You posted a reply recently on Tradbow in response to a query titled "Why 25 1/2 degree angle of cut?", that I started. I have a personal questions of follow up for you, not related to the thread, so contacting you here. Ashby as was posted, confirmed 25 1/2 degrees to be ideal.
I use the KME as expressed, and I understand your explanation that the KME jig may read different than the actual factory grind. It remains unclear to me if the TuffHead can be sharpened to a true 25 1/2 degrees or not, without grinding the ferrule, if I use the KME on a Tuffhead BH. I will be in the market(know of 3 others also) for new BH, and all are looking to follow Ashby's recommendations. Your head is well done and on a short list of possibilities.
One of the other posters to this thread at Tradbow said it is not possible to sharpen without grinding the ferrule, but I am not certain if that poster understood the KME jig may have been cutting a true 25 even-though the jig stated otherwise [due to the relationship of the blade being closer to the jig pivot point, as you attempted to clarify]. The dims of the 225 and 300 appear to be the same, but my selection would be with regards to either of these 2 heads. If they would require a grind to the ferrule at 25 1/2 degrees, do you know at what true blade angle the ferrule would not have to be ground? I also would hate to not consider your head because of the KME. How much can your ferrule be ground if needed, and not compromise your head? Are there other sharpeners you personally prefer? I have talked to Ron Swartz in person and believe him to be of good character, and a maker of a good product, but this does not wed me to his product. The BH is more important than the sharpener in my opinion.
Of the BH's on my short list, only 2 others have a smooth ferrule taper(Grizzly and Aboyer). The Grizzly taper starts just a bit further back from the tip than yours and the Aboyer noticeably more so. Though both have a smooth taper, the further back it starts increases the angle assuming equal end diameter which increases resistance. Did your testing show a marked improvement in penetration by placing the ferrule to the tip as you did, or was this done upon theory alone? Was this effective only for wood arrows, or also if inserts are used to accommodate a screw in ferrule and using carbon?
Further, because of the convenience of removing a 'rotating' single bevel from a target when it has threads, I would install your head with inserts on an anticipated use of an Easton FMJ arrow(BH almost always out back of target and easier to remove than yanking back through). Are the inserts engineered with the same attention to detail the BH was given?: I am assuming this will make my BH alignment much easier which is my concern. I am a stickler for a well tuned system and uncertain of the degree of effort this will be using your product. I know it is possible. A well engineered system makes it hard to not get the alignment right.
Last, have you ever considered a BH design for narrow carbon shafts that would have a narrower ferrule dia. and an aligned/installed insert, that a small diameter arrow such as a FMJ from Easton would still easily clear. 3/8 is quite a bit(IT IS ALL RELATIVE ), of unnecessary extra bone to push a wider ferrule through, assuming a narrow dia. shaft is chosen. I understand Ashby's study suggests bigger BH than shaft is much better than the arrow than equal in size. Plus a narrower ferrule would allow more clearance for a jig like the KME. Just a thought.
Thank you for your reply in advance. No rush on the reply should you be hunting. Also, thank you for making available the well designed BH you have.Richard L.
And Joe's Reply...
Richard,thanks for your interest in the TuffHead, I will try and answer your questions and hope I do not miss something.
If you take a straight edge and hold it flat on the 25 degree bevel and hold it to a light you will one be able to tell if the edge is flat on the bevel and you will also see the light between the straight edge and the ferrule. I don't know why anyone would be into the ferrule unless they are at the wrong angle or have to take enormus amounts of metal off. There is at least a 32nd clearance. Under normal conditions this would be years of sharpining. If there was not clearance the blade could not be sharpened with a round stone, which it is, as the stone fronts edge sticks out further than the grinding surface and would grind the ferrule.
The steel on both the 225 and 300 are both quite thick and grinding slightly will have no effect. In my previous life I used zewickys and sharpened with a file. The method that was common was to lay the file on the ferrule as a guide for sharpening. Hitting the ferrule of the TH is not recommended nor is it necessary but will not really hurt any thing except appearance.
My recommendation is the KME when the edge is damaged. Most of the time the edge can be brought back just by stropping. Stropping will handle most situations.
It is not easy to change the ferrule design with out changing the die. I have $30,000 in my die and no desire to make a new one. I believe the ferrule design that is in the TuffHead is the best for all arrow diameters , although you are not he first to question it. When using skinny arrows people think they need a skinny ferrule. That is not the case.
I will admit it does look different only because we are programed to see no space between the arrow and the wall of the ferrule. Just as some think it a sin to have the arrow extended more than a inch beyond the shelf of the bow. Another fallacy if you want to tune arrows
The ferrule extended to the tip was designed mainly to strengthen the broad head .Our testing showed that a high MA head (long) is prone to bending in the area between the ferrule and the tip when there is a flat area or void between the ferrule and the tip thus the extended ferrule. We eliminated that problem. In theory we also thought it would help penetration. Testing now shows it is better in bone penetration then those broad heads that do not have ferrule extended to the tip. The ferrule design is defiantly a plus .
Up to this point we have purchased our adapters from Three Rivers or Kustom King. However we have had a problem with the ferrules bending on heavy boned animals especially using heavy arrows of 800 grain plus. We are in the process of building a titanium ferrule. As far as fit, any ferrule with a 5 degree taper which is all of the commercial adapters will fit the TuffHead nicely. I will refer you to a recent post in on adapters for more information. For alignment it is best to use a commercial aligner system Do not try to spin the Tuffhead by the tip on a table or flat surface as the way the tanto tip is ground it could give a false reading
The type arrow you use aluminum,carbon or wood the TuffHead will out preform most others. But a course I would say that.
Richard again thanks for your interest and your nice letter.
Our good friend Jim Brandenburg hones his TuffHeads to a mirror finish with the KME system and provides this descriptive lesson in bringing your TuffHeads to the same level. Read More...
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