Trad Gang
Main Boards => PowWow => Topic started by: O.L. Adcock on February 01, 2009, 10:53:00 PM
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Much has been written lately about FOC, footing arrows, tuning, Ect....Several manufactures have been playing with potential ways to easily and cheaply foot arrows without much success. With Doc Ashby we've been playing with a method that works very well.
A few things we're looking for in an arrow. One is high FOC. Another is structural integrity. Many of the ways folks have been footing shafts is external sleeves. They no doubt help but increasing the shaft diameter is not ideal plus all it's doing is moving the weak spot behind the insert further down the shaft. Internal tubing, wood, fiberglass, ect...Again moves the weak spot to another spot. They may be better but not ideal.
Here are the parts: (http://www.bowmaker.net/images/footing.jpg)
Start with your shafts and brass inserts the weight you want. Aluminum inserts in a frontal hit can mushroom and deform. Brass is not as prone to do that.
The footing....Is 1/4" oak dowel you can get at most hardware stores. Make it about 7" long. The front 3" needs to fit your shafts perfectly inside. If too big it can be chucked up in a drill and sanded and doing so in a drill press with a sanding block works very well.
The remaining taper to about 1/8" in a parabolic taper, not a straight taper. Only the front 3" is glued in the shaft. What the parabolic taper does is as the shaft begins to bend from a hard angled hit, the shaft begins to contact the footing, the more it bends, the more contact is made. This spreads out the forces over a distance over time totally eliminating the typical weak spot behind inserts and other footing methods.
3" is the minimum for the parallel front section. This will keep from shoving the insert/footing back into the shaft on solid frontal hits. More then 3" could be used and more then 7" total length, just depends on if you want to increase spine and or get more weight up front.
Rough up the inside 4-5" of the shafts and swab out the dust. Smear epoxy on the 3" parallel part of the footing, slide it in almost flush with the shaft end. Slobber up the insert with epoxy and use it to push the footing into the shaft. If you push the footing in aways before the insert, you'll have an air pocket that will just push the footing too deep and leave a gap. At this time set it aside point down to cure.
Oak works well, I'm sure other woods and other materials like fiberglass or carbon will work just as well, maybe better. The oak inserts will weight about 60 grains and it's a good idea to adjust them so they are all the same. Carbon would be about 160 grains and glass a bit more.
With this footing, 100 grain inserts, 125 adapters, and 160+ grain heads, we're getting FOC's upwards of 25-30%. We've put brass, steel, or tungsten slugs, 1-2" long between the insert and the footing for some serious FOC. This also works with aluminum arrows. The 7" footing does not change the static spine but footings with longer parallel sections will.
Don't ask for "recipes" for given arrow/bow combinations, there are just too many possiblities. Have fun! :) ....O.L.
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Some awesome wisdom here.....thanks for passing it along O.L. !!!
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THat is interesting for sure! I am very happy with my external aluminum footing...its still smaller than the ferrule of my griz or snuffer... and I never get failures...
However..I will surely try this! :0)
Ernie
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MORE good info.! Looks like I might be retuning arrows since going to the skinny string. This might be a good time to try this.
Thank you Mr. Adcock and Dr. Ashby!
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It sure makes them bullet proof and it appears they are a good bit quieter in flight also. We're still chewing on that one and how to take it one step further...O.L.
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Nice! Thanks for sharing this with us, O.L.
Allan
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Question, If Your footing it with wood, Could you have the wood stick out 1" +/- to hold a glue-on point?
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shaft makers are going to have to start making super light, super stiff shafts to keep up. especially in heavy # bows which is where this idea of footing is worth while. try finding a shaft that is going to handle 500-600grs upfront out of an 80# bow
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O.L. how do you glue the insert?
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Sal, that's the same thing as putting a foreshaft on a cane arrow... I don't see why it wouldn't work, but I think you'd want a pretty solid ridge butting up against the shaft to prevent the footing from just being pushed into the arrow.
Sure would make it easy to mount a stone head on carbon or aluminum arrows :)
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OL how much does the 3 inch parallel section change the spine of the arrow?
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O.L.: You keep this up and you're going to make me want to change to carbon arrows. :thumbsup:
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nice, i like it!
thanks for sharing
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Do you get a weak point at the brass insert / wood insert butt joint? Looks unbreakable except for possibly that spot.
