Friday 30 September 2011

Finishing

The final finishing, minor tiller adjustments, sanding and narrowing the tips and shooting it in with 50 arrows or so has lost a few pounds draw weight so it's nearer 40# now. Some of that may be due to my shaping the handle which allows it to sit a bit lower on the tiller (I havn't bothered to adjust the rule). It seems to be shooting sweeter now and grouping really well, normally if I group the first 3 arrows I then loose it, but this bow just keeps banging them in the same spot. I'll shoot it at the club on Sunday and post a few more pics.

Wednesday 28 September 2011

Test Shot+Update

I've been shaping the nocks this evening, they will look a little odd as the tips of the bow are twisted over at about 45 degrees. I've glued on fairly big chunks of Waterboffalo horn as this will allow me to cut a groove lined up correctly to the plane of string and bow, the nocks will look slim from one side and fat from the other.
I found an old string which fits, although the bracing height is a bit low, I shot 3 arrows, just to test it, but I seemed strangely reluctant to pull it back to full draw.
Maybe I'm still a bit bow shy having broken that last bow (the Hornbeam) or maybe I'm just being sensibly cautious untill the nocks are fully shaped and I have a proper length string on it.
I've had it back to 28" 45# on the tiller using my tillering string adjusted to the right length.
A bit more work on it tomorrow cleaning it up and I'll shoot a few more arrows through it and start serious finishing. Pics in a day or so.
I shall give it a good try out at the club at the weekend.

Strange results!
I made a decent string, the bow didn't seem to shoot very fast, but I think I was holding back as it was slapping my wrist a bit. I put on my bracer and it was more comfortable and I could get a nice full draw. It felt much faster and grouped really well, but slightly low and left. So I took the Hazel bow and that seemed to shoot higher, hmm strange.
The difference can't be accounted for by speed as it was too much and the Hazel bow is probably slower.
Maybe the grip or arrow pass just makes me shoot low. Anyhow I got the chrono' out to settle the matter of how fast it shoots.
I got an average of 167.47 fps (having discarded the fastest and slowest readings) thats 114.18mph which is a good bit faster than the Hazel bow which doesn't quite make 100mph. That's very respectable for a 45 pound bow, and virtually as fast as my 50# longbow.
They say a rough guide is to add 100 to the draw weight to give a figure in fps.
For the record, the fastest reading was 169.1 fps

Monday 26 September 2011

Final Stages

I've been taking out the rasp marks, cleaning up the bow and adjusting the tiller a tad.
It' back to 45 pounds at 27" now, so that's about it. I've been narrowing the tips some more and checking the string alignment. The bow looks good at full draw from front and sides, the twist is still pretty obvious in the limbs, but they seem to track back nicely.
Here's a couple of pics of the back, showing how I've worked the growth rings, one shot is still while the back is rough as it shows better. The shots are dark to avoid bleaching out the detail. In the first pic you can see how I've allowed the rings to ripple around the row of knots along the right edge, leaving a few extra rings for strength.
The second pic shows the long continuous line of one growth ring down the centre.
There's a lot of patient work in taking the back down one ring at a time, but once it's down to this state, it's pretty easy to follow a ring and take it along the bow or out wider to the edges. An big old bluntish 12" half round file worked lightly across the surface sort of crumbles off the pale wood without digging into the more yellow wood of the next ring, or a scraper run along the length of the limb smoothes out the rings and blends them smoothly.
Once it's had a bit more mork, some fine rubbing down and a few coats of Danish oil it will start to look really good, a year's ageing will help too!
The belly pic shows the wood is looking quite handsome and there are no real tool marks left, any more tiller adjustments will probably be on the with of the bow or gentle rounding of the edges of back or belly.

