Primitive Archer
Main Discussion Area => Bows => Topic started by: mmattockx on March 03, 2020, 09:31:16 pm
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So, I'm at the tillering stage on my maple board Mollegabet style bow. First one ever for me and I am trying to go super deliberate and not screw it up. 68" NTN, target weight is 30lb @ 28". I currently have it drawing 30lb at 5" or so on a long string at and spent well over an hour this afternoon slowly scraping my way to that point. Slow work!
The tillering tree is dead vertical and the bow is level at the start, the shelves are not true. Tell me what you all see:
(https://i.imgur.com/Dxo0pNW.jpg)
(https://i.imgur.com/0V4Vf98.jpg)
So, do I just keep taking wood off and reducing weight until I get a few more inches of draw then low brace it and keep going from there with a real string or something else?
Thanks,
Mark
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Hi Mark,
deliberate is good! nice looking workmanship in the lam job, A pic of the back would help others get an overall view.
Before anyone offers an opinion, I would like to ask you what you see! where does the bow appear to bend the most in the second pic? The acquired skill of tillering is all about judging bend.
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I don't have a good pic of the back, this is the best one while the tip overlays are being glued on. After this picture I backed the board with fabric from an old bed sheet and Titebond III.
(https://i.imgur.com/C9kxM7D.jpg)
What I see on the right limb is it is a bit stiff out of the fade, then maybe a slight hinge a few inches up and then stiff towards the end of the working limb. On the left limb it looks weak out of the fade, then stiff in the mid portion of the limb and the end bending not too badly.
Mark
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Hi Mark,
I'm seeing the most bend right above the florescent tube ends peeking out of the box behind. as for the right limb being a bit stiff outof the fade, I dunno, but I am just looking at a single pic and you have the advantage of looking at it from all angles and as you pull. Personally, I would concentrate on getting the mid limbs bending evenly, and hold off on revisiting the fades for a while.
Do you intend to have the tips bend slightly?
One thing I like to do is have a good idea what the design (in a well tillered example) looks like at brace. Luckily there are lots of nice examples to view here at PA, and then try to get my bow looking similar before I draw it further than that with the long string.
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Not really enough bend to see much (it's mostly at the fade as the others have stated), but what strikes me is that the bending portion of the limb (between grip and lever) appears to be thicker at the lever end (could just be an optical illusion where the camera can see a hint of belly as well as the edge)
I'd measure the thickness of those sections every 2 or 3 inches and check that you have some thickness taper.
Alternatively, nip up some verniers at the end nearest the fade and slide them towards the tip, you should be able to see an increasing gap opening up as you slide along. I'd suggest you should have at least 1mm of taper every 6".
Where you have a stiff lever and a short working limb, you have to get the working limb bending very evenly.
Del
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Personally, I would concentrate on getting the mid limbs bending evenly, and hold off on revisiting the fades for a while.
Do you intend to have the tips bend slightly?
I will keep at the mid limbs, they are certainly stiff on both sides. I was expecting the levers to be stiff with no significant flex.
One thing I like to do is have a good idea what the design (in a well tillered example) looks like at brace. Luckily there are lots of nice examples to view here at PA, and then try to get my bow looking similar before I draw it further than that with the long string.
Yes, all I am trying to do is get to brace height with the long string and decent tiller.
Not really enough bend to see much (it's mostly at the fade as the others have stated), but what strikes me is that the bending portion of the limb (between grip and lever) appears to be thicker at the lever end (could just be an optical illusion where the camera can see a hint of belly as well as the edge)
I'd measure the thickness of those sections every 2 or 3 inches and check that you have some thickness taper.
Alternatively, nip up some verniers at the end nearest the fade and slide them towards the tip, you should be able to see an increasing gap opening up as you slide along. I'd suggest you should have at least 1mm of taper every 6".
Where you have a stiff lever and a short working limb, you have to get the working limb bending very evenly.
Del
They started at the same thickness from fade to lever. I have been taking most of the scraping off towards the levers to get that taper started, but it is nowhere near the 1mm/6" you mention. I will run a set of calipers over it and see what I have now and keep working towards more taper.
Thanks for the input,
Mark
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Just in the interests of accuracy (as I was sort of guessing :-[ ) I've been and checked my Molle flight bow.
The working limb is about 13" long... measuring at 6" intervals I got varied results due to the natural Yew sapwood back, sometimes less than 1mm sometimes more. So I took measurements over 12" and it was 2.24mm. So 1mm per 6" seems a reasonable start point.
