Heat treating a bow Vol.2- the heat is on……………

Making wooden bows you´ll sooner or later come across a so-called propeller- twist. Basically this is the growth of  wood around a bigger knot. No doubt, it is a good idea to localize a bigger knot within a bow- stave at the bow´s handle, there is no bending, no tension, no compression. But what you´ll get is a propeller twist. The wood at one side of the knot is growing to the right, at the other side the wood is growing to the left. More or less the bow will look like this:

the terribly twisted locust stave

twisted locust- the limb below is reflexed, the upper limb is deflexed

No way for to tiller this bow! The limb below is reflexed and turns to the right, the upper limb is deflexed and turns to the left. The stave has turned out to be an extra hard and springy kind of Black locust. The bow is 63″ in length, done according to the American flatbow design, as mentioned above a big knot in the handle has caused the twist. Cause of  the growth, it turned out to be impossible to make a test- bracing, anyway the string would lie more than 1″ beside the handle.

The bow has been made by a participant of one of my bow- classes last spring, a very straight and strong looking guy. His high voice made me somehow suspicious: he really turned out to be completely untalented in crafting a selfbow. I´ve to support him at every step of the making of the bow, while the other 9 participants have to wait. He has chosen this stave by himself, ignoring my advices to choose one of the straight and clear staves. Somehow he felt challenged by this stave, but he would have failed with any stave. End of story: I´ve to finish his work……….bow- classes are “en vogue”, but sometimes its really hard to get by with the disabilities of some participants.

Heat- treating is the medicine for a bow like this:

heat- treating the easy way- a straight stable log, clamps, a heatgun and a clock

That´s the usual setting for an easy heat- treating. The bow is clamped down on a straight stable wooden log, belly side up, the reflex is provoqued by laying a piece of wood underneath the handle. I don´t go for too much reflex by heat- treating. For a higher amount of reflex advice steam- bending. Take care to fix the bow in a straight line. The limbs have to be marked with a pencil every 2″, the clock is used for to assure, that every marked section is heated the same time. For to adjust this bow, a heating of every section for 2 minutes is enough. Make your trials and errors, less heat- treating is adviced when you ´re a heat- treating beginner. Release the bow, when it has chilled. If the result is not satisfying, do another run. It is possible to heat- treat a bow till the wood begins to smell or gets a darker colour.

.....this was a twisted bow..............

Note “the toasty colour”, the marks and how straight the bow is now.

succesfully straightened the bow, braced

Finally I got it! A working black locust bow drawing 47lbs at 26″:

still a little tillerwork to do- the bow looks fine- still a bit twisted

It is not possible to remove the basic grown shape of a stave with heat completely, but isn´t the bow charming? Heat- treating is a number one tool for to make a bow working with a correct tiller, that´s one purpose of it.

For to adjust a bow a primitive setting is enough, but there are much more refined ways toheat- treat a bow.

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Heat treating a bow Vol.1- basics- gimme some heat

Heat treating or tempering a wooden bow has turned out to be the magic formula in selfbowery since Marc St.Louis, the well reputated Canadian traditional bowyer has published his experiences with it in vol. 4 of  “The Traditional Bowyers Bible”.

Thank you Marc for publishing this precious tool.

I had been always suspicious to treat a bow in a somehow extreme way. The heat of a heatgun or of its forerunner the bowl filled with burning pieces of charcoal used by the Osmanian hornbowyers seems to be an extreme way. But Marc St.Louis was always wondering about some tribes of Native Americans having preferred wood of trees which have been strucked by lightning. He got more and more curious about it. Look out for Traditional Bowyers Bible Vol. 4 .

I did never use heat- treating for wooden or sinew- backed bows. Usually I´ve steam- bent a reflex or recurves or a more or less twisted stave. I used heat- treating for to shape horn or to adjust a hornbow, or to enforce a bamboo- slat of a boo- backed bow.

Marc´s report made very clear, that you can´t destroy your bow, if you heat- treat nothing but the belly of it. The belly is the compression side of a bow. Wood is stronger in tension than in compression.