Club 3D Shoot

I decided on the Hazel 40# bow for the shoot, but wanted to freshen it up a bit and add a whisker of speed. A new string of Angel Majesty should do the trick.
I almost contrived to screw it up, the old string had been in the bottom of my bow bag and had somehow got a knot in it. I was using that to get the length for the new string. Fortunately I spotted the knot it in time else I'd have spent an hour making a string 1/2" too short, which could have broken such a short bow.
The new string is only 8 strands, (the old was 12) I added in an extra two at the loops and 4 at the centre serving to bulk it up to feel right on the fingers and to fit the arrow nocks.
It shot nicely, it's hard to say if it made much difference but there were quite a few longish shots which I did well on.
I went round with a couple of visitors one shooting recurve and one shooting a takedown target bow, all similar draw weight. My little primitive was slower of course, but we all scored quite well.
I asked one of the guys to hold the bow while I went down into a ditch to pull the arrows, he commented how light it was.
We had gorgeous weather and one chap had bought his wife along, she enjoyed the walk and very kindly kept score for us.
(The Hazel bow is on my website 'delsbows' if you want to see it)
PS.
I just checked the club website, it turns out I came 3rd of the club archers who generally shoot longbow. The guy who won was shooting an AFB (American Flat Bow) which is faster and has an arrow shelf, he will doubtless be subject to much ritual abuse for his efforts.
I shot 376 on 30 targets. Max would have been 600, I generally recon on 10 times the number of targets being ok. Not that I worry too much about the scores as there is some luck involved.
EG.
There was a tiny paper target of a Rabbit tucked behind two trees, I had an arrow just kiss off the tree, smash and clatter into the other arrows. Damn I though, no score, missed it with 3 arrows.
As I was looking for the broken tip of the arrow (so I could re-use the point) I noticed 1/4" of shaft sticking out of the target dead centre!
I managed to pull it out, I'd scored a 3rd arrow kill! Actually I find it hard to figure out how the arrow broke yet penetrated so far. Maybe it glanced off the tree, penetrated the target travelling at an angle and the shaft then whipped sideways and snapped, maybe helped by bending against one of the arrows already in the target?

Saturday 24 September 2011

Nearly There

40 pounds at 25.5"
It's just down to a little tweaking, cleaning up all the rasp marks & tidying the back with a file and scraper.
I'll slim down the tips and add decent nocks too.
The right limb looks to come out straight from the grip and then kink down a bit, I think it's probably a bit of an illusion, due to a small knot, but I'll have a carefull look.
Overall the tiller is looking pretty good, it's too late to do much adjustment now, but the last few inches of draw will give me a chance to just smooth it out a whisker.
The twistiness doesn't seem to be causing any real problems, but I'll only really know when I start shooting it.
I've glued a chunk of Waterbuffalo horn onto one nock, the other is still the temporary scrap of softwood.
I won't try and get it done for tomorrow as it will need some shooting in and tweaking to get the best out of it. Those twisted limbs may well still settle dow a bit too.
I'll have to decide which of my other bows to shoot tomorrow, probably the 50#Yew longbow or my trusty little 40# Hazel

Friday 23 September 2011

Slow, but good Progress

I've been slowly getting it back to a low brace (about 4") and pulled it back to about 35 pounds. As I said earlier, the two main problems are getting the draw weight down without running out of heart wood and keeping good string alignment despite the twist.
I've been working down the sapwood on the back to bring down the draw weight, I've been attacking it quite roughly with a coarse rasp, but taking care to keep it fairly even, then cleaning it up with a finer rasp.
Basically I'm decrowning it and then following round towards the edges of the bow following a ring or maybe one or two above the layer where it's decrowned. The finished effect will be one continuous ring meandering down the centre of the back with a few rings showing either side and then a continuous ring out twards the edge of the limb. I'll post a pic when it's finished so you can see what I mean.


