# Video; Pressing X-Force & any other bow



## ken Johnson (Apr 5, 2007)

Several AT members have asked to see a video of how the Nite Hawk Bow Press works. So we made one. 

To see it, goto www.nitehawkarchery.com and press "Bow Press" on the left of page, you'll goto the bow press page and the video. 

I hope you enjoy it. Making it was a new experence for us.

Have a great! 2000 & 8.

Ken


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## Gils4x4 (Jul 8, 2005)

*Wondering the Difference*

I am looking into a portable press and was wondering why this is different than the Rachet Press?


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## Slice (Jul 20, 2005)

It ask me for a username and password


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## rpford53 (Jul 21, 2006)

Nice little press, would be great on hunting trips.


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## ken Johnson (Apr 5, 2007)

*compared to the retchet press*

If I am thinking of the right press, it uses a ratchet to compress the bow.

A ratchet does not offer total control of the compression or the release that the turnbuckle does. 

If it is the press I'm thinking of, it presses from below the cams not at the ends of the limbs, so it is harder on your bow then the Nite Hawk. 

It can not be over emphasized how benifical it is to press at the ends of the limbs. The end of the limb is the part of the limb you want to move, and it is the part of the limb that is easyest to move. So you apply less force to your bow and you can press any kind of limb because they all have an end.

I have never used one so I can not compare ease of opporation. 

The Nite Hawk may cost a few dollars more.

These are a few of the basic differences I see.


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## Pa. Shooter (Jan 31, 2004)

*Nice Job !!*

I think you have a Very Nice Press !! Great Job on the Video !!
Very Innovated.

Steve


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## Slice (Jul 20, 2005)

Great video...


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## francis (Jan 18, 2003)

ttt


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## Daniel Boone (May 31, 2002)

*Mathews Techs*

I wonder if Mathews or other Companys are going to warranty the bows used in these presses.


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## Andreas (Jan 7, 2004)

I recently bought the Nitehawk press and in my opinion it's likely the best portable press avaliable. I thought the Bowmaster with split limb adapters was great but you cannot press bows that are parallell or beyond with the Bowmaster. 

I think the ratchet look and those other ones alike is a different story since they press below the cams and not on the limb tips. The required amount of pressure for is way lower for the Nitehawk.


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## Shooter Mike (Oct 27, 2002)

My concern is the distance between the retaining pin and the pressure point is short to the point where there's a high amount of bending force in a short distance, which puts a high amount of stress in a very vulnerable area of the limb. Yes, the whole limb is bending, but the highest amount of pressure is the last few inches of the limb. 

It would seem that a longer frame that reaches down to the limb pocket would solve this potential problem, by applying force over a longer range of the limb, and at a less vulnerable spot on the limb. 

Nice press, though. I definitely like the turnbuckle idea much more than a ratchet strap that "lets go" when it's time to decompress. The turnbuckle gives positive control when decompressing the limbs.


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## stinky1 (Feb 20, 2003)

regarding the poll. i lost interest right away and didn't get too far in the video before I closed it.


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## ken Johnson (Apr 5, 2007)

*Shooter Mike*

Thanks for the comment. 

To describe the working of the pressure point and the pin, the pressure on the limb at the pin is half or less then that of the pressure points. The distance from the strap to the pressure point is about half the distance from the strap to the pin. Which equates to 1/2 half of the draw weight, since the pressure point is near the axel and exert pressure about equal to the draw weight. 

Also the press floots on the limbs. So the limbs flex in their normal curve. I had hoped the normal flex would showed in the video. 

Every thing happens without much force. That is why the turn buckle works by just hand turning.

Thanks again Mike, good hunting


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## Jamesw (Sep 14, 2007)

It looks like it works well and easy.I think if it was me I would get them put on the aproved list for PSE and Bear Archery if I could.I think more people might buy them if they saw the manufacturer agreed they would work on there bows.A lot of guys are very leary of pressing a bow that cost several hundred dollars without seeing that the press they were buying was approved for use on there particular bow. jmo

I am buying a new Bear and it's limbs require to be pressed like the x-force limbs but the Bowmaster is the only portable that Bear appoves right now.


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## Snowcamphunter (Nov 26, 2007)

Whisper creek archery says you can't press their bows on the end of the limbs


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## badbow148 (Dec 5, 2006)

I am like it and the turn buckle is awesome will have to have one I believe. I like my Bowmaster but this is better I believe.


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## ken Johnson (Apr 5, 2007)

*Thank you for all the comments.*

Thanks for all your comments. 

We are sending out letters to get our press listed with bow makers. 

We take your advice very serious.

Thank you again.


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## jkeiffer (Aug 3, 2007)

ken Johnson said:


> Thanks for the comment.
> 
> To describe the working of the pressure point and the pin, the pressure on the limb at the pin is half or less then that of the pressure points. The distance from the strap to the pressure point is about half the distance from the strap to the pin. Which equates to 1/2 half of the draw weight, since the pressure point is near the axel and exert pressure about equal to the draw weight.


