First of all i want to apologise for any grammar mistakes, and any other mistakes in writting caus i used google translate to translate all text that you will see here ( English is not my native languge so i wrote all in my languge than translated it ). I will trie to fix all things that are not translated , also dont laugh if you read onion instead of bow beacus in my country they mean same thing, also acacia caus google translate is mixing it with black locust. Well lets start .
As we know (primarily based on the experience of our ancestors) black locust is extremely durable wood, in every sense: solid, hard, Non-susceptible to decay and insects, long lasting and tough. On that basis by many as a perfect wood for bows. The answer is there somewhere in between, yes and no. Black locust tree is very specific in terms of bow's, because of the special way of making and because of the mechanical properties of wood. I'll try to explain in this tutorial that details in the process of development can be or/and are critical points in it that need special attention.First, to clarify the properties of black locust wood .... Wood species vary in compresional tension and endurance. Example: If you take a piece of wood in the shape of the rod and bend it into a semi-circular outer part of his suffering, increasing its length stretching and compression of the inner and reducing their length. This phenomenon is happening at such a small scale that is invisible to the naked eye but it is a crucial factor in making bows. If the piece of wood we continue to bend the will inevitably come to a permanent deformation of the play. What happens in a kind of strong tension (most sawmills): As their name suggests, their fibers better than stretching suffer compaction. Because the outer part to withstand bending but on the inside to collapse, ie. compressing because the wood fibers are not as able to withstand compaction, compression. With heavy compression types (mainly conifers) are going the other way around: since the fibers are more resistant to compaction it will stand on the inside of the suffering compaction but will break a piece to the part that suffers stretching outside. Very rare species collapse at the same time, are equally strong and compression and tension. The most imbowsant factor here is the thickness of the piece that moves: 1mm thick sheet of veneer can bend the roll and not crack because the thin, but with increasing wall thickness increases the problem that we're talking. The first picture explains this current exhibition.
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Step 1: Introduction
This introductory part is not only important for the development of bow's below have to understand the essence of the bow's: Wood shall in no way be overloaded because it will break.Where is all this locust? He has very good compression, the fibers well suffer compaction. But the tension is even better so that experimental piece still hurt by the compression of fibers. The only solution (except for the few exceptional situations) is to hold a piece of black locust as bow, thin and wide, to reduce the negative effects of compression on the belly of fiber ports. Black locust also has another problem (in a row) that will always inflict bowyers problem: if too overwhelming the fibers of the stomach, if we compress them too much will be irreversibly damaged, and this will be evident in the form of stretch marks on the cross piece. For other types of fibers are more or less recover if press piece too, but at a certain place at Locust he does not forgive mistakes when making such a different kind. One of the first tips: press not too many pieces, the motion must be spread on the entire length of the working harbor.Making a play for the port must be sufficiently dry. It is understood that about 10% moisture wood. It can be measured by carpenter moisture meter (unreliable method determines the most part wood surface moisture) or holding a piece of black locust in the area where the humidity is 55% and the air temperature is 20-30 C (operating with the U.S. Institute for wood) until you stop losing weight (weight control digital kitchen libra ). Black locust should be split before drying or hatchet and other tools of awareness to the approximate dimensions of the port to be dried as soon as possible, DO NOT REMOVE BARK! We can expect a dry piece somewhere in a month, a story of many years of drying the ordinary fiction, because libra is that tells us everything. One of the most optimal design for bow black locust is pyramidal. What does that mean-bow has a narrow handle and a non-working, thick enough not moving and narrow enough to be comfortable to grip. Handle is made from a light switch on the arm of the future port-they should be in the final state of at least 5 cm wide. Means that the rough shape before drying can leave them at 6 cm wide, we reduce the rest when it starts production. Length with handle day-to-spoke crossings could be about 20 cm. The total bow length should not be less than 1.7 m. Short tapering directly from the widest part of the areas that should be no more than a wide 10-12mm in final form. Because of their shape and are therefore called pyramid bow. One of the advantages of the pyramid bow is its nearly constant thickness of the arms (we explain when we get that far).When the piece is dry first stage is peeling. It is easily removed by knife . Coarse tore it to pieces. I say rough-no need to be too careful in tree bark (unless no nodes) as the first layer of wood under the bark, sapwood, waste from the game: a few sapwood rings and only have a pith beneath it that we need to create port . Around the node we remove sapwood maximum caution.
Step 2: Taking of Layers
Few people work (make) bows out of locust sapwood as its always because of poor quality and is not as durable as heartwood. White colored part, we have to take off the first ring but with that we should trie not to damage rest because at that point bow likely to break.
