Primitive Archer
Main Discussion Area => Bows => Topic started by: simson on July 28, 2013, 01:16:30 pm
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Some guys asked for a buildalong – I will try it.
I have done several hollow limb bows, some examples are posted here:
http://www.primitivearcher.com/smf/index.php/topic,34915.msg460154.html#msg460154
http://www.primitivearcher.com/smf/index.php/topic,34898.msg459925.html#msg459925
http://www.primitivearcher.com/smf/index.php/topic,38380.0.html
http://www.primitivearcher.com/smf/index.php/topic,41177.0.html
http://www.primitivearcher.com/smf/index.php/topic,35613.0.html
The tools needed are:
(http://i1252.photobucket.com/albums/hh576/orangesimson/golden%20chain%20tree%20take%20down/P1010385_zps5bf671bd.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/golden%20chain%20tree%20take%20down/P1010384_zpsc6f673c6.jpg)
Hollow limb design only makes sense on high crown staves.
I have choosen a Laburnum stave, about 2,5 - 3“ in diameter and 66“ long.
After debarking I saw this would be not an easy candidate, very wavy and lots of knots. I run it through the bandsaw and this were we were at the moment:
Side profile
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010804_zps8a5f5cea.jpg)
front profile
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010805_zps6a40b114.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010806_zpsc17b443d.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010807_zps32627ca5.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010808_zps07853582.jpg)
here you see the fungus inside the stave, some of the outer rings are intact, but the fungus did spread over the rings …..
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010790_zps2e527c42.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010791_zps5f2a949f.jpg)
My first thought: let it be firewood!!!
But anyway, it doesn't matter if this will became a bow or not – showing the process of hollow limb can be done on every piece of wood. Let's try it and don't expect a shootable bow ...
This are the disadvantages:
- very thin ringed
- not matching string alignment
- massive dogleg in one limb
- not matching reflex of the limbs
- severtal knots (not avoidable in layout)
- some holes
- a fungus inside, growing from the center pith outwards, but was not intelligent enough to do that growing in the same ring
This are the advantages:
- nearly no twist
- it's laburnum – one of the prettiest woods
- it's laburnum – one of the best bowwoods
- and it has everything what we call character – so it's a challange
the fungus has produced that bright spongy material, nearby is a dark brown which I think the tree has produced to stop the fungus - this is very hard and brittle (inlayed minerals?) and makes the tools quickly dull. The olive is the origin color of the heartwood, the white is the sap – this is the good stuff
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010792_zpsc487cbe4.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010793_zps2a196009.jpg)
on this little stave I can use mostly only the gooseneck scraper and the 'Geissfuss' (transl. word by word: 'goat leg') don't no how you call that wonderful tool
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010794_zpsdd5b9256.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010795_zps046a6c1e.jpg)
the result so far
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010796_zps7a2e6384.jpg)
will continue when I have time again …
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I'll be real interested to see this turn out, are you going to even try to get to shoot?
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Oh BOY!!! I'll be following this! :) Is the orientation of the hollow part of the limb the same as an ACS bow?
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Thanks for doing this Simon, gonna be very interesting to follow and learn from. Like the way you assess your woods
properties and your staves pros and cons to lay out a plan before starting. I'm learning already.
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Yes Sir,
Thank You, I'll be watching...
-gus
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Your the man I'm making some popcorn now. >:( Thanks for or time.
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Is this really happening? Dream come true! Watching closely.
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Wow, Blimey... you look to be as foolhardy as me ;)
We are gluttons for punishment... hope she works out.
V interesting project.
Del
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Zion:
Yeah, will try it - we will see a bow or firewood
Cody:
I think the advantages of the hollow limb design are: It will add additional strength to the bow, without more wood (fold a sheet of paper like the letter U - and it is stiff!). Will say it is mass saving. And, the flattening out alone will create a movement in the limbs. Much less wood and much less stress. The compression stress concentrates in the 'bellywalls' (at braceheight), while drawing the bow the hollow limb flattens out, the neutral plane changes and the stress is contributed in a wider area the longer the draw. In other words the hollow limb design affects a much higher drawweight than a 'normal' designed bow (steeper f/d curve in the first inches of draw) I think this is a difference to ACS bows, the hollowed out here isn't that high and because it is a stiff laminated glass bow it cannot play with the flattening out advantage. The rounded shape of an ACS design saves mass and gets stiffer (sideways). This is good - but I'm talking about very deep hollowed out dynamic limbs! Hope you understand me, I'm hard struggling for the English words and grammar...
