Horn to core glue question
I have just finished the grooving process of core and horn on my first hornbow. Currently i'm pondering which glue to use. I have some rabbit skin glue which is very quick to gel, I also have a lot of sinew scraps to make sinew glue and will be making hide glue from dog chew rawhide tomorrow.
I think if I make some hide and sinew glue then they should be fine for he core/horn joint. I am hoping that they will have different enough geling properties. Or should I just mix the sinew scraps and rawhide together and make a hybrid glue? Also I seem to remember Adam advising against rabbit skin glue due to it being fatty? I don't have the book to hand at the moment...
I think if I make some hide and sinew glue then they should be fine for he core/horn joint. I am hoping that they will have different enough geling properties. Or should I just mix the sinew scraps and rawhide together and make a hybrid glue? Also I seem to remember Adam advising against rabbit skin glue due to it being fatty? I don't have the book to hand at the moment...
I've always wondered why not just use isinglass? I did experiments with wood and horn, and got very good results.
Maybe because is about 500 euro one kilo?
ginni
I agree with you. isinglass is expensive. but only if the price is the reason? I find no response so far :roll: . if one makes many bow - have to seek a cheaper alternative. but if you do several bow (as most of us) I think you should use the best materials. bowmaking is expensive pleasure :wink:
I agree with you. isinglass is expensive. but only if the price is the reason? I find no response so far :roll: . if one makes many bow - have to seek a cheaper alternative. but if you do several bow (as most of us) I think you should use the best materials. bowmaking is expensive pleasure :wink:
similar question: why not use gelatine ? its pure collagen.
I found rabbit glue very strong
I found rabbit glue very strong
Well i've just finished making my sinew glue and am going to use it as is for the horn to core joint.
However i'm a bit confused about the way Adam works out the concentration of glue to use.
I have reduced the sinew glue down to the 30 percent concentration (syrupy thickness!) that is recommended.
So for sizing the horn and core I have decided to do it the Turkish way eg. 3 coats of glue at 10 - 15 %, letting them dry for a day then using glue at 25 - 35% for the actual gluing.
My question is do you make the mix (eg. 10%) using the 1 part of glue to 9 parts water? Also do you measure the water and glue by weight or by volume?
However i'm a bit confused about the way Adam works out the concentration of glue to use.
I have reduced the sinew glue down to the 30 percent concentration (syrupy thickness!) that is recommended.
So for sizing the horn and core I have decided to do it the Turkish way eg. 3 coats of glue at 10 - 15 %, letting them dry for a day then using glue at 25 - 35% for the actual gluing.
My question is do you make the mix (eg. 10%) using the 1 part of glue to 9 parts water? Also do you measure the water and glue by weight or by volume?
As the specific gravity of glue is around 1, it doesn't matter whether you use weight or volume.
The exclusion of air bubbles is very important. The components will need to be very warm (but not allowing the glue to cook) when placed together. The Chinese press used for this process has the quality of exerting the greatest pressure in the middle so that any bubbles are squeezed outwards. I suggest pressing the component from the centre before binding, which will exert pressure from the side inward. The grooves will increase surface area; but they will also prevent the components from sliding laterally as you apply pressure on them with a generous layer of glue between.
S
The exclusion of air bubbles is very important. The components will need to be very warm (but not allowing the glue to cook) when placed together. The Chinese press used for this process has the quality of exerting the greatest pressure in the middle so that any bubbles are squeezed outwards. I suggest pressing the component from the centre before binding, which will exert pressure from the side inward. The grooves will increase surface area; but they will also prevent the components from sliding laterally as you apply pressure on them with a generous layer of glue between.
S
Why not the Japanese Yumi way "all wrapped in bowmaking". You won't get any bubbles
http://198.170.107.188/phpBB2/viewtopic ... ght=wedges
R
http://198.170.107.188/phpBB2/viewtopic ... ght=wedges
R
Thanks for all the help guys - its appreciated!
Stephen I was planning on laying a length of rope along the center of the horn before wrapping to exert more even pressure. My horn has a flat belly at the moment.
