.com
    email: roger@leatherdoctor.com
    Last edited by Roger Koh; 05-03-2017 at 11:02 AM.

  5. #5
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    After the unwanted products have been purged, will the damaged leather begin to "heal" during the hydrator 3.3>fatliquor 5.0>hydrator3.3 process? How could I damage the leather further, like once I remove the unwanted products and I've cleaned various stains and I'm fattening & hydrating the leather, are there any movements or actions I should avoid when wet, or can I gently begin to manipulate the fibers when wet to help the cracking areas. I feel it's like rawhide in several places, it doesn't feel thin, but definitely splitting and clumping fibers. I don't want to damage the remaining intact fibers next to the splitting areas or cause ripping. I won't be able to access the suede side on the arms. The suede side on the seats seems to be in good shape.
    Last edited by babelsgp; 05-03-2017 at 08:09 PM.

  6. #6
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    Also another point to note about the arms is that the first time I attempted to clean with saddle soap (probably not good in hindsight) the leather on the arms was indeed slimy & tacky as it dried. I'm aware that this indicates an alkaline environment & will need the acidifier application and direction you have under the hydrate 3.3 directions D & G, do I degrease first and then proceed with G?
    Last edited by babelsgp; 05-03-2017 at 08:12 PM.

  7. #7
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    >>> After the unwanted products have been purged, will the damaged leather begin to "heal" during the hydrator 3.3 > fatliquor 5.0 > hydrator3.3 process?

    Picture #1 shows the lighter almost mud cracking appearance, is horizontal shrinkage due to diminishing fatliquor (fat and oil) content. At a 15% fat and oil moisture, it will become less apparent. However, it will need Hydrator-3.3 to act as a relaxer to lessen up the shrinkage appearance and dwelling up to 72 hrs with evaporation control to undo the shrinkage appearance. When it reaches the desired appearance, 75% of the water content has to be evaporated to make room for the Fatliquor-5.0. The water content of each Fatliquor-5.0 application need to be evaporated as well and that comprises of about 83.33%, thus a lot of water goes into the leather that also purges out any foreign contamination. This surface water content will then be wiped with a clean white terry towel until the towel shows dry before any more Fatliquor-5.0 can be replenished. Ultimately, what the leather need is just the “Fat and Oil” and all the water contents of both the Hydrator-3.3 and Fatliquor-5.0 dries up. Thus without sufficient fat and oil, the leather may still be back to its original appearance. And all the Hydrator-3.3 has gone to waste and you may have to start all over again. The leather may not “heal” at all and make worst by the empty drying process.


    >>> How could I damage the leather further, like once I remove the unwanted products and I've cleaned various stains and I'm fattening & hydrating the leather, are there any movements or actions I should avoid when wet, or can I gently begin to manipulate the fibers when wet to help the cracking areas.

    This process in the modern tannery is known as the “wet operation” and it moves through the steps of cleaning the raw skin keeping the skin wet all the times, until all the foreign contaminations are removed, pH balanced, tanned and the final stage of fatliquoring up to a 15% fat and oil content before allowing it to slow dry. We are following the same tannery principle in this very safe approach.


    >>> I feel it's like rawhide in several places, it doesn't feel thin, but definitely splitting and clumping fibers. I don't want to damage the remaining intact fibers next to the splitting areas or cause ripping.

    The rawhide feeling is a sign of leather denaturing or reverting to rawhide due to unstable leather pH chemistry, The denaturing leather has a different feel when wet as compare to the non-alkaline overexposure areas, they feel tacky and in worst cases slimming, similar tactile feel as a meat or fish squeaky-feel when fresh and slimy-feel when stale. These denatured areas need to be treated with Acidifier-2.0, wipe and soak to dwell until it return to a healthy squeaky feel. This is done over the entire panel, hoping to attract some of the fugitive tanning-agents back to the denatured areas. This is a salvage attempt to save your leather, so understand the science and logic behind your action, otherwise you will innocently accelerate with undesired result.


    >>> Also another point to note about the arms is that the first time I attempted to clean with saddle soap (probably not good in hindsight) the leather on the arms was indeed slimy & tacky as it dried. I'm aware that this indicates an alkaline environment & will need the acidifier application and direction you have under the hydrate 3.3 directions D & G, do I degrease first and then proceed with G?

    Yes as a “wet operation system” Degreaser-2.2 > Acidifier-2.0 > Hydrator-3.3 > Fatliquor-5.0 before allowing a slow drying.


    Roger Koh
    Leather Care System Formulator
    Consultant / Practitioner / Instructor
    web: www.leatherdoctor.com
    forum: www.leathercleaningrestorationforum.com
    email: roger@leatherdoctor.com

  8. #8
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    I received the initial products. I've begun the degreasing>rinse>acidifying. I am not drying after the acid step, only letting the water to evaporate some prior to the hydrating process so the hydrator 3.3 will become absorbed. I am doing the hydrator 72hrs next. Then reverse extraction. I need to buy cleaner 3.8 & some concentrated products for more sections. As I understand I don't want my leather to completely dry out until fatliquoring, as it will further the dry problems. During the reverse extraction I'm wanting the paper to become bone dry, does this imply the leather will also become dry? Am I missing a fatliquor step in there? (Found the answer in the directions for extraction to use the fatliquor during the extraction process) Also when I wait for more products or if at any point I need to stop and take a break between corrective steps, should I do the hydrator3.3>fatliquor>hydrator process to dry?
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    Last edited by babelsgp; 05-12-2017 at 06:32 PM.

  9. #9
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    >>> During the reverse extraction I'm wanting the paper to become bone dry, does this imply the leather will also become dry? Am I missing a fatliquor step in there?

    In a specially dry and surface damage condition, Fatliquor-5.0 the lifeblood of leather becomes very important factor and the leather has to be fatliquored a few rounds so that it will not further crack when dry. The sequence recommended should be Hydrator-3.3 > Fatliquor-5.0 (till fully saturated) then ‘reverse-transfer’ using the Towel-5.
    That way the leather only dries once after Fatliquor-5.0 to an average of 15% to prevent accelerated cracking from insufficient fatliquor (fat and oil content).

    >>> Also when I wait for more products or if at any point I need to stop and take a break between corrective steps, should I do the hydrator3.3>fatliquor>hydrator process to dry?

    Any in between dry should always ends with Fatliquor-5.0 averaging 15% of fat and oil when dry.

    Roger Koh
    Leather Care System Formulator
    Consultant / Practitioner / Instructor
    web: www.leatherdoctor.com
    forum: www.leathercleaningrestorationforum.com
    email: roger@leatherdoctor.com
    Last edited by Roger Koh; 05-15-2017 at 08:02 PM.

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