Heat makes wood compressing and so it becomes hard and dense. Remember our ancestors getting reliable arrows by heat- treating the arrow- tips. Marc St.Louis noticed that heat- treated pieces of wood have lost weight and  a flat belly of a bow will get a concave shape after a heat- treating. So it´s clear that heat- treating will have more impact on more porous and lighter woods than on more dense and heavier woods.

Heat- treating a selfbow is one of my favourite tools for adjusting and enforcing a wooden bow, I don´t want to have missed it.

My first experience in heat- treating a bow was very impressive. I´ve done a selfbow of black locust in the American flatbow- design, 38lbs at 28″. It was my intention to make a bow not to strong, for to get some data what a heat- treating is able to do. It took me some nerves and 2 heat- treating runs of about 20 minutes. Drawing the bow the next day turned out to be a real burner: 52lbs at 28″, I´ve heat- treated a small reflex in the formerly straght grown bow- stave too.

I use heat- treating for to adjust bows, for to put smaller amounts of reflex into a bow, for to make  bows stronger. Everytime when you heat- treat a bow, its compression strength is rising.

I use steam- bending for to get higher amounts of reflex or sharp recurves and for to get more drawweight too.

I´ll go on with a lot of concrete examples.

Great errors- the great mulberry swindle

There are fatal errors in our life, there are average errors too. A great error has just happened to me, a great error is an error making you marveling finally. To call it a swindle is a bit excessive, but makes a startling title.

Mindful readers of the bowXplosions may remember:  “Midsummer on hornbeam- mountain” and f.e. the following pic:

rock and osier

Here we are, rock and osier; sorry, osier is wrong! This tree is very common on the Belchen mountain, for whatever reason I thought it to be a kind of osier, cause there are a lot of osiers are around here. My neighbour is always calling osier rubbish, worth of nothing, even bad fire- wood, something to cut when it gets in your way ( a real Rambo- farmer).

Collecting some hazel- bowstaves nearby my farm, the other neighbour was passing by. We were talking about the similiarity of hazel and alder, both belong to the corylus- family, they are really easy to mix. But the wood of the hazel is white, whereas alder is red. He pointed at the slope vis-a-vis, asking me if those mulberries there would be a good choice for making bows?

mountain maples and birches in front of so-called mulberries

Mulberry!!?? Mulberry is one of the best reputated bow- woods. Mulberry is highly estimated by bowyers in Asia, even the famous Korean hornbows are made with cores of mulberry. I´ve heard about some mulberries growing in botanical gardens in Germany or Switzerland, I guess there are more mulberries in some  southern parts of Europe. “You are really sure that´s mulberry?” “Yes for sure, we´ve lots of mulberries here, even on the Belchen Mountain, my father knows them, my grandfather too. Ask the ranger!”

At home I googled for “mulberry on Belchen mountain”: I met hiking the Belchen mountain- reports telling the same story. How could I be so blind to miss this treasure, mulberries all around. I dreamt of making a mulberry- bow the next day.

Heading for to cut a mulberry stave with my big saw and an axe next morning, I passed the neighbour again: “Oh, you just try to get some mulberries, good luck, I´ve just talked with the ranger about it, he would appreciate you to cut that one beside the barrier of the forest track. He told me that the elders have called the mulberries “Mehlbeere” too.” Wait a second: “Maulbeere”, “Mehlbeere” is this the same? In German the terms “Maul” and “Mehl” are sounding similiar, above all spoken in rural dialect. I returned at once, googling for it: it took me some minutes( ages for google), but I came across a linguist clearing up the backgrounds: “Maul” and “Mehl” have been mixed up, almost in every German dialect the “Mehlbeere” became a “Maulbeere”. “Maulbeere” means mulberry, the english term for “Mehlbeere” was not easy to find, the common term is whitebeam, a former term is haw, sorbus aria! The German term “Mehl” means flour and so I had to think about floury wood, no way for a bow. But haw means a relation to hawthorn, a premium bow- wood, rowan another well reputated bow- wood belongs to the sorbus- family as well as serviceberry, a solid bow- wood too. All sorbus- trees are rosaceous plants.

