My EFOC Woody Experiment

Jack Denbow · January 16, 2009, 03:18:00 PM

I have been intrigued by EFOC arrows. I like shooting and making wooden arrows rather than the modern faux

arrow material. It has been hard to get high FOC arrows with wood. Along comes Woody Weights and that worked pretty good. My first experiments with Woody Weights proved to me that I had to go up in spine with the addition of the weight up front.I normally shoot 55-60lb. spined arrow with a 145gr. point, but with the addition of a 125gr. Woody Weight I had to go up to 65-70lb. spine shafts. I just didn't like having 2 connections (point to Woody Weight and Woody Weight to shaft) on the front of my arrow. Somewhere I read about drilling a hole in the end of the shaft and filling it whith something heavy. I got a 3/16" steel rod and cut a piece 2 1/4" long and it weighed 123gr. I drilled a 3/16" (actually .004 larger to allow excess glue to excape) hole 2 1/4" deep in the end of a shaft.

and epoxied in the steel rod.

Then I did a second shaft.

I then finished the shafts and put the point taper on. I used a sanding disc on my table saw with a jig I made. I lost a little weight from the steel rod while doing the taper.

The finished tapered larch arrows weigh 715gr. They have a FOC of 18.4%, 1% less than with the Woody Weights. To me these are more esthetically pleasing.

It will be interesting to see how well this system holds up to my rugged abuse. Time will tell.
Jack

kadbow · January 16, 2009, 03:22:00 PM

They look good, how do they fly. I bet the answer is "good".

Jerry Wald · January 16, 2009, 03:26:00 PM

those look great..keep us posted on flight

jer Bear

Jack Denbow · January 16, 2009, 03:36:00 PM

I can shoot 15yds in the basement and have only shot the field point and it shoot great. I will try the broadhead when I get a chance.
Jack

Old York · January 16, 2009, 03:46:00 PM

Jack, that is neat!
NICE photos.
Orion has posted about drilling out the shafts too.

wtpops · January 16, 2009, 03:51:00 PM

Sounds like it might reinforce the tip like footing a carbon

Izzy · January 16, 2009, 03:58:00 PM

That looks real good.

jonsimoneau · January 16, 2009, 04:03:00 PM

That is awesome! I'm going to try something to that effect also. Only difference is I'm going to start out with some Sitka spruce. They are light. Going to get them spined really heavy and possibly footed. Then add a bunch of weight up front until they fly right.

Brian P. · January 16, 2009, 04:13:00 PM

Same set up I use to gain weight on wood shafts. I use 1/8" brass rod instead. The brass is actually heavier than same sized steel rod in my experience.
With 1/8" rod, you dont grind into it during the tapering process. At least I dont with my tapering set up. I havent done any in a while, but I seem to remember a 2" piece of 1/8" brass rod weighed 60-70 gr.

BP

jonsimoneau · January 16, 2009, 04:15:00 PM

Did you make up some sort of jig to drill that? Seems like the steel would have to be centered in there perfectly or there would be bad flight. Maybe I am wrong on that though.

Dan'l · January 16, 2009, 04:17:00 PM

Jacques, They look great. It'll be interesting to see how the broadhead arra works on hogs. Regards,

Jack Denbow · January 16, 2009, 05:01:00 PM

Jon I used a lathe, but even at that I screwed up one shaft with the hole going at an angle. After that I used a heavy starter bit and a small bit then up to the 3/16". Drilling in the end grain is tough because of the hardness and softness of the alternating grain.
Jack

Orion · January 16, 2009, 05:07:00 PM

You probably read about it on here. It's in a few threads, including some of the Ashby stuff on high FOC arrows. O.L., I and others have been doing it for a while. Works good. I'm working on getting a machinist to make a jig for me to ensure exact centering of the drill hole. So far, my experience has been tht they're pretty durable. The metal rod sticking into the arrow further than the broadhead taper strengthens the area immediately behind the broadhead. May just move the weak spot to the back of the metal insert though.

We are sort of reinventing the wheel here. Folks were drilling out their shafts and inserting lengths of nails back in the 60s. Didn't know much about FOC then, but we did know our arrows seemed to pack more punch when constructed that way.

WESTBROOK · January 16, 2009, 06:38:00 PM

Nice job Jack!

I keep hearing of table saw rigs for doing tapers, is there a disk you can buy to stick your discs to?

Eric

O.L. Adcock · January 16, 2009, 06:57:00 PM

Good job Jack!

Eric, you can get 10" steel disks that replace the blade. I made a jig out of 1/8" ply I clamp to the table saw with a wood fence at 6 degrees on one end and 11 on the other. Works wonderful to taper nocks and points....O.L.

Jack Denbow · January 16, 2009, 08:21:00 PM

I get my discs from Woodworkers Supply. I have to cut a hole in them for the arbor. I think I got the steel disc at Sears since it is a Sears saw. The jig I use I made form pictures in one of the early TBM's. I have been using it for nearly 20 years.
Jack

WESTBROOK · January 16, 2009, 09:11:00 PM

O.L., Jack, I'll be lookin' for one, Thanks!

Eric

O.L. Adcock · January 16, 2009, 11:46:00 PM

I think I got mine at Sears also and it was ready to go.....O.L.

Dave2old · January 17, 2009, 10:56:00 AM

O.L. also uses tungsten rod inserts, which have the double advantage of being much heavier than steel, yet very strong so you can use smaller diameter to get the weight you want and not have to deal with tapering the metal insert. Him one clever feller!

BMG · January 17, 2009, 11:15:00 AM

Food for thought:
If the metal insert gets epoxied to the metal broadhead the energy of an impact will be much more direct transfer of energy onto the wood. I would think that an off angle shot (shoulders, ribs, stumps) would splinter the arrow very quickly, the angle of the hit would transfer that energy towards the wood shaft and I'm wondering if the wood could resist that sort of kinetic energy of a heavier arrow?