I've also worked on narrowing/aligning the tip so it looks ok at about 15" of draw. You can see the alignment with a taut string, it's pretty good, but the shot of it on the tiller viewed from the right side shows how the limb tip was kicking out to one side mostly due to the twist. The work on the tip and some carefull tillering has improved that considerably. In the shot of the bow on the tiller you can see the twist on the right limb if you click on it to see the pic full size, it makes the tip half of the limb appear too thick.
You can see the curve of the two limbs is more even now compared to the previous post.
With a bit of luck I might have it shooting tomorrow in time for the end of month 3D shoot at the club on Sunday. I'm not going to rush it though.

Thursday 22 September 2011

On the Tiller

It's just flexing, that's about 35 pounds pull on it in the pic. It's reasonably symetrical, I had to take a bit off the belly of the right limb and decrown it just a whisker near the handle mostly to get to this stage. I also plugged a small oblique knot which looked sound on the belly but was surrounded by a thin black line on the back, previous experience has taught me to pick away at the black stuff and really see how deep it goes.

The right limb is still a bit stiffer than the left, but this is the start, the next real step is getting the limb tips back to bracing height (just another inch or so) and shortening the string.

I've narrowed the tips a bit and improved the alignment of tips and handle.
I'm resisting the temptation to remove the hint of deflex near each end and to remove the twist, I'm keen to build it clean simple and honest and to let the wood do what it wants.
Doubtless more pics later or tomorrow, onwards and upwards, slow and steady as she goes.

Monday 19 September 2011

Decrowning

It seems that only one limb needs a bit of sapwood taken off so far. I've started decrowning it carefully going through about 6 growth rings with spokeshave, rasp and scraper.
I've managed to take a reasonable photo, having finally worked out how to stop the pale wood just bleaching out the shot (it was a RTFM problem).
You can see the alternating layers of creamy yellow and whiter wood, the white stuff is more crumbly and scrapes off fairly easily (You can see along the lower edge...) You can see that along the length of the limb the lines of the growth rings run along the bow. It's only near the grip where I go back to the full depth of the sapwood that the rings run across. The picture gives a good idea of what it actually looks like, not a job you can do for long periods without eyestrain! A little and often is the trick and to get the light right. Once the ring you want to follow is exposed , it's not too hard to follow it, but these are rather fine rings and it's easy to go plus or minus 1 ring. I'm just getting it about right, there will be plenty of opportunity to prettify it later.

Explain More!

Indeed, it's not really obvious what's going on, so I shall explain more.
To show the twist on the stave I've taped on some short lengths of thin cane (from an old roll down window blind, it's useful stuff).
With twist like that, you don't really know how it will react when the bow is being drawn back, so I need to get it on the tiller fairly soon.
I've previously had staves which looked perfectly straight but insisted on twisting when drawn.
On this one I decided to try to follow the shape of the surface of the log as much as possible. Some of the twist is due to my laying out the bow at an angle along the stave to avoid the two knots E.G. The bow sort of spirals around the stave,( but only by a matter of a few degrees).
The other factor is the asymmetry of the log. The central pith of the log was very close to one edge, where the grain is very dense, this can bee seen a few posts back, (There's a picture of a polished cross section of the log on the Yew Longbows page of my website). The effect of this is that on one edge of the bow the sapwood may be 6mm thick, but on the other edge it may be half that thickness.

