1. Welcome to Taxidermy.net, Guest!
    We have put together a brief tutorial to help you with the site, click here to access it.

Lutan-F tanning procedures

Discussion in 'Tanning' started by twinrivers, Oct 19, 2014.

  1. I am no expert on tanning but have followed the procedures of my instructor who has been doing this for 30 some years with great success. It interests me but I do not currently have the time to study the different processes and still maintain employment and a taxidermy business. She swears by Oxalic acid pickle and Lutan-F tan and for that reason I use it. So amongst all of the controversy that has been thrown on here about the Lutan directions being incorrect I decided to text her about this to get some clarification and I received an immediate phone call from her yesterday. She had attended several tanning seminars led by Bruce Rittel over the years and even notified the owner of Knoblochs about this topic for clarification. I know there will be some that disagree and have their own ideas and tanning preferences but through her research, training, and experience this is in a nutshell what I took away form our brief conversation: Raw/green hides must be salted prior to pickle, pickled hides must be neutralized prior to tanning, and you need to have a pH of 3.8 when tanning with Lutan-F.

    If hides are not properly salted the globular proteins/bacteria will not all be forced out of the hide. Salt for at least 24 hours (I dry salt). After salting you need to rehydrate the skin back to a raw state before entering the pickle. Using oxalic acid mix the pickle accordingly to a pH of about 1-1.5 prior to placing your hide in the pickle. Pickle and occassionally agitate for at least 24 hours before shaving, and after you shave return to the pickle for another 48 hours, agitating occassionally as well. At that time neutralize your hides with baking soda (sodium bicarbonate) to raise the pH and remove the acidity from the pickle. This is done by adding 1/2 ounce at a time and agitating the hide in the pickle for five minutes. Repeat this process untill you reach a pH of 4-4.5. By adding 1/2 ounce at a time you are slowly opening the skin pores and preparing the hide for tanning. If you apply too much baking soda too quickly you are risking slippage and twisting of the hair in the follicle (She had a name for it but I am at a loss right now). So now that your at a pH of 4-4.5 let your hide remain in this neutralized solution for 20 minutes agitating the hide to ensure all of the hide is being neutralized of the acid. At that time quick rinse your hide in water to remove the residual baking soda and damp dry your hide by spinning it or hang dry for about 30 minutes. After you have your hide drip dried, weigh it and mix your Lutan-F solution according to the weight of the damp dried hide. Once your tan is mixed is when you need to add oxalic acid back to the tanning solution to bring your pH back down to 3.8. She said it doesn't take much, maybe 1/4 to 1/2 ounce. Once your pH is at 3.8 add your hide to the solution for 18 hours (deer). Neutralize again following the previous procedures, and then remove and rinse the tan out of it and proceed to damp drying, oiling, and sweating. Sweat overnight in a refrigerator, and the next morning blot the water off of the skin, do final fleshing (skife) and either freeze or mount.
     
  2. Tanglewood Taxidermy

    Tanglewood Taxidermy Well-Known Member

    If you are OK giving pickled hides on forms to your customers instead of tanned hides, then keep doing it that way. If you want to give them tanned hides on their forms, neutralize after the tanning, not before.
     

  3. You are neutralizing after, but a pickled hide needs to be neutralized to a non acidic state before entering the tan in order to absorb the chemical. Then you bring the pH down slowly to 3.8 and soak for 18 hrs. Then neutralize back to 4.5. Where you at Mr. Rittel?
     
  4. And how would we be mounting pickled hides if they are neutralized, tanned at the pH of what lutan requires, and neutralized after tanning? They are tanned hides.
     
  5. Tanglewood Taxidermy

    Tanglewood Taxidermy Well-Known Member

    If you neutralize A pickled hide and mount it, then you have mounted a pickled hide. If the tanning doesn't take on a hide that has been pickled and neutralized then it is just a pickled and neutralized hide. The archives have this debate in there. If you haven't read it, it's a good read. What I took away from it is that you neutralized after tanning. Honestly, This subject is confusing because there are experienced tanners who say to neutralize after the tan, but go to the suppliers and read the instruction for the tan and they say to do it before. Who do you believe? I chose to believe the ones with experience as tanners because they had sound reasoning, but what do I know, so I just avoided using it any more after I read those threads. If those tanners are correct, then my reply was correct. If the taxidermists going by the directions from a supply company are correct, then my reply was wrong.
     