I´ve to admit I´ve never heard about whitebeam.

whitebeam- just in front of our farm

Usually whitebeams- trees have a big trunk with thick straight branches.

whitebeam- fruits, leaves

The German term “Mehl” means flour: the berries of the whitebeam had been collected, dried and pestled for to add it to the bread. The whitebeam- flour is flavoring the bread and is saving it a longer time. Great, I´m a passionted baker, but the berries are still green. In fall, when the berries will be red and orange, I´ll go for them.

We have 3 neighbours here, the 3rd one is not a farmer but a kind of crazy gardener and above all a hobby- geologist, knowing a lot of facts about plants and stones and rocks. He told me the whitebeam to be a kind of hangover of very ancient times. More and more I´ve to realize that we are living in a real paradise here.

Again I went out for to cut some whitebeam, the mulberry- swindle was over then. I found a big whitebeam with a very clean trunk, straight branches, cut down about 2 years ago, not to much indications of rottening, just left for me!  I don´t like to cut living trees and I whenever it is possible I´m going for dead wood. Woods like whitebeam are not worthwhile the needs of modern timber industry! In former times whitebeam- wood was highly estimated by cabinet- makers for its outstanding durability and beauty.

splitting whitebeam- bark, leaves

I debarked and splitted a thick dried branch, keep care of the short but hard and sharp barbs, a joy to work it, a very clean wood. Easy to shape with the drawknife guiding according to the fibres and the growthrings.

a first whitebeam- bow in the making

I choosed the very solid American flatbow- design: about 65″ in length, 2″ wide near the handle, tips are about 1/2″ in width, for to be become confident with the wood I worked the limb down to 3/8″ in thickness. The limbs could be bent a bit, I tillered the limbs step by step. The bow is not finished right now, I´m at about 25″/60lbs.

whitebeam- bow- braced

The bow is not ready, but it works, some tillerwork still to do, the limb at its left is bending to less.  I guess I´ve to do some heat- treating for to straighten the naturally grown whipped ends.

belly- side of the whitebeam- bow

Encyclopedias are telling me, that the whitebeams are growing all over the world, they even could stand heavy climate and bad environmental conditions. There a lots of whitebeam- bastards or hybrids, f.e. serviceberry and whitebeam mixed up. Whitebeam could be a big tree up to 80ft, or a small tree like on the Belchen mountain. It has been a favourite for making woodturning, handles for tools, even gears had been made of whitebeam.

As a bowwood I´ve to highly recommend it. Look out for it, there is an unknown treasure around.

And I´ll make up my mind for to see the things just before my eyes. Otherwise I´m a kind of robot, realizing nothing else but something I still have in mind. Like a programmed TV set. This planet is a miracle!

I´ll update the whitebeam- bow.

Midsummer on hornbeam- mountain

Every midsummer my wife, our daughter Maja and me used to climb up the Belchen, the highest mountain in the region. It is not to far, our farmhouse is just at the foot of the Belchen, it takes us about 3 hours to hike the top. The Belchen is told to has been a magic place, where Celtic Druids have done their rituals, above all it is assumed that it has been a kind of observatory of the Celts for to watch the movements of the planets. It is told that our Belchen here is one section of a big observatory of the Celts, being connected with the Ballon d´Alsace, the Petit Ballon, the Grand Ballon in France and the Jura Belchen in Switzerland. The name of the Celtic god of the sun is Belakus, so this region has been a place of sun-worship.

mountainside of the Belchen- forested grazing land- osier, hornbeam, pasture beech, mountain maple

It´s really the 21th of June in 2010, but it is cold today: 54F, a long cold winter, almost no spring, hard to believe. The steep rise makes us sweating, the trail is sometimes stony, sometimes a bit muddy, again no sunshine.

looking south from Belchen- clouds and the village of Neuenweg

Not to long ago during summertime the slopes of the Belchen has been a precious grazing land for the cattle of the farmers here. Cause of the rural exodus, this is history. The trees are coming back, at the foot of the Belchen you hike among coniferous woods, the slopes up hornbeam, pasture beech, moutain maple, osier and rowan is growing becoming more and more smaller,at the top of the Belchen you´ve passed the timber line.