The bow can be seen at full draw here:-
BTW it eventually after a little re-work shot 283 yards, not bad for a 45# bow :)
https://bowyersdiary.blogspot.com/2015/07/whew.html (https://bowyersdiary.blogspot.com/2015/07/whew.html)
Del
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Hi Mark,
a few thoughts, and of course a question. is the handle area width (as seen from the back) close to finish width? The pic of the bow on the table shows a rather wide handle.
do I just keep taking wood off and reducing weight until I get a few more inches of draw then low brace it
yes a few more inches until it bends on the longstring to about what would be brace height were it braced to take a long hard look at it, but I would actually wait until the bow is reduced further to try to brace it for the first time. 30#@ what would be 20" - 22" if you are shooting for 28" finish draw length.
see http://www.primitivearcher.com/smf/index.php/topic,65722.50.html (http://www.primitivearcher.com/smf/index.php/topic,65722.50.html)
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The working limb is about 13" long... measuring at 6" intervals I got varied results due to the natural Yew sapwood back, sometimes less than 1mm sometimes more. So I took measurements over 12" and it was 2.24mm. So 1mm per 6" seems a reasonable start point.
My working limb is longer at 18", with a 12" lever. I will keep at the scraping and working to introduce more taper and see how it works out. I will leave the fades alone completely until I get the mid limbs working more. Once I get there I will post a new picture and get more commentary on it.
a few thoughts, and of course a question. is the handle area width (as seen from the back) close to finish width? The pic of the bow on the table shows a rather wide handle.
The handle has not been worked on yet and is the same 1.5" width as the rest of the working limbs. Since it's to be a stiff handle I figured it wouldn't make any difference to the tillering and this way I can pick which limb is top after seeing how they are bending. I can certainly rough it to finished width before continuing if that matters.
yes a few more inches until it bends on the longstring to about what would be brace height were it braced to take a long hard look at it, but I would actually wait until the bow is reduced further to try to brace it for the first time. 30#@ what would be 20" - 22" if you are shooting for 28" finish draw length.
Ok, I can do that with no problems.
EDIT - Willie, I just got through reading that thread you linked to on measuring draw weight with a slack long string. That is super useful, many thanks.
Mark
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I can certainly rough it to finished width before continuing if that matters.
I am not sure if it matters, I might could be done either way, but my own order of operation is to get the fade area to desired depth and width, before tillering. I also take care to make sure that the full limb width (as seen from the back) extends a half inch extra towards the center of the bow from the point where the working thickness of the limb begins. Preventing excessive bending out of the fades is the reason for the precaution.
Many like to leave the fade area a little stiff until later in the tillering process, and get it bending more, if and when, set starts to show as you get close to full draw.
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Floor tiller!!!.
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I am not sure if it matters, I might could be done either way, but my own order of operation is to get the fade area to desired depth and width, before tillering.
Because the wood is only 1.5" wide I am not taking very much off handle portion in the fades. The overlap of full width from the fade into the working limb is a bit over an inch, so I am well covered there.
Many like to leave the fade area a little stiff until later in the tillering process, and get it bending more, if and when, set starts to show as you get close to full draw.
I can understand that after some experience with how tillering goes. I spent a while scraping again today and gained another couple inches of draw at 30lb. Up to a bit less than 17" at this point, with at least another 3" to go before bracing it. Things sure move slowly, I now have close to 0.080" of taper on the limbs and they are just beginning to bend a bit and there is a large pile of shavings under my bench. It will be much larger before this thing is bending as it should.
Mark
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Things sure move slowly
yes it seems that way on the first bow, however things move very fast when taking those last few scrapes as you near full draw. But of course your deliberate progress will pay off at the end. :)
Bet the guys would like to see a pic at 17"or 20". More pics = more response here at PA
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yes it seems that way on the first bow, however things move very fast when taking those last few scrapes as you near full draw. :)
I expect so. What's killing me is having no experience to know when I'm getting close. I could have rasped off a bunch of this wood but without a feel for the progress I am sure I would just overshoot and end up with a 12lb bow.
Bet the guys would like to see a pic at 17"or 20". More pics = more response here at PA
(lol)
Fair enough, today's progress shown at 17" draw length:
(https://i.imgur.com/RAPQexh.jpg)
Mark
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I guess 17" draw all depends on how much droop you keep in your longstring. This recent thread demonstrates a use for an elastic cord for judging tiller shape, but I use the same method to also see how far the tips are coming back. I like to see the tips come back 10" or so which would correspond to about a 20" draw with a braced bow, before I brace it for the first time. As for how long a longstring should droop, there are about as many preferences as there is bowyers. Many start with 5"-6" droop and shorten it to slightly slack with no droop as they get closer to the point they decide to first brace.
http://www.primitivearcher.com/smf/index.php/topic,67369.0.html (http://www.primitivearcher.com/smf/index.php/topic,67369.0.html)
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slow is good :)
Del
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If you drew a straight line between you nocks you would see you are at about a 4" draw or low brace. Until you get off the tillering string and brace the bow you won't have a clear indication of how much you are drawing the bow.
