Here’s a thread that will help some:

https://www.tradbow.com/members/cfmbb/messages.cfm?threadid=736A1B20-1422-1DE9-ED06A7419D523D48

The Update information on Internal Footings starts in the 2007 Updates, Part 2 or 3, I think.

Hope that helps,

Ed

Points 1 and 3 are correct. On point 2 it’s important to understand that there are two aspect to increasing integrity; direct impact and angular impact. Any footing increases integrity to direct impact, at least to some degree. The tough one was angular impacts. That’s where the gradually tapering back portion of the IF worked better than any parallel footing.

To the best of my knowledge no one manufactures a suitable IF. Several have tried with synthetic materials, but to no success. However, O.L. reported good success with a series of carbon tubes/rods as an IF. He used one tube that fit the shaft’s inside diameter, a second tube that fit inside that one and, finally, a carbon rod inside the second tube. The second tube was longer than the first and the rod longer than the second tube, creating a ‘step down’ taper. This IF was heavier than the hardwood IF’s I used but was easier to get precise weights with.

The Grizzly Stick was the toughest carbon shaft I tested.

I know of no one that has done further testing with the ultra-EFOC setups to determine the durability. I was only able to test the direct impact, and even that was very limited testing but with significant enough results to strongly suggest that the Ultra-EFOC setup was more durable to direct impact. Further testing was planed for the next round, but my back injury, and subsequent surgeries, has pretty much halted that plan.

Ed

Perhaps, ED, there are those here who would “volunteer” to do further impact and indirect impact testing under your watchful eye and control…:?:

Doc Nock wrote: Perhaps, ED, there are those here who would “volunteer” to do further impact and indirect impact testing under your watchful eye and control…:?:

I’ve been encouraging a few folks along those lines. Hardest part is gaining access to enough test animals.

Ed

Dr. Ed Ashby wrote:

I know of no one that has done further testing with the ultra-EFOC setups to determine the durability. I was only able to test the direct impact, and even that was very limited testing but with significant enough results to strongly suggest that the Ultra-EFOC setup was more durable to direct impact. Further testing was planed for the next round, but my back injury, and subsequent surgeries, has pretty much halted that plan.

Ed

My bad and my apology, Ed. I didn’t read closely enough. I thought you were speaking of impact resistance and THOUGHT (damn old age) that you and OL had done impact testing with the I.F. on hard surface impact—- so that others might do the same with glancing blows on hard surfaces to further test the I.F. 🙁 Sorry! To be honest, I thought you guys did glancing impact with the IF on some steel or something… doh!:oops:

As for animals, I cannot remember how many people would argue results from the penetration research by commenting that “yeah, if I ever want to hunt Aussie buffalo, that’d make sense“. Obviously only skimming your research and only those tests done on the Buf. Finding both quantity and suitable test animals, not long dead, would truly seem to complicate things!

I was really interested in the IF for some time, but lacking a shop or proper tools, hand-crafting a parabolic taper proved to be more challenge and then consistently replicating for a dozen arrows…well… 🙄

I did do a lot of ‘extreme punishment’ integrity testing of the IF’s (direct and oblique impacts) with shots against a piece of armor plate (the hatch cover from a personnel carrier) when I was trying to find the best IF setup but that’s still not the same as shooting heavy bone, where there are multiples of more complex curved surfaces ‘bouncing things around’. Best final testing is still fresh, in situ heavy bone.

Ed

Ah… Good to know my rememberer isn’t totally broken…so you did do the steel plate stuff… 🙂

I see your point that as the shaft is flexing around with the IF inside, going thru meat, it has to bend different ways and the meat resistance can cause other forces that might prove devastating while glancing off heavy bone!

Always interesting stuff, Ed. I wish you well finding someone to do more testing with the right controls. If anyone can coordinate it, you will be the one!

Still wish I could figure out how to generate consistent I.F.’s that would be controlled for weight and curvature.

Alas, hunting where I do, haven’t seen a bow range deer in 3 yrs…so guess what I got works well enough when it can be used!

Doc, How long until you heal up and are able to shoot/hunt/resume testing again? I see your work as a life’s work and a true legacy you are passing down to all in archery. I sure hope your research doesn’t stop here!

Jans

Ed– I second JP … and you need to get it all in a book as well!

I personally really like the external footings. I think it does wonders to strengthen a carbon arrow setup. It is also very versatile. You can make them as long as you want to really aid in tuning a heavy fronted weighted arrow without having to go to a stiffer shaft….just add a longer footing.

I do not leave home without it.

My entire shafts are footed. Hardwoods naturally footed. Some actually are very difficult to break. It took a couple years of trial and error though.

Kevin Forrester

forresterwoods wrote: My entire shafts are footed.

That was one of the conclusive findings of the Doc’s studies as I recall, that quality hardwood shafts had daylight between them and the best carbon shafts in terms of structural integrity.

Think I’ll test my 9/32 hardwoods in the holiday ham before cooking it. If the wife asks what happened, I was preparing the meat for garlic clove stuffing…