This is another limitation in locust: whereas in other species just take off the bark , and we back of the bow , and we have the locust sapwood. She takes off in long thin strips being careful not to damage the pith. If it is too thick sapwood, we see that there is a lot of work, it's the first we reduce by ax Keser (adze) ( wood chisle??!?!) dont know for the correct word for this tool
The picture shows what you need to follow, best of all, it has the fattest autumn zone
When you take off the sapwood port reduction approach to the sizes if you have not previously done so
When you take off the sapwood port reduction approach to the sizes if you have not previously done so.In locust is important to be careful not to shut up because it tends to clogging. I usually do this surgery with axe (in this case keser) , rarely with knife . As we approached quite close to the required dimensions continue to further reduce crude scalpel (to clog it and do not break tree nodes, we have less work using files). It is very important that the edges are not sharp bow, ideal roundness is to be shaped roughly pea. While working on this piece we encounter unexpected difficulties: three dead node, fallin out one. Depending on the position of the change and its threat to the bow. A node that is located at the middle branch is almost harmless, just clean it and leave a hole in the handle of the node is potentially dangerous, we look to be removed during the operation.
Most dangerous of all is the node-edge have no way to patch it. It has to be removed when folding and Tillering as a major threat to the bow.
When we reduced the dimensions of the piece to check if port axis goes right across the middle. It is not good that the axis deviates from the environment, especially in the handle, twisting makes the port in hand when at full draw a lot on the security, accuracy and performance of the port. In this case we see that each arm yourself right (no need to correct) but the bow fault in one point, hanging in there, and that must be corrected.
Correcting by steaming the wood. To handle this size is strong enough for an hour of intensive steaming . During the steaming time does not count during heating of water, but most gushing steam. The figure shows a simple enough setting for mating port in one spot. Patch is used to slow down and keep going steam temperature constant. Since wood is somewhat thermoplastic (can partially change shape when heated) heated wood will warp into the desired shape.
The wood is placed in the position of steaming immediately so that heated water and steam at the beginning of the release, and it warms gently to avoid splashing. We must regularly check amount of water and we must keep filling it with water but not to stop it boiling. After an hour extracting timber and put in the position of already prepared for the distortion.
That leaves him one day, to cool and hardened into a new form and return the moisture lost by heating (wood steaming almost always loses water and not receiving it). We put it in clamps that is more than necessary because wood tends to return to its original shape. Because twisting 30% more to be desired, when I remove the clamps from the piece back 30% of its original position, and we are where exactly should be (this relationship was not always like this, sometimes we blame more or less, depending on the situation).We see that after cooling everything is in place.
We approach phase of the tiler (setup looks bow). Smoothes the edges, reducing the amount of wood where the excess obvious. As we said, the pyramid of the bow is a mitigating factor that the thickness does not vary much-I bow moves at a constant thickness as it narrows looking frontally.
For bow used as an example of the need of some thickness of about 12-13mm (based on previous experience) throughout the length of the part with minimal adjustments. We check how thick it's convenient (in my case, usually the fingers, by feel). One of the guiding this process and the rings on the belly port. Should look similar to this: that the entire stomach is almost one growth ring , possibly two
What it means: the whole arm has (so to speak) the same thickness. Reducing wood is mostly done here by file and sandpaper as this piece a lot of choking. When reduced to the same thickness test whether a piece is moving. In this case the motion is strong and has met a requirement to immediately put the string. The moves to the desired force and follow bow's appearance (which is moving and where it stiff). This bow is pretty well balanced from the start, you have to ease up on the lower arm closer to the handle.
Here's an idea how little it takes to remove wood in this final phase: as the thickness of the removed layer of paper was more than enough to balance and adjust the port layout. (As we said, the pyramid bows are easy to tiller because of the same thickness on the arms of all places).When we are happy with the port at full draw we approach finish. We start sanding from size 120 to 320 for example. When sand out we Double check all surfaces for cracks, folds of compression, traces of the tools. If everything is in order (in this case it is) we start put on melted pork fat that is absorbed into the wood and makes it waterproof. She also gives a nice brownish tint. After the layer of fat, layer of wax is next that spreads over the entire surface( we are using hair drier ) until the entire bow is covered with a layer of wax that it also protects against moisture. I think that the process is not so important, it is easy to explain and therefore is not pictured. As the new owner wanted the app back to port we added it.Bow is than covered with a layer of clear coat finish...All these layers will protect bow from insects, moisture and it will last longer, clear coat isn't traditional finishing touch but it helps bow to last longer and prevents over dry'ing
The result: a bow made out of black locust is finished...
resource: old hill stormbow. Serbia