Saturday, 28 February 2015

BBY Longbow Gets a Work Out

The longbow shoots really well and fast too, it was a drizzly day but I went up the club and got some good shooting.
18 3D targets, well 17 really as I couldn't be arsed to do the last as I was tiring and I'd have had to wait to climb up a muddy mound as I was shooting with a group of mates and only one could get up there at a time.

The pic shows my last shot of the day. First arrow inner kill mind it was only at about 18 yards. I took the laser range finder so some of the guys could have a try of it. Not allowed to use anything like that at a real shoot of course, but it was interesting to check out our distance estimating skills, which turned out to be pretty good.
I'll fiddle and fettle the bow a whisker, get it on the tiller to check the poundage then do an arrow plate and grip.

Dunno if you will be able to see the arrow trajectory in the video...
I've had it on the tiller and it's about 44#. I must be below par fitness wise as it feels heavier than that, maybe the early draw weight is high. I'll have to measure the speed, see how it compares with other bows.
I've chrono'd it. I only shot 3 arrows:-
163.9
156.5
166.7
That confirms what I suspected... It's fast.

I had a few shots of the flight bow, it was disappointing, maybe it's over built and is really a 50# bow in disguise, or maybe I was just under drawing it...

Friday, 27 February 2015

First Test Shots BBY Longbow

Whew At last I've got the longbow shooting, I've had endless tweaks to get it behaving, but it seems very fast.
I'll try not to count my chickens before they are hatched though.
I put some masking tape round the arrow pass and shot it right handed, it seemed much faster than the flight bow, but then it it about 50# as opposed to 35#. Seems very smooth too.
I'm leaving it strung for a few hours and shooting more arrows through it to get it shot in.
There's a slight ping on a knot near the grip in the belly of the lower limb, I'll just keep and eye on it to make sure it stays stable. Pinches at knots are fairly common, a knot has a hard core and a thin layer of bark like substance, it';s like a branch growing through the parent wood. The bark has no real strength and will compress causing the wood covering it to buckle and form a tiny ridge. I've seen warbows where every knot had a pinch yet it was fine. Because the belly is in compression it's not a problem. However, if the bow was bent the wrong way the pinch would just crack open, mind bending a bow the wrong way is likely to break it anyway.
I've shot 40 arrows through it now.

I've been working on the flight bow too, getting the limbs coming back a tad more, especially the right one by reducing the belly mid and outer limb, also and taking some weight off the tips. It seems to shoot very true and it would be nice if I could tease it out to my usual draw length so I could use it at field shoots.
I might take it up the club tomorrow and see how how it shoots.

Thursday, 26 February 2015

Major Clear Out and Log Prep'

My mate Mick the Blacksmith came up with a haul of Yew from a tree surgeon he knows.
It's been lying on the garage floor and with that and the other stuff I can hardly move...
Time for a clear out. I took all my old golf kit, put it into storage and had a good tidy and sweep.
Then I tackled the Yew logs, I'd already split one short fat one into two nice 4'6" lengths (they are the two on the top).
Some of the others were a tad thin to try and get two staves so ran 'em through the bandsaw taking about 1/3 off the width, cutting away the 'bad' side. Some of the off cuts are clean enough to become Yew sapwood backings. The ends have all been painted with PVA ready to get up on my shelves tomorrow.
Having had a good clean up I'll be able to have a nice clear run at finishing the two bamboo backed bows I'm working on.

The flight bow is drawing about 35# at 23". I'll be easing off the tips and narrowing them, trying to get it back to 24" or maybe 26". I have shot it and it feels fairly quick with my 'standard' arrow. I videoed it, grabbed two stills and combined them so I can see how the limbs move from braced to full draw. It looks like the right (upper limb) needs to work a little more.

The 50# bow will have a good clean up, then I'll start shooting it for about 75 arrows and then I'll look at the weight. (I'm chickening out of putting it on the tiller until it's shot in)I've been discussing (moaning) with my brother who asked about the patch and what the draw weight is. He laughed when I said "I dunno, it is what it is. Nothing I can do about it now!" I'm expecting about 48# but as I explained to him, with most bows you are looking at about plus or minus 5# on the stated draw weight and I've seen plenty that have been plus or minus 10#.


