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Question about preparation of Ibex horn strips.

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Vonegelut
As you know from earlier post I've got an Ibex horns. So I cut them lenghtwise and got four strips (or two usable strips without a bumps)
I need advice for the next preparations (especially from you who had experience with such horns)?
Vonegelut
inner strip. Looks pretty twisted . The steaming or boiling are required
jack farrell
Rafael; I try to describe this technique also to those who are using sheep horns. You must not follow the flat plane of the outside of the horns but rotate that plane by 5 degrees or so. Then the horn becomes much flatter. In your picture, rotate the horn counterclockwise five degrees. Do you understand this statement?
Vonegelut

jack farrell wrote:

Rafael; I try to describe this technique also to those who are using sheep horns. You must not follow the flat plane of the outside of the horns but rotate that plane by 5 degrees or so. Then the horn becomes much flatter. In your picture, rotate the horn counterclockwise five degrees. Do you understand this statement?

Hi Jack! It's a bit hard for me to understand those things in english (wish you to speak Kz or Ru). But I will try!
Did you mean "not follow flat plane" in a case of straightning operation or what? Please, can you take my picture and show me what do you mean using some computer graphics ?
Ok Jack here I replaced the photo
Bede
Have you considered cutting the horn into narrow strips and gluing them to the core in parallel edge to edge? This was the technique used in Iran and some parts of Central Asia. Each strip is glued on separately so the process is easier, but it takes more time. The only problem is that it is best to wrap the limb with and waterproof the whole limb.
jack farrell
Rafael; You are holding the wrong side. You should work on the outside bend, the one with the knobs. Hold it with the point exactly down. In this picture the point is at 4 on the clock. Lower it to 6 on the clock.

Bede, the Persian technique is good for the leftovers.
Vonegelut

jack farrell wrote:

Rafael; You are holding the wrong side. You should work on the outside bend, the one with the knobs. Hold it with the point exactly down. In this picture the point is at 4 on the clock. Lower it to 6 on the clock.

Bede, the Persian technique is good for the leftovers.


Bede, I shall make a note to that technique if I will buy broken horns in a cheaper price.

Ok, Jack now I understood you! And put the right picture.
Bede
It works with narrow full length strips. I would be careful of broken horns in case they had invisible fractures.
Vonegelut

Bede wrote:

It works with narrow full length strips. I would be careful of broken horns in case they had invisible fractures.

Will pray it not to break.

So what the first operation I am gonna do now? Steaming , boiling for achieve a straight strip or remove the excess width, lenght ? Also question about the other 2 strips with big bumps - Are they still can be useful for bow belly or not? If not I can use it for other purposes.
jack farrell
Rafael; The piece with the big bumps is the good piece. This is called the outside curve. The reason to cut the horn thick is because it is difficult to see the piece of horn that you want to finish with.

The final base of the horn slat which you will glue to is level with the pencil, not level with the mass of horn. With the horn tip down at 6 on the clock, the base of the horn slat is at 90 degrees to the horn.

Is this understood?
Adam Karpowicz
As Jack said, the pieces from outside of horns with big bumps are the pieces to use for your bow.

1. Take the pieces with bumps and sand, grind or file down the bumps. All cracks or defects in horn must be sanded to solid horn. After filing, the surface does not need to be flat. The surface can be round a little, because most bows have round belly - the sanded surface will be the belly of your bow.

You will cut the strips off these pieces next. Mark the thickness of your strips on the sides of the pieces (1-2mm thicker than planned for the bow).

2. Glue the pieces to plywood with hot-melt glue, so they are not moving at all. The pieces are a little twisted, so decide how to position the pieces to get the length and thickness of the strips for your bow. Then cut off the strips with a bandsaw. This way you will not be following the twist of horn.

If you cut by hand, DO NOT FOLLOW THE TWIST OF HORN. Cut so that the strips will be long enough and not twisted. It is not possible to un-twist horn.

Look at pages in my book. There is an article on ATARN about cutting horns as well.

