Monday, 28 March 2011

Test Shots

The tillering string has been twisted up to give a good high brace and I've shot a couple of dozen arrows, with some slight tweaking on the tiller in between. Even with the wooden toggle on the string it shoots smooth and sweet. Here's a pic showing the upper limb and the areas where the grain swoops up and down and had caused some problems. I must confess to removing the 3 arrows which hadn't grouped so nicely - but I blame the tillering sting for the odd poor loose! The bow has taken very little set; held with it's belly against a wall I can only get one finger between the wall and the grip. The arrow pass corresponds with a slight bend/bulge and a knot which shows on the back of the bow and is a nice little feature, (the slight bulge can be seen at the lower left of the picture) and gives a slight natural comfortable shape to the grip area. I'm resisting the temptation to tinker with it anymore. I'll just shoot some more arrows and then do the horn nocks.

Straightened Bow

The Yew longbow has come off the straightening jig and it looks much nicer, the sideways S shape has gone. I'd also taken some deflex out of the top limb, this has upset the tiller with that limb now appearing too stiff. Actually this is a good thing as it's allowed me to shape more carefully around the major dips in that limb. The bow is now back to 52 pounds at 28 inches and looking rather fine, very little set but some nice ripples of character. It needs plenty of shooting in to make sure it's settled down, before I do the horn nocks. There's still a little bracing height to play with and I can still take a tad off the length if it becomes necessary. Fine finishing and some shooting in is now the order of the day, hopefully I'll have it finished by next weekend when I can take it to the club and try it field shooting.

Saturday, 26 March 2011

Heat Straightening/Bending Jig

This is the jig I use for straightening up bows. (If I'm bending sharp recurve at the tips I'd use a curved former). It's just two bits of 4"x2" screwed and glued together with holes drilled in an ad hoc basis to provide positioning/holding. Scraps of wood are placed uder the bow and its gently pulled down into position. You can see the wet looking area where the linseed oil and heat was applied. If I remove the bolt at this near end the tip springs back up by an inch or so (originally it was 2 or 3 inches higher). I checked it this morning, but I've put back the bolt and I'll let it sit for a few days. The second pic shows bolts with lengths of hose pipe used to locate the bow and wooden offcuts used as wedges to hold it firm.

Friday, 25 March 2011

Perfectionism vs Pragmatism

The bow shoots nicely but when braced, but if you look along the back there is a slight S shaped curve. I couldn't decide if it was acceptable, so I showed my wife. She's not a bowyer but she has good eye for these things and will give an honest opinion. "Well, there's character and then there's too much character" she opined. It's not really what I wanted to hear, but it was what I felt myself really. Plan B. I mounted it up in my heat treating jig to correct the worst curve and also remove the deflex bend in the upper (right) limb, just left of it's centre (you can see it in the previous post). The area to be heated was coated with linseed oil to stop it drying out too much and to help conduct the heat. I then stood slowly moving the heat gun (at 250C) back and forth over the belly for an hour (The back isn't heated). Rather boring but at least my wife bought me out a cuppa. Now comes the hard bit, that's waiting for 3 days to give it plenty of time to cool/settle/rehydrate! Will it have improved matters? Only time will tell, I didn't actively try to remove the twist, just the bend which the twist had initiated. I applied the heat to one area where there is a sharp ripple in the grain, hoping to de-stress that area and hoping that it might alleviate some of the twist of it's own accord, I won't really know what it's done until I take it off the jig and cautiously flex it. There's a fair bit of guess work involved as it very difficult to judge the bend, mainly because there is no good solid frame of reference. The string is a straight line reference, but it's not a plane, the back of the bow isn't a consistent flat plane, or even a consistent curved surface in this case, indeed, that's what caused the problem in the first place. I suppose the back of the bow at the grip could be considered a plane of reference, but it's hard to visualise short of glueing a sheet of perspex to the bow at that point!

Twisting Bow?

I've spent most of the day coaxing the bow back to full draw 54 pounds at 28" (still not quite full bracing height, but close enough).
It was my first day working at it outside this year, glorious day, sitting with a bow, rasps, files, scraper and a mug of tea. The hedgerows coming into bloom and my first sighting of Bombylius Major in the garden which always makes me smile.
There is some natural twist in the bow and a wee bit of sideways curve. The big question, does it twist as it's drawn back?
I taped a couple of spills onto the ends of the bow and got them lined up, winched it back to full draw and they pretty much are still in line. This indicates that the twist is remaining consistent through the draw and it's not missbehaving.
Here's a shot of it unstrung and at full draw, you can see some of the character in the bow.
At full draw the left limb could do to curve a tad more where that slight hump is.
I've still got a few pounds of draw weight to play with (target weight is 50 pounds), it's not quite to full brace height yet and I may also take a whisker of the length when I put the horn nocks on, so there is room to tweak that left limb a bit.
The other question from yesterday is does the limb bend sideways? Well ,there is a very slight S shape to the bow but it seems stable, I'd expect sideways bend to also show as twist which would be seen in the pictures above. I have shot a couple of arrow from it, but it still needs a fair bit of finishing before I can really see how it shoots.
The knot I plugged has almost dissapeared as I've worked down the bow. I had intended to leave wood all around it but now only a sliver remains.

