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Re: KTB Bamboo Arrow 5ea

ragnar wrote:

The improved arrows are in the works, I removed the windings on the front of the fletching, and thicken the diameter near the nock.

Still not enough.
I checked them, by laying it on the tong-ah rail, and slightly pressed at the nock area. The arrows still not lay flat, because of the fat quill of the feathers. Think I try at least one arrow, remove the fletching, and sand the quill down to 1..2 tenth of an inch.

These arrows date back to a time when a naive me still believed that one can buy quality wood arrows for cheap in online archery shops ...

Take a look at Bede Dwyer's video below.  Might be helpful if you haven't already seen it.

https://www.youtube.com/watch?v=7-d5CyOi58U

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Re: KTB Bamboo Arrow 5ea

>>Now<< I've seen it.
Just a confirmation of what I supposed to think.
My arrows mostly not having the tip down inside the rail. And I refrain from shooting in this case.
Now that my relocation is mostly finished, I hope to find the time to modify the arrows, i.e. remove the fletching and sand the quill down.
Other projects had precedence, like finishing a batch of bamboo arrows ...

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28 (edited by ragnar 2019-07-07 16:30:59)

Re: KTB Bamboo Arrow 5ea

Sanding the quill of the fletchings down didn't do it either.
Doing a quick search, I found this video: https://www.youtube.com/watch?v=ESoEgAfexog
Compared to this guy's tong-ah, my is much narrower, less than one and a half arrow diameter. His is about 3 times the arrow diameter, I guess.
I think I got to find me another (and thicker) bamboo stick. What's your opinion on this ?
An image of mine, with an arrow. Hope I got the image upload right this time ...
http://www.koreanarchery.org/punbb/misc … r=1805t886

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Re: KTB Bamboo Arrow 5ea

ragnar wrote:

.
An image of mine, with an arrow. Hope I got the image upload right this time ...
http://www.koreanarchery.org/punbb/misc … r=1805t886

Nope doesn't work for me m8.

BTW, Saracen Archery I believe gives some dimensions for tong-ah.  There are a few sources that host free download of this text in PDF.  I suggest tracking down the text via google search using term 'saracen archery pdf'.  I believe when I made my tong-ah, I consulted the text for dimensions and it turned out correct/functional.

Also, you'll have to source appropriately sized bamboo which is the hardest part really as only nature can provide that.  Finding the perfect shoot with right length and circumference, plus minor to no imperfections is in many way the hardest part.

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Re: KTB Bamboo Arrow 5ea

Nope doesn't work for me m8.

Don't know ... I checked again, from another PC, and I still can see the picture. For sure I also checked immediatey after posting.
Anyway, I'm convinced mine is too narrow. There are just a few millimeter clearance, relative to the arrow diameter, so the fletching seems to work as "pivot point", because it is wider.
I will report back when my updated/improved device is ready.

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Re: KTB Bamboo Arrow 5ea

ragnar wrote:

Anyway, I'm convinced mine is too narrow...

You need specs here m8.  Have you tried ATARN or even the source I provided?  I don't think Youtube is going to cut here.

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Re: KTB Bamboo Arrow 5ea

Have you tried ATARN or even the source I provided?

I need to check how far I come without a login. Nothing will convince me to create one for fakebook.
Checked the classic atarn side, but didn't find specific information. Some stuff remained undone the last weeks, because of a relocation.

BTW, the rear section of my tong-ah, where the arrow rests, is 10mm wide (0,39"), the arrows are 5/16" (8mm).

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33 (edited by geoarcher 2019-07-09 22:58:08)

Re: KTB Bamboo Arrow 5ea

ragnar wrote:

BTW, the rear section of my tong-ah, where the arrow rests, is 10mm wide (0,39"), the arrows are 5/16" (8mm).

My tong-ah is in another location not immediately accessible.  So I can't take measurements.  Recommend hunting down Saracen Archery as I'm pretty sure there were some specs in the section discussing tong-ah.  That's what I recall using pretty much exclusively to make mine.  You should be able to source that via the query I suggested.

BTW, its long been out of print.

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Re: KTB Bamboo Arrow 5ea

Well, almost there - with the third iteration.
The second one was made from a much larger diameter bamboo, almost suitable for shooting three arrows at once ...
While trying this version, I realized two other problems with my construction.
First, the holding string was fixed too far back, making it difficult to keep it on the right side of the string while loading.
Second,  the taper at the rear section was much too long, almost one quarter of the total length. The caused the arrow nock to be pressed down further against it, and lifted the tip up.

The third version has this issues resolved, with only slightly greater width as the first one.
I did some test shots in the garage, and it worked fine. Just need to shorten it for my draw length, and smooth it's surface properly.

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Re: KTB Bamboo Arrow 5ea

What I got from Bede's video was that when the arrow is installed it can't fall out so I guess it is somewhat enclosed up to half way down rather than equally open all the way along.
Good for you working it out.  I still haven't the nerve to try one of these things  smile

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Re: KTB Bamboo Arrow 5ea

Good for you working it out.  I still haven't the nerve to try one of these things


I used a low poundage bow for sure.
And my "family planning period" is over anyway ...  big_smile

What I got from Bede's video was that when the arrow is installed it can't fall out so I guess it is somewhat enclosed up to half way down rather than equally open all the way along.

