Primitive Archer
Main Discussion Area => Bows => Topic started by: Allyn T on July 15, 2021, 09:05:26 am
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If I wanted to make an elb what criteria do I have to follow? I know it's 5/8 thickness/width minimum but I just read that the top limb is longer, does it have to be? This would be a hunting weight bow not a warbow.
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Most of the rules are nonsense and there are slight variation between different societies.
There is no rule about where the grip is... it's normally fairly central with arrow pass 1" above centre, but there is no specific rule. Some societies insist on horn nocks, but they don't even understand the difference between horn and antler ::)
The 5/8 rule isn't really a problem as they usually come out well within that limit.
Don't worry about rounding the belly too much, It doesn't need to be semicircular in cross section.
Generally it should be one single curve when braced (e.g. No obvious recurve)
Del
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I think Del summed it up quite well and that's coming right from the cat's meouth. ;)
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Awesome thanks Del : )
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oooh, one other thing.
No part of the bow should be wider than the grip/arrow pass. e.g no cutaway for the arrow.
But again that is slightly daft, as if a natural stave has a big knot then the limb may need to be wider ther and could feasibly be wider than the grip/arrowpass.
The problem is the rules weren't written by bowyers.
I mean... if a stave has natural reflex etc... it would be allowed... but can they really tel the difference between steamed in and natural? :o
Del
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Make sure you tiller it elliptically or else handshock awaits :) Get it right and the bow will be quiet and very nice to shoot. Tiller is key.
If you use a gizmo, make the bend increase as you progress along the limbs. Virtually no bend in the handle.
My width profile for ipe bellied elb's is as follows - 1" wide through the grip (grip 4", 1" above center 3" below) and 4" either side. From there taper into 3/4" wide 8" from the nocks, from there taper to 3/8" at the nocks. This works for bows in the 45 - 80# range. That sort of a taper will work well. Adjust widths for different woods.
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Here are the rules to making an English Longbow
Step 1: make an English Longbow
Step 2: WRONG!
Step 3: Get bashed by experts on the internet
Step 4: Shoot your bow and enjoy it
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Here are the rules to making an English Longbow
Step 1: make an English Longbow
Step 2: WRONG!
Step 3: Get bashed by experts on the internet
Step 4: Shoot your bow and enjoy it
Lol I think I can follow those rules. Bownarrra thanks for the starter dimensions
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I thought bownarrow gave you sound advice. Especially on the tiller. A circular tiller on those longbows can have horrible shock. The 5/8 rule we have to adhere to in flight shooting.
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Personally I don't know where all the "circular tiller gives you hand shock comes from" :(
Maybe what I call arc of a circle tiller isn't what others call circular.
The only hand shock I've ever had from a longbow was from a heavy hazel warbow that was very wide in the grip and an uncomfortable shape which sat poorly on the knuckles. I have made quite a few ;D
Maybe what follows is one explanation for hand shock?
I have seen suggested layouts like this:-
a) Straight grip section (say 6") and then taper the thickness from there.
That is so wrong on many levels, as it is actually making the grip weak!
b) Thickest part is actually at the centre, tapering from there.
That makes the grip stiffer than in "a".
c) Lower weight bows often have the grip thicker for comfort, often achieved by gluing a short riser section, this obviously gives a stiffer grip, gives a more elliptical look (regardless of the actual curve on the limbs) and help stop any hand shock.
Del
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a) Straight grip section (say 6") and then taper the thickness from there.
That is so wrong on many levels, as it is actually making the grip weak!
b) Thickest part is actually at the centre, tapering from there.
That makes the grip stiffer than in "a".
Del
Del I don't quite understand what you are saying here. Also do you wait to add horn nocks till after you have it tillered somewhat?
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I've done a sketch that hopefully shows what I mean... It shows the thickness taper at the grip (exagerated), you can see, when it is tapered from the centre there is more thickness in the grip (shaded area) compared with when the taper starts at the ends of the grip.
Regarding horn nocks, leave it until the bow is braced and drawing say 20". Before that it's best to keep the outers a bit wide, so that any sideways adjustment of string line can be done to avoid the bow trying to bend sideways, which longbows can tend to do. That's also a good reason to keep the limb cross section rather rectangular until the bow if flexing nicely, rounding the edges where belly meets side can be useful for counteracting sideways bend.