The second pic shows the same limb tip viewed from either edge, you can see how although the limb is about the same thickness either side the heart/sap thickness is different. You can also see I've used a temporary tie on nock (this technique is used on some native American bows I believe) this is to avoid cutting grooves into the tips, as I want to keep as much wood as possible until I know exactly where the string will need to line up..
As I'm roughing out the limbs I'm trying to make the thickness along each edge about the same, whilst retaining a few mm of heart wood showing on the edge.
Now it wouldn't necessarily matter if the sapwood was breaking through onto the belly of the bow. I've seen several primitives with an edge of sapwood showing along either side of the belly, but these were from narrow saplings and were symmetrical, I've also seen some beautiful primitives with huge degrees of twist (but I suppose these would be seen as character bows).
Taping the spills of cane to the bow has done me a favour as it's shown that most of the twist is on one limb, (the 4 spills nearest the camera are virtually parallel).
Once it's on the tiller and being braced and draw the wood will settle down a bit and will find it's own axis to bend along. this may mean the grip rotates a bit from how it is at the moment. The important thing is that once it's finished it doesn't rotate during the draw. (Taping a spill to the grip and watching as it's winched back will test this)
This is a good reason for not actually clamping a bow during tillering, but allowing it to move freely so you can see what it's doing. Sometimes it's best to let the bow move how it wants and build it to blend in with that rather than trying to fight it.
We saw what happened on the last bow where I tried too hard to shift it to what I wanted.
I've just added that second pic, having done a bit more, it's up on the tiller now and is just flexing a bit at about 30 pounds with out any nasty tendency to twist.
I shall now check carefully over the limbs taking measurements and getting a nice even thickness taper, then I'll start serious tillering.
Hopefully it will all turn out fine, heat bending will be a last resort if there are major sting alignment issues.

Sunday 18 September 2011

Yew Primitive Progress

I put a loose string on the bow and put it on the tiller, it harly flexed at all, so I've been removing wood from the belly. I'm in danger of removing all the heartwood at some points so what do I do?
There are several options:-

1. Make the bow narrower.
2. De-crown the back.
3. Painstakingly take 1/8"-3/16" off the back following a growth ring.

I'll end up doing a sort of combination of all 3, I don't want to go too narrow and end up with a longbow shape, and the growth rings of the sapwood are very fine and would be a nightmare to follow.
Bearing in mind that my Hazel bow which is de-crowned is one of my best bows, I shall mainly go for option 2, but I will try to keep the growth rings tidy and I shall doubtless make it a tad narrower as I adjust the shape and alignment of the string during tillering.
The bow is likely to move a bit during tillering as it has some 'propeller twist' in the stave.
I've been working on it in short bursts over the weekend, but I've also harvested some Laburnum, it was standing dead in the garden but was a bit awkward to cut down.
It decided to fall whilst my wife was hanging out the washing and it fell across the line causing some consternation, the line snapped rather than twanging her into orbit.
The sapwood of the Laburnum was pretty manky and there was some rot at the bottom of the heart wood. It split nicely giving me one nice longish recurved stave and an odd deflexed bit with some knots. I've hacked off all the rot and got it into the garage (away from my other staves as I don't want any rot spreading). The ends have been painted with PVA. Hopefully in a week or so the remaining sapwood will have dried a bit and I can trim it down a bit more, check for rot and store it somewhere more convenient.

Thursday 15 September 2011

Yew Primitive Stave



I've started on a piece of Yew which I've been hoarding for ages, it looks like a perfect stave, but close examination reveals two awkwardly placed knots and grain which is very asymetric.
If I avoid the knots I end up with some twist or a bow with lateral bend which needs straightening at the handle.
I'm a bit fed up with heat treating and heat bending so I'm going to just make a bow fom the stave in hand, clean and simple and leave out the overthink!
The way to deal with knots is basically very simple, you leave 'em in or you cut 'em out. Of course you can't always see what dirction the knot goes in. I roughed it out on the bandsaw just leaving the edge of the knots visible so I could carefully remove as little as I could to take them out of the equation.
I'm aiming for a shortish flat bow similar to my Hazel bow (see the website), it will be narrower with nice slim tips, I'll probably radius the belly slightly to give a flatish oval cross section to the limbs I'm aiming for about 40 - 45 pounds but hopefully with little set.