Badly Bent:
Too nice words from a master!
Gus, sgtchad, Carson:
nice you are interested
Del:
mmmmhhhmmmm ....... yes, that is obviously true
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I forgot to mention: laburnum = golden chain tree
Here we go again to session 2
This stave is by far not the best candidate to show the advantages of the hollow limb design, but it's an interesting challenge and the beginning is already done.
I do the hollow limb design normally only the best intact staves, so it is quite easy to chase an inner ring and follow outwards to the tip as a guideline. Usually I have then little work to do the taper outwards.
Not so here! The fungus has spread over the rings and destroyed the wood. I have to take off the complete bright spongy stuff, even if it 'hurts' an inner ring. This can cause stability problems (warping sidewards) or coming out of tiller, but I have to live with that. If one of the two belly walls gets too thin , it will be overstressed. I have to compensate that with slightly more thickness in the rounded middle.
A first floor tiller test shows heavy warping, as expected. To get that a bit better I cut off 2“ from the lower limb which has a heavy curve sidewards.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010797_zpsc8b0501b.jpg)
Cut of 2” from the upper limb also.
Didn't get enough for string alignment, heating is nessecary – we that later!
For now continue hollowing out the limbs
here two pics of cutting in intact wood, results in nice long chips.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010798_zps5fd814cc.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010799_zpscf25165e.jpg)
after working with the goatleg (don't know the right word):
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010800_zps6f9d7526.jpg)
after working with the gooseneck:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010801_zpseed37ad5.jpg)
working out knots and holes to nearly the same thickness as the surrounding area:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010803_zpsdd118f18.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010813_zpsc2750534.jpg)
here is a pic how it looks now:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010812_zps724f56ac.jpg)
here is a grain wave on one of the belly walls (problem again):
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010814_zps99bf1482.jpg)
the same spot:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010815_zpsd5ccc8a6.jpg)
such areas must be carefully watched, hope I can take off wood here while tillering
marking thick spots and working down:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010816_zpsba49a994.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010817_zps36986536.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010819_zpsbae547d0.jpg)
enough for today, here is the leftover of the second session (just the same amount as the from the first):
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010822_zps99396c7e.jpg)
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This really puts a new perspective on the whole process. I gotta say i'm most interested in how you will tiller it. Are you the only one that has come up with this? It obviously works haha.
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so are these things really fast?
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Something for the bucket lost, that's some pretty wood, I would think that this design would focus all the compression on the outer walls of the curve though
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This is intriguing, I will be watching this one....
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Simon I believe that tool your using is called a bent gouge. How many hours have you spent on carving this bow so far?
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Simson, that sure is an ugly stave for a build along but I bet you can pull it off if anyone can!
Some one ask if you came up with this method? I have seen one of the Norwegian guys doing a hollow belly on
elderberry staves but those have a big pith down the middle. cheers fiddler49
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Wow, that's gonna be interesting! Ugly stave, would probably not have gotten another look if it weren't laburnunm. As I see this, the main reason for making it hollow is that the center is rotten? Waht is the motivation on intact stave. If you say "good looks" that is totally acceptable to me ;D
I'll be watching with interest!
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The way I see it is the best time to do a hollow limb is when you have a high crown. Correct me if I am wrong.
Grady
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Interesting for sure. I will be watching.
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Seems to me that having a hollow limb allows a larger belly surface, thereby increasing compression resistance.
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It looks to me also that tension required to spread the limb would reduce the tension on the back that would normally stretch the back to add tension. This in affect would give a higher draw weight with a lower back tension because some of the draw weight would come from the tension required to spread the limb rather than stretching the limb.
Grady
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I want to keep up with this build. Some interesting theories for sure.
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Zion:
I came to this design myself by doing experiments with different things. But everything was on the planet before we thought on it. Once I saw an archeological yew bow found from Switzerland, which had a furrow in the middle of the belly. Long time nobody could explain the reason for it, maybe this was the beginning of hollow limb design. Perhaps the future brings new finds ….
Btw. Some Indian arrows had grooves to stiffen the shaft and prevent twisting, that is the same principle.
Squirrel:
As explained, this design is mass saving and has other pros. So, more energy goes into the arrow and mot in the limb. See answers above and below.
Newindian:
Yes, you are right! So probably not every wood can withstand this (is to be checked out). I have done it (ok, a mild version) even with hazel (not good in compression) with very good result. My thoughts on this point: at Brace you will have a given thickness of the bow limb (measured from the crown to the belly walls). What happens when you draw the bow? The hollow limbs flatten out, the thickness of the limbs are now less than at brace. It’s like drawing another bow, one with thinner limbs. This affects a comfortable draw, the increase in the f/d isn’t that high than normal and, main point, that thinner limbs creates lower stress on back and belly.