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Originally posted by Jeremy:
Sal, that's the same thing as putting a foreshaft on a cane arrow... I don't see why it wouldn't work, but I think you'd want a pretty solid ridge butting up against the shaft to prevent the footing from just being pushed into the arrow.
Sure would make it easy to mount a stone head on carbon or aluminum arrows :)
Jeremy, that's where I got the idea, plus I fixed some arrows adding a small piece of 2315 easton shaft with a small piece of dowel to glue points on to so I could still use my broken arrows that where just a little to short/stiff for my bow... It worked great and gave a nice FOC and fix the spine of the arrow to make it weaker.
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Hi O.L.
Many thanks to you, Dr. Ashby and any others who've worked on this - very helpful info !!!!
Much obliged for any recommendations on the following:
1. Technic to achieve "parbolic" taper?
2. Fit tolerance between dowel O.D. and shaft I.D.? 1mil, 3mils, 5mils, etc...?
- I ask b/c "The front 3" needs to fit your shafts perfectly inside", and wonder whether it's a concern that too tight a fit may not permit sufficient epoxy between them. Also, when is the gap betwen them considered too large?
3. I'm thinking it's best to begin tuning with these I.F.s already installed.
- For those already tuned, would they need to re-tune (can't hurt, but wonder how necessary).
Dave :thumbsup:
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Originally posted by O.L. Adcock:
The 7" footing does not change the static spine
Dave, assuming this is true (fairly safe assumption ;) ) you can get your chosen shafts close to tuned, then do the internal footing and the final tuning adjustments with point weight. Makes sense to me anyway.
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O.L. how much does the 7" sanded 1/4" dowel weigh by itself?
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Okay, since O.L. has this going, I'm just borrowing his handle. Here are a few photos that might help. Also, in order to stand up on direct frontal impact (and avoid set-back) the critical glue attachment surface area is a total of 3"; that includes the brass insert and the parallel portion of the IF. On my IF's (behind a 100 grain brass insert) I use a 2" parallel glue-attached section of the IF, then parabolic-taper the terminal 5" (on a 7" OAL IF).
Photo 1 - 5" IF; 100 grain brass insert.
(http://i141.photobucket.com/albums/r53/ed_ashby/2008_0529Download0001_2.jpg)
Photo 2 - 10" IF; 100 grain brass insert.
(http://i141.photobucket.com/albums/r53/ed_ashby/2008_0529Download0004_2.jpg)
Photo 3 - With a properly designed and installed IF, at the worst this is all that happens with a direct impact. This shot was with the 82#@27" longbow into a 1/2" thick piece of armor plate (it's the hatch cover from an armored personnel carrier) from 20 yards. The arrow withstood 3 hits before the point bounced loose, moving forward (the field point was changed after each impact). Note that the shaft in undamaged. The IF suffered no set-back.
(http://i141.photobucket.com/albums/r53/ed_ashby/2008_0623Download0060.jpg)
Photo 4 - This shows the flattening on the 190 grain field point that occurred on each hit.
(http://i141.photobucket.com/albums/r53/ed_ashby/Copyof2008_0623Download0057.jpg)
Photo 5 - This shaft crack occurred on the 4th 45 degree angular impact. There was no damage on the first three shots. Note that the crack stops where the IF starts. The IF was not set-back any. See what finally did give in the next photos!
(http://i141.photobucket.com/albums/r53/ed_ashby/2008_0623Download0067.jpg)
Photo 6 - On the forth 45 degree angular impact the brass insert and steel adaptor bent! The 190 grain field point was changed after each shot. Why? See the next photo.
(http://i141.photobucket.com/albums/r53/ed_ashby/2008_0623Download0069.jpg)
Photo 7 - On each angular impact the field point's tip was flattened along the 45 degree angle of impact.
(http://i141.photobucket.com/albums/r53/ed_ashby/2008_0623Download0070.jpg)
More photos in a moment.
Ed
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Here's the rest.
Photo 8. 9 & 10 - many exotic materials were tried, from several grades of aircraft aluminum to carbon/fiberglass composite materials, but nothing (so far) has worked as consistently well as the hardwood IF's.