Using the drawknife rips off wood quickly and also tends to follow the grain, some care is needed around the knots, but when a big chunk tears off it's actually telling you how the wood wants to be shaped. There comes a point however where discretion and a rasp takes over to avoid unwanted tearing.
Because of the weird grain on the stave the centre pith of the log runs in some peculiar places. Near the centre of the bow it's near the middle but elswere it's off to one side.
You can see the dark line of pith showing at two points on the limb nearest the camera in this last shot, just above my thumb and the further up and to the right.
There were quite a few drying cracks in the stave but they've dissapeared as I've got down to the centre pith. The cracks tend to radiate out from there towards the sawn face of a stave. They don't seem to run out towards the sapwood.








On this stave the sapwood is nice and thin so I'm hoping to just leave it alone having de-barked the stave carefully. This saves a lot of work following a growth ring and also adds to the nice simple primitive feel I want with this bow.
Some brown streaks of cambium still show, but these will be removed with a scraper in the final finishing of the bow.

Footnote(27/3/2014):- This eventually becomes Twister my favourite field shooting bow. Hopefully this note will help finding Twister when using the search facility.

Friday 9 September 2011

CRACK!

I heard an ominous cracking noise. The bow has fractured where there is a big S bend in the lower (left in the pics) limb. It's where there are a couple of knots, I'd been careful not to heat bend it at the knots and it's failed just beyond them where I did most of the straightening. The first two pics are with the bow strung to a high brace to open up the crack before I finally broke it.
It's been interesting working with the Hornbeam, but I obviously took on a bit too much with that stave. If you look back at the previous pics, there is no sign of a problem at that point

Once the crack appeared I took pics and finally took it to breaking point, it was still remarkably tough to actually snap. Overall I'm quite impressed with Hornbeam and will try again when I've got a straighter stave seasoned, I'm not too upset as it was always going to be a learning experience and it only cost me my time... well I managed to wreck my heat gun too (They are designed to be left standing nozzle up to cool down after use, but I left it on the floor in my haste to clamp up the bow during heat treatment).
Making bows is slowly curing me of my impatience and making me more philosophical about failure.

Wednesday 7 September 2011

Good News, Bad News.

The heat treating has certainly stiffened up the bow, but the bad news is some of the old lateral bend has come back due to the heat treating allowing the wood to relax a bit back to it's former shape.
Ideally one would heat treat and bend at the same time with the bow clamped to a form.
Well, that's ok in theory if the bow is nice and straight and you are just putting in simple reflex.
With a tricky shaped stave like this a bit of messing about back and forth is usually required.
Anyhow I have some other things to get on with while the bow settles down again.
I'm a bit more confident about it now as it's definitely stronger, I could barely get the string on it.
I think I can afford to loose an inch and a half of each limb if necessary too.
I'll have another go at it on Friday.

Monday 5 September 2011

Tiller Pic with update.

I pride myself on showing what I do 'warts and all'. Well here's a pic of how it looks unbraced and braced on the tiller. You can see it's awful, but the question is why?
I think the heat straightening I'd previously done had stiffened up certain parts of the right limb.
you can see the right limb is bending a lot near the handle and the left bending hardly at all at that point.
The usual way to tiller a bow is to mark the weak points and remove wood from everywhere else (and especially the stiff points).
I'm having to stiffen up that weak area with heat treatment and take out that slight deflex first as I can't afford to loose any draw weight.
It's not going to be easy, but hopefully I'll get it looking like a bow eventually.

I've heat treated the handle end of the right limb, here's a before and after shot (the after shot is the lower of the two)
I can't brace it and try it out until the limb has had a couple of days rest. What I can do is press on and get the rest of the limb, and the other limb heat treated... it's a bit of a slow laborious task, just as well I enjoy making bows!

