Wednesday, 31 January 2018

Pair of Hazel Primitives

I've been finishing off the lower weight primitive and teasing back the heavier one to full draw. The make for an interesting comparison, the lighter one has a heat treated belly, the heavier is a whisker longer and broader.
The lower pic shows how the two bows were sitting when in the tree, you can see the slight bend at the far end still evident in bothe bows.

The shooting machine performed very well last Sunday and I've been studying the video so that I can maybe make some slight improvements. The main arm of the machine flexes slightly, but that's not necessarily a bad thing, as an archers arm definitely has some flex. There is a lot of sideways movement in the string and I think the nock of the arrow and the string may just be contacting the track on which the trigger mechanism draws back.
We tried a couple of flight arrows and the one which went substantially further flexes alarming under the acceleration, it's clearing the bow by about 1", but the nock end smacks against the grip.
Here's the video:-
Got some nice video of my mate JT, loosing a 130# warbow:-

Been busy with odds and ends today, made up 5 gallons of Dark Velvet Stout (from Wilkinsons) for my winter beverage. Walked up the town to do a spot of shopping and bought a small plastic tool box from Poundland, just the job to keep the shooting machine accoutrements in.

Took the pics and typed this up of course too!

Friday, 26 January 2018

Another go at the Hazel Primitive

I've spoken to the guy for whom I am making the bow and he really wants 40-45# so I'm making the other half of the log into a bow. I'm not using the draw knife this time, it's straight from bandsaw to spokeshave.
The stave has a nice feature, a deep ridge on the back of the upper limb, at mid limb. To get this area flexing I've scooped out the belly making it concave to match the ridge, it will look great on the finished bow.
An alternative approach would be to de-crown the back, e.g. To plane off the top of the ridge, however this would run the risk of the back lifting splinters. De-crownibg can be done but it needs to be even and consistent along the whole back, not just at one point.

It's tricky to get a decent picture showing the ridge, the scoop shows better.
Here's a video of it on the tiller.

As the bow is being tillered the bark starts to crack off where there is most movement, this is like nature's strain gauge. If the cracks are evenly spaced along both limbs, it's a good indication that the limbs are both working in balance.

Thursday, 25 January 2018

Mk2 Shooting Machine

The shooting machine is finished now.
I haven't done any test shots yet but I have mounted a relatively heavy bow and pulled it back testing the sliding latch and pulley system. I also tied the rope round the bow mounting clamp threaded it through the pulley and heaved as hard as I could with both hands, which must have loaded it up to a couple of hundred pounds.
One clever feature I've added is a magnet incorporated into the end stop at the top end of the track, this holds the sliding carriage at the top end ready for cocking the bow.
I've made the little wooden block that lifts the trigger as it reaches full draw and I've drilled holes so that can be set for 24",26", 28", 31" or 32" draw.
Looking forward to testing it at the weekend weather permitting. (Pic with Emily cat shows how it breaks down to two parts).

There has been some comment on a flight archery group where most people have approved of the machine but one bloke maintains that shooting machines are useless except for comparing bows at 3 foot range. Dunno if that even makes any sense. Sure it won't accurately replicate a human loose but at least it should provide a consistent platform to allow comparisons. Anyhow only time will tell, and I'm sure some work could produce a trigger mechanism that reasonably replicated a human loose by adding some friction into the pivot and some flexibility and length to the ends of the fingers of the latch.
I've learnt to rely on my own findings rather than the opinions of others, anyhow I don't s'pose he was testing heavy English longbows.

Meanwhile the Hazel primitive is progressing and needs me to check it out at full brace height and full draw then I can make a string and shoot it for about 50 arrows to let it settle in before any final tweaking and doing the grip.
Ah! Just checked it and it's only 35# @28" . The cleaning it up and taking out the tool marks has lost a couple of pounds. (bugger)
I could try re-doing the heat treating long and slow, or it might still be an acceptable weight. Failing that, there's a lady archer who is a coach and shoots all styles who hasn't got a primitive. I'm sure she'd like it.
I do have the sister stave to that one so I could make another (with a little more patience in the roughing out). This illustrates nicely that you can make a bow quickly, but not necessarilly to a precise draw weight. Those who suggest you can make 'em by numbers and make 'em like shelling peas don't know what the draw weight is until it's finished.
Of course I could have kept my mouth shut and my head down about this coming under weight, but it reminds me of why I usually aim to make 'em to the upper limit.
It's easy to take off weight, it's very hard to add it on.
Using a string from my other Hazel bow I had 3 test shots at a slightly tentative 27" draw, I then tweaked the arrow pass a bit and had a fully committed shot at 28", the arrow flew lovely and true.

