Sunday, 31 March 2013

Big Bow Gets a Workout

We went up the club with the big bow and got it throwing 32" arrows.
We played with different weights and looses, slightly up hill and into a head wind. At one point it seemed to lose a little distance, but the string had settled a tad and the brace height dropped about 1/2".
I shot my big old Yew bow which did pretty well, we were both getting just beyond the 180 yards, but expected more from the big bow. I had a go with one of the 11/32" shafts I'd made up with the 150gn point. We walked up the the flag and seemed to be an arrow short, until we spotted the one I'd shot about 30 yards beyond the others. John shot some different arrows and started to get a cleaner arrow flight and was making the same distance. There seemed to be a lot of variables in play and we had a good session.
The bow was declared shot in as it had even had a few arrows over 32" through it (and a car door!)
Examining the bow afterwards showed it had taken a whisker of string follow. The tips were bent maybe a 1/4" towards the belly (E.G with the tips against a straight edge there was about 1/4" between straight edge and grip). It will be interesting to know if that recovers after a few hours rest.
Here's a vid and a still. The video is cut down for a speedier download, the audio is probably annoying as it's cropped, but I'm saying 'At your leisure' at the beginning.

Update:-
I've messed about looking at the tiller by drawing ellipses, the pic with two ellipses allows for the stiff grip section, you can see the two ellipses aren't the same ovality which shows the different curve on the two limbs. The the single ellipse looks pretty good. We notice after the shoot that the scuff marks on the bow were a bit above the arrow pass (I hadn't tied a nocking point on the string).  Also of note, the linen thread binding the rather long fletchings (which were across the bow at brace) had been acting like a cheese grater and ripped out a couple of grooves in the bow!
I filed out the grooves, adjusting the curve of the side of the bow to ease the path of the arrow. A little sanding and a wipe of beeswax polish restored the look of it, maybe it will need an arrow plate adding. I tied a nocking point to give a consistent arrow location. I've heard people say that arrow plates aren't necessary, and I must admit I thought so myself, but then I don't shoot linen bound arrows!

video

Saturday, 30 March 2013

Hickory Challenge Result!

One of the reasons for doing this is to test the received wisdom.
Can a bow with 3" set be restored?
Can you tiller a hickory bow the day after heat treatment without allowing it to re-acclimatise / re-hydrate?

I rasped the tips much slimmer and put on horn overlays onto the back with a string groove filed in. You'll see that the tip is greatly reduced, but the original string grooves on the side of the bow are still visible, thus I've removed all that weight with no loss of strength.
With the old string the brace height is only about 3" now due to the slimmer tips allowing the string loops more slack.

Before putting it on the tiller I'd rasped some off the belly over the outer 1/3 of each limb. This was because I'd noticed that all the set on the bow was on the inner 2/3 of the limbs, so I assumed the outer thirds weren't working enough.
I put it on the tiller and winched it back to 50# I could see the top limb was a bit stiff, the lower limb wasn't too bad. It only came back to about 20". Excellent, that meant I had some poundage to play with and could remove some along the belly of both limbs getting a better tiller and a squarer cross section rather than the very rounded belly.
The 'classic D' section or 'high arched belly' of a longbow is a bit of an exaggeration, the Victorian bows were like that but the bows from the Mary Rose were more square or round with a slight flattening on the back.
Mind, actually looking closely at the capital letter 'D' it's not too bad an approximation if you round the back a bit.

I also took the corners off the back and rounded it a whisker.
This was done in degrees of course and slowly got me back to about 50# at 26" on the low brace.
Ah, yes, the string! A horrid thing of Dacron and much too thick with far too much serving weighing it down, not to mention a nasty heavy brass nocking point.
In the interests of a fair comparison I could make a Dacron string I s'pose, but I've got better things to do than make bad strings, so I found an Angel Majesty string that was about right and twisted it up an extra 20 turns to get it to fit, with a slightly lower brace height which gives a longer power stroke.
The tiller looks pretty good now, I think the upper (right) limb could probably flex a whisker more, but it's not worth messing about with.
I'll sand it down and give it a second coat of varnish (quick drying water based (acrylic?) ). I normally use it on my arrows as a wiped on finish, it's not very nice for a bow.