Worst was one bloke showing off his 100# bow at the club, one of us old guys drew it with ease, I then had a go and told him it wasn't even 90#... he later measured it at 80# !

Tuesday, 24 February 2015

Whew!

I'd got the patch done last night, took the strapping off this morning before going to work and roughed it down a bit.
Home from work I've bended it in, strung it and it looks good, a little work here and there and I went for it a good full draw, it felt smoother and I was more confident. maybe I'm being fanciful or maybe I could feel that small knot binding up before.
Actually there was a pair of knots one going out to each side from the centre. You can still see a hint of the "good" one to the left of the patch.
Lower left in the pic is the start of the grip and you can see the darker wood where it's been heat treated. I didn't get a perfect grain match, but I was keen to use some of my fine straight grained Yew.

I feel I can press on now and get it finished. I'll be sure to give it at least a hundred arrows before I declare it fit for purpose. Once it's all polished and waxed it will look great with a relatively clean lower limb and some nice features on the upper. I Haven't measured the draw weight, but my guess is about 48#. The bow still has some reflex at the tips and a tiny whisker of set on the inner limbs, it seems to weigh nothing and I'm hoping it will be fast.

As it's for a left hander I may make a thumb ring so I can shoot it right handed but with the arrow on the right of the bow (as it will be for a left hander). The thumb release kicks the string the opposite way to the three finger (Mediterranean) loose.

NOTE:-
The lateral bend returned despite all efforts.
In the end I sawed it in half, re-aligned it and made it a take-down, see later posts.

Monday, 23 February 2015

Loads of Work

Both bows are progressing nicely.
The 50# longbow is behaving it's self now and I'm now doing the horn nocks.
My first test after the heat treating and minor sideways correction showed it pulling 40# at 24" . Some arithmetic shows this works out at about 49# at 28".
There was a funny noise coming from the bow, which is why I only took it to 24", but I think it was just the temporary nocks snagging the string, I cleaned 'em up and simply drew it to 28"...
Sweet as a nut!
I'm moving the top nock down about 1/4", it may help the draw weight a whisker and will just balance the limbs a tiny bit better... to be honest it's more about fiddling than logic. It takes out a tiny bit of the knotty area on that limb, which will look rather fine when it's polished up. The top limb has all the character in it, the lower limb is cleaner.



The RD Flight bow is looking good, I still had to do a slight sideways/twist correction one one limb. I have plenty of tip width to play with to tidy up the limbs to match the string line but it's pretty good now.
the pics show it braced, the string line and how I jigged it up for the slight sideways correction. I pushed the limb tip across about 3/4" and after correction it had settled down to about 1/4 - 1/2" shift.
You can see how the side pieces of hardboard contain the heat and direct it along the belly.

Hopefully I'll press on this afternoon and get the horn nocks done on the longbow and get it cleaned up ready for some testing.

Just got the top nock done. I couldn't resist buffing it up to see the feature knot.... mmmm nice.

For pities sake! Some bows are more trouble than they are worth... I put it on the tiller, just working up to 28" and I hear a CRACK! I let it down quick.
At first I thought the sound was one of the handle blocks popping, but close inspection revealed there's a fracture on the belly by a knot. Damn,
The bow is still sound, it didn't collapse, that's the beauty of Bamboo backing, it holds it all together.

I've rasped out the offending knot/crack over about a 3" length and down to about 1/3 the depth of the belly. I'm going to cut a suitable patch, heat treat it and glue it it... one hell of a lot of work. It will be a great bow when it's finished but one that I almost wish I hadn't started!
I've got the patch made and heat treated. I'll glue in on in a minute when it's cooled. I have a theory that maybe the heat treating and lateral correction stressed one of the small knots, because that's the area where both heat treating and lateral bend were done. I'll make sure the bow is clamped up nicely in line when I strap up the patch.
I'm sure it will all turn out fine... it's just odd how some bows almost make themselves and other you have to drag 'em kicking and screaming into a finished bow.