Tuesday, 23 January 2018

Rapid Progress on the Hazel Primitive

Seeing as how JT's bow that he's doing under my watchful eye is Hazel, it seemed appropriate that I should be working some too.
I was soon was reminded of it's propensity to tear out when using a draw knife if not used with caution. I also realized that the draw knife needed sharpening.
What the wood can do is to take off a nice long wide sliver, but the sliver will also pull out a narrow strip underneath it too which isn't apparent immediately! It looks a bit like a tongue or groove on a T&G board. (Note:- this is very well seasoned Hazel see pic)

Of course I panicked but I was relatively sure that I'd left enough wood to get away with it... I moved to the spoke shave after that which took off much more even shavings with no tearing.
As I was tillering the bow it was evident that there was a weak area on the lower limb, so I reversed the bow making that the upper limb. That's why one should never cut out too much from the grip early in the process, it gives you room to shift the grip and limb positions slightly to suit the wood and ones impetuous use of the drawknife!
A bit of adjustment including an inch off one limb tip (yup, that's why you always make 'em an inch too long) and the tiller was looking good.
The draw weight is a little lower than I wanted, so I strapped it up and heat treated the belly, which give the Hazel a nice colour and hardens it a little. The heating also allowed me to pull out a tiny little deflex bend at one tip.
As I flexed the bow the bark was cracking, I picked it off to reveal some nice clusters of feature pin knots.
The target weight for the bow was  40-45#, it may come in a whisker under, but it's better to have a fast well tillered bow than an uneven over-stressed slow one that's 5# heavier.
Anyhow, the guy who wants the bow is getting back into shooting after some health prob's so a pound or two under is probably a good thing.
We'd been discussing "authenticity" as he wants to use the bow for target and reenactment in an Anglo Saxon setting and apparently there are "authenticity Guidelines"... I'm sure you can imagine my reaction to that concept! I don't believe there are any surviving Anglo Saxon bows so I'm assuming anything from the Meare Heath to the Hedeby style would be appropriate, but quite how anyone can pontificate about nock styles is beyond me!
Anyhow I'm going self nock, big one at the bottom that can also accommodate a stringer with a rounded end to take the inevitable contact with the ground (see pic) and a long pin nock on the top with a binding of linen & glue to form a ridge that a stringer can sit on.
Should look good. I'm making my usual modern continuous loop string for reliability and a consistent brace height and he can get a linen string from Hilary Greenland, which will be better and cheaper than I could make as I'd have to buy in the materials.
The bow is at a low brace and is coming along nicely... oh yes, the other detail is a veg tan grip. I'll see how I think that will look before cutting leather, but it could look good.

Sunday, 21 January 2018

Roughing out Hazel Staves

My mate JT came over to do a bit on his rapid seasoned Hazel stave as it was too cold and wet for shooting.
We couldn't run a clean straight line down it so marked it out as 2 straight limbs with about  8 inches between them where we'll make a bit of a bend (with steam) next time (Right stave in the pic).
Just deciding where to reduce the stave from 7' down to 74" and where to lay it out took some time. Spent some time trying various tools too, drawknife, spokeshave and axe. The stave is flexing now, but we can't try it on the tiller until the sideways bend is sorted.
Pic shows JT scraping off the bark so we could mark it out more easily with a pencil (note mug of tea and biscuit, vital part of the bow making process) Marking the back allowed the flatter sawn belly to rest on the table of the bandsaw for easier cutting.
Bit of a shock when we came out of the garage after about two and a half hours as there was a good layer of snow!

I had a request for a Hazel primitive from a guy on Archery Interchange, I wasn't that keen at first, but once we got chatting via E-mail it piqued my interest so after lunch I got that roughed out from a well seasoned stave.
The stave has a nice bit of reflex/backset so it should make a nice punchy  bow with a little luck.

