lever arm bow design advice needed

[stuckinthemud]

Hi All,

this is my prototype for my trade bow in the non-invitational trade but I thought I'd post a separate thread to get as wide a range of opinion as I can concerning the shape of the limbs. I am about to rough out the trade-bow proper, but want to make sure if I have properly dealt with the shape for a bow of this type - hollow limb, lever arm, sort of Molly but not a replica by any means.  Also should the limbs be equal length in a take-down; there is a 4" difference in the limb-length in this bow? Widest part of the limb is 2 1/4", levers are 8" long

[PEARL DRUMS]

That's no good.

[stuckinthemud]

Hi Pearl Drum, why is it no good? Need to get this as good as I can, need to know how to fix the design so the Trade is perfect. All advice very welcome

[PEARL DRUMS]

I gave all the advice I am going to. You don't listen.

[half eye]

Stuck,
     I dont believe that a sleeved takedown is any different than any rigid handled bow, except that the rigid bit may be longer in the sleeved version. As to the limb asymmetry the only bows I know about with a lot of it are the Japanese Yumi, or the Andaman Island paddle bows so cant help you there as I have never built either one.
    If you are speaking of a 3 piece takedown, I have never seen a commercial one that had diss-similar sized limbs....but again I have never built one of those either......sorry not much help.
rich

[stuckinthemud]

Hi Rich,

the limbs are asymmetric where once there was a handle which I ended up cutting in half, then cutting out, leaving the bottom limb shorter than the top :embarassed: although the tiller actually looked pretty good til I broke the string.........Anyhow, for the trade I think I will go with a rawhide and linen sleeved two part take-down but before I use these limbs for patterns I would like some feed-back as to what I need to change in their design, like I said, I really want to get this right

[ajooter]

I really think you should reconsider using this bow as your trade bow mud.  These are all great ideas to try...but on a different bow not being your trade bow.

I don't think a rawhide and linen sleeve would be strong enough to hold the bow together.  But you can always give it a shot.  Many people have been proven wrong on this site from time to time.  But you also have to consider the source and experience level of some of the people who have given you advice.

[PlanB]

Opinion offered, per request:

Stuck, I think you should concentrate on making a one piece bow with even length limbs and a conservative design for the trade. And start on that now.

And if you really have your heart set on an experiment with this other concept, just do it, outside of the trade. Experiments produce conclusions. Opinions never do.

End of opinion offered, per request

[stuckinthemud]

Hi Ajooter,

the rawhide sleeve was used on a lilac bow on paleoplanet (search rawhide scarf tube take down) on a bow stronger than my target weight so it should be OK. I am planning on building a longbow and a character bow, as well as a lever-arm,  as I have made several of those  but I want to persevere with the lever-arm until Whitsun.  I will choose the best to send in August.

Hi Plan B, my carrier (I am in the UK) will only take parcels up to 30" long so a take down is my preferred option otherwise I am looking at an international courier.  I figure I can make a strong reliable bow in the time remaining but will make sure one of the options is a one piece just in case.

[joachimM]

Nothing against a take-down, but I don't get the point of the asymmetry. 4" is a lot difference, and there should be a good reason to do so other than design constraints for a trade bow.
A trade bow is your signature, what you consider to be one of your own master pieces, not an idiosyncratic experiment that may or may not turn out OK. For a trade bow, you want more than just OK. 

And with this design, you risk ending up with much more set in the short limb, unless you darn well know how to tiller highly asymmetric bows.
Too risky IMO.

Joachim

[stuckinthemud]

Hi joachimM, this asymmetry is one of the things I am struggling with a little. So when I lay out a self bow, the arrow pass is just above half way along the length of the bow; the bow balances nicely on your index finger at half way, then there is a four inch handle (in a stiff handle design) so the lower limb is always 4 inches shorter than the top limb and a stiff handle self bow is always asymmetric with the tiller compensating by making one limb wider or thicker to compensate?
  the bow shown appears to be asymmetric but only because I started off with a self bow which ended up this way by accident. It was intended as a two piece but the project took me in a different direction as I mucked up the join as I specifically wanted to make a bolt together and did not want to use a sleeve, mostly to find out why bolt through take downs are so uncommon- guess I found out 

[---GUTSHOT--->]

Stuck I like that your going out on a limb and trying new stuff. I even tried making a bow I had a vision for and seeked help from Simon on it but decided to try it my way and my result was a broken bow. I feel a trade bow should be a bow you are good at making and just put some fancy into it. And make sure it shoots good and is safe. If I receive a bow in this trade that I feel is not safe after a good inspection I will not shoot it or string it. That's just my 2cents worth.

[stuckinthemud]

Hi Gutshot, love your Trade bow, so sorry about your wrist! My need to do this trade properly is why I post so much, guess I'm turning into a bit of a needy nag! I finish work for the summer May 20th, so I have the luxury of time to experiment and have checked with Fred if all is OK.  Since I do have time to build several bows and test them before the shipment date, I want one of them to be a Molly.  I had hoped this thread would not be about risers or sleeves but would be about the limb design I have been playing about with so I can change it and improve it for the 'real' bow - the one in the photo  is not for Trade in any way but to build my skills to do the Trade bow properly, so as far as a molly goes, what is right/wrong with the limb design: it seems to me that using a constant taper right out of the fades is not correct and I should have used constant width for a way?  Also, in a regular selfbow, the arrow pass is about an inch above halfway, but is this true for a molly?

[bushboy]

What type of wood do you have,lenght and draw weight?

[stuckinthemud]

Hazelnut, draw 28" weight between 40 and 50 at 28"