Results:-
5.7" Brace
~52# @28" (you can see in the full draw shot, it's a whisker over 28")
1" Set

Speed fps
162.0
164.3
167.9

That's an average of  164.7 fps (previous average was 141.4)
Pretty conclusive improvement. A rule of thumb is 100fps added to the draw weight gives an approximate speed, so you can see, it was below par before I tweaked it and now it's above par.
One has to be cautious, because after a few sessions of shooting it could well deteriorate, but I feel the bow is more evenly stressed now, and would hope it stays above the old speed.

Big Bow Update:- It will have had another two coats of Danish Oil by tonight making a total of 4, ready for a good wipe of beeswax polish in the morning ready for some shooting.




Friday, 29 March 2013

Big Bow Detail and a Hickory Challenge

The big bow got a bit of a work out this morning, I reckon I got it back to about 31" with some 11/32" arrows with 150gn points which I made up the night before. It's going to be left simple, no grip or arrow plate, instead a bowyer's mark, incised and the blackened with a soldering iron. It's a play on my initials (DH).
It will get a handed over on Sunday and a good work out with some clout shooting. I'll post some more pics then.



I tidied up my garage and came across a tatty Hickory bow. Mick the blacksmith gave it to me to play with as an experiment. He'd bought it V cheap as a first bow, just to get into shooting longbow. A guy at the club buys 'em in from the USA. They are cheap and cheerful, fine for getting started but not great quality.
This one had a bit of a grain run off on the edge of the back, which was begining to lift off as a splinter. I'd recommended gluing it and binding with linen thread.
My challenge is to take this rather sad bow and see if I can speed it up. I'll post it's stat's now so that I can't cheat later when I've worked on it!
I've clamped it up and heat treated one limb to remove the set, put in a whisker of reflex and harden the belly. Theoretically, once a bow has taken set the cells of the belly have deformed (crushed ) and you can't get 'em back to their original strength.
Hopefully, tempering the belly may gain some extra draw weight so I can then remove a little off the belly getting rid of some of the compressed cells and effectively letting some fresh wood which was nearer the centre of the bow do some work. I'm aiming to get the tips working a bit more too. I'm expecting to perhaps lose a few pounds in draw weight but gain some speed. I can loses some mass off the ugly tips too.
It's rather a tough challenge to set myself, but it will be a learning exercise. I've not used Hickory before (except as the backing of a hickory/Lemonwood stave I was given). I've  read plenty about it on Primitive Archer and it's supposed to respond well to heat treatment. It is supposed to not like high humidity, so I'll keep it warm and dry and varnish it.
I don't know when I'll get it finished as it's just a bit of fun, but I'll be sure to post the progress and results.

Hickory Longbow. Starting statistics.
69 1/2" nock to nock
6" brace height
Draw weight 52# at 28"
3" set, (e.g with tips touching a straight edge, the belly is 3" away from the straight edge)
Arrow speed (fps) 3 measurements with my 'standard' arrow (5/16, 28" 100gn point)
139.6
142.8
141.8

Wednesday, 27 March 2013

Tillering Symmetry

A while back, last year I reversed a bow on the tiller because it looked better.
I've been angsting (ok I may have made that word up) about my latest bow since the last post, I adopted my policy of 'when in doubt, step away from the bow' This is much easier once you are past 60 and the impetuousness of youth has waned a bit.

I had already reversed this current bow at about half way through the tillering as one limb seemed stronger.
Now the horn nocks are on and it's back to 28" I thought it was looking a tad weak on the left tip. So I tried reversing it back to the original way round.
Originally the slightly thicker, wider limb (we are talking maybe 0.5-1mm here) was to be the bottom one, this is in line with the measurements found on the Mary Rose bows and with current tillering practice. Even modern target bows are set up with the lower limb adjusted slightly stiff, by angling it away from the archer a tad more than the upper... they still call this adjustment of the limb in it's socket, (done by tightening or slackening a bolt) 'tillering', which amuses me rather.