The optimum is probably when we can create a limb design that can match the horizontal and the vertical forces at a specific drawweight. Will say, a good bow is built near the break. Hollow limb design should do the same also with horizontal forces, the flattening out should be that much as possible.
Here is a quick sketch to make it a bit clearer.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010864_zpsf60c530f.jpg)
Ssgtchad:
Thanks for the word (goatleg = bent gauge)
Time spent: about 1h for debarking, 0,5h layout and bandsaw run, 1,5h first session, same for second session, will watch the upcoming time if you are interested
It takes me more time to do that buildalong, taking pics, photo bucket, computing, searching words and so on …
Fiddler:
Mike, thank you for your trust in me, I will do my best.
Reason to do the hollow limb design here is because I see no alternative. A conventionally design on this stave would end with a 15 pounder, because so much wood has to be taken off. The invention of hollow limb design: please see answer given to Zion, above and to Cody (missilemaster) on page 1.
I also have some elder staves with big pith (need still seasoning), they are candidates to hollow out for sure.
A theme, I think about, is Bhutanese bows. You know the Bhutan archers use bows made from a half split of a thick wall bamboo calm. They use it inside out, the inside of the calm is the back and the outside is the belly. This is the similar principle, but there is a big difference in the horizontal forces: in Bhutanese bows you will get tension on the back and compression on the belly when the furrow flattens out – with hollow limb design you will get the exact opposite. Please see sketch above.
Jodocus:
Thanks please see answers above.
Autologous:
Yes, Hollow limb design only makes sense at high crowned limbs. And yes, some of the bows strength comes from the resistance from flattening out. This load must not come from limb thickness like in a rectangular cross section. So less wood is necessary and the result is less stress. See sketch above!
All:
Again thanks for interest, this is a good discussion. And it seems there is a lot to discover.
Session 3:
I have marked some areas in red where wood is to be scraped off. I have meanwhile mostly changed over from the bent gauge to the gooseneck. I control thickness with my fingers, but have to react every inch on other problems – this stave is really an adventure!
Upper limb
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010825_zps5ee4f768.jpg)
lower limb
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010826_zpsb3534ca0.jpg)
near fade, heavy destroyed wood ….
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010827_zpsa8e1bbb9.jpg)
working out knots/holes
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010829_zpsceec7976.jpg)
knot/dead branch near fade
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010830_zpsa98114a5.jpg)
also fine correcting side taper
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010831_zps90d2927f.jpg)
I did some floortiller, I can bend that thing to a straight line (all the amount of reflex). Sorry no pic, would need an assistant. Two things are evident: first the stave tends to warp to the right (seen from archer, upside up) – so need to bend in the handle section to the left side; and second floortiller shows a much more stiffer lower limb (that one with the dogleg) – so needs to be scraped down and reduce the too high reflex.
Let’s begin with the last, reducing reflex. I will do that in two portions, one at the dogleg and then one near the fade.
That dogleg in the lower limb causes most of the uneven reflex in the limbs. I will try to heat it out a bit to bring the side profile more in line
here is a sketch what I want to do
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010865_zpsa500cb5e.jpg)
now here is the heating setup
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010852_zps8c0e3ff7.jpg)
For heat bending I use paraffin oil (cheap at Ikea). It damps (and stinks!), when the heat gets too high. Good control mechanism.
The stave is clamped in the vice and secured with an additional clamp (left from vice). As weight I use a canister, bound on the stave. Of course this done before heating. Now measure the distance to the floor. As you see, I have a plastic clamp on the tip and a ruler leant upon. With this setup I can easily control the bending process, without interrupt the heating up.
Another good trick is an old can with a cutting lengthwise, this allows the heat going round the whole limb. It is held in place with pliers, simple and super effective!
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010849_zps88de179e.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010850_zpsb51446de.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010861_zps49275dfc.jpg)
I got the tip moving about 3” to the string. That is good, but not enough. Take a look at the pic, handle is still not parallel to my bench (both tips are laying on the edge of my bench). I leave it for now at it is; perhaps I will give it later another try.
Aren’t that beautiful colors on the oiled sections? That’s why I like that wood so much.