Thursday, 24 March 2011

When is a Mistake a mistake?

A guy on one of the forums (fora?) had looked at this blog and asked if I still make mistakes after my years of experience or if I hide them.
It's a very good question but it rather depends on what you consider a mistake!
The longbow I'm working on at the moment has some natural twist and a few wiggles, now with hindsight I'd have left the sapwood thicker along one edge rather than following the growth ring, this wood have made the back of the bow flatter rather than sloping such that one edge of the bow is thinner than the other due to the twist.
Having one side thinner tends to make the limb twist even more and it tries to bend sideways.
This begs the question 'did I make a mistake'?
Well I s'pose it depends on if the bow turns out well.
It's not an exact science where 2+2=4
Sometimes 2+2 can equal 1+1+2 as there are many ways of achieving the desired result, some will be prettier than others, some will give a faster bow, some maybe a more rugged bow.
As a (rather contrived) example if a limb is exactly 6 growth rings thick, but the rings aren't uniform and the bow is 0.5" thick on one side and 0.7" thick on the other what can you do? well you can thin the 0.7" side down to 0.5, this could be done on the back or the belly.
You could make the limb narrower to minimise the discrepancy as presumably somewhere in the middle it's 0.6" thick! But if you make the limb V narrow it will be even more likely to bend sideways.
Anther thing would be to move the centreline of the bow across to try to counteract the tendency to bend sideways, this is done by shaving away one edge of the bow and re filing the nock groove as necessary... ah, but both these solutions involve narrowing the limb tip, thus any narrowing may well be doing two jobs at once and produce a dramatic effect (on the other hand it may do nothing!)
So you see often it's a matter of making small changes, each trying to rectify the problem, sometimes one change will have an effect elsewhere or a more dramatic effect than anticipated.

Of course there is always more drastic action, say cut 3" off the offending limb tip and move the grip along to compensate (I usually make a bow 2" longer than the target length to allow some room for maneuver).
As a final resort sideways bend can be removed with heat.
I believe some twist can also be removed with heat, but it is generally considered to be more trouble than it's worth.
A bit of twist isn't a problem as long as the bow draws back smoothly in a consistent plane, what you don't want is a limb which moves progressively sideways through the draw, although I daresay it would still throw an arrow!

So have I made a mistake with the longbow?
I don't know yet!
It's pulling back to 50 pounds at about 22" at a low brace height. It's behaving fairly well but I'm having to keep an eye on the sideways shift, the one thing in my favour is that as I work the bow down the irregularities and imperfections are being reduced at each stage.
In fact a tiny bit of asymmetry in the bow can be useful, if the string tracks slightly to one side this can be an advantage if it's nearer the arrow pass and thus giving a bit more of a centre shot, the bow would be said to be right handed or left handed.
There was much discussion of this on one of the archery sites where some people though this was a lot of nonsense, however, these were generally people who weren't used to making self bows and having to accommodate the peculiarities and whims of the stave.
I hate the term 'expert' but if I'm forced to define it I'd say an expert is the person who can put right their own mistakes.

Monday, 14 March 2011

More Yew Longbows

I'm working on my last 3 Yew staves. This one has some character with a few nice swoops up and down in it, and some natural reflex (Although this will doubtless get pulled out during tillering).
There was a smallish knot too, it looked insignificant until I tested it with a small screwdriver. It was manky, I cleaned it out with a combination of screwdriver, drill, my nice fat permagrit needle file and one of those big thread cutting woodscrews, they have quite a sharp thread and it was v good for scraping out the bad wood. It's important to get back to clean wood.
No good trying to glue a peg into rotten wood. It made me feel a bit like a dentist.
I fashioned a tapered wooden peg from a scrap of nice dark Yew by roughing it out and then turning it in the pillar drill.
The bottom end of the peg is supported in a hole drilled in a scrap of Oak with a bit of beeswax in it for lubrication, the pic shows my poor man's lathe in action. I used a tapered peg and hole as it gives a tight fit when tapped firmly home.
The sap wood on the back of the bow has already been carefully worked down to be just 2 growth rings thick, which is looking quite attractive. Maybe one day I'll try going down to one ring, but perhaps that's just crazy talk.
I've stopped using the drawknife and gone to the spokeshave and rasp now, there are a couple of areas by knots a swirls in the grain where it tears with the spokeshave and it needs the rasp.
I've put the long tillering string on it and pulled to 50 pounds, it barely straightened out the little bit of reflex, so I've obviously got a fair bit of wood to remove still before I can even start to see the curve of it.
P.S This isn't the same stave as in the previous post.