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Many start with 5"-6" droop and shorten it to slightly slack with no droop as they get closer to the point they decide to first brace.
I had about 7" of droop before that picture was taken. I don't have a tillering string yet and am using a piece of paracord, so it is stretchier than a string would be. The limbs are flexing about 5" in that last picture.
slow is good :)
Del
It is, but it tests the patience.
Until you get off the tillering string and brace the bow you won't have a clear indication of how much you are drawing the bow.
I understand that, I was just referring to the thread that willie linked to a few replies back that showed you can estimate draw weight using a slack string.
Mark
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Some more work today. Bow is pulled to almost 21" on the slack string, so 4" farther than the last picture.
(https://i.imgur.com/Cjk7icv.jpg)
Mark
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Mark,
from what I see in the pic, the left limb needs to bend more nearer the handle, and the right limb more in the outer bend area.
you have actually chosen a challenging design for a first bow, as your working bend area is constrained by the nonworking tips, and you will have to make the most out of the shorter working length.
I use a short straight edge like a business card to slide along the limbs to judge the gap. (I use my cabinet scraper)
I also use large nicholsen pipeliner file as a fine rasp to speed reduction. rough with the rasp in the areas you see as straighter, then smooth with the cabinet scraper.
Fine rasp alternatives can also be a length of coarse beltsander belt, cut and mounted to a 1x2 to use as a rasp. the shinto rasp is another fine rasp, (and alls you really need is the replacement rasp part without the handles.) same technique, rough some then use the scraper to smooth again.
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Mark,
from what I see in the pic, the left limb needs to bend more nearer the handle, and the right limb more in the outer bend area.
you have actually chosen a challenging design for a first bow, as your working bend area is constrained by the nonworking tips, and you will have to make the most out of the shorter working length.
I use a short straight edge like a business card to slide along the limbs to judge the gap. (I use my cabinet scraper)
I also use large nicholsen pipeliner file as a fine rasp to speed reduction. rough with the rasp in the areas you see as straighter, then smooth with the cabinet scraper.
Fine rasp alternatives can also be a length of coarse beltsander belt, cut and mounted to a 1x2 to use as a rasp. the shinto rasp is another fine rasp, (and alls you really need is the replacement rasp part without the handles.) same technique, rough some then use the scraper to smooth again.
Thanks for the look. I do have a few large coarse files, never thought of them for roughing the limbs. I will have to pull one out next time I get out to the shop. I will also try the straightedge to get a good look. I intend to make a tillering gizmo but have been frozen out of my woodshop for the last couple days so that has been delayed. I am away for a few days for work, hopefully will be back in the woodshop when I return and get the gizmo made. It seems like I have enough bending going on that it is time to put it to use.
Mark
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forgot to mention, if you have clogging with the files, chalk or soapstone works wonders. I actually prefer files and rasps to sandpaper, as embedded grit makes for more scraper sharpening work
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fwiw ... no matter how this 1st bow turns out, you've done good.
Ya chose a maybe overly challenging design and employed patience so far. Have likely learned much along the way ... all of which can be used on next project.
Good luck!
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Totally agree with Knoll. Each and every bow you make will teach you something if you pay attention. Your patience will help you succeed. Once you make & properly use a gizmo the stiff spots will become obvious. You're off to a great start.
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forgot to mention, if you have clogging with the files, chalk or soapstone works wonders. I actually prefer files and rasps to sandpaper, as embedded grit makes for more scraper sharpening work
I will keep the soapstone tip in mind, I have plenty of it sitting around. Sandpaper just doesn't seem like the way to do something like this, it is clearly a fine woodworking project and decent hardwoods like the hand tools like the scraper.
FWIW, it feels like I am almost past the file/rasp point with my level of experience. The last couple scrapings made noticeable changes in the tiller and the length I am pulling to at the 30lb weight moved a fair bit. I think I am going to keep up with the scraping and try not to overshoot my target on this one and save the rasps for the next one when I know I have lots of wood left to remove.
fwiw ... no matter how this 1st bow turns out, you've done good.
Ya chose a maybe overly challenging design and employed patience so far. Have likely learned much along the way ... all of which can be used on next project.
Good luck!
Totally agree with Knoll. Each and every bow you make will teach you something if you pay attention. Your patience will help you succeed. Once you make & properly use a gizmo the stiff spots will become obvious. You're off to a great start.
Thanks for the kind words, gentlemen. I certainly have learned a bunch to this point and will do some things different on the next one. Speaking of the next one, is it bad that I am already making plans before I've finished this one?