Saturday, 21 February 2015

Two Steps Forward One Step Back

The Bamboo backed Yew longbow has gone back a step while I heat treat the belly. I removed the handle block, not without some poor decision making in the process. (Note to self... use bandsaw not chisel!)
It had taken the merest hint of set over the middle of the bow (just 1/8" or so) so I clamped it down with about 1/8" of reflex mid bow just to pull out the set whilst heat treating it.

The main reason for removing the grip block was so that I could get the heat treating right in under the grip, but keeping it off the actual splice. I taped a thin off-cut of Yew over the glue area of the splice and carefully clamped slats of wood to the sides of the bow to keep the heat onto the belly and off the splice.
Anyhow, that was all done and a new thinner longer handle fade block glued on. That's nicely cured this morning, and I'll add another thin build up block for the grip today.
The result of all this messing about is the bow should be substantially stiffer in the centre section and have a more gentle fade from limb to handle. It should make the 50# at 28" that I wanted.
All a lot of work, but I've learnt some new stuff about heat treating backed bows and lateral correction. Someone has asked what glue I use to survive the heat treating... the whole point is you keep the heat away from the glue line... but for the record I use Resintite.
I've added the diagram to show how the side cheeks keep the heat off the glue line and back. The great thing about this set up is that the heat is directed along the channel formed by the side cheeks and gives a more even heat over a longer area, this also speeds up the proccess. You can feel the hot air blowing out at either end of the channel showing that it is going where you actually want it. (in the diagram, Orange is the belly, Yellow the backing and blue the side cheeks, these are clamped on with G clamps)

While I was in a gluing frame of mind I made a former for the RD Bamboo backed Yew flight bow.
It was sawn from 3/4" ply, done as two halves and screwed together with a couple of side cheeks at the join. Blimey what a struggle clamping and binding it to shape, a bit like wrestling a Python. I didn't go mad with the reflex and opted for gentle curves as I didn't want to risk fracturing the belly as it pulled into shape.
The Bamboo backing was taped onto the belly with masking tape to hold 'em together while I strapped it up (visible in the lower pic), a few temporary clamps were applied too.
I had to cut a whole load of extra rubber strapping and I was tired out by the time I'd got it all done, I was also dying for a pee, hungry and wanted to blow my nose.
Once I'd seen to those minor distractions I thought I'll take a pic for the blog... Good call.

It really shows the value of the blog as, while taking the pic I noticed the alignment was all to hell!
The former is rather long and only of 3/4" ply so it has little resistance to sideways bend or twist. The force applied to the rubber strapping had put in about 1/2" of sideways misalignment and a bit of twist.
The glue has a good long pot life of a couple of hours, so it wasn't a problem to fix a clamp to the bench and to pull one end across and into line. A sash cramp at the other end was supported and blocked up to take out the twist.
Whew, what a relief... if I hadn't spotted that, I'd have been struggling to re-align and de-twist the bow.


Thursday, 19 February 2015

First Flexing

The pic and video show it flexing to 28" at about 45#, nearly finished.
Hopefully I'll get the draw weight up to 50~ and tweak the tiller to get it a bit prettier.
Here's the story of how it got there.. it was a bit of a struggle!

I glued on some temporary nocks, adjusted my string to give a low brace height and tried to string it.
I could feel there was decent poundage there, but also the bow was trying to flex sideways, groan...
Lateral instability can be a problem with longbows or bows with thin tips. It's not helped by the way I tend to rough 'em out square e.g near the tips the bow is as wide as it is thick so it doesn't really have a preferred natural direction of flex.
I took the string off without letting it go sideways and took a good bit of wood off the corners where belly meets the sides, this removes a little poundage but makes it more inclined to flex towards the belly. It also gives the rounded belly expected on a longbow.
The irony is that at a high brace the bow is forced to bend the right way, or on a long string it is being pulled the right way. It's at a low brace it is most likely to try and flip sideways.

I increased the brace height and it was flexing ok but still trying to go slightly sideways. The upper limb also seemed much stiffer than the lower for no obvious reason.... damn!
Hmmm, all a bit stressful, but fortunately I have a host of tricks and techniques learned over the years which are applied one at a time to slowly remedy things.