  6. Tanglewood Taxidermy

    Tanglewood Taxidermy Well-Known Member

    I some how missed the part where you bring the pH back down to 3.8 when I read your post. Sorry about that.
     
  7. Bruce Rittel's tanning method is shown in "The Complete Guide to Tanning" by Monte Burch and he says to salt, pickle, neutralize, and tan using Lutan-F. The only thing specific is to make sure when tanning with Lutan is to ensure the pH is in the 3.8-4.0 range by reducing the tanning pH to 3.8 with oxalic acid or equivalent. Over pH of 5 and some issues may arise I guess. Plus those instructions were written years ago by BASF in Germany and they had a disclaimer at the bottom of their article that they were unsure of their methods but it was how "they" did it there. I think maybe they have refined the tanning process throughout the years here in the US and found better results to neutralize before. Somethings gotta give here. Schools wouldn't be teaching a method of tanning if it was indeed improper. Not trying to start anything just waiting for Bruce to chime in and put an end to this madness! Just want beginners as well as all of us to be doing this properly is all. I love the results I get from Lutan, but if there is something we are doing improperly then we need to know. If Bruce does it this way I can hardly see why it would be the wrong way.
     
  8. cyclone

    cyclone Posts: 400001

    Before even getting into this deeper I will admit that I am not an expert on Lutan FN, haven't used it..
    I do understand some of the chemistry of tanning and understand that certain tans fixate to the collagen fibers at a particular pH range. Miss that range and all you have is a pickled hide. This issue definitely deserves further review.

    However, by your own admission you've had problems...
    Have you tried the process without the first neutralization step?
     
  9. cyclone

    cyclone Posts: 400001

    And by "neutralization step" I am referring to a pH adjustment from more acidic to less.
     
  10. I think we need Bruce Rittel to step in...
     
  11. cyclone

    cyclone Posts: 400001

    Simple question...
     
  12. Have not tried it without the first neutralization step, but then why would I? Doctrine says to neutralize after the pickle in every tanning process I have looked into. Why would I stray away from what is tried and true, and taught at probably every taxidermy school in the country that teaches tanning. The only problems I have ever had was trying to speed up the neutralization process by adding too much baking soda at one time. Doing that causes the skin pores to open too quickly and can cause the hair to twist or even slip. But if too acidic the hide will not be relaxed enough to accept a tan, which is why you have to neutralize. Actually if you DON'T neutralize a hide prior to tanning you are mounting a pickled hide, not a tanned hide. Pickling shrinks the pores and locks in the hair, that is why you can leave a hide in a pickle for long duration maintaining a pH of 1-2. When you neutralize you reopen and relax those pores and allow the tannins to chemically be absorbed into the skin fibers. Hence Kemal-4, it assists in the chemical reaction of relaxing a hide during the pickle and tanning stage... maybe by compensating for pH levels in the solutions. It isn't like your neutralizing it to a neutral pH of 7-8 like tap water anyway, it is 4-4.5, still acidic, but not too acidic too accept a tan. Your talking the difference in maybe an ounce at most of acid separating to two. A neutralized hide is partially still acidic, not raw hide. Neutralized enough to not be too acidic but enough to accept tan. It is like pouring water (lutan) into a sponge protected by a window screen (pickled) or pouring water through chicken wire (neutralized). Which would allow better penetration?
     
  13. Bruce_Rittel

    Bruce_Rittel Consultant Services

    Hi twinrivers!