Monday, 7 March 2011

What the?

The Yew stave I debarked yesterday felt a bit funny and the wood under the bark didn't look white enough... I just put it down to bad light.
When I roughed it out on the bandsaw I saw what was wrong... The sap wood is a third of the way into the log instead of under the bark! (It's that nice white stripe).
Now this stave is from the same log as the bow in the previous posts! It just goes to show what weird stuff wood is, further down the stave there appeares to be no sapwood at all!
I might save this stave for a bow for myself as I've decided against reworking my 75 pound bow (I wouldn't want to risk ruining it, and it would be very tricky due to the various knots, twists and turns.)
I'll remove that outer 'heart wood' but I don't know how it will look as it gets worked down. All I can do is follow a growth ring and see what turns up.

Sharpening a Bandsaw Blade in situ!

I've been tidying the garage which is my workshop and taking stock of my staves. I've only got about 3 bits of Yew remaining and some Hazel that I want to have a go with.
I wanted to get the last bits of Yew de-barked and roughed out, however the bandsaw blade is badly worn. Ripping through wet hardwood soon takes it's toll, the points of the teeth were more like knitting needles than chisels.
I found this article on t'web where this guy had sharpened his bandsaw blade, he'd made a wooden holding fixture and used a Dremmel tool with a tiny grind wheel.
Well, that looked seriously slow to me and still involved taking the blade off and on, which in my case also means moving the bandsaw as it's tucked behind my table saw.
Why make a holding fixture when the bandsaw holds the blade nicely anyway? Nothing ventured nothing gained, so I put a small grind wheel (about 2" diameter) in my electric drill and just touched it to the sloping back of a tooth, it ground away enough to clean up the cutting edge and the downward pressure moved the blade down slightly.
The blade is only 3 teeth per inch and you wouldn't want to try it on a finer blade as there wouldn't be enough room between the teeth and there would be too many of 'em.
I got a decent light onto the job and set about it. Once I got the feel for it I could give a quick touch to each tooth, changing the angle of the grind wheel for alternate teeth and occasionally helping the blade around. I'd marked where I started with a bit of masking tape and it seemed forever before it reappeared, but it was only 15 minutes.
I tested it out and it cuts ok, it wanders a bit more than a new blade, but it was fine for roughing out my next Yew stave.

Friday, 4 March 2011


I've mended the quiver, not without a few errors in the stitching which required it being done twice. Oh it's so easy to find you've stitched through an extra layer of leather.
As I was doing it I looked at the poor old quiver made of bits of old school bag and assorted discarded handbags donated by my wife and thought the whole thing was rather cobbled together. Ah, yes indeed, the penny dropped, stitching together scraps of leather is doubtless where the expression came from.
It can't be that often an expression is genuinely used in context these days, although we get a fair few from archery.
It would be handy to have leather working as another string to my bow, and I'm considering buying some leather to make myself a decent quiver. I've also enquired on the cost of having a custom quiver made to my own pattern, I'll have to do a cost benefit analysis (just a bit of joke management speak there).

Thursday, 3 March 2011

What a Muppet

Oh dear, My old quiver,( made from my old school bag!) is falling to bits.
I cut a reinforcing patch to strengthen where one of the straps stitches on. I glued it on with a spot of UHU glue to hold it in position while I punched the holes.
I then and stitched it in, stopped to admire my handiwork and realised it was...
ON THE WRONG SIDE so it would be left handed.
It didn't take me too long to do and I actually laughed about it. I enjoy stitching leather, but it's just a healthy reminder to pay attention in class.

It won't take me long to do it again on the right side.

Full Draw

This is a pic of full 31" draw after a bit of tweaking.
Initially I got my wife to take a pic of me at full draw with a 31" arrow but it didn't look quite right, I could see the nocking point was a bit high and the lower third of the bottom limb was a whisker stiff, this was probably accentuated by the longer draw which I hadn't really had a good look at before.

I popped into the workshop moved the nocking point down and took a few light scrapes off the belly of the lower limb near the end... (That's 4 coats of Danish oil which need to go back on now damn!)
Took another pic and it looks spot on now.
All this shows the typical bowyers tendency to worry and over analyse, constantly looking for subtle errors in the curve. It also illustrates the importance of knowing when to quit and when to be true to your own instinct and just do that tiny bit more.
The second pic shows it unbraced, you can see that there's very little string follow.

The red serving on the string isn't my usual, I had to redo it with a thinner serving as the arrows were a bit tight on the string. I'm sure that's why my shooting was so average on Sunday (cough splutter).
I bought a string serving tool which makes the job much quicker and is much kinder on my knuckles which would always ache a bit after making as string.
I'd not used a serving tool before and the instructions were almost non existent, however there were a couple of videos on Youtube which showed one being used which got me up the learning curve, although the finishing off of the serving is still one of those jobs which would be easier with three hands.