bizarre pasture beeches and hornbeams

About halfway we were passing one of most strange forests I know, it´s like a magic forest, there have to be elves and dwarfs. The beeches and hornbeams growing here had been damaged by the cattle grazing here in the past. When the cattle has gone, the trees grew into bizarre shapes.

bizarre hornbeams and pasture beeches- my wife, my daughter

Passing this forest makes me always thinking about the appearance of Mother Earth, of how to come over with every kind of conditions. Every obstacle is a challenge for to try something new, for to create new designs…………..that´s evolution.

multifaceted trunk of a pasture beech
very, very old hornbeam

Due to this forest I call the Belchen hornbeam- mountain, even there are growing only a few but very impressive hornbeams. The so- called pasture beech is white beech damaged by the cattle, whereas hornbeam is a member of the birches.

Leaving the magic Belchen forest
rock and osier

Climbing up the Belchen every years midsummer made me thinking of what has grown within myself. Have my dreams come true? It is time to take care of the fruits, from now on days are becoming shorter. Hiking up the steep slope passing the beauty of the trees and rocks is a my way of  honouring all the trees I ´ve cutted for to make bows and arrows.

When we reached the valley again, summer has begun. Since 3 weeks it is really hot at the foot of hornbeam- mountain.

finally summer has begun!!

Selfmade clamps for laminated bow- constructions

About 10 years ago I did my first hornbows with usual bow- woods as a core: ash, elm, black locust, wild cherry………The glueing turned out to be a kind of not to much reliable The glueing procedure itself was  becoming more and more a thing of chaos and even some horror:  glue drying to fast, fingers full of glue, glue everywhere, all things glued up but not the horn to the core- wood…………….these flops made me to think the whole thing over, to reset and to update my mind about traditional glueing of laminated bow- construction. Remember 10 years ago the infos dealing with hornbows and other laminated bows were not as wide- spreaded as today. It took me another 4 years to become able to manage the procedure in a more secure way. When glueing bow- lams with natural glues it is a must to organize the whole procedure very carefully. Clean and degrease the parts to be glued with curd soap, coat them several times with a thin solution of glue: water- glue= 5 : 1. Take care that the workshop is well- tempered- 77F, as well as the glue- 150F, preheat the wood and the horn to about 75F. Place your clamps or rope ready for to go. When the glueing is done fix the lam to a straight and stable wooden lath for to make sure that the bow will stay aligned. Maybe you want a reflexed or recurved bow, so fix the bow to an according wooden form. This procedure is called glue- shaping.  The Japanese makers of the traditional Yumi- bows are using a rope and wedges made of bamboo for to glue- shape the multicurved yumis.

After having done my experiences in glueing bow- lams I ended up in using selfmade clamps for to match as exactly as possible the needs of a well working glueing.

selfmade clamps- bottom-, side-, top view

The clamps are made of mountain- maple slats cut to 3″ in length, about 1/2″ in thickness for the bottom piece and 1/3″ for the upper piece, width is about 1″. For to screw them down I use thread rods and fitting nuts, countersinked into the bottom piece of the clamp. It´s also a good idea to use winged screws, but for to develop heavier pressure I prefer to screw the clamps down with a ratchet wrench.

selfmade clamps in action- use a wrench of your choice or wing screws

It´s also possible to do these clamps by glueing small pieces of wood at their internal sides for to guide the lams not to slip out of place. But don´t do them to thick, otherwise you can´t produce the necessary pressure: I leave an open space of about 1″ – 11/2″ in width and about 1/3″ in thickness,  you can make clamps with more or less open space matching the different cross- sections of the lam.

another view of the clamps in action- note the glued on small pieces of wood working as a guide

Before using the selfmade clamps open them up, organize the glueing well, prepare all tools you need, take care for the right temperature of the workshop and the glue.  The advantage of these clamps is that you can develop pressure where it is needed, more or less. Don´t screw them down to heavy.  Just as far as the glue is flowing out of the glueline.

These clamps are highly effective, done by yourself you´ve to buy screws, nuts and thread rod. Choose them made of iron not made of aluminium, as I did it for the first time. Iron is much more stable.