Moving the nocks across by rasping away one side at the tip helped improve the string line but the bow was still biased a little to one side. I clamped it up with a slight sideways bend to compensate and heated the belly a little. This worked in getting it drawing nice and straight.
The stiff upper limb is probably due to some knotty areas in the Yew wood belly which tend to stiffen it. Rasping a little extra off got it nicely balanced... Whew!
But now the bad news... groan... the draw weight is lower than I wanted, it's about 40# rather than the 50# I want. Mind a little below 50# will probably be ok if it's a good fast bow, after all it's performance that matters not brute poundage.
Still, no need for panic, there are still a few trick remaining!

I always make bows a couple of inches longer than I really want and cutting an inch off each limb will give me another couple of pounds. This has been done and the video taken... the still is a frame from the video.
I can also heat treat the belly a tad (maybe just on the lower limb).
Heat treating will need doing with great care to avoid heating the glue line of the backing. I have a technique for this where I clamp thin slats of wood to the sides of the bow, this confines the heat along the belly and protects the back. This can give another few extra pounds an stiffen up a couple af areas that are flexing too much.





Monday, 16 February 2015

More Work on the Bamboo Backed Yew



The rubber strapping has been taken off, the stave marked up and run through the bandsaw.
I'd glued it all up a bit oversize to allow for any misalignment in the splice of the bamboo backing.
It would be a mistake to have it all cut too precisely before glue up.

It's held some reflex which looks a bit uneven in the pic, mainly because the bow isn't fully shaped... trust me it will look great eventually!

I haven't done the temporary nocks or started to flex it much yet. I did flex it a little with one end supported on the floor, it feels like I should have enough poundage, but these things can be deceptive.

I've glued a piece of Yew onto the belly over the splice, where the grip will be. It's about 6.5" x 1/2" just to bulk it up a bit for the grip . It also hides the splice and will slightly stiffen the very centre. I'm going for a fairly rounded (full compass) tiller, as although it's a target bow, the guy has a good long draw and it's nice to build in some extra.

The glue is usually left overnight, but I've had the glued riser block curing above one of my bench lights all morning. The clamps are off now and it's indoors in the warm. I may get the temporary nocks on it this evening, but I won't flex it in earnest until tomorrow.

You can see in the right pic which shows the reflex, there is a dark knotty discoloured area in the Yew at the tip (nearest the camera). This knotty area is a bit stiff, but the tips of a bow don't flex much as there is little leverage there. It should become a nice decorative feature when the tips are slimmed down and it's all polished.

As I was coming out of the garage I noticed one of my winter visitors waking up for spring! The Peacock butterfly wandered about on the doorstep rather sleepily, but then the weather went chilly again and it went back in!

Sunday, 15 February 2015

Boo backed Yew Glued up

I've been busy, the bamboo backed Yew is glued up and strapped into a little reflex while the glue cures.
It will be ready to have some temporary nocks glued on and be tried on the tiller tomorrow. I hope it has enough draw weight to play with.
It won't have all that reflex when it it's taken off the former, and by the time it's tillered there just be the merest hint. More pics tomorrow.


I've also got my next try for a flight bow ready for it's bamboo backing. I've spliced a couple of Yew billets together with some deflex and heated a little reflex into the limbs. When the bamboo back is glued on I'll pull it into a fairly strong deflex reflex shape. The billets are pretty thin so I think it will withstand a good bend and a fair bit of reflex... time will tell.
 This flight bow will have a minimal grip and maybe no arrow shelf, I may be able to shoot it as a "primitive" in NFAS field shoots, not sure I'll have to consider the rules... is it based on any recognisable primitive bow style???? I dunno lets see what it looks like when it's done. I wouldn't mind shooting a lighter bow for a while as I've got a niggle between my shoulder blades. Picked it up on the last field shoot, I got cold when we stopped for lunch and pulled something when we re-started. We'd been hanging around waiting as there was a queue on the first after lunch target. Don't need any of that 'warming up' stuff when you are 18, but these days, I need to think about what I'm doing.