Ready for the Tiller

The bow is now straight (that's to say the tips and grip are in line).
The first limb I worked was forced to be certain dimensions because of a knot in one area of the limb and the basic dimensions of the stave. I've evened up the thickness taper on that limb by staking the thickness near the grip and then the thinnest point and working out roughly even steps along every 6" of length (it worked out at 1.5mm change every 6").
I don't work slavishly to dimensions, what I'm trying to do is get a fairly even taper with no thin spots which could turn into weak points where the bow suddenly bend excessively (known as a hinge).
So with the stave having dictated the dimensions of one limb, I then make the other limb roughly match it, which is where I am now.
I felt the flex of the bow by putting one end against my foot, holding the other end in one hand and pushing against the grip (a bit like when you string a bow). It feels a bit soft for this stage in the proceedings, but there's no way I could have made it much different.
On the plus side, I flexed my 50 pound longbow and it felt similar, so I'm not too far out. The other good thing is the stave is still long and could always take an inch or so off each limb to get the draw weight up. The final trick up my sleeve would be to heat temper the belly.
Ah, but I'm getting ahead of myself, lets get it on the tiller and see how it flexes.
The second pic shows how I make a virtue of necessity.
One big knot couldn't really be in a limb, therefore it must be in the handle, which then takes on a slightly pistol grip shape:- Note the arrow pass is marked, and you may just be able to see the centre line marked on the belly.
Update:-
My suspicions have been confirmed, it's a tad soft and the undulations make the shape look weird. I shall do some heat treating and straightening/adding reflex.
I don't want to loose any length yet as you can't put it back on again!
If I do the heat treating now, it can have a couple of days to rehydrate the wood. Getting the limbs a bit more symetrical will help to see the true shape as it's drawn back on the tiller.
At one point I pulled it back to 30 pounds at about 27" on a low brace height...that's just too weak. The top limb looked to have a horrible bend just above the grip, but as I let off the tension I could see it 's just the shape of the stave.
The doesn't seem to be any set at all (hardly surprising on a long bow at 30 pounds...)
Off to the garage to break out the heatgun.

Saturday 3 September 2011

A Bit Straighter


After two bouts of heat bending, and some slimming down in between you can see it's much straighter now.
The aim is to get the tips and handle in line rather than straightening out all the bends.
I've also lost a bit of a deflex dip from the limb.
You can see the area I've heated by the discolouration. A bit of heat bending on the other limb and it will be in line.
The other pic shows me at work on the shave horse penciling in a line to follow the grain where it dips by a knot. I need to leave some extra strength there, but I don't want a great mass of excess wood, it's all feel/eye/guesswork.
By the way it's 76.5" long now, so I still have plenty to play with.
Iv'e got it back on the heat jig with the hot air gun blowing at 210C on the central portion of the other limb, a straightish section between two knots.
I don't want to actually try and bend it at a knot as that's a weak point and I don't want any aditional strain on a weak point. I'll leave it half an hour and then go and heave it into line and clamp it. A few days rest for the wood will be in order before I start really trying to see how if it will bend like a bow.






Friday 2 September 2011

Hornbeam

It's a lovely wood to work, the workability of Hazel with a bit of extra crispness, not a lot of visible grain, sot of Hazel with a hint of Beech.
The wood is begining to speak to me, but mostly telling me what it doesn't want to do!
I put a lot of heat and strain on it to try and straighten it a bit overnight, but it's not done very much.
I shall have to work down the limbs and correct the lateral bend when there's less wood to shift.
A couple of knots in the area I was trying to bend also need to be worked out, but if I remove them the limb will be too narrow at that point.
The solution is to move the narrow area nearer to the tip of the bow by sawing a few inches off that tip and moving the centre/grip area down. This works well because it puts the grip onto two other big problem knots and still leaves the bow taller than me (5'10").
That's why any character staves need to start a lot longer than the finished bow. More pics later in the day or tomorrow.
Update:- I've slimmed down the limbs a bit more and tested the moisture content on one of the offcuts, it was still up at 15% so I placed it in my sophisticated drying facility.
That's to say I lobbed it up on the south facing flat roof which is roofed with black rubber membrane and gets nice and hot. Later in the afternoon I got it down (mmmm tasty warm stave) stuck it back on my heatbending jig to try and straighten it some more. I'll leave it overnight, pics tomorrow.