To do this experiment, I marked the true centre of the bow and that's where it's supported on the tiller. I put masking tape at the true centre of the string and hooked the winch just above the tape (E.G about 1" towards the top of the bow so it's in line with the arrow pass which is 1" above centre)
I took a pic at brace then 27" draw (I didn't want to leave it at 28" on a freezing day while I messed about with the camera)
I then flipped the bow left to right and did exactly the same.
Now, to me it looks much better one way round.
I'm not going to say which, I'll be interested to see if you agree with me, comments please!
Here are the 2 pics at 27" draw (uncropped). You can see, in both pics the left tip is about 1 brick higher than the right*, so there isn't much difference, it's just the shape of the curve that's of interest.

The upshot of all this is, I have now decide which way the bow will sit, and I shall proceed with making a decent string and coaxing it back towards 32".

If you zoom in you'll see the bow is at about 63# at 27", this looks a bit low, but it's at a lowish brace height with a stretchy Dacron string. I'm still hoping for at least 65# at 28" after it fully tillered to 32"




*This is normal and is due in part to the way the bow is drawn from above centre. The braced pic below which shows how early in the draw when there is little tension on the bow it looks skewed (left tip is about 2 bricks higher than the right).
Some people make the mistake of having a bow dead centre on the tiller and pulling the string back from dead centre, this can make a huge differnece on a shorter bow, and when it's finally drawn by hand with an arrow on the string the tiller can look way off. It can be argued that maybe some of this is cosmetic, but it can cause the lower limb to be under undue strain and take a set.
In most bows the hand pressure is probably just below centre and the sting pulled from about an inch above centre.






Monday, 25 March 2013

70# @ V nearly 28"

I've teased it back and had a couple of test shots at 28" draw with my heavier arrows using my tillering string.
It feels good. Next step is to make a proper string.
It would have been easy to screw up while tillering the last couple of inches.
The tips weren't working much and I just went over the belly lightly with a rasp and tapered the tips into the nocks a bit more.
I got it on the tiller and took the rope off the winch so I could lean back on the opposite wall (where the camera is mounted) and pull back and forth on the rope. As it was approaching the 70# I could see the left limb was now working much too hard at the tip and was a whisker soft compared with the right.
I marked W on the weak section and scribbled a line where i needed to take off a little wood mid limb.
A little light rasping near the middle of the left limb and some all along the right improved the balance and got me back to almost 28 inches at 70#.
If you make the video full screen and stop it at full draw you may see what I mean. On the other hand you may think it's fine, such are the subtleties of tillering.

I think the left limb has a tighter curve than the right especially in the outer half. I'll get the whole limb working a little better before risking taking it beyond 28". Having the stiff spliced section in the centre slightly confuses the issue from my usual arc of a circle tiller shape.
Further explanation of the shape:-
It looks slightly 'square' to me e.g flat in the centre and then a corner and the tips coming down too hard, sort of whip tillered. Mind there's half an inch to go really, so just easing off the right limb a bit and some off the inner third of each should do the job.

video
It's rather nerve racking as it's a very good bow at 28" with no set, so I'm going to be V cautious about taking it further. I'll shoot it in at 28" and gradually work it back keeping an eye on the tiller of course.

It's easy top get nearly there and think all the hard work is done.
A young guy was over at the weekend to split an Ash log, we sawed it in the end as it was fairly small and it seemed better to end up with two good staves rather than risk twist or wander off and end up with none.
He was telling me how he had a Hazel bow blow up at about 25", but he felt he'd probably rushed it. That's just the point I'm making, take your eye off it for a moment and it runs away from you.
He has a very long draw (about 31") and asked for suggestions... well all I could offer is to start with a much longer stave or, with shorter primitive style bows shoot native style by drawing up in front of your face. The Ash log was 9' long, so he has plenty to play with!