Thursday, 12 February 2015

Starting on Bamboo Backed Yew 50#

A chap visited a while back and wanted me to make him a Bamboo Backed 50# longbow.
I'd sorted through my Yew and came up with a few heart wood billets. I sorted out the best two (the lower ones in the pic with 4 of 'em) One needed a little steaming to get it a bit straighter at the thick end where the splice will be. While I was steaming that one I also straightened one of the really waggly ones.

I taped the billets together as pairs and cut a Z splice using the bandsaw.
This post shows how both sides of the splice are cut together and it fits together as if by magic!
http://bowyersdiary.blogspot.co.uk/2014/08/good-days-work.html

A bit of fiddling and fettling to get a good fit and I've got the good pair glued up.
The second pair will be glued up with a big deflex at the splice (I'm gluing on exta blocks of Yew to allow then to splice togethe rat an angle (pics later when I do more). I'm hoping to make a 35# reflex/deflex flight bow (sound familiar?) it will be interesting to see how Bamboo backed yew compares with the Hazel.
I'll be applying some of the lessons I've learned from the Hazel flight bow. This bow will be more of a primitive, no arrow shelf or cutaway for the arrow pass. Longer working limbs and tons of reflex. I really really want this sucker to break 200 fps .

While the glue is curing I'm reducing the Hazel warbow some more. It's twisted to hell, but I can either a) ignore it, or b) maybe take a bit of twist out when I bend in some deflex/reflex.

I've put it on the tiller with a long string (hemp rope) and pulled it to 100#. The middle if flexing a whisker now, so it's probably about ready to try and steam in some deflex at the grip. Ironically the stave has near perfect deflex/reflex, but back to front!
E.g it's reflexed in the middle and tips are deflexed.

Just to put my mark in the sand I'm aiming for 90-95# at 31" deflex/reflex heat treated belly to be used as a clout/roving/flight warbow.
I don't give a tinker's cuss if it doesn't meet various 'definitions' of Warbow. I feel I can safely state that nothing I do to a bow won't have been tried by medieval bowyers already... ok the tools may be different, but I'm sure their skills and knowledge will vastly outstrip mine.

As an asside, for anyone who thinks I'm 'anti' the various societies... that's not strictly the case.
The Welsh Warbow Society seems an admirable organisation, having open shoots with no membership fee and a healthy all inclusive set of rules. Some of their articles are very informative too. Were their shoots closer, I'd doubtless get along to one... maybe I will this year, who knows what's in store for us?


Tuesday, 10 February 2015

Reworked Hazel Flight Bow

It's now more like a genuine 35# at 28", but I don't think it's made much difference, except maybe for the first shot. After that the bow had taken a little set.
I think I'm at the limit of the Hazel for that design... Maybe 3" extra limb length on each limb would help. I modelled it on the little Hazel 30# bow, but it has the lower limb about 30" and the upper 27"... by the well known law I happened to take the shorter limb.
Here are the speed figures:-
207.1fps
185.5
183.1
189.0
185.4
Out of interest the arrow with the 70gn point made 156.4fps.
I shall have another try for distance on a warmer day when the opportunity presents itself.

Sunday, 8 February 2015

Hazel Try Out

I tried the Hazel for distance, it was a tad disappointing, but I think the mistakes in the bow are showing up.
It made 193 yards but should probably have gone much further with the speed figures I'd obtained.
I only tried a couple of shots and didn't get a very good loose, it was also rather windy... but that's not the main thing.
I'd been miss measuring draw weight and length. I should measure draw length to the point where the point of the arrow would fall off the shelf and onto my hand. Now that is further than I'd normally draw as with a longbow you draw to the back of the bow, with the flight bow shaped grip, it's actually right up to the belly side of the grip. (My tiller rig rule was adjusted to suit longbows)

Anyhow, the upshot is the bow was actually drawing about 40# at 28" and putting more strain on the limbs than the Hazel bow I'd modelled it on. The result was there was virtually no string tension at brace. Maybe the 190 odd fps I got through the chrono was actually putting set into the bow.
So... I've taken some off the belly using the belt sander. It's V easy as the bow is tillered already and the belly is dead flat. I've got it to about 32# at 28". I can now try and heat treat/bend some of the reflex back into it.
This experiment will be fairly quick to do and I'm hoping that by taking off weight I'll actually end up with a faster bow. I've also narrowed the tips more, loosing some physical weight.