I really like the'wedges' method. I am definately considering using this method now as I have a lot of scrap bamboo at the moment. I like this idea because I can see how it would be easier to do the whole process without imparting any 'twist'.
Well I've finished applying the sizing coats of glue to the horn and core so i've got a day to decide which method to use....I also have enough clamps but I don't want to put them out of commission for a month!
Stephen I was planning on laying a length of rope along the center of the horn before wrapping to exert more even pressure. My horn has a flat belly at the moment.
I really like the'wedges' method. I am definately considering using this method now as I have a lot of scrap bamboo at the moment. I like this idea because I can see how it would be easier to do the whole process without imparting any 'twist'.
Well I've finished applying the sizing coats of glue to the horn and core so i've got a day to decide which method to use....I also have enough clamps but I don't want to put them out of commission for a month!
Mike; I like to assemble dry several times to get a feel of how it will go. You could add a layer of plastic bag to prohibit possible adhesion during a trial.
Koreans build up the glue through many coats. The setting up of the glue only takes a few days. It then cures for some time. No need to clamp for a month, I think.
Reto, Yours is a very clean powerful technique. Plenty of space to check the glue line.
Koreans build up the glue through many coats. The setting up of the glue only takes a few days. It then cures for some time. No need to clamp for a month, I think.
Reto, Yours is a very clean powerful technique. Plenty of space to check the glue line.
I've decided to try the bamboo wedge method - I just really like the look of it, nice even pressure and seems at first glance to be quite a simple ethod!
Jack - yes I certainly intend to do a few 'dry' runs especially as this is my first hornbow. Hopefully all goes well.....
Jack - yes I certainly intend to do a few 'dry' runs especially as this is my first hornbow. Hopefully all goes well.....
I used the wedge method and all went very well. I used sinew glue with a touch of added rabbit skin glue. I really liked this method as I could see the glue line very well whilst it was gelling and it was good that I cound see it as I had to 'fill in' a few spots and add to the fillet. How long do you guys leave a freshly glued core before fitting the teplik?
24hrs is enough
Sorry for all the questios! My core has had about a week to dry so far and i'm going to fit the teplik in the next couple of days. However i'm just wondering how long you need to leave the core / horn clamped for? Obviously it would be easier to fit the teplik without the rope etc in the way.
Mike; maybe Turkish terminology is getting in the way. Tepliks are formers used for the final conditioning and stringing of the bow. What I think you mean is the celik (sp); the spacer in the grip? I think it is not yet time to do this. You are still going to bend the limbs as sinew is added, or maybe not?
At any rate the glue for the core/horn will cure for a month before proceeding. The cords may be removed after several days. Do not bend yet. Adam should advise. Do you have his book? Are you making a Turkish bow?
At any rate the glue for the core/horn will cure for a month before proceeding. The cords may be removed after several days. Do not bend yet. Adam should advise. Do you have his book? Are you making a Turkish bow?
Hi Jack, oops my mistake! Yes you are correct - I meant the celik! Thank you for the information. I will fit the celik tomorrow and then leave it alone for a further 3 weeks.
I was planning on bending the limbs into more reflex when the core is shaped and ready for the sinew. I will be doing this as Adam says in his book (yes I have a copy) eg. apply sinew, let it gel and then bend into more reflex. Oh and yes I am going for a Turkish warbow style of design.
My horn strips are 5mm thick, does anybody have an estimation of draw weight? I know draw weight is also affected by the thickness of core and sinew but any rough ideas? After reading about the efficiency of the lighter weight bows I decided to go for thicker rather than thinner!
I was planning on bending the limbs into more reflex when the core is shaped and ready for the sinew. I will be doing this as Adam says in his book (yes I have a copy) eg. apply sinew, let it gel and then bend into more reflex. Oh and yes I am going for a Turkish warbow style of design.
My horn strips are 5mm thick, does anybody have an estimation of draw weight? I know draw weight is also affected by the thickness of core and sinew but any rough ideas? After reading about the efficiency of the lighter weight bows I decided to go for thicker rather than thinner!
mike are you saying light weight composites are inefficient?
Yes, most of them worst than all wooden bow same waight./of course very good wood bow /