working with horn

[fujimo]

any of you guys worked at flattening a horn- i have seen the guys use gemsbuck horns for bow bellies.
is it boiled
read that it needs to boil for six hours  

had a piece boiling for 4 now- still not that pliable in the mid section- not soft enough to clamp between two boards.
any ideas
thanks

[LittleBen]

I've heard of two methods. One is soaking the horn for long periods of time ... sometimes in milk ... don;t know why milk instead of water ... the other method I've heard is to use dry heat and lots of pressure like with a vise.

This thread might help,  http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=print_topic;f=40;t=000066

[LittleBen]

My take it this .. if it needs 6hrs of boiling, it's probably more about getting water soaked into it than getting it hot. I'd soak it for like a week or something and see if it softens enough, then clamp it between two hardwood boards to dry. If it's not softened after a week of soaking, boil it for 15min, then clamp it.

[fujimo]

thanks for the link Ben.
will try that!

[scars]

Soak it over night. If they feel dry or are old then use oil to heat them. PA has a great tut on how to prep horn to get the most out of it. you tube has an excellent video shows Thomas D Korean hornbows being made. The Korean bowyer uses a flatting jig that works real good. The horn is always visible and used with steam works great.

Personally I used my mill with a 5/8" rotary rasp to get the horn in the ballpark of about 1/8" to 3/16" thick. Then I use dry heat to flatten 3" to 6" at a time. You can get 3 horn strips per horn but it is best if you use two horns to mate the pairs. Fair warning Gemsbok is not as good as water buffalo. By that I mean in my opinion It has the same elastic quality but not the springiness on the return.

I noticed a mistake elastic quality should be compression.

[monterey]

It's about the heat.  Once water starts to boil, it can't get any hotter!  It will soften much faster if put into hot cooking oil no hotter than 320 deg.  It does not take long.  Experiment with short periods rather than just leaving it to overcook!

This I learned from a maker of powder horns who consoled me when I explained that boiling my horns im water was just not getting them soft eonough to work.  This is how the horners make the flat pocket powder horns and also how they round the large end opening to take a round plug.

[fujimo]

thanks guys- guess i will try the hot oil tomorrow,i just have some impala horns , i am trying to flatten.
thanks!

[fujimo]

anybody want any crispy fried horn chips!!!        
well that was my first experiment- but i ended up getting it figured out- tested some odd pieces- and ended up leaving them in there just too long- after the hot water experiment!!

but i figured after a few experiments, that by getting the oil up to about 350- then letting it cool back down, then with the stove off, putting the horn in , at about 320 ish or lower, and really, as monterey says, its real quick- maybe 20 to 30 seconds- take it out pry the horn openwith pliers, partially flatten it, re dip it, pry again, get it "flattish" then to the boards and the clamps.
now,  i'm off outside with my horns and blankie to go and find a spot to sleep    :D  
lets just say that the ol'gal... shes not so enamoured with my horn right now ...    :eek:      :eek:

[scars]

fujimo,

Your oil does not have to get above 212 degrees, keep it at 170 to 180 degrees. That gives you 10 to 20 minute bath depending on thickness of the horn. The higher the temp the more brittle it becomes when it cools. And the less times you heat it the more elastic it stays. Never put it in water to cool it off that also makes it brittle. Let it cool naturally. Remember it is the same stuff as hair, and you have heard the horror stories of burnt hair from the wifes.  

[Buemaker]

Will the oil not affect any later gluing of the horn?  Bue--.

[BigJim]

I seldom use pieces longer than 10"s and most around 5 or 6"s. I cut the pieces off the horn and then flatten with a heat gun and vice. Simple.

good luck, bigjim

[fujimo]

thanks guys, will try the even lower heat tonight on some other pieces- the two i did last night one come out really well( the one where the lower temp was used- yer absolutely right scars- thanks for the extra info mate:) )the other one with the higher heat, the ribs on the horn had got depressed- it was just too pliable- but this morning it was too brittle- overcooked!!
i believe if it is thoroughly cleaned with acetone Bue, it is gluable- i guess kinda like using heat and oil to straighten staves- and i have glued/finished afterwards.
going to use these for handle overlays anyway- so will let you guys know how it works out.

also gonna try a piece with the heatgun too- got some scraps, and will experiment with them!

thanks all.          

[scars]

fujimo
That's how I learned. I did a lot of web researches on horn bows, and there are a lot more than you would think. I ruined a couple of long pieces over heating them. Then I just started playing with the bad horn to see how they would react to different heating processes.

Bue,

Oil will come off with dawn dish soap don't need to use acetone. As long as the mating surfaces are flat then roughed up you will get a good bond.

[rainman]

Go into the the Build-a-long for a real good tutorial by John Sturtevant.  I followed his tutorial when I built my horn bow.