    Oxalic Acid as a Pickle for Lutan FN or Syntans is only one choice for Pickling. However, we used it in AK for tanning because of the fly in Air weight considerations. But other Pickling Acids would also work in combination with Lutan FN or a Syntan. Whatever Acid you choose to use is purely a Tanner’s choice. I’ve used Formic Acid, Saftee Acid and Citric Acid successfully, as well as others that I have listed on my Pickling Formulations Hand-out sheet. White Vinegar is another Acid I’ve used successfully – so you’re not limited to only a Oxalic Acid Pickle in combination with using Lutan FN or a Syntan. Just make sure to monitor the Acid’s pickling pH and use the 1 Pound of Salt per Gallon with it. Always pickle at the recommended pH for the particular Acid you’ve chosen to use.

    For using Oxalic Acid to Pickle, it only requires 1 Ounce of Oxalic Acid, and 1 Pound of Salt, to each 1 Gallon of Water to maintain a 1.5 pH level. In AK this low usage, because we Air Lifted it in per 55 Pound Bag, saved us Postage.

    However, I do recommend starting out with a Salted Skin or cape. Why take a chance, if it’s an “iffy” skin or cape? Do what the Tanneries do, that Tan successfully 1000’s of skins and capes each year. Yes, it may be for storage purposes too, but their success with the skins and capes that have been salted and dried and then shipped to them, is admirable! Why process a skin or cape that has “loose” fur or hair? Or only “damp”, not dried? Salting and drying a skin or cape will usually save an otherwise questionable piece you may otherwise lose! The Salt will dehydrate the fur or hair follicles and “snug” up the epidermis around the follicle.

    I personally always desired to “Dry” the skin or cape after salting. Salt is relatively cheap, and I initially Salt it once, let it set overnight or at least 24 hours, drain, and then shake it out the next day. Then I’d reapply Salt to it, hang it over a Beam or Clothesline, then let the skin or cape dry out, drain, and store it until I had enough skins or capes to Tan them together. Then I Relax them all thoroughly before I Pickle them.

    Pickling is intended to “help” you prepare the skin or cape for Tanning. It isn’t a Tanner – I guess the best way to see it is to say it’s a Temporary Preservative solution that allows you to preserve the skin while you prepare it for the Tan. While it’s in the Pickle you can take it out, Shave it, Degrease it, and Wash it, if necessary! However, you should always let the cape or skin soak in the Pickle at least 3 days – or longer! Just remember to stir the Pickle every day – this will eliminate airborne mold growth! Although some Acids may Pickle faster then others, I like to use the “3 Day Rule” when it comes to Pickling. That way, no matter what I may use acidwise, or if I have a Shop worker do it – it’s always the same, and it generates no problems. After 3 Days you can safely Shave, Degrease or Wash a cape or skin!

    This allows it to fully absorb any Acid you may have chosen for your Pickling solution. It will also allow the skin to fully Pickle and swell it slightly so you can easily shave it thin. If you pull the skin or cape too early, like 24 hours after it was placed in the Pickle, it’s more than likely the skin or cape has not had a chance to fully expand, so you have easy shaving.

    You mentioned Neutralizing before the Tanning solution. In that respect, I would advise you that it isn’t intended if you do a good job shaving or thinning your capes and skins, or if you are dealing with thin skins like weasel, squirrel or skins that require no shaving. However, to accomplish a thorough Tan statically (Vat Tanning), it may be very helpful in accomplishing a complete Tan throughout the skin.

    However, personally I would prepare a separate Neutralizing solution. Do not use the Pickle to make a Neutralizer Bath. I would use 1 Ounce of Baking Soda (Sodium Bicarbonate) to each 1 Gallon of Water, and after I removed the skins or capes from the Pickle, drained them for 30 minutes to an hour, I’d place them in the Neutralizing Bath. But – only for 20 minutes.

    After this brief Neutralizing, always rinse the skin or cape and then allow it to drain for 30 minutes, so it wont influence your Tanning solution later.

    The intent of the Neutralizing Bath at this point is to create a skin or cape that has a more acidic center layer of skin then the outside of it. Tans are attracted to Acid. Usually they enter the skin or cape, ionized, seek out the more acidic part of it, and Tan the skin from the center, outwards. This ensures a complete Tan. In no way consider this a complete Neutralization of the skin or cape. It is only intended (20 minutes) to make the outside of the skin or cape a higher pH then the center of it, and attract the ionized Tan.