Adam
jack farrell
OH, OH ! Adam. I want him to do this a different way because there is very little usable horn in an Ibex. Even a small miscalculation will result in ruining these horns.
Adam Karpowicz
Jack - there is a lot of solid horn in these pieces. For a Turkish bow he probably does not need a full length anyway. Besides, I wrote: "position the pieces to get the length and thickness of the strips for your bow". This is enough for him to figure out how to cut. Let's not complicate it too much.

Adam
jack farrell
I will defer to you all things about a Turkish bow but if he follows your instructions, he will not get a usable horn slat. The usable horn is very thin. I want him to approach it in the opposite manner. This is why I had Rafael cut the horns which he did correctly.
jack farrell
Rafael; What tool did you use to cut the horns in half? Did you cut by hand or with a machine?
Vonegelut

jack farrell wrote:

Rafael; What tool did you use to cut the horns in half? Did you cut by hand or with a machine?

Sorry for some stupidity :oops:
Firstly thank you very much Adam for reply my message!
Ok now I think I understood you right. So the useful side of horns are with bumps! But what about the inner strips?
Ok I will file down the bumps firstly & then put the fotos on ATARN (step by step all my operations)
Vonegelut

jack farrell wrote:

Rafael; What tool did you use to cut the horns in half? Did you cut by hand or with a machine?

Jack as no possibilities to by a hand bowsaw or whipsaw (if my translation is right) Cause I didn't find it in our markets. I've used a electric fretsaw( you can see it on my previous post) I found out that's good for that purpose ( but with good quality blades for cutting metal)cause I've broke 6 of russian blades on one horn. So I decided to use German Bosch & it didn't broke during the whole process. The depth of cutting was 85mm .
What do you think can I use angle grinder to filing down the bumps?
Vonegelut

Adam Karpowicz wrote:

Jack - there is a lot of solid horn in these pieces. For a Turkish bow he probably does not need a full length anyway. Besides, I wrote: "position the pieces to get the length and thickness of the strips for your bow". This is enough for him to figure out how to cut. Let's not complicate it too much.

Adam

Adam & Jack here Ive made some measurements too
Vonegelut

Vonegelut wrote:

Adam Karpowicz wrote:

Jack - there is a lot of solid horn in these pieces. For a Turkish bow he probably does not need a full length anyway. Besides, I wrote: "position the pieces to get the length and thickness of the strips for your bow". This is enough for him to figure out how to cut. Let's not complicate it too much.

Adam

Adam & Jack here Ive made some measurements too

Vonegelut

Vonegelut wrote:

Vonegelut wrote:

Adam Karpowicz wrote:

Jack - there is a lot of solid horn in these pieces. For a Turkish bow he probably does not need a full length anyway. Besides, I wrote: "position the pieces to get the length and thickness of the strips for your bow". This is enough for him to figure out how to cut. Let's not complicate it too much.

Adam

Adam & Jack here Ive made some measurements too

Vonegelut

Adam Karpowicz wrote:

As Jack said, the pieces from outside of horns with big bumps are the pieces to use for your bow.

1. Take the pieces with bumps and sand, grind or file down the bumps. All cracks or defects in horn must be sanded to solid horn. After filing, the surface does not need to be flat. The surface can be round a little, because most bows have round belly - the sanded surface will be the belly of your bow.

You will cut the strips off these pieces next. Mark the thickness of your strips on the sides of the pieces (1-2mm thicker than planned for the bow).

2. Glue the pieces to plywood with hot-melt glue, so they are not moving at all. The pieces are a little twisted, so decide how to position the pieces to get the length and thickness of the strips for your bow. Then cut off the strips with a bandsaw. This way you will not be following the twist of horn.

If you cut by hand, DO NOT FOLLOW THE TWIST OF HORN. Cut so that the strips will be long enough and not twisted. It is not possible to un-twist horn.

Look at pages in my book. There is an article on ATARN about cutting horns as well.