Now is time to bring the string in line. The string is about 1,5” off.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010845_zps53f8971c.jpg)
Noticed the handle is heavily damaged by the fungus, more than I thought. Problem here: It should be stiff and I need to heat bend the stave here for string alignment. I will do that with a longer run and less heat than normal. Perhaps we will need additional reinforcement here, that should be a matter for later.
This way it is clamped in the vice, notice the melting glue stick for preventing damage on the limb
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010857_zpsd9bdb467.jpg)
how the can is held in place while heating
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010854_zpse32d0d4f.jpg)
I heated down the 1,5” offset carefully with low heat (way lower than I normally do).
After cooling down, I saw that fret ( see earlierpic) on the handle had opened a bit. Well, I have expected it and it happened. No nerves for now to get on, will think over a repair. Any suggestions?
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010858_zpsb6302d11.jpg)
the leftover from session 3
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010846_zpsbe772f94.jpg)
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Great thread... I like the sketch.
Del
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Great build-a-long. Good luck with the repair. Those sorts of things I tend to think on for months before doing anything with it. Hope you get some good ideas here.
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very cool, keep it coming
chuck
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I like your craftmsmenship and ambition there simson.Thanks for sharing this.I for one will be watching.
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Like Del i like the sketch,sound theory to extend the neutral plane in full draw with minimum weight.
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Simson, have you tried this design in combination with sinew backing?
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Thanks again for your interest. would be nice if somebody else try out HLD, so we could compare the results.
Great build-a-long. Good luck with the repair. Those sorts of things I tend to think on for months before doing anything with it. Hope you get some good ideas here.
Carson, I didn't tried it yet. But will do, perhaps in the coming winter (more time).
Your Question reminds me on an interesting discussion on PP with Dave D. (aka Woodbear). Here is what he said:
I find the concave limbs to be an interesting design. I have a short sinewed west coast bow that ended up concave toward the back as opposed to your concave belly design. Mine was due to the sinew pulling the thin (1/8inch) limb into the concave shape. The tiller of this limb was quite difficult. The limb tends to be stiff and then give suddenly as the concave shape flattens.
It is a great experiment. Please keep us posted.
and later:
Simson,
Great job on that bow, looks like a time warp from 1000 years ago on the west coast. I like the arrow as well, both the bow and arrow have that classic shape that says hunting in the wild. The last two photos are dramatic primitive hunter at dawn. (Worthy of the banner I think)
I did not get any break over with my bow in the draw, I think it all happens when I brace the bow, and makes bracing the bow a bit of an art of training it to the right shape by careful flexing and feel.
Regarding the concave shape, it does make the limbs stiffer per mass. It also theoretically loads the back as well as the outer edges of the crescent cross section more than a filled flat belly would, for equal mass, which is fine so long as the wood can take it.
Juniper is good in compression is my (limited) experience. If you have no set you may have some more draw available, but I think you are pretty good where you are. The tiller looks great to my eye, even with slight flat spot on the lower limb. If you remove wood to gain draw, you will necessarily lose some weight. Unless the bow is strained more overall, or more evenly than now, the net result at the longer draw will be less energy, as the price for the more “normal” (?modern?) draw.
Love the bow. Keep up the great work.
Dave
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Session 4: Floortiller
I don’t like the usual floortillering method very much, because you look on at a steep angle to the limbs. It is a lot better not to look directly, but via a large mirror placed some yards away. This allows watching in a more rectangular (word?) way.
I found another way to do the ‘floortiller’, not on the floor but horizontally.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010833_zps1e2c3d9c.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010835_zps97f9aa1d.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010836_zps56ba36fb.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010837_zpsba5db624.jpg)
In the pics above you can see my method of tillering in my vice via leather shoes + cord.
This works well for me, I can immediately react on the stiff points and take off wood with the scraper. This allows fast working, no need for taking off and on the ‘string’ just open the vice and pull horizontally. The cord hangs always in the vice.
Pulling the stave with one hand I lay my other over every inch of the limbs belly sides. I can feel the bending and can feel also how the hollow limb flattens out. It should do that even over the whole bending limb.
Scraping with the gooseneck and using the thumb as a guideline to get even thickness:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010838_zps99d44ad3.jpg)
This process is done several times, until I get the limbs bending so far enough for long string tillering. And of course the limbs should bend simultaneous.
carefully woking at the nocks with sanding linen:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010839_zps06c4d5b9.jpg)
Btw, I don’t like rasps that much, you don’t feel the grain! I like thick and sharp scrapers, they take off wood excessive without leaving marks and goes with the grain over the humps and bumps. A rasp is a good choice to plane knotty areas, esp. when knots have really hard old or dead wood in them.