(http://i141.photobucket.com/albums/r53/ed_ashby/BrokenIF_2.jpg)
(http://i141.photobucket.com/albums/r53/ed_ashby/IFProto2bend_1.jpg)
(http://i141.photobucket.com/albums/r53/ed_ashby/IFProto2firstshotdamage.jpg)
Photo 11 - My "Top Secret Weapon" for IF instillation. A popsicle stick is whittled down to a loose fit inside the shaft. It is carved just long enough to reach to the rear end of the IF's parallel glue-attached portion. Slow cure epoxy is used. After the parts are surface roughened, cleaned and glue-ready the inner wall of the shaft is lightly coated with epoxy. Then the portion of the IF to be attached is coated with epoxy. Holding the shaft vertically, the IF is inserted until flush with the shaft. The insert is then coated with epoxy and used to push the IF the rest of the way into the shaft.
Lightly coating the shaft's inner wall before inserting the IF causes the IF to push a ring of epoxy ahead as it is inserted. By using slow cure epoxy and storing the shaft vertically until the epoxy sets, a small ring of epoxy is depositied immediately back of the parallel, glue-attached portion of the IF. This adds significant reinforcement to prevent any back-set of the IF on impact. If you longitudinally section an IF shaft, this glue ring is clearly visible - and if you flex the sectioned shaft you'll be able to watch the IF at work, as it would be on an angular impact; spreading the obliquely applied force along a very long section of the shaft's inner surface.
The best epoxy I've founbd so far is Selly's Maximum Hold, which has over an hour's work time and a 3 day 'fully curred' time, but I'm not sure it is available in the States.
(http://i141.photobucket.com/albums/r53/ed_ashby/2009_0203Download0004_2.jpg)
Ed
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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.
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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.
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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.
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Ed have yo tired this on thin shafts like Beman MFX or Axis?
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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
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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!
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ttt
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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.
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Thanks Ed!
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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!!!
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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.
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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.
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What's the best way to create the parabolic taper? freehand hints?
Thanks
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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 !!
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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
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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.
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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
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Very interesting information!
This split personality stuff between O.L. and Dr. Ed is giving me a headache though! :smileystooges:
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Originally 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. :thumbsup:
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O.L. thanks for sharing, sounds good.
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How long would the parrarel section of the Footing need to be before it starts to change the spine of the arrow? Would it change the static spine at all? or is too close to the end to make a difference?
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I Like It! KY
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Excellent post O.L.
I'll be attempting to tune my first arrows this weekend and they happen to be carbon. I have NO idea where to start... HA! :smileystooges:
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great info,thankyou
pat
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I have been doing the outside footing and it does make it stronger, but it also just moves the weak spot as I broke shafts right at or just behind the footing
Thanks for more things to test
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Dave
OL talked about that in he's first post. but it looks like a lot of work to save a arrow. Not to blow my horn, but I just don't miss that much any more. :)
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Redant,
I went back and read O.L.'s first post and don't see anything like what I'm talking about mentioned. He talks about internal and external tubes and adding slugs of various materials (including tungsten) between the insert and the dowell but nothing like what I'm thinking.
I'll see if I can't draw it up on paper and either scan it or take a pic and put it in the thread.
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Very interesting stuff. I wonder if this can be adapted to a full taper arrow like the Arrow Dynamics.
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Yes, very interesting stuff but I wonder if I can make it work with my Easton ST Axis shafts? They are real skinny to begin with and using a dowel that skinny may not add that much FOC.
O.L., is this better than the brass tubing method you wrote about last year? I have found tubing for my Axis shafts just have not got around to trying it yet.
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M60, Oh yes, much easier and works as good if not better. Not doing this for FOC but it does help, doing strictly for durability. A fellow can do more with brass, steel, or tungsten for the FOC thing. Skinny shafts like ST's, better to make the footing out of carbon rod. The Doc should be posting some photos soon of a cutway shaft.
DeadSmple, if it's hollow it'll work.
Dave, what you're thinking would work great IF you get it long enough and bendy enough to spread out the forces and it doesn't weigh 2000 grains! Doing these in steel would be very heavy, the steel would be too stiff, and the machining process too expensive. Some manufactures have played with this, materials cheap and easy to mold are too soft and don't work, and anything requiring machining or turning just way too expensive....O.L.
