The perfect arrow

Paul Mattson · February 02, 2009, 02:41:00 PM

Did you have any nock end failures? When I did some testing, I would have the nock blow out and have a crack at the nock end. The point end was fine. I did my testing hitting cinder blocks or sheet of steel.

O.L. Adcock · February 02, 2009, 03:10:00 PM

Mike, you are right and I wish they would. Someone asked about extending the wood footing and tapering it, that would work but would still be weak right at the wood/shaft junction. What I have done is use carbon rod glued into carbon shafts then taper just as you would a wood arrow. Both nock and point. The problem with doing that up front is it's not heavy enough to get the FOC. At least with normal 125-160 grain heads. The 300's folks are coming out with would be dandy...but they don't make glue ons. Can't win for losing!

....O.L.

Paul Mattson · February 02, 2009, 03:11:00 PM

Mike,
I have the adapters. Made of brass to glue into a 5/16" carbon arrow and use glue on points. They come in wts from 75-125grns.

tradtusker · February 02, 2009, 03:47:00 PM

Ed have yo tired this on thin shafts like Beman MFX or Axis?

Littlefeather · February 02, 2009, 04:13:00 PM

Thanks for keeping us thinking and for taking the time to undergo and document all these things that I don't have the time or imagination to try myself. CK

Jason Jelinek · February 02, 2009, 04:35:00 PM

Does the same arrow without the internal footing fail on the same 45 degree and frontal shots? If so, do they fail on the first, 2nd, third, etc.?

What I'm getting at is there a measure of how much better the internal footing is compared to one without?

Good stuff!

Burnsie · February 02, 2009, 06:27:00 PM

ttt

O.L. Adcock · February 02, 2009, 07:12:00 PM

Jason; on the same armor plate test, without the IF's these same shaft setups fail first time, every time on both the frontal impact and the 45 degree impact. With just a parallel dowell (of the appropriaye length) they will stand up to the frontal impacts, but still won't hold up for a single 45 degree impact. The difference is night and day. Check out the shaft failure rates shown in the 2007 Update, part 2.

Andy, I haven't tried the IF's on Axis or Beman. Testing has been with Carbon Express, Gold Tip, Gold Tip UltraLite, etcetera .. the shafts with an ID of about 6mm.

As long as we're all 'wishing' I want a really well designed and constructed 250 and 300 grain GLUE_ON Broadhead and some STEEL inserts (in the same OAL's as the brass ones would be nice)!

Ed

Almost forgot; some of the nocks do occassionally pop off on the frontal impact hits, but I've have had no shaft cracks at the nock end.

Jason Jelinek · February 02, 2009, 08:11:00 PM

Thanks Ed!

Paul Mattson · February 03, 2009, 12:13:00 AM

Those are some very hard hits, if anyone is going to do some home testing. Besure to triple check the shaft after the shot, pay special attention to the nock end. If the nock blew out, it is very likely the shaft cracked. Also flex and bend the shafts, if you hear any thing, toss it. Carbons make a great arrow, they can also come out and bite you.
Be Safe!!!

Dave Bulla · February 03, 2009, 03:28:00 AM

O.L.,

What would happen if someone were to make a broadhead with a long, tapered shank that was a "glue in" instead of a glue on? No insert at all. Just a one piece head, shank & taper.

Picture a standard broadhead but solid, not hollow with a shank that was about 5 or 6 inches long, tapered like your wood dowel and maybe lightened internally at the aft end by drilling out the shank. I don't know what kind of weight you would end up with, but with no screw connection at all and a one piece steel head/shank, the strength would be incredible. I'm guessing the weight would have to be controlled by the blade and ferule thickness. Of course, there really wouldn't be a ferrule as the whole thing would be solid up in the head area but you know what I mean. Might have to go for more of a trade point style head and a mini ferule/transition taper to the shaft diameter to keep weight within limits but I'm not sure how heavy you want.

TomMcDonald · February 03, 2009, 05:00:00 AM

Someone with welding experience could easily do it.
I've got oxy but that'd be too hot.

I've got a friend with a mig welder.

Dave, I'll give it a go.

Don Miller · February 03, 2009, 08:17:00 AM

What's the best way to create the parabolic taper? freehand hints?

Thanks

dcolavito · February 03, 2009, 12:19:00 PM

Yep, I'm with you Don.......Anyone with freehand hints for the taper??

I'm guessing I'll need to get my hands on a drill press or something - ones I've seen seem mighty pricey, so any ideas there also appreciated.

And thanks again to O.L. and Dr. Ashby for this great stuff !!

O.L. Adcock · February 03, 2009, 01:01:00 PM

Don, I do my tapers freehand. I chuck the parallel portion of the IF in the drill press and work the taper down until I have the 'right flex'. The 'right flex' I'm looking for is best described as what you would see in a really good salmon rod - or a good bass-fishing 'worm rod'. I'm looking for there to be some flex full-length of the taper, but with more flex at the tip end of the taper. That's about the best I can describe it. I know what it looks like when I flex the IF by hand, but it's hard to quantify. Generally I end up with a slight weight veriation from IF to IF, but it is usually less than a 5 grain difference. That's a tolerance close enough that I sure can't tell any differnce when I shoot!

Dave, I see no reason why an 'IF self-shanked broadhead' wouldn't work just fine.

Ed

Dave Bulla · February 03, 2009, 02:31:00 PM

Just had another thought. Instead of a full inside diameter one piece steel shank tapered towards the end, I'm now picturing a setup like this.....

A broadhead with a standard length insert as an integral part of the shaft then out of the center of the insert would project a skinny rod of steel or maybe a piece of tungsten welding rod for about 5 inches. Then, make the normal internal footing out of wood and drill a hole in the wood to slip it over the pin shank of the broadhead.

Maybe I'm overthinking this as it's already proven that the wood insert as shown earlier works, but I'm thinking the integral head, insert shank and pin shank would transition forces from the 45 degree angle hits with no weak point at either ferule, screw or insert. The wood internal foot may very well have the best combination of strength and flexibility so my first idea of the all steel shank would probably be too rigid. With a pin shank, the diameter could be changed to control stiffness.

O.L. Adcock · February 03, 2009, 03:49:00 PM

There are a multitude of potential designs that might work. The first successful IF I came up with was the reverse of the ones described above. It worked beautifully, but was WAY to difficult to make by hand. Those IF's were parallel in their outside dimension, with a combimation of two internal parallel cavities (of differing diameter) and an internal conical cavity towards the terminal end. I also tried many, many other designs (without success) before finding one that worked. The only real way to find out with any of the design ideas is to build them up and try them!

Ed

SlowBowinMO · February 03, 2009, 04:06:00 PM

Very interesting information!
This split personality stuff between O.L. and Dr. Ed is giving me a headache though!

vtmtnman · February 03, 2009, 08:02:00 PM

QuoteOriginally posted by Dave Bulla:

A broadhead with a standard length insert as an integral part of the shaft then out of the center of the insert would project a skinny rod of steel or maybe a piece of tungsten welding rod for about 5 inches. Then, make the normal internal footing out of wood and drill a hole in the wood to slip it over the pin shank of the broadhead.

Excellent idea right there.

MrBok · February 03, 2009, 08:54:00 PM

O.L. thanks for sharing, sounds good.