On a bow such as the X force the force on the pins is much more than half the draw weight since there is a lot more force exerted by those limbs than 70 lbs, the draw weight is aquired by the cam system, which is basically levers that change thier length through the draw cycle to accomidate for string let out as well as increased loading due to increased limb deflection.

PSE would probably approve the press *IF* the parts of the press that press against the underbelly were right in the pocket.

I love the concept but Trust me over time you will want to be pressing right next to the pocket.

good luck.
jkeiffer


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## ken Johnson (Apr 5, 2007)

*JKeiffer*

You are right. The draw weight of a bow it not exactly the same as the force on the limbs. But it varys only by the difference in the diameter of the cable cam and the bow string cam. Since generally speeking the cable cam is the smallest of the cams the cables support more force then the bow string. But we have to remember the shape of the cam has much to do with the forces exerted on the limbs. 

But please keep in mind when pressing a bow you start pressing it the lowest point on the limbs power curve. As you draw the bow the force on the cables(limbs) increase to their maximum which I am sure is greater then the draw wieght. The limb force move from low to high.

Since the Nite Hawk press presses at the ends of the limbs it has only to overcome the lowest point on the power curve. This I assume is near the draw weight. 

Since the limbs and camming varys from bow to bow one would have a great deal of trouble determining the power curve and caming of all bows. Therefore, it seems reasonable to use draw weight as an approximate force. which I think is a good approximation.

Thank you so much for you analisis. Please tell me what and where is the pocket you mentioned?

Have a great day!


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## nccrutch (Feb 26, 2003)

I think jkeiffer is talking about locating the pins at these points, where the riser meets the limbs.


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## ken Johnson (Apr 5, 2007)

*Reply*

One of the nice thing about pressing a bow this way is that the press moves with the limbs. The pin could be anywhere between the pressure point and the riser and the limb would be pressed over its entire length. 

The video shows this happening, the entire limb moves. This is best seen on the x-force where the limb has near consistant thickness from the riser to axel. The pin, frame and limb all move in a smooth arc from riser to axel. Even the end of the limb follows the same arc. The pin does not prevent the limb from bending between it and the pressure point. 

I am looking at putting a bow scale in along the strap to measure the pressure the turn buckle exerts. It will take a couple of days to get the clamping needed. This will give me a better idea of how much pressure is being put on the limbs. You guys have got me curious.

Have a great day.


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## reylamb (Feb 5, 2003)

Sorry, physics disagrees with you, there is that whole reaction, oppossite reaction thingy going on there...........see if you can figure out where those actions are.....

The PSE engineers I spoke with at the ATA were not all that enthusiastic about your product either.

Me......no thanks, now or ever.


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## ken Johnson (Apr 5, 2007)

*The proof of the pudding is in the eating.*

We have had no complaints so far. 

The biggest surpise users have is how easily the press presses their bow. Like the video show you only need to use one hand to turn the turn buckle. 

I do not know who you talked to at PSE, but no one at PSE that I know of has ever used a nite hawk press or even seen our video. 

I just wrote them so I may hear from PSE in the future, but that will be their choice.

I am going to put a bow scale into the strap to measure the pressure on the strap just because you have got me curious. Hopfully it will happen this week.

Thanks a lot and have a great day.


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## reylamb (Feb 5, 2003)

ken Johnson said:


> We have had no complaints so far.
> 
> The biggest surpise users have is how easily the press presses their bow. Like the video show you only need to use one hand to turn the turn buckle.
> 
> ...


There was a thread on their forums showing your video..............so yes they saw the video......but removed the thread.


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## danslaugenhoup (May 22, 2006)

*Just got mine!*

I have to say I just recieved mine and can tell you it is the best press I have used in a long time. I wasn't sure if I would like it but it is truly a nice design. It takes very little pressure to press. I was shocked. I have used many types and this works great. You can leave your limbsavers in and don't have to worry about ruining your limb decals. If you haven't tried one it is hard to believe. I'm glad I did. Good luck Ken.

Thanks
Dan


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## NMP (Aug 6, 2003)

I will try to explain what these guys are trying to say about the pin placement that you have. Do this test when you get a chance and you will see what they mean. Get a 1/2" thick x 2" wide x 2.5' long piece of wood that doesnt have notts in it and clamp the very end of the piece to a table leaving about 1.5 feet hanging over the edge of the table. The clamp will act as the limb bolt and the edge of the table will act as the fulcrum or your bottom pin of your portable press. Now you just want to push down on the other end of the piece of wood hard enough to break it. This will tell you where the majority of the pressure is being applied in your design. I am willing to bet that the wood will break at the fulcrum and not at the clamp which is where bow limbs are designed to have the most pressure. This press is probably Ideal for center pivot bows though as there fulcrum is in approximately the same place as your presses is when installed. I am sure that the press works just fine for you and your customers but it is hard to see how the press is any safer on the limbs than just puting a rod through the cam of the bow to change strings. This is the same reason that lots of people bought the bowmender instead of the ratchet loc. I am not nor will I be bashing this product. I just thought I would try to better explain some of the concerns brought up in this thread. Please keep us posted on what you find out in your test with the scale on the press as well.