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Fantastic, I've been waiting for this. Thanks for sharing, its great information!!
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What about filling the front end of the arrow with caulking or silicone or something alittle more rubberized for weight.
You could tell how far into the shaft the filling was going by weighing it as you fill it. Maybe practice on some busted shafts. Cut them to see how far the filling went in. Then put the insert in. I would think it would make the shaft stronger from the inside out.
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"What about filling the front end of the arrow with caulking or silicone or something alittle more rubberized for weight."
That would add weight but wouldn't stop inserts being shoved into the shaft or breaking behind the insert on angled shots....O.L.
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O.L.,
I've just figured it out! Hee hee.... kinda.
Lone archers post did the trick. You need to find a way to make JB weld foam up! Like expanding window insulation. Squirt about two inches of "expando-weld" in behind the head and stand the arrow up vertically with the point down. The trick is to get the JB to stay solid for about the first inch and expand about 4 more inches up the shaft with more and more "foam" as you get to the top of the column. More foam equals less density and more flex with gradually decreasing weight and stiffness from point to end of the "foot".
Well, I'm being kinda a smart alec about it with the JB comments but if you could come up with something that would seperate in layers or naturally change density between solid at the front and soft at the rear it would work I think.
Now just run along and invent it eh?. :)
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OL: Good to see you out and about!
I think the Buffalo arrows Karen and I used two years ago did this well. We used Gold Tip big game 100s, and assembled a front end insert that began with the stos head and 125 grain adapter, then the arrow insert and 200 grains of brass weights, then a 15 inch carbon piece that reached to the midpoint of the arrow. With roughing of all surfaces and cleaning with detergent, then alcohol, and leaving surfaces wet, I then swabbed the entire inside surface of the arrow with gorilla glue (it is chemically activated and cured by water), then pushed in the carbon insert with the head assembly, and let cure point down with a boot over the fletched end.
Those arrows were (and are) bomb proof. FOC 24%. Weight 1020 grains, but that formula can be made to work with light arrows as well. Took two buffalo, one arrow kills.
I tried wood inserts, but the work to sand and the variable weight bothered me. Hope this helps. - Jay Campbell, JD
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Now that I go back over my math, those carbon shaft inserts were 12.5", not 15". Designed to reach midpoint. - Jay Campbell, JD
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Hey Jay, no doubt lots of ways to skin the cat! :) The gorilla glue would retain some flexable properties. Your carbon insert is great but you'll find shaft sizes with no "off the shelf" carbon rod size will fit, we're back to sanding and grinding and weight variations. Take that arrow and get an angled ball joint hit, or a rock out stumping, you've still got a weak spot at the end of that rod, you just haven't exceeded it yet! :) Plus a lot of mass. Try getting high FOC's and tough arrows to come in at 500-600 grains, that's the hard part....O.L.
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Can anyone suggest a good epoxy that is accessable in the U.S.?
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G2 is pretty good, used for bow making, but it's strong and flexible.
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O.L i don't know what your wood arrow description did for Dave.but my arrow building ideas are going thanks .I'm gonna try these carbon ideas too.
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For an adhesive alternative to epoxy, I can vouch for gorilla glue as a great product for these kinds of carbon arrow laminations. It expands to fill all gaps, remains flexible, holds in temperature extremes, and is extremely tough. Also, in closed in spaces like arrow shafts, some air-dry products can't cure properly. Gorilla glue doesn't require air. - Jay Campbell, JD
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I built an arrow similar to this method because I've got an extremely long draw and I can't find a readily available shaft stiff enough to tune out of my 60# bow.
I shoot a full legth 32 3/4" 340 spine arrow with standard aluminum insert and 125 grain point from my 50# at 32" draw A&H ACS CX and Centaur bows.
I just made up a batch of four with the following ingredients:
- Axis 300 black shaft, full length
- Beman Carbon Flash shaft 3" internal footing behind the insert
- Easton 2018 external footing 2.5" long
- Standard Aluminum Insert. Might try the new 50/75 grain Easton brass insert or a 100 grain brass insert in my next four arrows if I need more weight to tune.
- Golf Works Epoxy 24 hour cure/flexible
The gluing method is similar to described in this thread.
