Tuff Heads on order...

[amar911]

Posted by Joe Furlong of Tuffhead at this thread     http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=1&t=127914    


Allan,

Finally got the grade five titanium adaptor perfected and in production. The grade five titanium has almost 2.5x the tensile strength as the low carbon steel used in the commercial steel adaptor. Testing has real good results. They were actually used on Buff's elephant hunt with no bending detected. Expensive but worth every penny on dangerous game. They weigh 75 grains but are actually the approximate size of a steel 125 grain. They fit clear up the 5 degree taper on all standard broadheads. A picture is up on the "Shop" section of  www.tuffhead.com  . If an adaptor can be termed beautiful, this one would fall into that category.  

Hopefully this will solve the problems with the weak link.

--------------------
Joe Furlong

    http://www.tuffhead.com/

[BUFF]

Joe sent me the titanium adapters for my elephant hunt.
I hit a rib going in and put a slight curve in the first inch or so of the head. No damage to the adaptor at all.
That is a 85 pound bow slamming. 1100 grain arrow into a elephant rib.
I think you can safely say he has it figured out  

[stalkin4elk]

I am very interested in the bending adapter problem as well.
For the record, tensile strength is defined as the stretching force required to break an object. (The opposite is compression force that resists being crushed). Think of a "tug of war" game. Tensile strength of adapter never was the problem nor will it prevent bending failure within normal limits.    
We need a material that greatly improves the bending resistance(moment) without becoming brittle and breaking. Possibly titanium is this material, however it is very light and it would be nice to gain FOC with a heavy material as well.
I have always thought we need a reverse thought process so that the BH insert would glue into the shaft for maximum diameter and then this solid male threaded adapter would thread directly into a female threaded BH or FP. The length would determine weight.
I am afraid to think of what the cost would be for the machine work to build this adapter and also retool/machine a BH design. Any guesses for final cost Joe?
Don't get all excited guys I am just kicking the tires on a rainy day.

The entire Elephant deal is IMPRESSIVE!

[Roger Norris]

They are my broadhead of choice for this fall also.

They fly great, are exceptionally well made, and they sharpen very easily. Do yourself a favor, order the sharpening accessories that Joe sells. Awesome.

[vintage archer]

STALKIN4ELK

Jim ,your have a point about compression although  I am not sure what the action or reaction is that bends the threaded section of  the adapter. Could be some of both compression and stretch. I have not been able to pin point exactly what happens right before bending. For lack of solutions I am just trying to strengthen the "weak link".

There are not  tables readably available for compression as there is tensile strength.

The following quote is the reasoning for quoting "Tensile Strength" when comparing metals.

"For most structural materials , the difficulty in finding compressive strength can be overcome by substituting the tensile strength value for compressive strength. This substitution is a safe assumption since the nominal compression strength is always greater than the nominal tensile strength"


 file:///Users/josephfulong/Documents/Material%20Strength%20-%20Strength%20(%20Mechanics%20)%20of%20Materials%20-%20Engineers%20Edge.webarchive

In other words if Titanium has a higher tensile strength than low carbon steel or any material that you are comparing it to it is also stronger in compression

Thanks for bringing up the question the more input we get the better ..........We all share this problem no matter what broad head we shoot no broadhead or hunter is exempt  

[Fletcher]

Steel will stretch, but for all practical purposes, you really can't compress steel, except to bulge it out like a rivet.  Any non-torsional metal failure I've seen has been on the tension side.  If an adapter fails, it will be at the head to shaft joint, and the failure will be stretching of the metal on the outside of the bend.  Stretch it far enough to exceed the elastic limit and it will break.  I'm not an engineer, but I don't believe it will make much difference which direction the joint screws together.  The limiting factors are going to be the tensile strength and diameter of the insert shank.  A larger OD at the shaft to head mating surface will increase strength of the joint also.

[stalkin4elk]

Thanks for the feedback guys. It's frustrating to have such great quality shafts and broadheads only to have a darned adapter cause problems.

[BUFF]

I really think.... No really I do sometimes


That when a adaptor bends, it is because the broad head has stopped and the arrow is trying to pass.

I shot a impala last year and the arrow stuck in the off side shoulder. I was watching the video frame by frame on the camera. There was a moment when the head stopped and the arrow looked like a snake.

[vintage archer]

BUFF  I have seen pictures of that also taken with high speed cameras.  When the arrow comes to a abrupt stop the arrow goes through a paradox similar to when it leaves the bow.It could be the momentum of the shaft causes the bending. Like you say the broadhead is stopped and the arrow is still going. This might explain why the bending is observed more in heavy arrows.

[Al Kidner]

I know one thing... I am as keen as to send one of these BHs through a critter!

My BHs turned up here the other week and I am more then impressed with the quality and attention to detail in a simple BH.

Africa in August... Here I come. Armed with Tuffheads!


ak.

[zipper bowss]

I have a small sample of steel inserts that I am playing with heat treating. It will take a few weeks before I know anything but I'll be sure to share any results.
Bill

[slivrslingr]

Great discussion guys!  

Go get 'em Al!

[Steve O]

Originally posted by vintage archer:
BUFF  I have seen pictures of that also taken with high speed cameras.  When the arrow comes to a abrupt stop the arrow goes through a paradox similar to when it leaves the bow.It could be the momentum of the shaft causes the bending. Like you say the broadhead is stopped and the arrow is still going. This might explain why the bending is observed more in heavy arrows.

Makes perfect sense to me.