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## danslaugenhoup (May 22, 2006)

*Not how it works!*

The fulcrum is not were the pin is put in on the press. The whole limb moves as you press. Have you ever used a cheater bar on a wrench? It is the same idea. You are pressing the whole limb not just half. Were the pins go in move freely. YOU ARE NOT JUST BENDING THE ENDS OF THE LIMBS.


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## NMP (Aug 6, 2003)

There is no other choice but for the whole limb to move. It will have to. Think of it this way. If the piece that contacts the limb tip is an equal distance from each end of the fixture and you must apply say 70# of pressure to the strap with the turnbuckle to relax the strings then you are applying 70# of pressure to the other end of the fixture which is in a place most limbs are not designed to have that pressure. The longer the distance from the limb tip contacts to the ends with the strap and turnbuckle the more pressure is being applied to the middle of the limb. The example that I gave earlier is still an accurate way of determining what point will have the most pressure applied. Like I said before, I am not trying to bash the product but this is the way it works. Remember every action has an equal and opposite reaction. its a law that applies to levers of all kinds. About your cheater bar on the wrench, have you ever bent a wrench when doing this? If so where did it bend? I have and it will allways bend at the end of the cheater bar.


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## danslaugenhoup (May 22, 2006)

*Example?*

The example you gave is not how it works. You are misleading people. 
I just don't think it is fair to do that. I'm just here to say it is a good product. I would recommend.


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## NMP (Aug 6, 2003)

danslaugenhoup said:


> The example you gave is not how it works. You are misleading people.
> I just don't think it is fair to do that. I'm just here to say it is a good product. I would recommend.


I am not trying to mislead anyone about anything here. Please explain in detail how I am doing so and correct me if I am in fact wrong. I am not the only one that feels this is the way this product works evidently so educate us. I only tried to show you that you are puting undue stress on the middle of the limb which is not a place that was designed to be stressed on most bows but never said that it is enough stress to cause damage. When you use this press on your bow you have added another rocker to the center of the limb, approximatly, have you not? The equal and opposite reaction of the turnbuckle is not relayed directly to the limb pocket but is being distributed to the appriximate middle of the limb. That is right isnt it? I cannot see how it could work any differently. If it does please help me to understand. The pressure applied with this is approximately the same as partially drawing the bow and sticking a pin in outer perimeter of the cam to make a string change. I dont want anyone mislead so again please correct me if I am wrong. I like many am just trying to understand how it is different than I have described. BTW, if you think I am trying to mislead people because I build bowpresses for a living then you are mistaken. I have no intentions of producing a portable at this time so to do so would not even benefit me.


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## danslaugenhoup (May 22, 2006)

*Hmmm?*



NMP said:


> BTW, if you think I am trying to mislead people because I build bowpresses for a living then you are mistaken. I have no intentions of producing a portable at this time so to do so would not even benefit me.


I'm glad you said it and not me. Most people only buy one press either portable or not. Good luck to both of you.


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## NMP (Aug 6, 2003)

danslaugenhoup said:


> I'm glad you said it and not me. Most people only buy one press either portable or not. Good luck to both of you.


No matter what you think my intentions are this is still a concern of people about this press that has been ignored every time it has been brought up in a thread and the company could really benefit by puting these concerns to bed and explaining how the pin placement has no ill effects on the limbs because it goes against everything that people have been taught about compressing the bow limbs.


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## reylamb (Feb 5, 2003)

Let,s put this in physics terms. I am going to upload a picture of the 2 forces that are acted upon the limbs by the press. The red arrows indicate the force on the tips that presses the limbs. The blue indicates forces in the opposite direction at the fulcrum point of the press, the whole equal and opposite reaction thingy.

Since from physics we know, and no one can argue, for every action there is an equal and opposite reaction we can then surmise that: 1)there is some force being applied to the limb tips; 2) there is an equal force being applied in the opposite direction at the fulcrum point; and 3) the limbs on this bow are not designed to have outward forces applied at that point of the press.

While yes indeed the entire limb surface moves inward, there is still an undeniable force, equal to the force being applied to the tips, that is exerting force outward at the location of the lower pin. The limbs are not designed to have forces exerted in that direction. 