This is a good trick for sanding in the grooves over humps. It is a flexible melting stick wrapped in a sanding net:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010842_zps162f6699.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010841_zps95b97a49.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010840_zps59f8af04.jpg)
Here is the leftover from the 4 session
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010872_zps0eb54596.jpg)
session 5: the handle repair
Finally I decided to do the repair on the handle. My first thought: soak it in super glue and wrap the handle with strong hemp cord. But that crack made me nervous, so I split off the half of the belly to examine how it looks. Catastrophe!
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010868_zps30f0c0da.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010869_zpse722c609.jpg)
A miracle it stayed together while floortiller and long string tillering. Big damage here, the fungus has made a tunnel of spongy white stuff. Only millimeters of the intact side walls are left, this affords a strong repair.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010870_zpscbd85624.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010871_zps47dc309d.jpg)
So what to do?
Next idea: Sand it down and glue on a new piece off intact wood. Thinking over this, I wondered if a take down sleeve would add strength in that area.
We will never know if we don’t try!
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010873_zps83cd047b.jpg)
making take down bows from billets is ok, but cutting through afull length stave always makes me crazy …. but in this case probably the best
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010876_zps971721e3.jpg)
a take down sleeve was quick made out of junk and the two halves a bit carved to get the sleeves on
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010877_zps222972a5.jpg)
The sleeve ends of the limbs need a good strengthening. Fortunately I found a matching piece of golden chain tree in my fire wood.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010879_zps1d1981cf.jpg)
Next step sand down as much as possible to intact wood and glue on a piece of wood in the handle/fade area.
Marking the new 'fade overlays' and cutting out
this are the parts I have now:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010881_zps668bd5a3.jpg)
Glueing on the new fades:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010882_zpsaff94b68.jpg)
After a dry mounting I felt again warping sideways. To get that matched, I have to glue on the sleeves a bit out of the line. I will glue on the sleeves separately for most safety, I hope the string is then in line. I want to avoid heating again, when possible. Using very thin Epoxi, filling the grooves and valleys is no problem.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010883_zps6ef9db21.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010886_zpsbaa97634.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010887_zpsa38439ef.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010888_zps937c2d60.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010889_zps72c3e991.jpg)
It seems like it does work. We will see. The glued on pieces are looking very ugly, let’s bring them in a nicer shape. First cut off the excess with the hacksaw, then rasping and rough sanding.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010892_zps6844f490.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010893_zpsce3f4b4a.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010894_zps6cda0ae3.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010895_zpsc38dd404.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010896_zps1b828358.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010897_zps2281c1ec.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010898_zps998fd16c.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010899_zps143f9d80.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010900_zps87d2e9ba.jpg)
Now is the time for more tillering, and cutting the bow to its final length. I go for an asymmetrical, top limb is about 2” longer. I have to decide the final upper and lower limb
I will do the tips soon to get her braced, any suggestions for the tip design? Overlays, pin, self, wrapping, …?
Here is the leftover from session 5 with the cut offs from the glued on pieces
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010901_zpsaa17b923.jpg)
I’ll continue in a few days, upcoming decisions are:
1. symmetrical or asymmetrical bow
2. design of tips (overlay, pin, self, wrapping, ...)
Let me hear your suggestions and thoughts
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Wow! What a save! I think it looks even better now. I've really enjoyed watching your progress working through this stave. Thanks.
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I feel honored just being able to read this thread. Your skill is absolutely unequaled.
Grady
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Incredible craftsmanship. Thank you for sharing.
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Get down dude :o :o :o :o
I have a stave with a high crown, and thought about scraping the belly to match.
now i see it could be done. :)
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I think you've proven that you CAN make a silk purse out of a sow's ear.
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Too cool.
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I think you've proven that you CAN make a silk purse out of a sow's ear.
I would not go as far as to say that, but he definitely could make a bow out of one.
Grady
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Just like watching Rembrandt paint a masterpiece. Thank you for sharing this.
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I feel honored just being able to read this thread. Your skill is absolutely unequaled.
Grady
+1 you have taken bowmaking to a level unmatched by any I have seen. If you pull this off I will be forever in awe.
Jon
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This bow is so amazing! I feel so underqualified to say "I make bows" when there are craftsman such as yourself making such masterpieces.
I can't wait to see the finished product and I hope it holds together for you.
What'd you make the TD handles from?
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Totally amazing man, amazing!
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Your the man Simon! This is the most interested i've ever been in a build along. Great work.
