Advice needed for a Rookie!
Dear All,
Below is one of a pair of bows, that I have been working on since this spring. It is a 5 piece construction, maple, except for the ash handle, deer leg sinew back, and waterbuffalo horn belly. All of the glue is hide glue. Since we desired at least one working bow after our pains we opted to make something as close as we could to the 'Superb' of Saracen Archery. Hence the bow is deliberately assymetric, but due to the wiles of knot placement in the maple log, it is slightly more than I'd like. There are a few twists, but non-critical in magnitude. It has dried for 2 months before the intial tillering just done.
The problem that stops me shooting this, is a percieved fault in the sinew, at the point the ash handle piece is jointed to the upper limb. At the point of the wedge, and along the glue line there is a whitening of the sinew. At this point there was a slight imperfection in the joint's fit, perhaps a few mm^2 of gap, that was filled with glue. I guess therefore that the sinew is glued not so well there, and it is stressed, hence the whitening (caused by fractured glue). The other limb whitened (and cracked) slightly on the back, but not enough for my camera to distinguish.
Is this fault a problem? How should I address it?
My Thanks
Below is one of a pair of bows, that I have been working on since this spring. It is a 5 piece construction, maple, except for the ash handle, deer leg sinew back, and waterbuffalo horn belly. All of the glue is hide glue. Since we desired at least one working bow after our pains we opted to make something as close as we could to the 'Superb' of Saracen Archery. Hence the bow is deliberately assymetric, but due to the wiles of knot placement in the maple log, it is slightly more than I'd like. There are a few twists, but non-critical in magnitude. It has dried for 2 months before the intial tillering just done.
The problem that stops me shooting this, is a percieved fault in the sinew, at the point the ash handle piece is jointed to the upper limb. At the point of the wedge, and along the glue line there is a whitening of the sinew. At this point there was a slight imperfection in the joint's fit, perhaps a few mm^2 of gap, that was filled with glue. I guess therefore that the sinew is glued not so well there, and it is stressed, hence the whitening (caused by fractured glue). The other limb whitened (and cracked) slightly on the back, but not enough for my camera to distinguish.
Is this fault a problem? How should I address it?
My Thanks
I'd say wrap it with sinew, and shoot it some. If it seems to be stable you can later remove the wrapping if you don't think it looks alright.
It does look like the grip V-splice could have lifted a little, pressing onto the underside of the sinew, as you say. I'm not the expert here, but I would not be surpriced if it holds together for a long time even with a slight flexing of the splice inside the limb. The bow does not look to be overly stressed, so there should be some tolerance.
If the problem grows and you can see that the sinew is lifting from the core, I would consider pushing a thin syringe needle through the sinew layer to fill the gap with glue and then clamp/wrap the spot well. Taking off either parts of the sinew layer or the horn belly to get to the problem seems to me to be a little risky for such a minor problem.
Well, again, I haven't got too much experience with horn bows, so you might want to wait for more answers 8)
It does look like the grip V-splice could have lifted a little, pressing onto the underside of the sinew, as you say. I'm not the expert here, but I would not be surpriced if it holds together for a long time even with a slight flexing of the splice inside the limb. The bow does not look to be overly stressed, so there should be some tolerance.
If the problem grows and you can see that the sinew is lifting from the core, I would consider pushing a thin syringe needle through the sinew layer to fill the gap with glue and then clamp/wrap the spot well. Taking off either parts of the sinew layer or the horn belly to get to the problem seems to me to be a little risky for such a minor problem.
Well, again, I haven't got too much experience with horn bows, so you might want to wait for more answers 8)
Oh, and another thing: you might want to check if the spot has got some extra string follow that does not easily explain away by how the bow bends. :)
Thanks Kviljo, I'll fortify that section. I did wonder if the cause was excessive bend at that point, but it looks fine to my inexpert eye (even given the limbs are set forward at an angle at the handle).
Secretly, I was hoping that someone would say 'Oh that happens to me everytime, don't mind it'.
I shall post further if there are catastrophic results!
Secretly, I was hoping that someone would say 'Oh that happens to me everytime, don't mind it'.
I shall post further if there are catastrophic results!
Oh that happens to me everytime..
(and then it breaks)
:D
(and then it breaks)
:D
Shown are photographs of the sister bow to the one above. Since the limbs are slightly assymetric, I am again puzzled which tiller to be satisfied with. In the first bow, I tillered it to make the handle and string parallel, but there is a great deal of bend in the lower limb, and a lot of string follow. I think therefore, I might let the handle appear to be rotated a little with respect to the line of the string, to avoid overstressing either limb.
What are your more experienced opinions on the tiller?
The longer limb is a bit scarred on the horn, ideally it would be cleaned up a bit, which would probably require some scraping on the shorter limb, for balance.
Both bows will coated on the sinew side by some vegatable tanned leather.
What are your more experienced opinions on the tiller?
The longer limb is a bit scarred on the horn, ideally it would be cleaned up a bit, which would probably require some scraping on the shorter limb, for balance.
Both bows will coated on the sinew side by some vegatable tanned leather.
So, we've tried to apply the leather to the back of one of the bows, with no success. The leather will simply not stick! We cut the leather so that it would overlap the edges, and sit on the horn. The leather was a thin calfskin, that I spent a while scraping, so it's now between 0.5 and 1 mm thick. It was soaked in a thin hide glue, before a thicker glue was applied. Even using rubber bands, the leather wouldn't stick down on the edge and horn side of the bow.
We gave up when the sinew started to look soggy.
Does anyone have any advice on how to apply a leather cover to a bow?
We gave up when the sinew started to look soggy.
Does anyone have any advice on how to apply a leather cover to a bow?
use thin leather ( reindeer or kangaroo )
apply hot glue to the leather
apply hot glue to the bow
wrap the leather with tension to the bow back
heat the leather by rubbing where it does not keep contact spontaneously (siyah curves or so) and press down there until cooled
apply hot glue to the leather
apply hot glue to the bow
wrap the leather with tension to the bow back
heat the leather by rubbing where it does not keep contact spontaneously (siyah curves or so) and press down there until cooled
Interesting bows!
Where in England are you? I'm in County Durham.
Where in England are you? I'm in County Durham.