With the HIT insert the 3" internal carbon footing is just under 5" into the arrow shaft and I will make the IF longer or shorter depending on how the arrow bareshaft tunes with my desired weight of point. The 2.5" external footing covers the entire insert and 1/2" of the internal footing so the weak point is moved back nearly 5" from the point.
I believe an external footing is a must with the HIT insert shafts since the area between the insert and the point is the weakest spot on the arrow in my experience.
I also "foot" the nock end with a 3/8" long piece of the 2018 shaft. This prevents nock damaged to the nock end of the shaft.
After reading this thread I hope the Beman Carbon Flash IF is a little flexible so the front of the arrow will bend a little bit. I might try the tapered hardwood IF method described in this thread if my method doesn't work out.
This arrow weighs 620 grains with a 175 grain head. I haven't shot the combination but I'm hoping for good results. I'll post pics on this thread with an update in a few days after I have some time to test it.
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Sorry but I just have to ask... :)
.What do you guys shoot with arrows that makes them need all these footings? I understand wanting a durable arrow but you guys must be bounceing arrows off tanks or something. :D
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James, I've had arrows break behind the heads on "elbow" shots and you can not shoot an arrow in this country without hitting a rock. You can say "don't hit elbows" or shoulder blades but if it hasn't happened to you yet, it will! :) ....O.L.
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OL I guess my girly weight bows probably don't have enough punch to break my arrows anyway. :bigsmyl: I might make up an arrow for the toughman shoots like you guys however.I have crippled a few on the steel targets before and I think the ones some of you are making might be great for that. thanks
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O.L. promised I'd post some cutaway photos of the IF's, so here they are. My apologies for the delay, but my back is still not 100% functional - still slows me down a tad!
Photo 1 shows the full IF in place, back of the brass insert. Note that the cutaway shown does NOT go to the center-line of the shaft. When the shaft is flexed to show how the IF works, everything tends to break lose from the shaft's wall if the cutaway is made to the center-line.
(http://i141.photobucket.com/albums/r53/ed_ashby/IFCutaway001_2PB.jpg)
Photo 2 is a closup of the IF/insert junction. They are epoxied together, but keep the glue joint very thin. In testing, the thin junction worked better than a thicker junction.
(http://i141.photobucket.com/albums/r53/ed_ashby/IFCutaway002_2PB.jpg)
Photo 3; The red arrow shows the 'glue dam wedge' that is created nack of the IF's parallel (glue attached) section. As I explained earlier, this is acomplished by applying epoxy to the shaft's inner wall (to the depth of the IF's glue attached segment) prior to inserting the IF. This is an important step in obtaining maximum direct-impact strength. (The glue-attachment section of the IF is also coated with epoxy prior to insertion in the shaft.) Insertion of the IF into the shaft pushes a ring of the excess epoxy on the shaft's inner wall up into the shaft. By using a very slow-cure epoxy, and storing the assembled shaft vertically until the epoxy is fully cured, the epoxy forms the glue ring; immediately back of the IF's parallel segment.
Even though the cutaway is not to the shaft's center line, note clearance between the IF's tapered section and the shaft's inner wall (green arrow).
(http://i141.photobucket.com/albums/r53/ed_ashby/IFCutaway001_2_1PB.jpg)
Photo 4 shows the terminal end of the IF.
(http://i141.photobucket.com/albums/r53/ed_ashby/IFCutaway003_2PB.jpg)
Photos 5 and 6 show the shaft flexed against the terminal end of the IF. Remember that the IF also has a graduated dgree of flexion, "like a good salmon rod". with the cutaway shaft I can't achieve enough shaft pressure against the IF to make the IF flex, something easily done when the shaft is intact.
(http://i141.photobucket.com/albums/r53/ed_ashby/IFCutaway005_2PB.jpg)
(http://i141.photobucket.com/albums/r53/ed_ashby/IFCutaway004_2PB.jpg)
Ed
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I am impressed again with the attention to detail and testing. Thanks for so freely sharing the info!
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Nice.
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First off, both of you are nutts (Doc. & OL) and I love ya for it, did you guys blow up the garage with your chemistry sets as a kid lol.
Just when I think I got something good cooked up, you two go and raise the bar again, you two are great.