You can see I've done one limb. I took more care jigging it up for heat treating, made sure it got plenty of heat and took the tip right down to the end of the former, to give more bend,. Hopefully some of the reflex will stay in. In the first pic you can just see the limb is much darker just it is heat treated near where it meets the grip.

The good news is the laser rangefinder was V good. I took a sheet of thin steel plate (from the back of an old electric cooker) and propped it up on the shooting line. I could then sight back to it from the arrow and get a good consistent reading.
One of the guys on Primitive Archer suggested I should be getting nearer 250yards with that arrow speed.
So, game on, I'll see what I can achieve. It's all a good learning exercise.

Friday, 6 February 2015

Some Results

The bow feels pretty good and shooting off a shelf is easy.
I measured a force draw curve for the bow and it's now 35# at 27".
I find it's easiest to measure it by pulling to a know poundage and measuring the distance rather than pulling a fixed distance and measuring the poundage. It's done one reading at a time, letting the bow down after each reading.
(I went from 10# to 35# in 5# steps.)

I took a couple of my old arrows with missing points, cut them down a whisker and stuck on new ones giving a 27" arrow with a 70gn point.
Now to be fair, I'm not fully 'au fait' with the detailed conventions of flight shooting... where on the shelf and the arrow do you measure the draw to? Anyhow lets just press on... here's the force draw curve, which led me to ponder...
If the bow has zero poundage at zero draw (e.g zero draw at brace), and 35# at 27", assuming a linear force draw curve (and they generally are fairly linear) then surely there is only one possible line that joins those two points? I s'pose the bow with a load of stored energy at brace no longer has a straight line FD curve but has it bulging upwards in the early stages.
Now this bow doesn't actually have much (if any) reflex. That is to say the limbs have some reflex curve but, unstrung, the tips are not reflexed past the grip. In fact it's effectively got 1.5" of set.
So what if I thin the limbs to weaken them and remove some of the stress, I could then presumably get some reflex back into them and end up back at 35# at 27"... but would that be good, bad or what? Whaaa my brain hurts.... maybe I can actually try it once I've had some fun from the bow.

Right... shooting it through the chrono. I tied a nocking point to the string to give a consistent arrow position, but it was a tad tight on the nock. My first two shots were a bit tentative too.
151 fps
152,4 fps   Not bad, but not spectacular
next shot I made sure I used nearly the full length of the arrow shelf with a slash loose. That is pulling the hand back rather than letting the fingers creep forward as they are extended which can easily loose over 1" of draw.
172.2fps WOW!
I noticed the extra thread I'd whipped round the nocking point had come off and the arrow was now sitting loose on the string. Two more shots to check it wasn't a miss read of the chrono.
164.6fps
164.5fps
It was noticeable that the readings were vastly more reproducible with a near centre shot bow rather than a longbow where the arrow is snaking as it leaves the bow.
I'm very pleased with that. Hopefully on Sunday I'll try it for distance, and also try out my laser range finder.

Update:- 
I refurbished a flight arrow with a missing point, it's 252.3gn and I got 196.1 fps out of it.
I should point out the arrow is 28" long, but I don't think I took it to a full 28... mind I'm tempted to just to get past the 200 fps mark.

Thursday, 5 February 2015

Hazel Flight Bow Nearly There

It's a tad disappointing insofar as it's lost a fair bit of reflex, but the limbs are moving nicely and it's about 35# at 25"

I'll have to compare the limb movement with the original bow. I suspect the working limb length is shorter, and maybe the rapid seasoning of the wood hasn't helped. Hmmm that smacks of getting my excuses in early! It doesn't take much effort to string it, but the real test will be speed through the chrono.

The full draw pic may be a little deceptive. Due to the shape of the grip the bow isn't free to rock on it's support, however it looks like the mid limb on the upper (right) limb may need easing off a tad. That should get me the last inch of draw to 35# at 26". The brace height need to come up a whisker too. Pic on the right shows the string line.

