240's sheep horn bow build with Tom Lucas

[wizardgoat]

Once your at the final stage tillering, it takes less than 5 seconds with a heat gun  to get what you need.
There’s a lot of bridges to cross with building these bows, cross them as they come or the whole process can seem very intimidating.
I’ve never soaked my horns, just boiled for 10 minutes and strapped it down to a form.

[loefflerchuck]

Ryan, I start with mine as thick and wide as I can before flattening them to cut the straightest section I can later. Like Shelton's size in his photos. If I don't soak that size it will not soften.

Shelton, it's important to use really good glue. You can make it yourself with clean sinew scraps cooked in water 120-140f for 6-10 hours covered. You add just enough water to just cover the sinew.  Hide glue forms more complex bonds over the course of a year+. If you use heat to adjust tiller it is important to let those bonds form for 6 months oor the sinew may slip. I don't use a heat gun. A electric burner or heat pad works better. Heat it slowly to penetrate the horn without making it brittle.

[NorthHeart]

You two men are giving me some extremely valuable advice, and it is highly appreciated.

I got some sinew scraps on the way from the trade section of this forum.  Chuck, why do you believe that sinew glue is the best way to go vs. glue made from hide or Knox gelatin?  Whats the difference i thought it was all the same stuff.

I just bought a used burner today(large flat type roughly 12"x20").  It adjusts 225 degrees up to 425.  Would 225 degrees be ideal for the horn, and to clarify are you saying to lay the horn/sinew bow on it or just horn?  And im still hoping you will confirm if you do all the initial steps discussed in your previous post in only 5 days time with no issues "giving back" or re-twisting of the horn.

I also bought a used crock pot today for making sinew glue:)  And a huge pan that i hope will fit my next set of horns...Chuck

[NorthHeart]

Today my horns are soft enough to bend.  We clean the glue from the inner area now that is soft with a concave chisel.  Tom demonstrates how to bend the horn so you can tell its ready, and he uses his pocket knife to show how soft it is.  If your new to horn bows as i am, this is the only way i can explain it, at first its hard as concrete, after soaking it has the consistency of rubber...its mind boggling i had to bend the horn 20 times before i mentally accepted it wasnt going to snap in half.

I get the privilege of having Toms help while i lash them down.  We us the methods mentioned previously to accomplish this.  Now they will sit by his fireplace indoors for about a month.  The next step will be to narrow the horn to bow dimensions and then to splice them together.

[NorthHeart]

See my hand in the pic.  Promise i did some work this time not just watching.  In fact i lashed all the horn with a bit of help holding it down and tying knots courtesy of Tom.

[hoosierf]

Great build along. Thanks so much for the investment of your time. I see that the horn is lashed down with what will become the back up?  Any reason for that orientation?  I would have guessed you would be able to get it flatter with the belly side up.  Thx

[loefflerchuck]

As far as the memory of the horn and some twist coming back the answer is sometimes. Some horns stay straight and some retwist. After the first straightening I find where the bow lays in the horn and cut that out. Then remove some twist with a table sander to try and get it as straight and flat as possible. Then reheat and shape the bow again.

You don't want to put the horn or sinew on a burner. Hold it above always moving it to slowly heat it for a few minutes.
Ryan is just braver than I am using a heat gun. I heat slower just in case.

For homemade glue sinew is just easier as hide scraps are kind of greasy. I once only had a small amount of my glue and mixed it with knox and it worked well. Making glue is pretty time consuming. I also buy it. The best I have found is from Brooklyn Tool and Craft. I can't put a website here but you can look it up. I get the 315 g strength but have been told the lower GS glue is just as strong and some prefer it. Any half ass hide glue will work on wood for sinew backing but horn does not accept glue like wood and also bends further so is under more stress. The best glue should be used for the first layer on the horn. The next layers are bonding to sinew and stick easier.

[NorthHeart]

Great build along. Thanks so much for the investment of your time. I see that the horn is lashed down with what will become the back up?  Any reason for that orientation?  I would have guessed you would be able to get it flatter with the belly side up.  Thx

There is one thing i can come up with.  The cross section of the horn naturally slopes down at each side.  By lashing it with this side "up" (which will be the back), the rope can pull down on the sides and flatten the curve a bit.

[wizardgoat]

My last horn bow probably had 15-20 small heat gun sessions, and very little horn removal.
I use the low setting on my gun, and it literally take 3 or 4 seconds to get what you need.
I only aim it at the horn, and gently flex it as I heat it. As soon as I feel it give a little I clamp it down.

[NorthHeart]

No work could be done on the horns this week as they continue to dry naturally.  I did stop by Toms gallery and had a look at a few pieces that were being put back into the display case from a recent photo shoot.  I bought his biography, and as i learn more about his life it makes the privilege of learning the horn bow from him even greater.  Ill be Montana bound at the beginning of April.  If i am very lucky (and the horn cooperates) we might even have sinew on the back.  We shall see.

[NorthHeart]

Just a recap, i'm working on 2 sets of horn bows for myself.  Some of the pics are of a third set that Tom is building for a customer.  My large horns soaked for 14 days and were then strapped to a board.  My smaller set soaked for only 9 days and were strapped down.  For 25 days we let them dry near a fireplace in Toms care.  Without the fire you may wish to go a bit longer just to be safe. 

Next we cut the edges off the horn, leaving us with the bows limbs.  Tom prefers to lay a measuring stick down the center and mark with a pencil down each side, leaving approximately 1-1/8" wide limbs.  He prefers to cut outside the lines to be safe using his bandsaw.  I do mine, and go "extra safe" leaving them 1-1/2" wide.  I got them thinned down in thickness somewhat comparable to his.  He likes using a rasp.  Im a bit more comfortable with a belt sander, being very careful to leave extra material until he can check my progress.

[NorthHeart]

cutting and thinning....

[NorthHeart]

A good days work.

[DC]

At this point, they look to be 1/2" thick, can you bend them by hand, over your knee? Do they bend at all?

[NorthHeart]

DC-they are still quite stiff and i would be afraid to try and bend them on my knee at this point.  But they do flex a bit when you rasp over the part hanging over the edge of the vice.

Today another session of thinning, to remove the inner "flaky stuff", and to match the outer surface accordingly.  They are getting close to the point of being ready to splice.  Tom gave me the option to leave the tips natural or wack them off.  I told him i never built a horn bow before and for him to decide.  He said they just get in the way and hang off the end, this is because we will be using the thicker part down away from the tip for our nocks.  Tom has had bows in the past where the tip was too thin and when shot the string flew past the limb and "debraced" the bow.  I looked at a picture of one of his earlier bows where he left the tips full length, and then sinewed horn pieces on each side near the tip to essentially widen the limb and prevent this.  Ive also seen sinew wraps made into donuts to accept the string loop, and i imagine one could just keep wrapping the area in question to make it thicker, but with that also comes more mass near the tips, by cutting the tips off we remove mass.  In the end i told him these are "Tom Lucas" style bows.  We cut off the tips.