Author Topic: Sharp hooks ( a how to and lots of argument as to their merits )  (Read 31577 times)

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Offline PatM

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Re: Sharp hooks
« Reply #90 on: March 13, 2016, 03:37:43 pm »
Do you understand what I mean though?  Am I correct that you then drew the shorter version of the bow much farther relative to the new length?

Offline joachimM

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Re: Sharp hooks
« Reply #91 on: March 13, 2016, 04:00:15 pm »
PatM
Yes you're absolutely right. The recurves of the second bow didn't only lift off completely earlier, the bow was also strained more. So two things changed at once, while I should have limited it to a single change. No way I can disentangle the effect of these two changes now. that's why I mentioned "So just to make sure we agree on the setup:"
Next week. And I'll start another thread for that so Sleek will be freed of my design comments  O:)
 
Now, what I did show, is that it's a piece of caketo test this kind of questions: all you need is a heat gun, a chronograph or a smart phone with a chronograph app, and some PVC pipe. Oh, and a broad mind that acknowledges that PVC can be useful to primitive archery  >:D

So please folks, be my guest.

Offline PatM

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Re: Sharp hooks
« Reply #92 on: March 13, 2016, 04:21:20 pm »
   Hard to think of all the variables that can be changed, even accidentally. If you just use the same bow and back off the curves a little bit, brace height will then change unless the string is adjusted .

  I was thinking that a few sets of slip fit wooden recurves of the required degrees would be a good idea but who wants to make multiple sets and make sure the weight is identical   ???
 

Offline sleek

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Re: Sharp hooks
« Reply #93 on: March 13, 2016, 04:54:53 pm »
May as well keep it on here. It is what the thread has evolved to and its is related. My question was answered page one. I'm good.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline willie

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Re: Sharp hooks
« Reply #94 on: March 13, 2016, 05:10:15 pm »
An invitation for broad minds to bring some pvc creations? sound intriguing.

And a whole week before show and tell?

I think sleek just put more popcorn on the shopping  list..........

Offline bubby

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Re: Sharp hooks
« Reply #95 on: March 13, 2016, 05:26:57 pm »
If this devolves into a bunch of plastic bows it should be moved
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline PatM

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Re: Sharp hooks
« Reply #96 on: March 13, 2016, 05:36:50 pm »
   It's testing of mechanics! Nothing to do with the actual materials for bows. Remember Tim Baker's foam food tray mini bows? Same idea.

Offline scp

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Re: Sharp hooks
« Reply #97 on: March 13, 2016, 06:02:01 pm »
Next week. And I'll start another thread for that so Sleek will be freed of my design comments  O:)

What you did here is just wonderful, Thank you. Your contribution surely deserves its own thread. As for this thread, it is clear that Sleek got his answer early on. Time to sum up here, if I may.

The surest and easiest way to make "sharp hooks" is to boil the stave tips. But with enough skill, they can be made by steam and even dry heat, of course.

The issue of no liftoff is a read herring and moot, because nobody make such a bow or even saw one.

joachimM tried to show us that the "sharp hooks" need to be rather short to be effective. So far as I can tell, that is the opinion of most experts here anyway. We are not sure whether such a short recurve bow is no better than a straight bow or not.

Higher draw weight would account for the increased arrow speed therefore there is no advantage one way or the other

If we make the draw weight constant, not the draw length, the conclusion by joachimM might not be pertinent.

There seems to be a misunderstanding of what we were mainly trying to test here. It wasn't about big hooks versus small hooks, it was about degree of hook of the same length of recurve.
   Lift off versus no lift off.
   Are you sure you didn't  also draw the shorter bow further relative to length as well? It looks like it is being bent more.

Nobody makes a recurve bow with no liftoff. The issue might be which is better: earlier liftoff or later liftoff. And that question was only partially answered by the experiment of joachimM, as pointed out by Marc above.

As the original issue is how to make "sharp hooks" safely, PatM's question is somewhat more pertinent in this thread. The question is what would be the most useful "sharp" angle of recurved tips. Less than 90 degrees or even more than 90 degrees or 90 degree is simply the best? IMHO it would depend on the length of the recurved tips.

As for using PVC models for experiment, it does not bother me but if it does bother some members here, I think we can use bamboo strips. Most importantly, we need to agree on exactly what is the question that needs to be answered by the suggested experiment. I eagerly wait for more experiments by joachimM in his own threads with his own issues. I sure hope he does an experiment to answer the question of PatM. Thanks in advance.

Offline willie

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Re: Sharp hooks
« Reply #98 on: March 13, 2016, 06:20:57 pm »

Quote
I eagerly wait for more experiments by joachimM

Quote
So please folks, be my guest.

I thought all were invited to bring a model?, and I think your material of choice would be ok, Pat.

Offline sleek

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Re: Sharp hooks
« Reply #99 on: March 13, 2016, 06:32:18 pm »
Plastic models are fine with me. Why let our noses in the air to plastics over wood interrupt knowledge? If we so then we deserve to be uninformed. Let it happen here.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline PatM

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Re: Sharp hooks
« Reply #100 on: March 13, 2016, 07:12:57 pm »
scp, People have actually made no lift off recurves. Someone posted a yew recurve on here once that still had full contact at full draw.
 The Scythian bows also arguably had full draw contact.
 Maybe Bryce will chime in whether that bow he posted is in action yet. Seems like unless it was drawn ridiculously far it would also have contact.
   

Offline bubby

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Re: Sharp hooks
« Reply #101 on: March 13, 2016, 07:49:56 pm »
Plastic models are fine with me. Why let our noses in the air to plastics over wood interrupt knowledge? If we so then we deserve to be uninformed. Let it happen here.






There fine with me too sleek, just in around the campfire
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline PatM

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Re: Sharp hooks
« Reply #102 on: March 13, 2016, 07:59:49 pm »
I'm going to draw a few diagrams of theoretical angles and curves to try to illustrate how things will change accordingly.

  I will be using a piece of charcoal on Birch bark.

Offline sleek

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Re: Sharp hooks
« Reply #103 on: March 13, 2016, 08:25:04 pm »
Please.... do.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline PatM

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Re: Sharp hooks
« Reply #104 on: March 13, 2016, 08:45:26 pm »
 I'm all outta bark and charcoal and I won't stoop to the level of using a 2B and a sheet of printer paper on a primitive site. ;)