Adam


Adam is there any possibilities to make straight the twisted strips using boiling,steaming & clamping in the forms?
Adam Karpowicz
No, you can not make twisted strips straight. You need to plan very carefully how to orient the cuts on the horns. The strips must be wide enough for your bow and long enough. A Turkish bow can be made with strips that are only 3cm wide (even less sometimes), but the strips must be straight so they fit on the wooden core of the bow. (here you why your strips can not be twisted - twisted strips will be crooked on the core and will not cover the whole length of the bow's arms). Try to plan the end (not the butt) of horn to cover the grip of the bow.

If you can not cut flat strips that are wide enough to cover the bow, you can cut the strips curved in cross-section (concave). Such strips can be flattened a little with heat to make them wider, but the flattening is not easy and is better avoided.

If nothing works, you can use curved strips (but not too much) and glue them onto curved wooden core (curved in cross-section - convex). Look at pictures of original bows' cross-sections. This method may be very difficult if the horn has thin walls.

Adam
Vonegelut

Adam Karpowicz wrote:

No, you can not make twisted strips straight. You need to plan very carefully how to orient the cuts on the horns. The strips must be wide enough for your bow and long enough. A Turkish bow can be made with strips that are only 3cm wide (even less sometimes), but the strips must be straight so they fit on the wooden core of the bow. (here you why your strips can not be twisted - twisted strips will be crooked on the core and will not cover the whole length of the bow's arms). Try to plan the end (not the butt) of horn to cover the grip of the bow.

If you can not cut flat strips that are wide enough to cover the bow, you can cut the strips curved in cross-section (concave). Such strips can be flattened a little with heat to make them wider, but the flattening is not easy and is better avoided.

If nothing works, you can use curved strips (but not too much) and glue them onto curved wooden core (curved in cross-section - convex). Look at pictures of original bows' cross-sections. This method may be very difficult if the horn has thin walls.

Adam

Ok, Adam. For now I have two pairs (rough laths) that will stay to dry till May or June (one were bent in January the second about 2 weeks ago) Also one pair is more rounded from a small diametr(14cm) tatar maple trunk, another one is from black locust larger diametr(about 25-28cm) . I have the buffalo horn 3 flat strips (2strips are - 40cm long & another one 25cm) This horns were a friendly gift from our one of our Atarnities & my friend Dr. Uli Wellner. He send them to me before i found an Ibex. And I am really thankful for him!
So what do you think is it a good idea to make the a bow with a rounded limbs (core from tatar) using Ibex horns and their concavity form? And buffallo's for black locust more flatten shape?
The bows that I've planned are 47 (tatar core) & 48 inches (black locust) long. So According your book = the final lenght of the first bow will be - 21,5 inch, & for the second bow - 22inch. So I am thinking whether or not will be the lenght of the Ibex horn strips for 21,5 inch long limb....
P.S . Can you take a look at my other publications about bending a wood.
Thank you for Advance!
Rafael
Adam Karpowicz
For a 48 inch nock-to-nock bow:

The length of the tips is 2 x 3 inches = 6 inches (I assume the tips will be 3 inches each). Then the limbs to be covered by horn are: 48 - 6 = 42 inches. Then you need 42 / 2 = 21 inches each strip of horn. Add 1 inch at the ends to have something to clam when groovng etc. = 23 inches per strip. This would be a comfortable length of each strip of horn. Before glue-up, you would trim 1 jnch off the ends.

The 40cm strips you have = 16 inches. It is not enough for a bow that long. You can glue the strips so that 3 inches of kasan under the tips is not covered by horn. Then you still need 21 - 3 = 18 inches (plus 1 inch at each end = 20 in). You need longer horns or make a smaller bow.

The laths you bent look OK. The angle between kasan and sal maybe a little too sharp for a first bow.

Adam
jack farrell
I prepare the gluing surface of Ibex slats first as a maximum width above the horn hollow. Then the face of the belly is worked out rough removing bumps, cracks ant blemishes. There is only just barely one slat thick and by starting on the belly face is to throw away the slat.

I find the belt sander placed in a vertical jig to be a most useful tool for making all types of bows.

