Hazel longbow, 100# @ 28"

[joachimM]

Slightly related topic for which I don't want open new thread.

Mmh, pretty confusing to have two completely different topics in the same thread... I was hoping to see the hazel bow, finally ;-)

This said, I don't bother too much about matching theoretical spine to a bow's poundage. What matters, IMO, is the acceleration an arrow experiences when it is launched. A 50# bow shooting an arrow at 150 fps will need a much lower spine than if it shoots the same arrow at 200 fps.

The general rule (500 spine for a 50# bow) likely comes from the fact that most normal (hunting) bows will shoot about the same speed (160-170 fps at 10 gpp), and shoot a certain grain per poundage arrows. In primitive bows, we tend to use 10 gpp as a standard for comparison, gf folks often use 9 gpp, and wheelies use 5 gpp...

You gotta find out what spine (or particular arrow) shoots best for each particular bow.

[FilipT]

I live in Croatia, there are no wild geese here. Nobody I know deals with poultry so I cannot get domestic geese and turkey, so the ebay. Same thing is with horns.

I bought heat gun today and tomorrow is judgement day. Either I will correct the string alignment and reflex or it will break.

[FilipT]

I managed to heat three areas on bow and correct it as far as I could. Also I removed slight twist from one limb. Now the offset from center is 6,5 mm which I think is manageable and will not rotate bow in my hand (or will it?). I couldn't get it more corrected as this bow had really resisted movement even when heated thoroughly. Below are before and after pictures. Red line represents string alignment.

BEFORE CORRECTION



AFTER CORRECTION

[Strichev]

Good, good. I'm following this.

[Hawkdancer]

Del,
I thought bow making is a religion!  It is certainly addictive!  And I am barely started!
Hawkdancer

[FilipT]

I cut the nocks but because of additional work around the house I cannot proceed to tillering for at least 2 days.

[FilipT]

I started tillering today. It was a big job, limbs barely moved for couple of inches. The biggest deal breaker is 40 mm of reflex. I cannot correct that. Also my tillering string stretches as even though I have string material (spectra fishing braid), I haven't got serving material so I didn't make proper tillering string.

Any suggestions?

[Strichev]

I find that if the string has too much twist it stretches more, spectra or not. Maybe that's the problem. Perhaps you could pre-stretch it by leaving a really heavy weight hanging  on it overnight?

[FilipT]

I don't even have a string made of it. My endless string jig is not finished yet and I don't have serving material. I am using currently a rope for starting engines such as those from lawn movers and chainsaws. It doesn't stretch really when you tiller a bow up to 60#.

[WillS]

If you've got good string material..... why not just make a string??  Endless loop strings aren't as good as twisted strings, and you don't need to serve twisted strings.

Make up a good strong twisted string with laid-in loops and start tillering.

[FilipT]

I would like to make regular flemish with bowyers knot but I hear many of these materials slip, especially slick material such as fishing braid.
Also, how would you deal with 40 mm of reflex and uneven shaped limbs (one has dog leg)?

[DC]

When I have reflex in a bow and it wants to flip on the tree I use 5 min epoxy and glue a flat piece on the belly side of the handle. It helps keep it stable. Once the bow is braced you just rasp it off.

[FilipT]

I doesn't flip at all and I am grateful for it! But what it makes is that it gives much more resistance to bending. I must try new string and see what it will happen then.

[FilipT]

I made the flemish string, it looks really good for a first try. It stretched a couple of times during tillering and than it stopped. Tomorrow I will continue with tillering.

[FilipT]

Bow is tillered to brace and ready for string!
Managed to get tips moving evenly to brace. I put the scale on rope and when the tips got to around 5-6" of draw (which is close to brace height), scale read around 100#. Since my scale goes to the 110# I didn't continue to measure further than that as it would break. 

When I put the bow on kitchen scale, its mass was 866 grams. In mass calculator bow with current parameters weighs about 842 grams for 130#.
So when I get these things into consideration, I think the bow is currently about 120-130#. Somebody (I think Del) said that when you measure draw weight using long string; what you measure at brace height, will be probably final weight when you put actual string and pull it to full draw.
Since I want bow around 90# I still got enough room for removing wood but as I have read about tillering heavy bows, I am aware that they can lose weight really quickly so I will not go furiously at scraping.

Now what I need help is that I don't know how to make stringer notch. I will simply need it as it will be impossible for me to brace this bow using usual stringer. Do I need to make just some shallow groove at the top of upper tip?