Friday 29 April 2016

Damn!

The patch on the Yew heartwood primitive is fine, but as I took it to full draw I heard the dreaded "TIC" It took a few moments to find the culprit, a little further towards the grip another crack has appeared.
The bow didn't explode, so I'll maybe patch it and rawhide back it... or stick random bits of Yew sapwood all over the back (joke). Anyhow, it's not of deliverable quality now, but its taught me why we leave the sapwood on Yew bows and confirmed the received wisdom.
The secod pic shows how much I had to rasp out (and then sand on the end nose of the belt sander) to get down past the crack.
Pride comes before a fall and all that stuff. I'm a tad disgruntled, but I'm always happy to learn, much better to try it and see what happens than to just be another armchair expert.

Meanwhile on the 80# spliced Yew longbow I spent yesterday afternoon steaming out some of the deflex from each limb. It's a really nice shape now and I can see if the outers are moving now without the confusion of the deflex. I'll add some more pics later.

Thursday 28 April 2016

Patch, Perfectionism and the Spliced Yew

Doing that patch was a pig... I'd got a lovely colour and grain matched sliver of Yew but as I was thinning it down the belt sander shot it across the garage, never to be seen again!

I made another piece and got it glued in. The patch was fine but looked ugly, it was too pale and the straight edges stuck out like a sore thumb, so I chiselled out a very shallow wider channel leaving the bulk of the patch in place and this time extended it out towards the edge of the bow so the outer edge wouldn't be straight or parallel with the other. I still had hell's own job trying to get a colour match, just couldn't find the right piece of wood, if the colour was right the rings were way too fine and close.
I always keep the offcuts from the wood I'm working so that I can match colour and grain, but this bow is effectively the whole stave and the only decent offcut I had was already used for the first big patch over the knot that went right though the limb (upper right edge of pic). Anyhow it's done now and the grain match is good and it looks better without the two parallel lines. It's still rather pale, but may mellow down with age. Now I could have heated it to darken it, but that would have made it a bit harder and maybe less strong in tension so I didn't want to do that, or I could have messed about with stain, but I hate the stuff with a passion, partly due to having dodgy colour vision and partly due to the fact that the stain manufacturers have even less idea about colour! (E.G. What they call "mahogany" looks like tart's lipstick.)
Confession time, I mixed a spot of Mahogany, Indian rosewood stain and Danish Oil and gently touched over the patch, being careful not to overdo it. I think I've toned it down a tad, the stain still isn't fully dry so there's a bit of shine... I must let it dry and then apply some Danish Oil over it.
What really matters is, will it hold up? I'll give it another day to ensure the glue has fully cured before testing it. Patience comes easier to me these days.
Here's a pic, hopefully you all think it looks ok and I'm making a fuss about nothing!

Meanwhile I've been evening out the limbs on the 80# spliced Yew bow. It's coming back nicely from a low brace, the left (lower) limb is a tad stiff.
The right limb is coming round nicely, maybe a tad stiff inner third? The middle of the bow has been left slightly bulky to give plenty of meat round the slice and the grip and give it a chunky warbow look. It has some even natural deflex in it anyway which may be making the right limb look more bent.
I can start narrowing the tips and really cleaning up the back now.

Monday 25 April 2016

Accident Waiting to Happen

The Yew heartwood character bow was brought back today with an almost imperceptible crack showing on the back emanating from an innocuous looking pin knot. (In the first pic I've chiselled out a tiny bit to show the crack better)
I set to excavating a narrow channel following the line of the grain so I can let in a patch. As I chiselled down I could feel the wood round the pin knot wasn't hard clean and solid like the rest of the wood. I've gone down fairly deep over a reasonable length, but how to clean it up to an even curve so I can make a well fitting piece to let in? Ah! I remembered I have an old circular saw blade, I sharpened the teeth over section a couple of inches long (marked with masking tape) and used that, by hand, to clean up the channel to a nice even curve. I'll be able to use the curve of the blade as a template to shape the inlay.
I've done enough for now as it's fiddly work, slow and steady wins the day. Anyway, I'll need to fill the pin knot hole first as I've cleaned that out with a fine drill simply twiddled between my fingers.
In the pics you'll see the edge of the other patch on the limb, maybe I left that area a little stiff and it moved the stress onto the pin knot and caused it to crack, who knows? The good thing is that it was spotted in time and it's interesting that it didn't simply explode, a testament to the toughness of Yew?



