issinglass amount?

Hi Andrew,

I am not a very experienced bowmaker and cannot tell you in gramms how much glue you need for a bow, but I myself bought 250gr "Hausenblase" (bladder from sturgeon) and think its enough for at least 4 - 5 bows and its the strongest natural glue.

But, I read an article about Lukas Novotny, that his first bows break between core and horn using only(!) fishbladder-glue. A friend of him, who is a chemist, told him, that fishbladder-glue has a too big molecular-structure to get a solid binding with horn, which does not suck like wood or sinew.

Too a friend of mine, who build a korean bow, learned that hard way. The horn went off.

My advice: ask Adam Karpowicz, he sure can help you.

Peter

To all: please correct me if you did another experience.

Maybe horns tendency not to bond well with the glue is why according to this History channel show, the Mongols didn't boil their ibex horns ,they soaked them in fermented milk till they became flexible.

http://www.history.com/media.do?action= ... _broadband

I just got one these ibex bows for my brother for christmas , we both like it a lot. Have not shot it yet ,letting it acclimate .

Ralph; I think that that was a joke. It is the bowmaker that you must soak in fermented mare's milk, or vodka; not the horn. -j-

Maybe ,it sure helps me. :D

But I do similar things with my horns ,and I know a few others who age or soak their horns in something other than water. Most of these guys consider their processes trade or family secrets so..........

Hi guys, cool!

Waterbuffalohorn, which is mainly used for turkish bows, is only flatened with boiling water. As I know, the hornstrips where layed, sorry don?t know the correct writing, in "Nafta", its a kind of benzine, like you use it to clean wounds. But it is only to dissolve any grease, that could be in the horn, especially "green" horn.

Another opportunity for the bowmaker, Jack? :lol:

Peter

Nafta is diesel.

Rapsod,

The correct writing is Naphta or Naphtha (from Persia nafata which means outsweat). This were light flameable liquids from oil. As we know, diesel does not burn when its liquid.

Peter

I am not sure if this would be any use, but Klopsteg advised boiling the horn in Glycerin, which has a higher boiling point than water. The Turks and others appear to have boiled the horn in water and then further heated it over a charcoal brazier to reach the required temperature. Klopsteg's suggestion was made in order to speed up and simplify the process and not because the old way did not work.

I would stay away from any benzine based product for health reasons. Hot glycerin in dangerous in purely physical terms.

The late 13th C Italian crossbow makers used a thick solution of soap to boil their Ibex horns in.
This was a guild law and they could be fined if they didn't follow it.
I guess that the soap and water mix also has a higher boiling point than water only.

If the Mongol bowyer was being truthful , and I beleive he was. You are gaining more than just a shaped horn by his method.

Boiling is cooking ,and cooking keratin breaks it down.

Milk is a glue in it's own right, not a bad thing to have soaking into your horns.

Water is the universal solvent ,and soaking and / or cooking your horns in water will dissolve some minerals and keratin out.So using a already saturated ,or highly loaded with supended solids ,solution instead of water should be beneficial.

Ralph,
Not all things are soluble in water. It is not a universal solvent. Keratin is a common protein which in the forms of hair and bird beaks spends a lot of time in water without be denatured. The purpose of boiling horn in water is to uniformly heat it. Direct radiant heat has a tendency to cause the surface to burn so it was worked out a long time ago that preparatory boiling could remove this problem.

I have boiled strips of horn and it has had no persistent effects on its mechanical properties once it had cooled down and dried. Perhaps experiments with strain gauges mights show some small change in its bending capabilities, but not enough to affect its performance in bow making.

Sometimes the reasons people do things have more to do with side effects than the stated purpose. Perhaps the Mongol practice has some other benefit in the particular circumstances where the bowyers are working.

Bede , well sure the idea of a true universal solvent was one of the dreams of the alchemists. But Water is taught to be the universal solvent in chemistry and biology classes in a more generally defined way . Google it.

What I'm really getting at though is thermodynamics and entropy .

http://dwb.unl.edu/Teacher/NSF/C11/C11L ... tropy.html

witch is in simple terms substances in solution will go from areas of high concentration to areas of lower concentration .( drop some dried granulated hide glue in water , and it dissolves evenly) This doesn't happen to a ducks beak because it is still alive. Put just a birds beak in water ,and give enough time the water will start to dissolve minerals out of it.

So what I do , is use water that is already super saturated , and I end up not needing to boil the horn at all . I soak them for a month or so , then heat the pot for about a hour .Till water vapor is just starting to come up .About as hot as hide glue. Then I can form the horn .

I have a easier time getting hide glue to bond well to the horn ,than I used to also.

Ralph,
The keratin in hair, horn and duck's beaks is not living. More keratin is produced by specialised cells. It is a protein noted for its chemical inactivity. Usually enzymes are necessary to break it down quickly or other other chemicals that attack the sulfur bonds.

I do not dispute that if you soak keratin long enough it will start to lose incorporated minerals, but I would be surprised if the normal methods used by bowyers sufficiently denatured it to affect its performance.

There are quite a few bow makers who write here and I would be interested in their experiences. This would be a good subject for a paper if some rigorous testing was done.

I did look at several papers on keratin dissolution before I wrote my comments.

Bede , I think I agree on most of your points , and a detailed study would be awesome.

We should try a quick test , like boiling some hair ,and see if it shrivels or changes weight after boiling. It would takes a pile of hair and an accurate scale.I think.

The part of the Mongol method that most intrigues me is that they don't have to heat the horn at all. Living in the mostly treeless environment that they do , may have caused them to develop the practice. As you suggested.


Ralph

A break test on a hair string , before and after boiling might be good too.
And soak a third string in old milk for a few weeks.

Hair is cheaper to play around with than horn.

I put some split gemsbok horns in a tub of milk for a month .Here they are tied down to a board ,straight out of the tub no heat added.

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And here they are today after drying .

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