    Tanneries do not do this. They usually have competent Shavers and its likely all their work is shaved thinly. They also do their Tanning in a Wet Drum, which enhances the penetration of the Tan simply because of the mechanical action associated with Drumming.

    When you have your skins and capes ready to Tan, always mix the Tanning solution, and make it a 4.0 pH. This is before you place in the skins and capes. Make sure it’s correct. Now you can put in your skins and capes and after an hour in the Tan, again test the pH and make sure it’s still a 4.0 pH. If not, adjust it. Stir the solution, and if stabilized to a 4.0 pH, allow them all to Tan overnight (for 12-16 hours). Do not allow them to over tan! If you do, it will begin to cause a problem known as cross-linking. The Tan enters the fibers, but if they are in the Tan too long, they begin to also link to each other. The result is, you lose the stretch you need for Tanning a skin or cape to be mounted.

    Your Instructor mentioned a reference to “Cow-Licking”. It’s a condition I haven’t seen a good answer to solving it. Tanneries run into it when they Tan sometimes. The problem is, that in a load of 100-200 Capes or Skins, it will only happen to 1-5 Capes, and it’s difficult to point a finger considering the other Capes or Skins are normal. Yes, it is twisting of the hair follicle, causing unruly hair, that’s difficult to correct.

    Basifying is done to the skins and capes “after” they’ve been Tanned.It’s to neutralize the load, so if the customer soaks up the skins or capes, and doesn’t use a handful of Salt, added to it, per Gallon, it won’t Acid Swell. Usually the Load is neutralized and finished off at a 4.5-5.5 pH. That places them out of the Swelling range. Tanners refer to it as Basifying.

    After Tanning your Load for 12-16 hours, they usually dissolve some Sodium Bicarbonate first, then add it to the Tan and stir it. They let the Load soak in it for 30-45 minutes, then test it. If it isn’t in the 4.5-5.5 pH range, they add another 1 Ounce per Gallon of Tan of Sodium Bicarbonate and again, allow the Load to soak for 30-45 minutes, then test it. Usually it’s enough to bring it into range.

    The Load is now ready to rinse, drain and if thickly furred or haired, a quick Tumble or Centrifuge (Twice) is done – usually only 10 minutes, then blown out or Caged. The Load is now ready to Oil and finish.

    I hope this information is helpful to you. If you have any further questions, I would prefer you e-mail me at [email protected] (there is an _ between Bruce and Rittel).
     
  14. cyclone

    cyclone Posts: 400001

    http://www.prismadye.com/Files/TDS/EN/LUTAN%20FN.pdf
     
  15. Bruce thank you for clarifying the process. As someone beginning to tan your step by step answer is very helpful, and clears up my confusion concerning a 20 minute neutralizing step and basifying. Knowing the reasons sure aids understanding. I'll mark this thread for future reference.
     
  16. Thank you Bruce for the clarification and ending this madness. Very much appreciated!
     
  17. Evicene

    Evicene New Member

    10
    0
    Amazing write up, thank you Bruce!
     
  18. Mr.T

    Mr.T Active Member

    Not so fast twinrivers.

    Old Shaver, who has worked at several tanneries, and the inventor of the Tru-Bond tan method, has already cleared this up on a previous thread. Stating that the Lutan, being a mineral tan, unlike syn tans like Bruces EZ100 , or other tanning agents, works better at full acid. He explained it, as I was of the "must neutralize first" crowd.

    http://www.taxidermy.net/forum/index.php/topic,332510.msg2262647.html#msg2262647
     
  19. Mr.T

    Mr.T Active Member

    Thank you Cyclone for finding the "from the horse's mouth" spec sheet on the Lutan process, of neutralizing after the tan.
     
  20. I will try it full acid on a spare cape just to see how it turns out. I am Lutanned out for the week. Still need to sell me on the Tru. Bond though...lol. if tru bond is as good with less headaches then I may try it out as well. Take care Haas.