Now the shafts I am using are vary small internally, I have used 7"x 1/4" steel cable for EFOC with amazing results, it fits nice and tight.
so, for these shafts, what could I use to do this IF thing on them.
Thanks
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Dave, Dave you have to much time on your hands, time to go back to work. :bigsmyl: :cool:
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thats preety cool
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Got another question, what if you put say 5" of aluminum shaft over the front of a carbon shaft and you put 4 cuts down the aluminum footing like a + sign, so it had some give, say 2 cuts 1" and 2 cuts 2" long.
Does this sound to crazy.
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King, I was doing that internal with brass tubes. It worked but was a PIA! :)
The tiny shafts, bet they aren't smaller then some of my flight arrows, less then .125"ID so sure, it'll work. Carbon rod would probably work best. Do a search for Aerospace Composite Products, (ACP)...They have carbon rod and tubes of many sizes. Another trick, glue 1"-1 1/2" of carbon rod in the back of a carbon shaft, taper it on a disk sander just like a wood arrow and glue nocks on. Works great and lighter then the aluminum nock inserts....O.L.
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OL,
At the start of this thread you wrote:
3" is the minimum for the parallel front section. This will keep from shoving the insert/footing back into the shaft on solid frontal hits. More then 3" could be used and more then 7" total length, just depends on if you want to increase spine and or get more weight up front.
Did you find through your testing that 3" of parallel front section had little to no effect on the dynamic spine?
The reason I ask is because on an earlier post I added on this thread I discussed trying a similar method with an Axis shaft and a 3" carbon IF. This arrow shoots very similar to the same arrow without the IF. I'm thinking I need to lenghten the IF to 5" and give that a try because I'm getting a 3" left tear with both shafts when paper tuning. When I get closer via via paper tuning with different shaft/IF combo's I'll bare shaft tune but paper tuning is the best I can do right now given the short days, my work schedule and the fact I'm not home during daylight hours and can't shoot outside.
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BTW - Once I'm close on the correct parallel section length I'm going to try to taper the carbon IF similar to the wood dowel as described at the start of this thread. I'm not able to find a wood dowel that's small enough for the Axis and I thought I was stuck with the Beman Carbon Flash shaft for an IF but after seeing OL's post about the ACP composites company I found some better alternatives. I might also try cutting the last four inches of the IF in fourths, too, as previously mentioned a couple posts up.
...Or change shafts to a Gold Tip or standard Easton and use your method. That could prove cheaper and easier!
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Scott, 3" with 7 1/2" total length is as far as I've gone so far and it doesn't seem to change the spine much. Logic dictates it has to make it stiffer but the added weight may off set it. Carbon would be more then double the weight but stiffer also. It's hard to take well tuned "normal" arrows then do this and draw any conclusions, just too many things changed. Got some hunter super carbons that static spine 60# and only weigh 200 grains for a 29" shaft. I bet they'll come in at 25% but only weigh about 525gr. Perfect for the lighter bows....O.L.
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OL,
The only thing I can figure is the front 3" to 4" of the arrow doesn't flex much anyway so that plus the weight may result in the effective spine staying about the same. I love the idea you and the doc developed and trying to get it to work on an Axis shaft is sorta fun.
I ordered some .196 diameter carbon tubes from ACP composites tonight. These are slightly bigger than the Carbon Flash shafts which are .1815 and slightly smaller than the brass Axis insert at .202 but with some heavy epoxy they should work okay. I'm thinking the carbon rods are a bit too heavy and would be difficult to taper (cutting in fourths might work) plus the closest size is .186 which might be a little loose but I ordered one of those just in case I want to experiment.
I'm going to try to cut the tubes to 9" in length and then cut the back 4" in fourths. That'll give me a 5" parallel section to stiffen spine and 4" of shock absorbing material. I hoping the 4" section cut in thirds will help absorb impact shock similar to your tapered shaft design. If I can get this arrow to tune I'll report back the results in a few weeks and hopefully I don't get lung cancer from all this carbon dust I'm going to produce!
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O.L. thanks for all the great ideas.
I have a question on the oak dowels. Most that I've seen are poor quality and usually warped. Are you truing them up with the sanding, or have you just selected those that appear to be straight? Also, how snug should that first 3" fit? Thanks,
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Str8, Yep, got to pick through them. I cut them to length then chuck them up in a drill press. I use a flat metal sanding plate called "Permagrit". They come in various grits and are tungsten carbide embedded on steel and last for tens of years under heavy use but sanding blocks with 50 grit or some rasps would work also.