Mark
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More pictures for the entertainment of those more experienced than I (which is everyone at this point...).
First, with no weight on the string. It has a little bit of slack that is not apparent due to the stretchy nature of the paracord. If someone wants to sell me a quality tillering string now would be a great time to make your pitch!
(https://i.imgur.com/3CnOJEI.jpg)
Pulled to 20" on the much less slack string, with a fair bit more bending. The tips are very close to brace height at this point and I won't go much further before I have a string in hand and can work from full brace. I am waiting on a string because local suppliers are out of stock, amazon doesn't have what I want and I'm not ready to learn how to make strings just yet. One thing at a time...
(https://i.imgur.com/EcaMc4R.jpg)
I find it very surprising how springy the limbs feel when it is drawn, it doesn't feel dead or sluggish at all. I also don't regret aiming for a 30lb draw weight to begin building strength and technique with. 30lb is going to be plenty challenging to hold at the start. Those who start with a 45+lb bow are kidding themselves if they think they aren't overbowed and learning bad habits with that much weight.
Mark
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Looks almost ready to brace.mind you I build bows a little different than most..
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I would get the left inner limb bending and go for it .right looks good so far.
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I would get the left inner limb bending...........right looks good so far.
I agree about the bend. Some bowyers make it a rule not to pull the bow any further until there are no spots bending more than any other spot on either limb.
Did you see the brace pic of bushboys recent moose bow? your limbs are similar in design so they should show a similar working limb profile. you can even do your adjustments without drawing as far as you already have.
btw, Nice bow, bushboy
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I agree about the bend. Some bowyers make it a rule not to pull the bow any further until there are no spots bending more than any other spot on either limb.
Did you see the brace pic of bushboys recent moose bow? your limbs are similar in design so they should show a similar working limb profile. you can even do your adjustments without drawing as far as you already have.
I will keep working on that inner limb until it is bending more and not take any more weight off until it is.
Is this the bow you are talking about?: http://www.primitivearcher.com/smf/index.php/topic,67285.0.html
I am finding the forum search function is beyond hopeless so I hope that is the one.
Mark
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Hi Mark,
I will keep working on that inner limb until it is bending more and not take any more weight off until it is.
Actually, if you pull your bow to a bend that is equivalent to say, a 6" brace height, and then remove wood in the stiff areas, you will be taking weight off. The scale will indicate less and less to obtain the same bend. Once all looks even at 6", then pull your bow till you see any unevenness or reach 30# again, which ever happens first. Hope you don't feel I am splittings hairs, but here is a good read on what Badger calls a "subtle distinction" http://www.primitivearcher.com/smf/index.php?topic=61452.0
An important step is to radius the edges of the back if you haven't done so already, board bows especially will want to raise a splinter with surprising little bend, (a slightly rounded belly is easier to scrape also)
Yes thats the bow, His has a slightly working tips, as the reflex he added straightens slightly at full draw. It is the inner limb profile that I thought was worth comparing.
simple machine forums are indeed simple, especially the search function. a google search of moose bushboy site:http://www.primitivearcher.com/smf/ works in spite of the fact that I didn't even get the thread title correct
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Actually, if you pull your bow to a bend that is equivalent to say, a 6" brace height, and then remove wood in the stiff areas, you will be taking weight off.
That is true. I should have been more specific and said I will not take any more wood off the limbs overall, just at the stiff spot.
A question - the left limb in the pictures is bending a bit more than the right when I use a straight edge to measure gap along the belly. Do I want to get the right limb bending more to match the left after I go to a regular string or just go by which limb looks stronger and work that one down?
An important step is to radius the edges of the back if you haven't done so already, board bows especially will want to raise a splinter with surprising little bend, (a slightly rounded belly is easier to scrape also)
Yes, I did that before doing any tillering at all. I am doing most of my scraping with an old pair of scissors that have a slightly radiused cutting edge that scrapes a relatively narrow line and then smoothing/flattening the belly with a straight edged scraper to finish. It is sort of the reverse of a rounded belly, but gives the same effect of easing the scraping work.
Should the edge/corner of the belly have much radius? I've been breaking the sharp edge with the scraper but not ever putting more than 1/32"-1/16" of chamfer on it. I figured I would round it slightly during finish sanding to match the back and be comfortable to handle.
Yes thats the bow, His has a slightly working tips, as the reflex he added straightens slightly at full draw. It is the inner limb profile that I thought was worth comparing.
Good. I will look at the pictures again as a guide.
simple machine forums are indeed simple, especially the search function. a google search of moose bushboy site:http://www.primitivearcher.com/smf/ works in spite of the fact that I didn't even get the thread title correct
I tried the google site search but got the site string wrong by leaving the stuff after the /smf/ on the address. I will make a note of that so I can use google in the future, it usually does a much better job than forum search engines.