Spliced Yew Billet Warbow

I've just started a Warbow for a guy 80# @ 29" which should be manageable enough for me with a bit of training up.
The spliced billets are decent wood and I made the splice nice and long, (see here:- http://bowyersdiary.blogspot.co.uk/2016/02/more-splicing-igor.html ) it should be fine for this sort of weight and I'll tiller it out to 30", possibly to 90# initially to allow for it to settle a bit. Warbows do tend to settle a fair bit as they are working pretty hard.
There is a bit of natural deflex in the glued up stave which is quite good as it allows it to be taken to brace a little easier. Reflex in heavy bows is a nightmare when it comes to the early tillering and trying to get 'em to brace as they try to flip upside down and can whack you on the hand as you are fiddling with 'em on the tiller.
I've got it roughed out and flexing on the tiller.



Saturday 23 April 2016

A few test shots

I took some video of the take down bow. After studying it I took a few scrapes off the belly here and there to tweak the tiller.
Video on Youtube here:- https://youtu.be/TLLn2wtDJNI
I shot a few test shots and it feels smooth and fast, it takes a good bit of force to brace it too. I may shoot it through the chrono or try it for distance once the flood plain dries out.
Here are a couple of pics, its all finished now and renamed Breakdown rather takedown!

Friday 22 April 2016

Dabbling About

I've got the 60 Pounder finished off and ready for collection.
You can see in the un-braced and braced pics the little bit of deflex bend just above the grip, this is visible still at full draw and illustrates nicely how you have to allow for the character of the stave. The overall deflex is pretty much the 1" it started with as a raw stave. The arrow plate is particularly hansome being made from the very tip of the horn which was used for the nocks.


Earlier in the week I'd been musing on what to do next and saw the broken Take down bow, I'd been thinking of ways of mending for some time so decided to have a go.

It had broken off the very root of the limb initiating where the bamboo back had been reduced to plug into the socket, this time I would leave the bamboo back untouched as much as possible. It still may fail as the dimensions of the joint are the same as before. Overall the bow is about 1 3/4" shorter, but the working portion of the upper limb is now almost identical to that of the lower which is quite pleasing. Usually the upper limb is a bit longer due to the grip extending 3" below true centre and only 1" above it.
This first pic shows my approach.
At the top is the broken off male part of the joint, I rasped away all the splintered wood leaving the clean bamboo and a little heartwood, blended back to the full limb thickness. A chunk of Yew heartwood was shaped up to glue in allowing plenty to re-shape the plug.
Second pic shows it half inserted in the socket. The socket is slightly tapered internally so as I gradually remove wood from the root end of the plug part it pushes in a little further each time.
Once finished the socket was good and tight, but once I applied a little wag and flexed the bow a few times while checking the tiller (which needed some adjustment) a slight fore and aft movement became apparent. I got over this by letting in a half moon shaped bit of horn a bit like a woodruff key at the heel of the joint, leaving it slightly proud ensured a good tight fit and the horn, being much harder won't compress in the same way as the Yew heartwood.


Monday 18 April 2016

Finishing and a Field Shoot

I went to Cloth of Gold's open shoot on Sunday, I shot pretty well but not as well as I'd have liked of course as I was tiring by the end. I was shooting in a group of 4 with whom I'd not shot before, a couple, both shooting sighted target recurves and a guy shooting an unsighted target recurve. It was very interesting to see shooting a different style and it gave me a better appreciation of the discipline and performance. They all out shot me as they all had a flatter trajectory, (the man, Lawrence, with the sighted recurve was drawing 50# and doubtless had an arrow speed well over 200fps) but I just about held my own with the unsighted recurve. My best shot, was on the longest shot on the course, which was a bear at over 50 yards which the others had missed. I hit it first arrow and Lisa, the lady of the group said, they'd all been embarrassed by a man with a stick! Made me chuckle.
Second time round (2x 20 3D targets) it was our last shots and I blanked it... even managed to stick an arrow about 10 foot up a tree!
Thanks to all at Cloth of Gold for a great day, the course was nicely varied, the weather kind and the catering excellent.

A quick bit of of 'back of the envelope' calculation about the long shot on the bear.
Say it was 55 yards, that's 165feet.
The arrow speed is about 165feet per second from that bow, therefore it's flight time is 1 second.
During it's flight it is free falling under the effect of gravity. How far does it drop in 1 second flight?
s=1/2 a t squared where 's'=distance.  'a' = accelleration due to gravity (32 feet per second squared) and t = time (1 second)
That gives 1/2 x 32 x 1 x 1 which is 16' (gasp!)
So no wonder I had to aim pretty high.