I do the parallel section first using a cut off piece of shaft to check fit, then I flip it over and do the taper. I weigh them to find the lightest then touch up the heavier ones till they match. Takes about 45 minuets to do a dozen. Others may find faster or better ways. Perfect straighness isn't needed since it only comes into play thumping something hard.
Tilzbow, Sounds like that'll work! :) Carbon is a little tougher to work with but not much. Just don't be shy with the sand paper or rasp, 36 grit is your friend!....O.L.
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This is fun stuff. And amazing. If someone said make me an arrow shaft that can be shot into a solid steel plate and not break, I would have said impossible, especially with EFOC. Wow.
So my question is, "where does all the impact energy get dissipated?" The force on that arrow at impact is huge. The wood must get hot.
You know an interesting thought is the IF is really the arrow and the "traditional" (funny using that word here) arrow shaft is just the launch or guidance vehicle - at least at impact. Maybe that is why it doesn't break (as much).
Thanks for sharing.
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O.L./Dr. Ashby
Regarding the parallel taper length, 2" vs. 3" ? Does it make much difference?
Unless I'm confusing things:
O.L. has been referring to 3" of parallel taper on the IF, whereas earlier in the thread Dr. Ashby was referring to 2"......
"the critical glue attachment surface area is a total of 3"; that includes the brass insert and the parallel portion of the IF. On my IF's (behind a 100 grain brass insert) I use a 2" parallel glue-attached section of the IF, then parabolic-taper the terminal 5" (on a 7" OAL IF)."
Thanks !!
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Sorry this may be an obvious question, but when storing the arrow vertically to provide the glue ring...is this point end up to allow the glue to flow down providing a gradual taper or down, so the epoxy pools against the parallel section of the IF?
Again some fantastic information here, thank you for sharing!
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It-m-grow, most is still being asorbed by the arrow but in a way that doesn't cause damage. The difference between diagonal cutters as opposed to wide jawed pliers, a lot of force in a small area as opposed to large.
dcolavito, It's a question of how much is enough> Ed has had good results with 2" and a glue dam and I with 3" and no dam...We'd know what isn't enough, it'd break. Personally I'm going to do mine a minimum of 3" unless I'm trying to get more spine, then I'll do the whole thing longer, taper included.
Matabele, he uses extra glue then points them down. The glue I use won't run so I don't use any more then needed but still cure them point down just in case. :)
What an irony...Not many years ago I didn't like carbon shafts cause they produced an over all arrow that was too light. We were shoving weights of all kinds inside from skinny aluminum shafts, to aquarium tubing, to sand! :) ..The manufactures stepped up and started making carbon shafts with good mass...Now I want shafts that weigh nothing! :) We had the right shafts and didn't know what to do with them....O.L.
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Thanks O.L. !!!
Very helpfull. You guys are our R&D wing of traditional archery. :clapper:
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Dave, Ed here.
Regarding the 2" vs 3" glue attachment, what I found in testing was that I needed a MINIMUM of 3" of total glue attachment to the shaft's inner-wall in order to prevent set-back on direct impacts. That's with having a glue dam (glue ring) back of the IF's parallel portion. That 3" MINIMUM includes the length of the brass insert PLUS the area of glue attachment for the IF.
Since all my work has been with the long, 100 grain brass inserts I need a minimum of 2 more inches of attachment on the IF's front. More doesn't hurt, and I use 4" of parallel attachment length on the 9" IF's I sometimes use (depending on what I need for weight and bare shaft tuning).
Just keep the MINIMUM TOTAL length of insert/IF glue attachment to the shaft's wall at 3" or more - and keep the flexable, parabolic tapered portion of the IF a minimum of 5" long for those forceful angular impacts.
Hope that helps,
Ed
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This is good stuff...GREAT THREAD!!How much does those carbon RODS weigh roughly per" ??? Has anyone weighed them??
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I for one don't look for a "high" foc. I put my arrows together to be well balance with the 6 to 7% foc. They fly like darts and stay within the recommended grains per pound for the bow I shoot. And let me add, not penetration problems here. That's what works for me. mr.c
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Thanks Doc,Thanks O.L.,
Regarding 2" vs 3", the info from you guys is always helpful!!