Mark
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This one may be a better example...
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the left limb in the pictures is bending a bit more than the right when I use a straight edge to measure gap along the belly. Do I want to get the right limb bending more to match the left
yes, but concentrate on the left inner first and get the left as even looking as the right, even if the whole left limb bends more than the right while fixing that spot. you pretty much have your taper established on the right and getting it to bend more is a simple overall reduction.
Do I want to get the right limb bending more to match the left after I go to a regular string
I would do it on the long string before I pulled further, and would pull it further and keep it even before I brace. when you decide to brace, you might consider a course of action described by jeffp51, a low brace at first progressing to a full brace closer to the end. http://www.primitivearcher.com/smf/index.php/topic,67447.msg947680.html#msg947680
Should the edge/corner of the belly have much radius?
it doesn't need to like the back, what ever makes the scraping go easy or suits your design, a relatively flat belly design works well for most whitewoods.
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This one may be a better example...
Many thanks. That looks like a circular arc to me, is that right?
yes, but concentrate on the left inner first and get the left as even looking as the right, even if the whole left limb bends more than the right while fixing that spot.
Will do.
I would do it on the long string before I pulled further, and would pull it further and keep it even before I brace.
That lets me keep working while I track down a string so I will go that way. How much more draw before bracing it? I'm down to 20" with as tight a slack string as I can arrange for and don't want to go too far before bracing.
it doesn't need to like the back, what ever makes the scraping go easy or suits your design, a relatively flat belly design works well for most whitewoods.
A small radius it is then. The belly is dead flat and staying that way as it's the most structurally efficient cross section.
Mark
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That lets me keep working while I track down a string so I will go that way. How much more draw before bracing it? I'm down to 20" with as tight a slack string as I can arrange for and don't want to go too far before bracing.
as long as you are using parachute cord its going to be difficult to say. I would bring my tips down 10 " or so. Others get by with less, some prefer more. not sure you can go "too" far on the longstring with your design, as it's the tips that give a false read between long string and normal string.
I wouldn’t go much further than bringing the tips back 12" I guess. a half a dozen strands of cheap braided dacron fish line, like is used for fly-line backing or saltwater reels would be an effective temporary substitute for a bow string, and for making up a decent tillering string. 50# test might be available in your area.
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as long as you are using parachute cord its going to be difficult to say. I would bring my tips down 10 " or so. Others get by with less, some prefer more. not sure you can go "too" far on the longstring with your design, as it's the tips that give a false read between long string and normal string.
OK, 10" is a ways from where I am at now so that gives me room to work some more over the weekend. I was worried about the tips after reading that thread by DC but if the stiff levers eliminate that problem then I won't concern myself with it.
Mark
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Today's progress:
Pulled to 24" on the long string, tips at or past 10" of movement. Right limb looks stronger to me and the left limb has a slight twist, which is why the belly is showing more on that side. How do I deal with that?
(https://i.imgur.com/oao5AnG.jpg)
Low braced to ~4" (I couldn't wait after getting it moving nicely...)
(https://i.imgur.com/a6DVIYc.jpg)
Pulled to 17" draw from the low brace (Only pulled 20lb at that point). Right limb still looks stronger but I also had the string tight on the nock and it wasn't moving properly. I ran out of time to fix that, will sort it tomorrow and take a new picture.
(https://i.imgur.com/8GSEmBK.jpg)
I have found a bow string, should have it Monday or Tuesday next week. Do I brace it to full height and keep going on taking weight off while getting to my draw length target or something else?
Mark
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Looking nice , Mark, your deliberation is paying off as it's looking like a success on your first.
I wouldn't brace any more for now, as your 4 inches seems to be measured from a rather deep handle. This will do well until you finish it out. I agree the right looks stronger, and needs some more work. I wouldn't pull any further until you even it up. A solid backdrop behind your tiller tree would help the visuals. I would put up something rigid that you can see a tracing of your limb curve on as you go. a tiller stick will enable you to hold it at the point I see it in the last pic and make the tracing, a lot of folks don't care to use a stick, as it is not the best to keep a bow drawn for to long, but long enough to make a quick trace on the backercoard, then you can tack it up behind the tree. The idea is that you can flip the bow left and right to see differences easier.
another thing to keep in mind is that as you near full draw with your pulls being the desired finished draw weight, you might want to stop 2 inches short. by the time you have shot the bow in (a couple of hundred shots) at the reduced draw length, and finished sanding and any final radiusing, you might find a slight loss of draw weight or need to touch up the tiller somewhere.
twist: http://www.primitivearcher.com/smf/index.php/topic,27206.0.html
Does the thickness run off to one side where it is twisted, or do think the wood varies in the twist area? maybe softer
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Looking nice , Mark, your deliberation is paying off as it's looking like a success on your first.