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This build along is amazing. You have taken bow building to another level. Anxiously awaiting the next session> Dan
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You do very good work, my hats off to you ................ :o 8) :o 8)
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WOW truly impressed ;D. Can't wait to see the progression.
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Nice fix! I would say overlays since its a take down. And thanks for all the time you are spending on this thread. I know how time consuming it must be to take, edit and post all the pictures. GREAT JOB!
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Way to go!
To make that disaster into an advantage...impressive serious skills at display here!!
By the way, my favourite of all your bows so far is the 80# osage recurve with triangular tips you posted last december i think.
That one still makes me drool :-[
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As in bow making so it is in life.
It's how we deal with adversity that makes us the people we are.
Great save.
Del
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This build along is blowing me away! Incredible workmanship.
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Nice save Simon. I have been in awe of your hollow limb bows since I first laid eyes on the whiskey flask one (or was that brandy? ;D). I like your explanation of the tension and compression forces on the hollow part. I also like to think of it as you would a stone arch. The Romans (maybe even pre-Romans) found out long ago that a curved span was a lot stronger (in compression) that a flat one. Which also makes me ponder: If there is compression on the belly side of the arch and the tension forces are the strongest at the backside crown, would there not also be slight compression forces on the BACK side of the outer edges coming back around as the curve flattens out? Sort of how a keystone in an arch resists compression on it's sides and keeps the arch together?.............just thinking..maybe no correlation at all just trying to throw that into the conversation..........
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Thanks for sharing your techniques! It is fun to watch your progress and learn from your approach. I would have broken that piece of wood somewhere during session 1 :) Can't wait to see the next session.
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wow! that is looking sweet. i love the transition of the fades into the limbs. would this design work with yew? if so i may give it a try.
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WOW. Just amazing. Thanks for taking the time to share.
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Looking good Simon. Way to go on that handle fix, thats a solution I never would have thought of. Also like how you managed to blend in the added handle wood for a smooth transition, a lot of impressive work going on in this build along. I have to say thats one tough stave you chose for this project. Can't wait for the next installment, were rooting for ya man. :)
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Nice work. A brave attempt and the best way to become great at bow making.
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All:
Sorry for the late response.
Currently I'm working on my new shop, really lots of work to do. Therefore I cannot be here every day, but I will do my best to make not to big pauses.
Thanks again fellas for your nice complements, but you should definitely wait until this thing becomes a bow (still not sure it does).
Mad Max:
Yes come on, let me see your HLD bow. I believe this design has a great potential.
Weylin:
Have you got my message? I'm not sure if it worked …
Christian Soldier:
this is from what the sleeve is made of. It's a tool called 'dritte Hand' (in German which means translated word by word 'a third hand' don't know if the title contra choc is the English word or just a phantasy product.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010904_zps57c03739.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010902_zps9ca4e3f6.jpg)
The two pipes fit perfectly
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010903_zpsb2bf9ff8.jpg)
This tool is used to install things like boards or plywood to a ceiling. I have two of that and both are junk, because the d......d plastic grip broke of. Now they are laying in the box for metal trash and are waiting for a new birth as t/d sleeve.
dbb:
Nice you remember that bow, It is still one of my favorites too!
Del:
Thanks bro!
randman:
Good points! I believe there is many we can discover in HLD bows. I'm waiting on your examples. Thanks for your input!
BowSlayer:
I see no reason why not, esp. golden chain tree behaves very similar to yew. Give it a try!
Badly Bent:
Thanks for your nice comment and yes this is not the best stave, as said I took it out of my firewood ...
steve b.:
oh, it's really not my motivation to get a place in the bowyers hall of fame. I have learned all I know about selfbows on PA and PP and out of books. I simply want to give a bit back …. and a few guys requested that buildalong. But thank you!
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Session 6: Tips
Some guys requested some time ago a buildalong horn insert (wedge) tips. So let’s do it here!
We need two matching wedges, I have a bunch of them prepared from brown black and colored horn. First make two rectangular pieces of the desired thickness (about 3mm is ok).
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010905_zps64f7cf35.jpg)
Next sand down to a wedge, tapering to zero on one end
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010907_zps4cd7a710.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010908_zps9a4a6984.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010909_zps08b403f0.jpg)
I use a handy belt sander for this job. Use little wood boards to press the horn down, otherwise you sand your fingers flat (I made this experience!).
Be sure the pieces are matching.