I've prettied up the riser and it looks rather handsome even it it's rough rasped state. Maybe if the bow is a flop I'll carefully cut the limbs out of the riser and re-use it.
Here are some pics and video. Next step, make a string and test shoot it. The limb tips need narrowing too, but it will be fun to get a shot out of it.

Woo hoo. Just tried some first shots.
I had to do a kissy kissy target archer style draw, but it seemed to ping 'em down range rather nicely. of course the chrono will tell the real story, but that's for another day when I've got some cut down arrows to avoid overdrawing it.
I also want to re-weight the original Hazel bow to see if I can get a fair comparison.

Monday, 2 February 2015

Flight Bow Riser

Bearing in mind I had no idea what I was doing, I asked that nice Mr Google about riser dimensions, limb angles and such like. It turned out I pretty much had the limbs angled back same as a modern olympic recurve riser.
The limbs will sort of scarf/dovetail into the riser and be glued in, I'm not making it a take down as that would have metal bolts and stuff which would seem odd with Hazel limbs.
The riser is from a couple of bits of  "mahogany" (I put inverted commas as Mahogany has sort of become a generic name for all sorts of random tropical hardwood). I was given a huge length of the stuff about 12' x 3' x 1" by the guy next door who was reluctantly throwing it out when his garage was getting turned into a dining room. (The things we men do to keep our other halves happy! ).
The sight window is much shorter than on a target bow, as a) It's for flight and b) If I use it for field I'll be canting the bow at an angle so I won't need a huge cutaway to let me see the target.
The Hazel limbs have been back on the former and had their bellies lightly heat treated and the reflex restored as some of the curve had pulled out during the tillering. Because of that, I have slightly increased the deflex angle of the limb mounting. E.G they are angled towards the archer a little more. This is mainly a precaution to hopefully ensure I end up with a working bow. It may not end up bing very reflexed, but I hope it will be a useful reference for future bows.

Mean while I got chatting to a bloke on one of the archery forums who was thinking of going from recurve (barebow) to longbow. He didn't live too far from me and came over to try a few bows to see what poundage suited him. He shot all my longbows including the 70# at 28" but felt 50# was probably about right.
I'll make him a bow and I can always take 5# off it if he wants once he's had a good go with it. I've already started looking out suitable Yew heartwood billets for a bamboo backed Yew bow for him. I've got 5 sorted out and I'll pick the best matched pair with enough thickness to get 50# (I'll judge that from my existing boo backed Yew bows with a bit of guess work thrown in)

He had a go with my only bow that will take a 32" draw and got it to about 30". He hadn't been shooting that long but seemed to have a nice smooth easy action. He wasn't used to shooting at such short range and took a while to zone in. We had a go with the Chinese repeater and my all wood crossbow too, it's always fun.
What I really liked is the way he asked what days were good to visit and when I told him, he suggested "Is tomorrow too soon?" Brilliant! I like action rather than endless dithering. A lot of people threaten to visit, or say they want bows and then the communication fizzles out ...
I've learned to shrug, but personally, if I want something I'd rather get stuck in and get it started.

Many many years ago a primary school teacher said I was "neck or nothing"... meaning I'd go all out to the point of risking my neck or I wasn't interested at all. It amuses me that he could see that in me at about 10years old.

Stiff Limb Mystery:-
In going through my billets I found a skinny scrap of Hazel which would make a stick bow. I ran it through the band saw and set to with draw knife and spokeshave to make a quick fun bow. One limb was far too stiff despite being about the same thickness or slimmer than the other. There was a thin dark streak on the belly and a corresponding small bulge/knot on the back at mid limb. It was this spot that seemed stiff. As I carefully reduced the belly, it started buckle at the dark streak, I picked away at it with a tiny chisel and splinter/strip of wood about 2" x 1/4" and about 1/16" thick lifted revealing a black shiny surface that looked almost like rust. Of course once this layer was removed the limb became weak as hell with a huge hinge at that point. I gave it a damn good bend, but it didn't want to break. Maybe I'll patch it for the heck of it. It just goes to show that internal features that you can't see can make a huge difference, and the physical dimensions don't always relate to the amount of bend.