I can't believe you said that out loud! That Murphy guy is everywhere, you know. :o
I wouldn't brace any more for now, as your 4 inches seems to be measured from a rather deep handle. This will do well until you finish it out. I agree the right looks stronger, and needs some more work. I wouldn't pull any further until you even it up.
Will do.
A solid backdrop behind your tiller tree would help the visuals. I would put up something rigid that you can see a tracing of your limb curve on as you go. a tiller stick will enable you to hold it at the point I see it in the last pic and make the tracing, a lot of folks don't care to use a stick, as it is not the best to keep a bow drawn for to long, but long enough to make a quick trace on the backercoard, then you can tack it up behind the tree. The idea is that you can flip the bow left and right to see differences easier.
I am working on a backdrop, believe me. Just haven't found a big enough piece of cardboard to put up there yet. As a substitute for tracing and flipping would pictures of the bow from each side be worthwhile?
another thing to keep in mind is that as you near full draw with your pulls being the desired finished draw weight, you might want to stop 2 inches short. by the time you have shot the bow in (a couple of hundred shots) at the reduced draw length, and finished sanding and any final radiusing, you might find a slight loss of draw weight or need to touch up the tiller somewhere.
Ok, I will keep that in mind and not go over 26" draw before shooting it some.
twist: http://www.primitivearcher.com/smf/index.php/topic,27206.0.html
Does the thickness run off to one side where it is twisted, or do think the wood varies in the twist area? maybe softer
I need to take a picture from the end so you can see what is happening. After reading that thread I can see I have mislabelled it. The limb is not pulling off to one side, it is much more of a propeller twist that doesn't change from unstrung to braced to drawn. It might get slightly worse when drawn but not by much. I will check the limb thickness to be sure I didn't scrape in a bevel, but I have been watching for that and have kept everything pretty even side to side so far.
Now that it is braced I will take a string alignment pic as well and post it, in case I am missing something there. You will probably be able to see the propeller from that as well.
Mark
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Since I have managed to get this far I now need to consider what I am doing with the levers. I left them chunky in case I needed to correct anything but they need to be thinned down in the end. Currently they are 3/4" thick full length and taper from the 1.5" limb width to 5/8" at the tips. The overlays are another 3/8" thick on top of the 3/4".
I was thinking of narrowing them to 3/8" or so at the tips and having a nice, smooth arc from the nock grooves to the working limb and having smooth sides on the nocks with the string groove only across the back of the lever in the overlay. Thickness can be tapered from 3/4" at the limb end of the lever to whatever works at the tips.
Something like this:
(https://i.imgur.com/kTR2Bwp.jpg)
All thoughts/experiences/ideas are appreciated.
Mark
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Hi Mark,
As a substitute for tracing and flipping would pictures of the bow from each side be worthwhile?
what ever works best for the guy doing the tillering. Some take a pic, make it semi transparent and flip it in an overlay with photoshop or gimp. I was inspired by DC to paint a piece of underlayment with chalkboard paint. http://www.primitivearcher.com/smf/index.php/topic,64606.0.html (http://www.primitivearcher.com/smf/index.php/topic,64606.0.html)
I have been watching for that and have kept everything pretty even side to side so far
the wood might be weaker there somehow. as it is in the same area as the bend that gave you difficulties. If the limb does not want to roll of to the side excesssively and cause the grip to twist in your hand as you draw, then I would leave it alone for now and continue on. There is a chance that you might not make your intended draw weight if you remove much more wood in that area. shoot it in first at 26" and decide later if there is a pressing need for correction.
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Despite our annual blast of winter in March (welcome to Canada, eh?) I managed to get some work done today. The handle got roughed to width and I worked on the limb balance. The handle is wider than I expected so I may take a bit more off once I am at full draw in the tillering. Assuming I get to full draw without pieces flying around.
First, a string alignment shot from the left end:
(https://i.imgur.com/S7tBJrI.jpg)
And from the right end:
(https://i.imgur.com/0ROrZE3.jpg)
Pulled to 17" again after I worked on the right limb some:
(https://i.imgur.com/bNIcGgC.jpg)
It looked close enough to me (rookie eye and all...) to start working towards my target draw weight again. After the work above it went to 24" of draw at 30lb and I stopped there because everything flexed so much getting there that I was flinching waiting for the explosion. First time I've ever tried to bend wood like that and it was scary as hell. Still in one piece, though ;D:
(https://i.imgur.com/MATg8zR.jpg)
I stopped at that point for a second opinion on the bend (after the big pull that right limb still looks a bit strong to me) and because my toes were dying in the cold. On the plus side, I have about 1/4" of string follow immediately after the bow is unstrung and it recovers to nothing overnight. With only a 30lb draw weight I assume I shouldn't have much string follow, but it is still nice to see.