(actually sprung loose with some gelt and bought me a drill press !)
:scared:
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ttt
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Just checking to see if any you guys have done a batch of MFXs or Axis using this method? I thinking of tring sum with the carbon footings, wondering how much weight it adds?
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I just made a batch of GoldTips 35/55 for my 50# Widow with a 7" IF.They fly great,took 3 hits from a patioblock and still perfect!! My only complaint is the tickin noise I hear when shot.I put epoxy up the shaft,on the IF,then insert, then slid all in.Has anyone run into this??
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ticking noise? thats interesting i guess the IF hitting the inside of the shaft, does it do this with every arrow?
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I made one arrow that flies well with the IF of hardwoood a couple of weeks ago and today I've been working on gluing up another 8 of them! :D
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Kind of a sideline but....
This does seem to end the debate of wood vs. Aluminum vs. Carbon since all three materials are used in this arrow build. It seems we have now found the perfect arrow and it requires a combination of all three materials!!!
GREAT THREAD!!!!
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Made up 6 of these and the ticking, rattling from
the arrows paradox hitting the wooden insert is
way to noisy for hunting imho.
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Yeah I noticed the same thing. Clank.
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:campfire:
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I made up a set of GT 5575's recently and installed 7" IF's in them.They shoot well and I was surprised that the IF didn't change the tune of the arrow.
They are noisy though,so noisy,I would never hunt with them.They are being relegated to squirrel and stump arrows.I wish I had that to do all over again.
I put a lot of time in those arrows.
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I'd like to hear more about this noise issue before I make up some of these.
The Perfect Arrow ... Not So Perfect?
Anyone?
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I don't get any noise or"ticking". I made mine only 5 inches long though. I will say they are indestructable. Made up a set for my elk arrows.
Steve
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I have done this with the 5" taper. I have a slight tick if I have hammered the snot out of the arrow a few times and I hold it by the fletch and bounce it off my hand in the centre. Having said that I never have a noise issue from up a shot and they fly great I have hit a few on ricks and you can see the front trying to split but the glue on the brass insert and then the 2" of wood keep it solid.I really like this set up and I think it makes them stronger
Allan
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again
ChuckC
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I made 2, one is silent, no noise at all. The other ticks. I think the first one has a better taper(centered) and the other might have been a little crooked.
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Just came across this thread via another. OL and Ed never responded about the noise comments. I am curious to hear more. The whole point for me is make an indestructible elk arrow. I could care less about shooting armoured vehicles. ;) I have had enough arrow and broadhead failures to remain on the hunt for the "perfect arrow" as OL claimed. Too noisy to hunt with? Is this worth playing with?
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I'm curious too about how to make sure these things stay silent. Any more tips/feedback?
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I made a couple up that were really quiet. You have to make sure you have a consistent rounded taper and the dowel fits tightly in the shaft. I ended up using an epoxy that is designed for golf club assembly. It worked great, until I lost them shooting at squirrels. I used an AD Hammerhead, and a hickory dowel. With Stos and Eclipse heads, they were as quiet an arrow as I've ever shot.
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Pulling this up again for OL to hopefully respond to the noise issues. Why are some guys noticing it and others don't? What is the difference?
Cheers,
James
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I built up 2 of these arrows as a trial and they seem to shoot great with the weight forward but I do get a little "click" or "ting" when I tap them against my hand or something else. I do not really notice it so much when I shoot.
I plan to grab some wool yarn and wrap it around the tip and hopefully that will muffle the "tick". I will let you guys know how it goes.
I wish there was an easy way to make the tapered wooden dowels. So far I have made up 12 wooden inserts and they are somewhat similar though not exactly the same as one another. I am not so sure it is worth the time and may just prefer to buy more arrows instead of spend so much effort to make a dozen "Perfect Arrows". Have you guys come to the same conclusion?
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Good Luck!!! OL was too busy with this thread, flight shooting, and model planes instead of building bows he'd taken deposits for. Some guys are still waiting on bows so I doubt you will see him posting anywhere on the internet. He's been shamed into seclusion so to speak since he took deposits and never delivered.