The audio of the linke video was a bit hard to understand. But (as I assumed myself) if the tip rests down on the rail, the string is pushing it slightly inward when moving forward, keeping it from falling out.
I had a quite clear mental image of what could happen if I shot with the tip pointing out. Therefore all the fuss.

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Re: KTB Bamboo Arrow 5ea

ragnar wrote:

Good for you working it out.  I still haven't the nerve to try one of these things


I used a low poundage bow for sure.
And my "family planning period" is over anyway ...  big_smile

What I got from Bede's video was that when the arrow is installed it can't fall out so I guess it is somewhat enclosed up to half way down rather than equally open all the way along.

The audio of the linke video was a bit hard to understand. But (as I assumed myself) if the tip rests down on the rail, the string is pushing it slightly inward when moving forward, keeping it from falling out.
I had a quite clear mental image of what could happen if I shot with the tip pointing out. Therefore all the fuss.

Do you play the piano ?   lol

I know not all these tubes are the same & some may be more open but right at the beginning, when Bede inserts the arrow, he turns the device upside down & shows that the arrow can't fall out hence my assumption that when loaded the tip is partially encased already.  Of course the rest of the geometry must be correct but that aspect stood out for me.

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Re: KTB Bamboo Arrow 5ea

I know not all these tubes are the same & some may be more open but right at the beginning, when Bede inserts the arrow, he turns the device upside down & shows that the arrow can't fall out hence my assumption that when loaded the tip is partially encased already.

Can tell only from my understanding and little experience:
When you hold the arrow in with the index finger (as usually), the bow string rests on the rim, while the tip rests on the bottom of the rail (tong-ah). Thus, there is a slight "misalignment" between the force vector (the path the string moves, along the rim) and the axis of the arrow, slightly pointing inward, towards the bow. This small misalignment keeps the arrow in (pusing it in, towards the bottom of the rail) while the string pushes forward.
In mathematical therms F * sin(alpha)", where F is the force applied by the string, and alpha the deviation angle.

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Re: KTB Bamboo Arrow 5ea

I did some further test shooting during my holidays, and managed to bust my Nomad KTB in the process.
Just as Bluelake described in another thread (I think), the arrow slipped off the tongah rail on the upside, and hit the upper limb about two inches above the handle.
I can still feel my blood freeze when imagining it had slipped below. And 150 bucks squandered.
Anyway, I will put such experiments on hold, and not risking my tournament bows, and my physical integrity, of course.

BTW, I picked up some glassfiber staves from my longterm storage facility (parent's house).
Perhaps I make them into a crossbow during winter, time to re-use the "Pyeonjeon" arrows...

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40

Re: KTB Bamboo Arrow 5ea

ragnar wrote:

I did some further test shooting during my holidays, and managed to bust my Nomad KTB in the process.
Just as Bluelake described in another thread (I think), the arrow slipped off the tongah rail on the upside, and hit the upper limb about two inches above the handle.
I can still feel my blood freeze when imagining it had slipped below. And 150 bucks squandered.
Anyway, I will put such experiments on hold, and not risking my tournament bows, and my physical integrity, of course.

BTW, I picked up some glassfiber staves from my longterm storage facility (parent's house).
Perhaps I make them into a crossbow during winter, time to re-use the "Pyeonjeon" arrows...

That was bad luck. Lucky no injury yikes

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Re: KTB Bamboo Arrow 5ea

Lucky no injury

Definitely.
Albeit it seems due to the technique, the arrow almost alway jumps out above, to hit the bow. I don't want to take chances, though.
The replacement bow has already arrived.
The damaged bow still seemed to shoot quite nice. I think about fixing the hole with epoxy and giving it a try.

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Re: KTB Bamboo Arrow 5ea

ragnar wrote:

Lucky no injury

Definitely.
Albeit it seems due to the technique, the arrow almost alway jumps out above, to hit the bow. I don't want to take chances, though.
The replacement bow has already arrived.
The damaged bow still seemed to shoot quite nice. I think about fixing the hole with epoxy and giving it a try.

I've had success with major delaminations using G/Flex 650 Toughened Epoxy.  It's expensive but my repairs are still holding after hundreds of shots.  It's like alien technology  wink

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Re: KTB Bamboo Arrow 5ea

oni wrote:

I've had success with major delaminations using G/Flex 650 Toughened Epoxy.  It's expensive but my repairs are still holding after hundreds of shots.  It's like alien technology  wink

I will try. Albeit it's not quite a delamination (larger surface), more a cone-shaped hole, about 1/4 inch deep.
And brand names are different here. But normally, I use an epoxy with higher strength and longer curing times. The same one I use for the tapered tips on bamboo arrows.

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Re: KTB Bamboo Arrow 5ea

Since people on this thread seemed to have problems sourcing proper guidance on how to construct traditional Korean archery equipment, and since this thread had really to do with Korean arrows in the first place, I'm including this link here:

http://www.koreanarchery.org/classic/jookshi.html

I've never gone through all the steps myself but hope to one day.  Trick is always sourcing good bamboo to begin with which is about 60% of the battle.

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Re: KTB Bamboo Arrow 5ea

For archers in the US, river cane might be a good alternative.
It is not growing here in Europe.

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Re: KTB Bamboo Arrow 5ea

ragnar wrote:

For archers in the US, river cane might be a good alternative.
It is not growing here in Europe.

There's plenty of bamboo in the states.  Its actually easier to find rather than river cane.

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