PS.I could not have made a Scythian bow if it were not possible to heat bend horn.
Vonegelut

Adam Karpowicz wrote:

For a 48 inch nock-to-nock bow:

The length of the tips is 2 x 3 inches = 6 inches (I assume the tips will be 3 inches each). Then the limbs to be covered by horn are: 48 - 6 = 42 inches. Then you need 42 / 2 = 21 inches each strip of horn. Add 1 inch at the ends to have something to clam when groovng etc. = 23 inches per strip. This would be a comfortable length of each strip of horn. Before glue-up, you would trim 1 jnch off the ends.

The 40cm strips you have = 16 inches. It is not enough for a bow that long. You can glue the strips so that 3 inches of kasan under the tips is not covered by horn. Then you still need 21 - 3 = 18 inches (plus 1 inch at each end = 20 in). You need longer horns or make a smaller bow.

The laths you bent look OK. The angle between kasan and sal maybe a little too sharp for a first bow.

Adam

Ok. Thanx for some calculation Adam:-)) But if I use all 3 strips in a such way glue to core for a 48 inch bow? Is it safe or not?

P.S Thanx for my cores! Can I weaken the clamps pressure at the end & to open a bit a kasan gozu?
Vonegelut

jack farrell wrote:

I prepare the gluing surface of Ibex slats first as a maximum width above the horn hollow. Then the face of the belly is worked out rough removing bumps, cracks ant blemishes. There is only just barely one slat thick and by starting on the belly face is to throw away the slat.

I find the belt sander placed in a vertical jig to be a most useful tool for making all types of bows.

PS.I could not have made a Scythian bow if it were not possible to heat bend horn.

What do you mean Jack "I prepare the gluing surface of Ibex slats first as a maximum width above the horn hollow." ?? Is that means that you start from the side where the bone was?
I have only the final sander not the belt sander . I realize that I need some upgrade of my workshop as buying belt sander & bandsaw..
jack farrell
Yes, with Ibex you must start with the side where the bone was and create a flat surface which is at 90 degrees to the horn. It is not really possible to plan the bow until the horn slat is ready. It must be carved out and a band saw is not really that helpful for that step. You can use a rough rasp and your sabre saw to do the work.

Adam why can he not just do rough non matching grooving to conserve on horn length?
Adam Karpowicz
I am not sure why this has gotten so complicated. The cut slats can be flattened by heat to make the horn's cross-section flat. Or, better yet, the concavity (in cross-section) can be opened a little to make it curved to fit a curved (convex) core. The solid part of horn would in this case be carved down to make it convex a little as well - identical along the whole length of the strips. I do not see the need to make matching grooves (although it is possible in convex horn just the same). I still like to add an inch to the ends to have something to hold on to while working the horns.

BTW - you can flatten the straight-cut strips with heat as above, but correcting twisted strips is not going to work, since they will reverse eventually on the bow and the bow will be twisted as well.

Raphael - the three pices as you show can work on the bow for a few shots, but the bow will not be durable. The horn will keep delaminating there with each shot or rather fast if the bow sheds its string. On the other hand, since this is your first bow, then it may be the best solution for now to practice the technique. The bow would have to be wrapped with sinew at the joints of horn. Have you read the chapters in my book? I have a feeling I am repeating myself.

Adam
Vonegelut
Dear Adam sorry for some tediousness, but the reason I asked you about three horn strips joint is - I saw a Crimean tatar bow made this way by my friend Ulrich. So that was a bit tempting for me. But I have time to think what way is the best to do, till my cores are drying.
Ofcourse I read chapters in your book & I am always repeating them for better understanding & I've just reached chapter about horn & core preparations. And it's the process of learning & teachers in my country like to say to their students - "Повторение - мать учения" (eng. "process of repeating is the Mother of learning. Who can I asked here in Kz about the bowmaking ?? - Nobody. We lost this beautiful art hundreds years ago. It's amazing to have such wonderful resource as ATARN & such teachers as you, Jack & others members.

P.s I will have a free time on the next week & work with Ibex horns & then show you