Now the slot in the tip:
Camp the bow in the vice and mark vertically where to cut and horizontally how far to cut, be sure both tips were matching.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010910_zps978170fd.jpg)
Cut the slots in the tip ends, I use a sharp Japanese hacksaw.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010912_zps0d0c44e0.jpg)
this how it looks after the first cut – now comes the tricky part:
clamp the tip end with a plastic clamp and saw again just in the same slot as you did the first time
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010914_zps2e70c455.jpg)
The cut should go exact to the end of the slot. Now pull out the saw blade and the clamp closes the slot. Repeat the procedure, next use a second clamp:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010916_zps550ab6cc.jpg)
and voila' here is the result like a miracle we have a v-slot in the tips, exactly were we want it
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010917_zps1ae04ba2.jpg)
The horn wedges should slip in with little pressure, you could use the wife's nail file to get the surface even (when needed)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010918_zps9ef6c661.jpg)
Before glueing try a dry run, here is how it should look like:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010922_zpse04dbe42.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010923_zps3928dbdf.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010924_zps403f23bd.jpg)
Now glue in the wedges, I have used super glue, TB3 and Epoxi successfully.
For now I go with epoxi. I wet all surfaces – the slot and the wedge
Wait til the glue gets a bit sticky, to prevent squeezing out when clamping.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010925_zpsfbdc70fb.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010926_zps248bd54e.jpg)
I use office metal clamps, I like them for little glue-ups.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010927_zps59dbd3bb.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010928_zpsf311c78d.jpg)
After the glue has cured:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010929_zps11b3da17.jpg)
Cut off excess, sand down to the limbs surface.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010930_zpse4d92d61.jpg)
After sanding:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010931_zps2b8c355a.jpg)
And more sanding:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010932_zps7443555a.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010933_zps79ef6e3d.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010936_zpsd84b6bb7.jpg)
from the side:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010937_zps9d416c90.jpg)
I will go for sinew wrapped tips (sorry ssgtchad), therefore I have sanded the tips more roundish.
Wetting sinew and strips of rawhide:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010940_zps8492d7f6.jpg)
Taping the tips and applying hide glue:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010941_zpsb75638f0.jpg)
This is what I will do, forming a rucksack using raw hide and hide glue:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010946_zpsdf4a295b.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010942_zps99f57074.jpg)
The first round sinew wrap:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010944_zpsdce1403f.jpg)
Fold back the strip, second sinew wrap, cut off excess strip:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010945_zps007f4043.jpg)
When the glue isn't sticky, wrap the complete tip with rubber textile to press the sinew in place. (sorry forgot the pic)
The day after the sinew has a bit dried out, after a first sanding it looks like this:
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010947_zps6fa18863.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010948_zps9ef20aa3.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010949_zps50c46901.jpg)
Now we have to wait a few days for complete curing.
Next I will try to string that thing.
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Thanks for the "how to" on the tips,way cool!
Will try that on the next suitable bow
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Looking great Simon. :)
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Those tips are looking real cool, i hope this bow works out! Can't wait for when you start bending the wood >:D
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Do the inserts do anything but look nice? Which they do!
Don
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Very cool wrap nocks simson and in a short amount of time.I'll rememeber that.The taper slotted horn insert was cool too.Nice touch to a bow.
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hello simson,
fantastic buildalong. i admire your optimism, doing all that work on the tips for a bow that is really a challenge. i guess i would have worked with temporary tips :)
good luck with that stick!
ciao,
gian-luca
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Excellent buildalong and detail on the horn wedges and tips. Not seen it done that way before.
Thanks for taking the time and trouble.
I just love sketches... I've been working on the PC at work and it is such a pain compared with a good ol' pencil and paper ;D
Del
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awesome build-along, thanks for sharing!
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Enjoying this build along lot of unorthodox stuff goin on here ! Nice to see new ideas !
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Do the inserts do anything but look nice? Which they do!
Don
Yes, the two glue lines and the vertically horn strip stiffens the outer tip. So you can reduce mass here and gain extra energy on the arrow.
hello simson,
fantastic buildalong. i admire your optimism, doing all that work on the tips for a bow that is really a challenge. i guess i would have worked with temporary tips :)
good luck with that stick!
ciao,
gian-luca
Yeah, you're probably right. But I was several times requested for how to do that inserts. So if this thing doesn't want to became a bow at least the request is done.
Thanks to all for interest!
I have begun with tillering and realized a big problem: the fungus damaged areas are incalculable!
The hold one time and a second later here is a big let off. If I couldn't manage this, I see only one way: scrape off all the fungus portions and go for a light weight bow. We will see ...
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Maybe belly or edge patches can be added to replace the fugus areas?