Meanwhile I've done the arrow plate and got 2 coats of Danish Oil on the 60 pounder and shot 36 arrows through it. It's looking good.


Thursday 14 April 2016

Yew 60 Pounder Almost Done


I've got the horn nocks fitted (pale Waterbuffalo horn) but not polished up. It's been tken to just beyond full draw (mind the brace height is a whisker low, which makes up for that).
The tiller looks lovely now, I had to do a lot of fine adjustment to get it back the last 3" and to get the mid-outer limbs working. The big knot was worrisome on the right limb, but I didn't want to leave it over stiff which would have stressed the inner limb.
I'll make a proper string for it, sand it down and get the horn nocks finished. Then it will be shooting it in and finally doing the arrow plate. It's always good to shoot it in first as the arrow pass may need to shift a whisker to get the smoothest shooting position. It looks a little weak about 1/4 of the way along the right limb from the grip, but that's just a bit of a deflex dip in the stave. It's a nice long bow, so it's not over stressed at 28". It would probably pull to 30 plus, but It's not rated for that because of the knots and shakes (there are a couple of areas still present, but they only go a mm or 2 deep and are soundly filled )
You can see from the picture it's a tad over the 60#, but that will doubtless settle down.
Here's a few other random holiday pics too!

Tuesday 12 April 2016

Honey I'm Home!


We've been on holiday to Madeira last week, we had good weather and a really chilled out time. I was in need of a break and I've come back refreshed.
Saw some wonderful plants, went up into the mountains and did a short walk along a Levada (an irrigation channel). In one of the gardens there was an exhibition of African Soapstone sculpture which I found very inspiring. We went on a catamaran and saw dolphins, fortunately the sea was fairly calm.
It was their flower festival on the last couple of days and I got some nice candid pics.
I like the one of the little boy being fussed over by his Mum, and the Slightly Japanese feel of the girl sitting on the kerb.


I'll get back to the Yew longbow tomorrow, it's probably ready for horn nocks.

I brought a second hand kindle off E-bay and I'm V impressed, it saves on carrying loads of books on holiday.
I was searching through the free books and found this. It's a must read and free!
http://www.amazon.co.uk/Hunting-Arrow-Saxton-Temple-Pope-ebook/dp/B00AQMBRHW/ref=pd_sim_351_73?ie=UTF8&dpID=51wS8T79noL&dpSrc=sims&preST=_OU02_AC_UL160_SR107%2C160_&refRID=0HH9E9CARP5QC7TG6KV1

I have a tatty old paperback version.


Saturday 2 April 2016

60 Pounder Coming Along

I've been rather busy with other stuff but I've been teasing the 60 pounder back, I've filled some small knots and been carefully working down the knot near the end of the right (upper) limb. The stave had about an inch of natural deflex overall, that is to say with the tips on the floor the belly (at the grip) was 1" off the floor. The tillering and working the bow had increased this to about 1.5"
I strapped the bow down (back down), straight with a couple of bits of hardboard under the deflex portions having first covered the sapwood with layers of masking tape to keep the heat off. The hardboard helped to force it into a slight reflex to allow for it springing back after heat treatment.
It's just about straight now with tips and grip touching the floor together. By the time it's finished it will be maybe back to 1" which is good. Un-treated it would have crept up to about 2" which would have been loosing performance.
I may do a hint of reflex towards the tips later, but it's a good honest shape now with a bit of waggle just above the grip which is still visible when loaded up to 60 pounds. A bow at full draw should still reflect the shape of the unstrung bow, that's what makes tillering character bows particularly tricky.
This post of a bow with a real dogleg shows what I mean:-
http://bowyersdiary.blogspot.co.uk/2013/04/belly-patch-bow-full-draw.html

It's getting close now, 60# at nearly 24" (at a low brace height ~4").I need to get the outer 1/3 of each limb coming round a bit more, but it's tricky with that big knot... It needs to work but not to get over stressed.
I see some horrid tillering where people leave a knot proud on the back (which is correct) but then make it proud on the belly too which just leaves it ludicrously stiff and creates a weak spot either side of the stiff spot. If the back is proud and the belly stays in line there is already extra thickness and stiffness and if there is no knot just a bump, the belly should follow the shape of the back.
If anyone is in doubt, they just need to measure the thickness at the bump and cube it. Measure the thickness below the bump and cube it. Comparing those two figures will give some indication of the relative stiffness of the two areas, it needs very little extra thickness to stiffen an area.
(Other opinions may vary, terms and conditions apply)