Mark
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Canada? must be east of the rockies, well you almost fooled me with the green grass pic until I realized it was another bow. I'm a bit NW of you in Alaska. 4' on the ground and -10 F. in the morning. springtime!! It does warm up nicely during the day though, lots of sunshine.
the limbs look about as even as I can tell from the pic. That twist fools the eye I think. the light looks like it is coming from low and too the left. maybe a pic with the light from high center? (to minimize the underside of the left limb that shines) Tack up something dark to those shelves for a backdrop behind the limbs please, I would hope that some else would comment also, as I am not the best eye at PA, that I know.
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Canada? must be east of the rockies,
Yep, just east of the foothills in central Alberta. We don't have your snow but it was -20C all day today, which is way cold for us this time of year. March can be a horrible weather month, though, and a huge tease with hints of spring and then lots of snow and blasts of cold.
the limbs look about as even as I can tell from the pic. That twist fools the eye I think. the light looks like it is coming from low and too the left. maybe a pic with the light from high center?
The light is coming from the big shop door, otherwise it is a cave in there. I will try a pic with the door closed and just shop lighting to see if it is any sort of improvement. I will also work on a backdrop. The shelving was super convenient for a solid tillering tree mount with room to move away while pulling the string, but the busy background is a significant problem. My end goal is a large sheet of cardboard painted a solid colour with grid lines on it for comparison but I need the cardboard first.
I do appreciate all the help, I never would have got it this far without your assistance and the comments from others.
Mark
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Mark, I just want to tell you that I've been lurking on this thread and learning a lot, as I really hope to build a bow like this some day. So, there you have it: You really aren't the least experienced person here. ha ha
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WB,
Thanks for the support, I know just where you are at. Don't give up on making bows, I have been looking to do it for years now and have several red oak boards I bought 4 years ago intending to get on it back then. Stay with it and things will line up for you eventually.
Mark
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Thanks for the encouraging word. Two things stand in my way at the moment: First, don't have a garage or workshop, so I don't have a place to work until the weather warms up. Second, I suffered a bad concussion a few years ago, and I live in fear of having a bow blow up and whack me in the head. That would be what is technically known as "a very bad thing." So I've been reading a lot and trying to decie if this is really something I can/want to try.
Anyway. I appreciate you and all the other guys on here who share your journeys. Fascinating stuff.
T
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Second, I suffered a bad concussion a few years ago, and I live in fear of having a bow blow up and whack me in the head. That would be what is technically known as "a very bad thing."
I can see how that would colour your approach. In that case you should look at backing any bow that you do make, just for the extra insurance that any failure will be on the belly side and not involve shrapnel flying everywhere. Using a boardsports helmet while shooting doesn't seem like a bad idea, either.
Mark
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No tillering shots today, I thinned the lever tips and left everything else alone.
First, a back profile shot since I didn't have one earlier:
(https://i.imgur.com/i4hwjt0.jpg)
The levers from the back and side:
(https://i.imgur.com/1J2fqpq.jpg)
(https://i.imgur.com/tkWEZcc.jpg)
I need to complete thinning the tips a bit more but I wanted to put it on the tree to be sure the levers are still stiff enough after I thinned them down. I plan to reduce the lever thickness in a straight taper from the limb end to the tip and clean up the ends with smooth edges/corners all around.
Mark
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Finally got a more useful backdrop in place and took pics again with it.
Unbraced:
(https://i.imgur.com/t3ec9jM.jpg)
Braced:
(https://i.imgur.com/jWlCLrH.jpg)
Drawn to 23", with and without the flash:
(https://i.imgur.com/Yb2ifX9.jpg)
(https://i.imgur.com/piJUIVK.jpg)
Mark
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Hi Mark
easier on the eyes now. Being that your handle width is just a little less than the limb with, I wouldn't be afraid to see if I could do the rest of the req'd tillering on the inner limbs. I'm seeing the right inner needing more scraping than the left inner. But i doesn't take a whole lot of scraping to make thing change in the last few inches. looks good. just curious what you plan to shoot for arrows and how wide is the arrow pass?
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I wouldn't be afraid to see if I could do the rest of the req'd tillering on the inner limbs. I'm seeing the right inner needing more scraping than the left inner. But i doesn't take a whole lot of scraping to make thing change in the last few inches.
I will work on the inner 1/3 of the limbs and see how it goes. I thought the right looked stronger than the left as well but wanted to see what other eyes saw. Things were starting to move pretty quickly before I got to this point, so I will be careful to sneak up on it as much as possible. I can see it would be very easy to miss your draw weight with just a couple minutes of impatience at this stage.
just curious what you plan to shoot for arrows and how wide is the arrow pass?