Tillering is tricky as you need one eye on the draw weight, one on the draw length and one on the curve of the bow limbs. Take your eye off any one of them at your peril!

Sunday, 24 March 2013

Tillering Progress

I've been teasing the bow back, running calipers along the limbs checking for a gradually increasing gap with no thick spots. The tips have been narrowed an bit and the corners rounded off so its near the final profile. This work has slowly eased the draw length back to about 26" and I can now string it (at a low brace of about 5") without the stringer.
I've noticed the slightly thicker lower limb seems to flex more and the bow looks better reversed on the tiller, so that's what I've done.
The heartwood belly is made of two billets, but they are not from the same log and thus not perfectly matched. They are both from the same batch of Yew cut in the Cascade mountains.
I've gone over the bow with a scraper too and its looking very handsome now. I think it's time to do the horn nocks before taking it back any further, doing the nocks will narrow the tips a bit and get them flexing more, that may well get me to the 28" draw mark.
In the video, you'll see I'm flexing the bow back dynamically rather than winching it back slowly, I feel it's kinder to the bow.
Nearly all the cambium has come off now leaving a lovely clean back except for a bit of staining where another branch had been chaffing against the bark, this will probably clean off in the final stages of finishing.
video
The tiller looks pretty good. Stopping the video at full draw, displayed full screen and holding a CD up in front of the screen I can see the left limb is a fairly circular shape, the right limb is very slightly weak just right of half way along. The centre section is stiff, but that's intentional to give strength at the splice in the heartwood.
This stage of tillering in my opinion needs to be done very slowly with lots of time for looking and thinking and minor adjustments. It's easy to get fixated on one area and miss something else like the string alignment.
Conversely it's easy to overthink it and start chasing shadows, I'll be looking at the video every now and again, maybe winch the bow back to about 60# and have a good look at it and run my fingers over it.
One problem in my garage is, I can't get far enough away to get a good look at it, hence the use of video.

Saturday, 23 March 2013

Big Bow Braced

The big Yew bow is now at a low brace and pulling to 70# at about 21".
in the video you can see some cambium pop off the left limb as it draws back, if you turn the sound up, you can hear the sharp 'tic'.
There's a hint of sideways bend but I just heavedthe string across at the nocks a bit. I'll true up the centre line before taking it back any more.
It's looking good.
video
Update:-
Saturday evening 70# at 23" from a 4" brace height

Thursday, 21 March 2013

Starting to Bend the Big Bow

I've glued on some chunks of sapwood and cut in temporary nocks which allow me to get the bow onto the tiller. I'm aiming for 70# at 28" and a full 32" draw at whatever draw weight it comes out at.

I'd left the cambium layer (the pinkish stuff under the bark which covers the sapwood). With my poor colour vision, I probably didn't realise how thick it was.
I expected some thin fibrous stuff to pop off with a 'tic', and indeed, one section did.

What I didn't expect was a rifle shot 'crack' as a whole layer came off and scared the crap out of me. Initially I wasn't sure if it was the sapwood splitting, but in decent daylight I could see the colour difference and the pristine creamy yellow of the beautiful freshly exposed sapwood.
Whew, it's a labour saving way of getting a perfect sapwood back, but not for the faint hearted.
Interesting that the fracture started at a line of tiny pin knots.




Monday, 18 March 2013

Glued Up Stave & Bonkers Bow

The glued up stave looks pretty good with a barely visible glue line, and I think there's enough wood there for a decent draw weight.
It barely flexes at the mo'.

I've taken off the outer bark, the cambium remains and I can do my marking up on that. The cambium is horrid bitter smelling dusty fibrous stuff. I don't often bother with a face mask, but I do when I'm scaping that off.
I'm taking it carefully as I want to preserve a flawless sapwood back
I've run a string line down it and trued it up width wise, it's nice and straight, I'll do a bit of work on the thickness later today.

I've also finished of the Bonkers Bow and got a full draw pic.



