By: John C Henry
Recently, I’ve been spending a good deal of my time and testing equipment looking into the information on the new Aerovane Fletching jig from Firenock. I often appreciate new information, but also do a great deal of research to verify and validate information before I’ll pass it along to others.
The good news is that I’ve found Dorge O’Huang, the owner of Firenock and inventor of the Aerovane Jig to be far more technical than any of us ever dreamed possible. Aside from a double engineering degree, Dorge has had extensive direct experience in a number of technically related fields. Needless to say, he researches everything to an exhaustive degree. As such, his information is his attempt to actually simplify a small part of what he has learned or already knows.
While it’s true that his nocks are far superior to those produced by anybody else, there’s a lot more to his products than just the simple things we’ve already discussed. One in particular is the margin of error within the Bitzenburger Fletching Jig.
I’ve used a pair of Bitzenburger Jigs for the past twenty years and have always been very partial to these jigs. My uses have been exclusively 3 vane or feather fletching of either competition or hunting shafts ranging from every grade of aluminum to carbon / aluminum shafts from Easton.
I had never paid a great deal of attention to how much deviation or movement these jigs had and always assumed them to be fairly accurate with the selected indexing. Boy was I wrong!
Recently, while producing the 60 x 120 degree four fletches for the TAC arrow shafts, I began measuring and comparing these finished arrows and I was also checking to see if the 60 degree spacing was really 60 degrees, as well as verifying if the 120 degree separation was in fact 120 degrees.
That’s right, you guessed it, these measurements were way off and they were also different from arrow to arrow, even though they were coming off the same fletching jigs. Needless to say, I was very upset.
I just spent hours and hours “Spine Testing”, Sorting and Matching a couple dozen arrows. I spent extra hours matching shaft weights to the 100th of a grain (+ or – 3/100ths) and now I would need to remove all my vanes, clean down the shafts and re-do the fletching with a better quality jig.
I just learned an important lesson the hard way. I wasted the money of another couple packs of 50 Duravanes and probably almost a dozen hours of my time before all is said and done and I wouldn’t have ended up with the matched set of arrows that I was seeking to begin with.
The other big thing that I learned was in the bonding process of the Duravanes. Today, almost all manufactures are using Fletching jigs that are angled upward but the glues that are being used are liquid cyanoacrylate ester based glues. Most of these glues run like water, so an angled Jig is very difficult to use effectively without it running all over the arrow shaft and making a mess of a brand new arrow shaft.
The more important factor is that in order to achieve a vane to shaft bond that is capable of withstanding a few thousand pounds of force can only be achieved with 40 or more foot pounds of evenly disbursed downward clamp pressure.
The Bitzenburger Jig does not apply even downward pressure along the length of its clamp and 40 lbs. is way beyond the capability of its magnets. It’s not level. so getting good even distribution of the glue is also not possible, so the problem with the vanes coming off on target impact is not just a problem of the glues that are being used, it’s equally a problem of how the vanes are being applied to the shafts both at the factory and during home repair.
I hate to say this, but I’m going to be the one to stick my neck out and open the can of worms on this problem. Unless TAC owners are willing to invest in the right Fletching jigs to properly apply vanes to their arrow shafts, they’ll be replacing vanes regularly forever. Eventually, it’s going to cost them as much in vanes, glue and time as if they had just purchased a good fletching jig to begin with.
It might also be worth noting that there are only three commercial manufactures of the type of glue that I mention above, so it doesn’t really matter which ones you try because in most cases you are using one of these manufactures products that are packaged and labeled for a particular seller or distributor.
The strongest bond between arrow shaft and vane is obtained with the thinnest coating of glue and the greatest amount of pressure applied evenly over the length of the vane. These bonds are so strong that the vane will rip or tear along their length long before the bond ever lets go.
The net, net of this whole thing is that while the Aerovane Jigs are a bit pricey, they’re actually cheap when you understand what you are getting and exactly how many problems you are overcoming.
After seeing the difference these jigs have made and the type of bonding now attainable, my recommendation is that if a TAC owner is willing to spend between $1500 and $2200 on his xbow and buy arrows that are $90. per half dozen, then do yourself a favor and save your money long enough to purchase an Aerovan Fletching Jig, because it’s the only thing that’s going to solve a number of the problems with the accuracy and durability of the ammo used in these crossbows.
Dorge probably thinks I should work for him, but a good product is worth recognizing when it comes along, so for this one he gets a thumbs up.
For more go to: Aerovane Fletching Jig
How much? How much off were the degrees of separation if they were not 120°? Why were they way off? Did you remove the nock set to measure the indents in the nock set? Were you using a loose nock? That would certainly cause it your degrees of separation to be erratic.
I was not using a removed or loose nock.
The TAC15 arrows have a relatively wide opening on there nocks to begin with. This can account for a small amount of variation on each rotation, in the area of 2 or 3 degrees.
Also, the Bitzenburger Jigs have a certain amount of rotational play or slop in the jigs when turning the receiver dial because they’re not machined to tight enough tolerances and they tend to wear over time.
Last and most importantly, the magnets are not very strong and typically can’t hold the clamp rigid enough to maintain consistent downward pressure for precise placement of the vane on the arrow shaft for each vane.
Each of the slight deviations cause variations for vane placement as a user rotates his placements around the arrow shaft. Once any single vane is out of alignment the problem can throw off the other vane spacing on the shaft.
My testing showed spacing deviations anywhere from 3 degrees to as high as 7 and 8 degrees. This is substantial when you are looking for precise arrow to arrow performance, such as used in either competition or any type of long range shooting. Even at closer distances, if you’ve experienced situations like when shooting a four or five arrow group at twenty or thirty yards and you have three arrows in a very tight group and one or two that always seem to be an inch o two outside the others, this can easily account for tha type of variation.
When you put a broadhead on your arrows these minor flight deviations become much worse and more pronounced.