Arrows are going to be cheap fibreglass ones to start with while I sort what I need longer term. I am planning on cutting in to 1/8" or so short of center for the pass. Haven't decided if I am going to make a shelf or put a stick on arrow rest on it. The arrow rest is easier but a shelf is more traditional.
Mark
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Looks great, Mark!
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fibreglass ones to start with...................I am planning on cutting in to 1/8" or so
the cut in shelf will make it easier to shoot straight with the arrows you buy off the shelf.
Primitive arrowmaking can be more challenging than primitive bow making.
I can see it would be very easy to miss your draw weight with just a couple minutes of impatience at this stage.
Some claim it is harder to make a lighter weight bow than a heavier weight one because making tillering adjustments on thin limbs can become touchy or finicky.
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the cut in shelf will make it easier to shoot straight with the arrows you buy off the shelf.
Yeah, it will be more forgiving that way. The problem with the cheap arrows is you get no spine selection so these will be somewhat stiff for this bow, but more suitable as I work up in weight on future bows. I expect the first couple light bows to end up as 'guest' bows for those who come out to our place and want to try a few shots. Knock around, cheap arrows seem pretty well suited to that duty.
Primitive arrowmaking can be more challenging than primitive bow making.
I have little doubt of that.
Mark
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The problem with the cheap arrows is you get no spine selection so these will be somewhat stiff for this bow
I think i know the ones you are looking at. I buy them for the kids to loose shoot. you can always add point weight if they fly too stiff.
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I think i know the ones you are looking at. I buy them for the kids to loose shoot. you can always add point weight if they fly too stiff.
They sound very much the same, with the same mission overall.
Mark
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I finished the initial tillering today (at least I think I finished...) and got to 26" draw length at 30lb.
Still lowish braced, but after all the scraping was done:
(https://i.imgur.com/1eaZ0y4.jpg)
Pulled to the 25" peg hole, which is actually closer to 25.5" draw with the thick handle and the peg diameter added in:
(https://i.imgur.com/iozwHYJ.jpg)
(https://i.imgur.com/yn9RS7I.jpg)
The right limb still looks stiff to me in the pictures, but it was less noticeable standing there looking at it. I took a few scrapes on the strong side of the left limb and managed to remove almost all of the twist that was there. I am pretty happy with that outcome even if I end up at 29lb because of it. I plan to try heat treating the bow as well, so I will likely gain some weight back there if I went too far getting to this point.
My string arrived today, so I will be able to actually string it tomorrow and take some pics with a proper string in place as well as a full draw picture. I have cleaned up the levers and now need to cut the handle and arrow pass in before arrows arrive next week.
Mark
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Worked on the levers, handle and arrow pass the last couple days. Took forever to get the handle and pass done. I need to find a better way to rough out the arrow pass, working on the side grain on maple was nasty in that small area. Too small for a rasp, too big for a small file, etc. I have seen people say the maple boards in big box stores are soft maple, but if this is soft maple I don't ever want to work on the hard variety.
(https://i.imgur.com/lPPbfNJ.jpg)
(https://i.imgur.com/lPWYZvN.jpg)
Mark
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Last pics before I shoot it some, forgot to get my wife to take a full draw shot before I left the acreage. Next time, I guess.
Full brace, which is more than I wanted but the string is as long as it is ever getting...
(https://i.imgur.com/x8XIXfN.jpg)
Drawn to just under 26". The left (top) limb is definitely weak and the twist came back with the higher brace height. Hopefully heat treating adds enough weight that I can get the twist out and not miss my target weight.
(https://i.imgur.com/5Jt2eHh.jpg)
Arrows are here on Tuesday if amazon holds up their end of things so will be shooting it then if it all works as planned.
Mark
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It's officially a bow. Only took a few shots at a tree as my straw bales are buried in snow at the other end of the acreage, but it has now flung an arrow and didn't explode getting there. I will need to dig out a sled to get a few bales closer to my shop to do the real shooting in. Hopefully tomorrow or Thursday that will happen.
And the obligatory full(ish) draw picture:
(https://i.imgur.com/XmhJ14R.jpg)
Mark
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That's a beauty, Mark! Congratulations.
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Thanks, I will post a couple more overall pictures after I shoot it some and get a finish on it.
I'm still amazed that a stick will bend like this and that it didn't blow up during tillering.
Mark
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Yeah, it seems like one of those little everyday miracles when something like that works. I just bought myself an oak board and a few tools, and next week I'm off work, so wish me luck. :)
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It sure does feel miraculous. Good luck with yours, I hope it turns out like you want.
Mark