The tiller on the Bonkers is surprisingly good, it was only really made for the hell of it.
It was virtually finished last week when I noticed a small dry knot on the belly. On the back there was a tiny hole in the sapwood, I poked down it with the tip of a needle file and the knot just fell out of the belly! I filled that and then spotted a dark patch on the edge of the bow where there was a knot just under the surface. The sapwood was rather thin above it and there was a sign of a tiny crack. I rasped that off and added a patch to the edge.

So it's got a back patch a belly patch an edge patch and half a dozen plugged knots. It's also had a fair sized lateral bend put in at the grip... but other than that it was easy peasy!


Friday, 15 March 2013

Glue Up

I've glued up the Oregon Yew Heartwood and English Yew sapwood. It's quite a tough job binding it up with two layers of rubber strapping. Once strapped up, I clamped the middle to a length of dexion steel angle and put a wooden block under each tips forcing it into a slight reflex. Ideally I'd probably clamp it to a former, but that would be tricky with the rubber binding, and I'd have to make the long former.
Because the stave has already been shaped to a reasonably even taper it should take on a smooth curve just by lifting the tips, in an equal and opposite way to how it will form a nice curve when drawn in use.
I expect some of this reflex will spring out when it's unstrapped and some will pull out during tillering. I'm hoping to end up with a nice straight back to the bow when it's finished.
The glue is Resintite which is in powder form, is mixed with water into a fairly thick liquid, I take care to weigh the powder and liquid as per the manufacturers instructions. I use Highland spring water to mix it with as it's purer than our tap water I don't know if it's important, but I happen to have some, so why risk our hard Essex tap water?
The manufacturer says only apply the glue to one surface, but I ignore that as I want to be sure that both surfaces have been thoroughly wetted and that there is enough glue to squeeze a little out as it's bound up (see pic, you can also see the bark is still on.)
The surfaces were prepared by rasping along their length with the rasp held sideways to score the surface along the length rather than actually rasping away any wood.



I've also been cleaning up the bonkers bow, plugging another knot and adding a small patch to one edge where there was a dark stain which turned out to be a buried knot.
I'll blog up the finished bow with all it's patches and fixes when I've finished it. I'll probably put it on my website as an example of the sort of abuse Yew can survive.

Monday, 11 March 2013

Steaming a Sapwood Backing Strip

I've been doing some work on an experimental 'Transatlantic' bow. Oregon Yew heartwood spliced belly and a continuous strip of English Yew sapwood for the back. There's no great reason for the nationality of the timbers other than what I have available.
The heartwood stave has a slight lateral bend of about 1/2" which I've steam corrected. I wouldn't normally worry about a 1/2" bend, I'd just lay the bow out straight, but I have very little wood to play with (width wise) so I'm trying to get it as straight as I can to avoid ending up with a bow as wide as a pencil.
The sapwood backing strip had a huge twist at one end which I've also steamed out.
I did the heartwood Saturday evening and got the sapwood done Sunday morning before we all went out for a Mother's day jaunt.

The twist came out quick and easy as the strip was so thin (about 1/4"). I've left the bark on, this will stay on as long as possible as some protection for the sapwood.

In the pic you can see the heartwood spliced billets in the vice and the sapwood (bark still on) being steamed.
Note the insulation to keep the heat in and the way the bench has been propped up at the far end to let the water run out into that old washing up bowl. As the steam condenses into water it delivers heat to the bow, and the resulting water can be quite cold.
Note:- There are other posts on the blog which explain the set up in more detail...
http://cr4.globalspec.com/blogentry/20574

Any heat bending is about heat and time, if it's not hot enough for long enough it won't do the job. There are pros and cons to steam or dry heat, and I use both. Steam gives a good even heat over a decent area, but being less hot needs carefull setting up and can be spoiled if you have to waste time getting the wood out of the heat and clamped up. That's why I try to heat and clamp in one operation if possible. It's always worth the time and effort getting it all set up right, rather than ending up doing it twice.