Been working on the mk2 shooting machine too, it is vastly improved... hope to get it done for next weekend, assuming the weather is good enough for shooting.

Sunday, 14 January 2018

Shooting Machine

I've modified the shooting machine to be the mk 1.5 . It can now be shot in a more stable manner with a foot on the back end holding down and drawing the bow by pulling on  rope which runs through a pulley.
I took some video, using my new camera with slo-mo capability, of it shooting twister using a regular field shooting arrow and then a flight arrow.
JT took some video of me susing the shooting machine, from which I took a screen grab to show how it works.
I also took some video of my mate JT shooting a warbow at 300, 600 and 1200 frames per second.
Video of the arrows leaving the shooting machine.
Video of Warbow shots

The camera and the shooting machine were a great success. The machine needs some improvement but it certainly proved the concept.
I'll produce a mk 2

Thursday, 11 January 2018

Bow Collected

Martin came to collect the Yew bow and brought Ridgeback, the one I'd made him back in 2012 to check the draw weight.
It was great to see how Ridgeback had matured to a lovely colour, it was interesting to see the bow as I'd made the grip deeper than I'd remembered with quite a high arched D section giving it a slightly Victorian look, but only over about the central 10" or so. It also felt remarkably light in the hand.
Seeing the two bows side by side showed the contrasts and similarities (Ridgeback is the left one in the pic). The top nocks are different but overall they look very much to have the same feel.
He shot a few arrows from the new bow, it looked nicely manageable and was noticably heavier than Ridgeback, which I checked as 55# at 28"
It was good to have a chat and to find that he's hoping to join Cloth of Gold field archery club (which I heartily recommended), so maybe we'll bump into each other up there some time.
He also gave me some beers as an thank you which was much appreciated, especially as I've just finished the Christmas supply!

I'd have taken more pics but the camera (the little Canon SX220) seemed to be playing up... looking through the settings I found the lens retract set to 0 secs, which seems a pretty bonkers concept and is quite likely the problem.
I set it to 1 min and it seems ok now, (hopefully).
Just had an E-mail from Martinn to say he weighed the two bows, Ridgeback weighed 580g and Wonky weighed 800g
That's quite a difference so it will be interesting to re-weigh 'em in the summer or in a year.
There is the "Mass Principle" which some people use with bows, which basically says for any particular bow, length,poundage etc there is an optimum weight. I don't use it myself, but the heavier draw weight bow does weigh more, other than that I can't really muster the enthusiasm to delve further into it. I can't really imagine that about five or six pounds of draw weight and half an inch weight should add that much mass. My guess is it's more about the state of the wood.
If you all sit patiently for six months I'll report back. (Sit still hands on laps, no fidgeting!)

Monday, 8 January 2018

Yew Bow Finished

By putting the bow against the other half of the log from which it came, you can see how much bending work I've had to do to get a reasonable shape. The bow still has a lot of character and it's difficult to really see how its flexing. I'll shoot 100 arrows through it and see how it settles. Maybe I'll stiffen the centre with a little heat treating, but that deflex area just above the centre is weird an make it look weak there.
I haven't done the arrow plate yet, but it's a bit chilly for shooting it in or doing the arrow plate at the mo'
It's a tad under weight, 60# at 28" but a little heating after it's shot in might improve that, mind I'm reluctant to risk inducing any sideways bend as I've had to fiddle about with it more than enough.
I'm pleased to say that although it started off looking a bit ugly, it now looks graceful and elegant.
If we get a mild spell I'll get some video of it being shot.
I've had 5 test shots from a decent full draw, it's a tad heavy for me, but it bangs 'em in. Last shot was plumb centre... nice!

Friday, 5 January 2018

Yew Longbow Nearly Finished

I've had to do some more heat tweaking and also had to fill a knot that goes right through the upper limb.
I've done the horn nocks and at last the bow is beginning to look good.
Here's a video of it on the tiller, it still needs a little work, but as it's only at a low brace, hopefully it will make the required draw weight (63# @ 27").
Meanwhile I've been tinkering on the lathe and I ground up a tool to put a 2mm radius onto brass arrow heads. I'd read somewhere that a 2mm radius is supposed to be optimal, but it could be nonsense. Having a shooting machine to do tests may prove it one way or another.