Hope that makes sense
Del
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Ah I understand now, thank you del
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I made a 70 inch Elm long bow that I even fire hardened. Still has 1 inch string follow. Flat back with rounded belly but the riser has 3 inch fades, and an arrow shelf cut in to it. Hybrid I guess , but is fun to shoot at 45 lbs of draw. Just can't get myself to shoot off of my knuckle, so I still haven't built a true ELB to date.
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Del, I've always believed the same... stopping the thickness taper to create an area mid bow that's all the same thickness makes it weaker, not stronger. If you want to make it stronger there, increase the taper rate, don't eliminate it.
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I agree with Del’s point but often the grip is left so thick that the extra strain at the center doesn’t really matter. It also detracts from the aesthetic look of an ELB when there’s a noticeably raised handle section, though I am aware that many bows over time have been made in that fashion.
As far as hand shock, it makes sense that a circular tiller could result in hand shock with excessive outer limb mass if designed that way. Bownarra’s design sounds quite wide in the outer limbs to me for starting at only 1” wide in the center and 3/4” 8” from the tips. For a 68” long bow that would be a taper of 1/4” over 24”. If that were a straight taper it would result in nocks over 5/8” wide. A pyramid taper to 3/8” nocks would put the 3/4” width before mid limb. Those are pretty drastic differences in where that width is placed. He of course recommended an elliptical tiller which would move that mass more efficiently than the circular tiller.
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re Bowanarra's elb limb width design: I came up independently through trial and error with virtually exactly the same layout limb (15/16"). I prefer it because the extra width 8" from the tips greatly reduces the tendency to twist sideways, which is common when using tropical hardwoods, with elb's.
Not saying a pyramid taper doesn't work, but you will lessen your chance of issues.
I laugh when I think about tillering really narrow longbows ie 3/4" wide. No matter how I lay the limbs out, as often as not when first stringing the bow They usually want to bend sideways, so you have to slowly train it to bend in the desired conventional way.
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Makes a lot of sense to design the bow that way. Particularly with those woods. The problem I see with the layout comes when people tiller it to a circular shape or worse, with too much bend in the inner limbs/stiff outer limbs as we so often see.
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Add horn nocks when the bow is at about 24"
My width taper works very well. I haven't had an elb bend sideways in a long time. I made a perfect template out of a 0.050" glass strip this eliminates any layout issues. Side bend is normally width layout/centerline off, or reduction of the limbs unevenly. Or of course a less than optimal straight width taper, they aren't the best idea (if you went that route though the tiller would need to be a little more circular...but only a little!)).
I taper from the edge of the grip - remember unless you are aiming for a bow cut out at dimension you will be removing a fair bit of material from the limbs anyway so the handle won't bend too much. I never have that problem, it is more to do with the thickness there than where you start the taper.
Del you may not know where the circular tiller handshock thing comes from but it ain't no fantasy :) Not trying to get into a pissing match but I too have made a few :) Somewhere around 300 elbs now, I'd like to think I know what i'm talking about by now haha ;) Things that many of my customers have said about my bows confirm that I must be on the right path - its not just my ego talking.
Like most things bow making....many ways to skin the cat......but by definition one way is optimal :)
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I think maybe there is some misunderstanding...
My suggestion to leave the tips wide until later in the build (say the point when nocks are added) is just a wise precaution for anyone not used to making ELBs or anyone using a stave, it's not a criticism of any suggested profile.
Obviously the risk of the bow bending sideways are less when using laminates, in which case cutting out to a template is fine.
Regarding thickness taper at the grip, I would imagine (and please correct me if I'm wrong) that if using tapered core laminations they would meet near the centre, with the back and belly either being parallel or again tapered from the near centre? However I expect many laminated bows have a riser section which will give a stiffer grip.
Arc of a circle tiller doesn't IMO mean a weak grip with too much bend there, it can include a stiff grip or riser with each limb being arc of a circle, (the circles being centred at the extremities of the grip rather than the centre of the bow).
I can only say what I've found to cause hand shock and that has been a poorly shaped grip, presumably those who say it's due to circular tiller have made or shot bows with hand shock or have shot poorly made bows and attributed the shock to "circular" tiller rather than simply "bad" tiller. If you can see the bend at the grip then it's probably bad tiller eg, like a bit of 1x1" with no taper at all.
Del
PS. I have no interest in "pissing contests" as, at my age I would doubtless lose!