I was hoping to get it prepared and glued up today, but there are flurries of fine snow and it's damn cold in the garage.
Meanwhile I've been applying the finish to the gold arrow plate longbow and signing it ready for collection.
I was chatting to Mick the blacksmith and I'm putting a grip on the bonkers bow for him as a thank you and swap for some forge/instruction time. He was rather taken by it's mad look yet crisp shooting performance.
It's nice to know it will get a good home and some shooting rather than standing glumly in the corner as a novelty.

Saturday, 9 March 2013

Gold!

Had a brilliant day yesterday smelting the gold for the arrow pass. Mick took us to his workshop, it was like an Aladdin's cave, chock full of wonderful machinery that made me drool.

Being rather woodwork based, I've not often got to see the big stuff. This was great, there was all sorts, milling machine, lathe, huge old weird radial arm drill that I had to ask wha's that??? several forges and a power hammer, all the usual smaller stuff. Power saw, grinders, belt sanders welders, sandblasting booth. The sort of stuff that no home should be without.

It was a real blacksmiths/engineering shop with that lovely smell redolent of old railways and traction engines and loads of stock material of assorted sizes and offcuts of useful stuff under the bench. Mick gave us a thumbnail sketch of some of the stuff he does and picked up what looked like a plain bar with something like '240 layers' chalked on it, a quick clean and etch revealed the multiple layers and pattern of pattern forged steel. I could see the necessity for chalked on notes.

Mick hadn't smelted gold before so we'd talked it over and trawled the web and Youtube to find how to treat my nice new graphite crucible.
It all went smooth as silk, Mick tack welded my mould onto a suitable base plate, the crucible was heated red hot and some borax sprinkled in and melted. The gold was cut up an put in and back into the forge, it melted pretty quick and was poured into the mould which was heated dull red. The last small pic shows the resulting pellet of gold being annealed after some hammering.

The gold formed a bit of a mushroom head above the surface of the mould and we worried it hadn't filled it.
Nope, there was more gold than we'd realised!
I'd made the mold on the small size, expecting only a little gold so we took the opportunity to hammer it out to a larger size, knocking down to about 3mm thick with the power hammer. The power hammer was a thing to behold, I'd not seen one in the flesh before so Mick obliged by heating up some steel bar and forging it between the curved section of the die (jaws/anvils) of the power hammer to stretch it. (The jaws also had a flat section and a curved section, the flat section was used for flattening the gold).
I'd forgotten to take my camera but Shaun took some pics on his phone which give an idea of what was done.
Once we'd done it was back to may place for a well earned egg and bacon buttie and a play with the bows and my stuff.
In the evening I filed down the gold to a shield shape for the arrow plate, taking care to collect all the gold filings.



Saturday Afternoon:-
I've done the inlay and the leather grip just got to give it umpteen coats of Danish oil and we're done.

I've just weighed the dust, there's about 4g which means there's about 6 in the arrow plate. Dunno what carrat gold it is, but it's gotta be over sixty quids worth!

Thursday, 7 March 2013

Assorted Stuff...

I've been thinkering about with all sorts of stuff, making up a dozen arrows in dribs and drabs. The fletching jig is on the hearth and every now and again I'll stick on another fletching.
I've spliced up my last decent Oregon Yew billets (with the bug damaged sapwood sawn off). The English Yew sapwood for the backing has been cleaned up, but I have two bits, one is wafer thin and the other has a twist. The sapwood is continuous full length strips which should help ensure the splice holds solidly.
I'll go for the thicker twisted bit as I'm aiming for about 70# at 28" but tillered out to a full 32" which should be about 85#.
I'll need to steam the twist out before gluing it up. The Oregon Yew hasn't got a lot of spare timber to play with so I may have to steam a 1/2" of lateral correction into it. When I finally get round to the glue up I'll put an inch or two of reflex into it.

Meanwhile the 55# longbow which I've been shooting in is ready for it's arrow plate... the game plan is to cast some old scrap gold into an arrow plate and then inlay it into the bow and add then finally add the leather grip.
One of the guys at the club Mick Maxen is an ace blacksmith and does all sorts of pattern welded steel, if you google that name you'll see some of his stuff.
He's going to let us play with his forge tomorrow to smelt the gold.
I've bought a 30mm x 30mm graphite crucible to melt it in and I've made a mold from steel plate which can be tack welded onto a backing plate to pour the gold into.