I did the 'bonkers bow' which ened up more patch than bow, but it was fine!
Del
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Maybe belly or edge patches can be added to replace the fugus areas?
I did the 'bonkers bow' which ened up more patch than bow, but it was fine!
Del
That was a good read on your blog.
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Maybe belly or edge patches can be added to replace the fugus areas?
I did the 'bonkers bow' which ened up more patch than bow, but it was fine!
Del
Del, I remember that bow! It was a great repair you did here. But on mine are more valleys and mountains than an even flat thing to glue on some patches.
Yesterday I hollowed out nearly the complete destroyed areas with sraper and bent gauge. I violated my left hand heavily with the gauge, fortunately I didn't hit the tendons. But had now to interrupt a day or two.
Thanks for your proposel.
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Session 7: The End
Finally found the nerves to continue. As said I scraped of nearly all of the fungus destroyed portions. It was impossible (at least for me) to tiller with this damaged wood. The result is now a bow with very thin limbs 6 – 8 mm. This will become only a light weight bow, but better as no bow.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1020050_zpsb5b8dcde.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1020051_zps3a251622.jpg)
I worked around the holes carefully, here are pics from belly/back
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1020026_zps21f7fe5e.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1020027_zps5f656d82.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1020028_zps5c66d184.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1020029_zps5220a829.jpg)
Ok, the bow was tillered to braceheight and a few inches of draw. It didn't fell good a kinda wobbly. Therefore I decided to cut off the lower tip and make the symmetrical into an asymmetrical bow. (Gianluca was right, I should have better worked with temporary tips).
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010996_zpse65eab94.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1010997_zpsadbcde84.jpg)
So I had to do the inlay wedge once more (waiting again until the glue cures). Didn’t want to wait once more for sinew wrap curing, so I filed in some normal kerfs.
The handle is already done with a two tone leather to hide the ugly sleeves. The grip is a bit upholstered for matching better with the lines of the bow.
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1020003_zps1d5d28e4.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1020004_zpsd3fc2b71.jpg)
(http://i1252.photobucket.com/albums/hh576/orangesimson/hollow%20limb%20buildalong/P1020005_zps7fddc58d.jpg)
Usually I don’t use the tillertree often, except making drawweight measurements. But it is good to get a free hand for the camera.
Have you noticed my cradle? It is a nylon strap (from an old safety belt), this allows the bow to balance out.
On the wall is a sketch paper taped, you can see the increase of bend. This allows to control the limb working the whole length.
The uneven reflex causes a non string parallel handle, I will live with that – don't want a heat on the bow again
after a lot of scaping here and there and some sanding and some polishing and some oiling ...
This was a hard struggle from firewood to a bow!
Long lasting story, but now we are
READY!!!!
I will post pics from the finished bow in an extra thread soon.
Thanks for your interest, your input, your comments.
I’m looking forward to your HLD bows!!!
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Great pics. I agree with letting the bow balance out, the block on my tiller tree is curved so it can rock and find it's own balance.
Del
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Wow.. Amazing.. Great build-along.. Wow did I say Wow
Thanks Leroy
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Simon,
I love the Idea, and your Execution the Hollow Limb design.
You have inspired me to assemble some tools with a Hollow Limb build in mind.
I look forward to seeing the finished bow in another thread?
Regards,
-gus
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That was very impressive! Very innovative. Jawge
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Thank you for your nice compliments!
The finished bow is here:
http://www.primitivearcher.com/smf/index.php/topic,41863.0.html
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I came to this design myself by doing experiments with different things. But everything was on the planet before we thought on it.
Sorry to ressurect an old thread (I haven't been on here for a while), but the question on the application of the mass principal brought me to this excellent build-along.
This now gives me a wonderful perspective on the English Bronze-Age 'Edington Burtle' bow that I got to examine in the Museum of Somerset a year or two ago. This dates from about 1700 cal BC and is a hollow belly design made from Yew. I had thought that I had previously posted pictures on this forum, but a quick search suggests otherwise. Here is a link to a full writeup with photos in another place - I hope I'm allowed to post this link here...
http://paleoplanet69529.yuku.com/topic/54123/The-Edington-Burtle-Bronze-Age-Bow-Photo-Heavy (http://paleoplanet69529.yuku.com/topic/54123/The-Edington-Burtle-Bronze-Age-Bow-Photo-Heavy)
Great work. My thanks for posting once again...
Peter
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Thanks Simon that was exactly what I asked you. Excellent build along!
I moved the John Wayne poster to make room for yours ;)