I marked out the plate, drilled out the bulk of material and then filed it to shape, it didn't take too long as it's only mild steel plate. I've filed the hole in the plate with a slight draft angle so the gold will hopefully come out... a 4lb hammer will doubtless persuade it if it's being stubborn.

While I've been in and out of the workshop I noticed the big Elder log I cut the other day had started to split (probably drying out too quickly where I'd taken off some of the moss covered bark. I could see it was twisting so I thought I'd see how bad it was. I used the axe and wedges to split it, but it was like a corkscrew... such is life. Some you win, some you loose, and bearing in mind what I paid for the wood , it was worth every penny!
The other smaller piece looked ok, so I used the bandsaw to cut that down the middle, that should help release some of the internal stress and prevent splitting. I think there's a decent bow there once it's seasoned.


Sunday, 3 March 2013

Yew Longbow After Heat Tempering

The bow has had a good rest now so I put the string on at low brace and started pulling it back on the tiller. I was pulling on the rope rather than winching it as it gives a better feel.
Pulling it back and forth working up towards 28" my heart jumped into my mouth at one point as there was this horrible sharp noise, but it was just the string snagging slightly as it moved in the nock.
This raises a point as I've recently seen a couple of bows with narrow grooves on the side of the nock for the string to sit in at brace. This is nonsense as the string moves up and round as the bow is drawn and won't want to stay in the groove. Well I didn't have a deep groove, but the loops on my tillering string are big to go over roughed out staves, and one was snagging probably on the edge of the horn nock.
Anyhow this horrid snapping noise always happened at 21" so I ignored it, and slowly got her back dynamically to 28" where she was about 58#. (target weight is 55#)
Theoretically you should never draw your bow beyond it's target weight or length, but a few pounds is neither here nor there. Those few pounds give me room to ease of the slightly squarish corners of the belly which were looking a bit more American longbow than English longbow. There was a hint of a tendency for the bow to be favouring one side, so I eased off the corner more on the opposite edge to encourage it to settle in line.



I've been finishing the horn nocks too.
Pics show how the deflex has all gone, the pith showing on the belly and the nocks which are so translucent you can see the grain of the wood through them.

Saturday, 2 March 2013

Bonkers Yew Character Bow

The bonkers bow seems to have survived to full draw. The shape of the stave has lent itself to rather narrow stiff tips reminiscent of the levers on a Mollegabet style bow. There is some ugly deflex near the tips, but at the lower one I can't risk heat straightening it because that's where the glued back patch is.
I'll probably leave the upper tip alone an see how it shoots. The very narrow grip gives a clean arrow fight.

In response to the question on patching, here's 2 pics of the finished belly patch which was a dead flat join (shows in the 2nd patch pic) just to build up a thin point in the stave. Well I call it a stave, but it was just an off-cut from the edge of a half log that looked only fit for firewood.
The patch also helped to brace across a rather large knot. Top right of the pic you can also see a plugged knot.

I've done the nocks very simply, sometimes you'll hear "don't cut into the back of the bow" this is because it will weaken it. Like all these things, it's a good rule of thumb, but done sensibly on a narrow deep tip it's fine, you can see those tips aren't going to be flexing at all.

The video shows a surprisingly good tiller... well it surprised me! It's pulling a bit over 45# at 28" on a lowish brace height, as I used a string I had lying about. The arrow pass is well above the centre line and the grip about centred on the true centre of the bow.

The longbow I've been working on has it's horn nocks done and will get tested this afternoon, or tomorrow morning, having had a while for the heat treated belly to settle down.
Update:- Ive tried the longbow at low brace up to 50# at about 26" so I'm fairly confident it's gained a good few pounds. I won't take it to full draw until I've gone over it carefully smoothing and inspecting and finishing a bit more, that'll be tomorrow when it will also have had another day to re-acclimatise.
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