The better way to do it is to locate the lower pins at the limb pockets where they attach to the riser. While the same force will still be exerted in the opposite direction from the limb tips, the limbs are supported in that location by the limb attachment, pockets, or riser (whatever is actually at that point).

This design would likely work fine on the Bowtech guardian, commander, general etc (although my post should not be taken as an official statement from Bowtech as approval of this press for their bows), because the limbs on those bows are supported at the location of lower inside pin. However, conventional limbs offer no such support at that location and conventional limbs are not designed to have outward force applied on that part of the span of the limbs.

A slight re-design to allow the pins to be located at the point where the limbs attach to the riser would be better for the limbs, rather than the fulcrum being located in the unsupported area of the limbs.

I do not disagree that the entire limb moves in. However, force is being applied to the limbs in the opposite direction from the tip and the attachment location at the fulcrum location. What you get, in simple terms is <, with the tip coming in and the middle being the fulcrum. Granted the actual forcs are more circular than linear, but you should get the visualization here.

Just get the pin lower so you end up with / and not <.....


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## ken Johnson (Apr 5, 2007)

*relamb*

Your quote on opposite forces is correct. But does not apply to the Nite Hawk Press in term of amount of force. 

What does apply is the law of leavers. 

Looking at the picture you have showing, the frame is a leaver and applys pressure to the end of the limb and at the pin. The point where the turn buckle attaches to the frame is the folcrum. Because the distance from the turnbuckle to the pin is twice as long as the distance from the turnbuckle to the presure piont, the law of leavers would state the length of the leaver times the foce applied should be the same for each point. Therefore the pressure point exert twice the force as the pin. L= length of leaver form turnbuckle to pressure point. (Force at pressure point*L = Force at pin * 2L)

Force at pressure point is twice that of force at pin.

The direction of the force does not change the amount of force.

I hope to put the bow scale into the strap to measure the actual force applied to the strap and the bow limb.

I will let you know the results.

Thank you & have a great day.


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## danslaugenhoup (May 22, 2006)

*Well said Ken.*

I am really satisfied with your press.
Thanks
Dan


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## ken Johnson (Apr 5, 2007)

*I put the bow scale in the strap.*

I wanted to put a bow scale in the strap of a Nite Hawk Press to determine how much pressure is needed to press a bow. I had expected that it would have taken force similar to the draw weight of the bow, but it took 1&1/2 time the draw weight to press the bow. My 60# pound bow needed 90# of force on the strap. The actual force on the ends of the limbs was about 180#, twice that of the force on the strap.

I arrived at the 180# using the law of leavers. Note picture of cam and bow press frame. It works like a teeter-totter. The strap pulls down and the pin goes up, the pressure point at the center is the fulcrum. The pressure point is pushed down with the sum of the force on the strap and the force on the pin. With the pressure point in the center of the frame, the leavers are the same length so the pin force and the strap force would be equal. When I pressed the 60# bow, the press applied 90# to the strap, the same 90# to the pin and 180# to the pressure point. All the time I believed it would be less because it is so easy to turn the turnbuckle.

How would that effect your bow's limbs. It has no more effect on your bows limbs then drawing your bow. Remember the press floats on the limbs, so it has the same effect on your limbs as your bow string and cables. 

Think, if it takes 180# to draw your bow at its axels, then how would 90# harm your limbs between the cams and the riser where the limbs are heaver.

Thanks for your interest.


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## reylamb (Feb 5, 2003)

How you can surmise that the pin is not the fulcrum is beyond me. Remove the pin.......will the bow still be pressed? If not, there is your fulcrum for the lever that is each end of the press. 

I am suprised you got a reading of 90#s though.


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## NMP (Aug 6, 2003)

Mr. Johnson, I am glad to see that you finally did the math on this. I will try not to nitpic but by using your picture and weight measurement on the strap I came up with a slightly different answer which is very close to my own findings during testing different designs in the past. Your example of a 50-50 split works just fine though. You have confirmed exactly what we have been trying to explain. That there is at least 80# of pressure exerted to the middle of the limb over a very narrow surface area. This is the number one concern with your design. If you can find a way of proving that there is no way this amount of pressure over this surface area being applied in the opposite direction can damage the outer limb material you will see a great increase in sales. Just for the record, I do like the overall design more than the other portable options.


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## ken Johnson (Apr 5, 2007)

*347# are a lot more then 90#*

In the following photo is of a Bowtech Guardian, notice its riser rests against the inside of the bow limb. This is no different then the rubber coated pin in the Nite Hawk Press. Notice also the contour of the limb, which is clamped between rubber bushings, does not change because of the riser. It stays the same thickness over the entire length of the limb. This allows the limb to flex evenly over its entire length.
If the Bowtech riser has no negative effect on the limb, then the rubber coated pin in the Nite Hawk Press should have even less effect on the limb, because it exerts much less pressure on the limb then the riser. Note the picture has arrows and number. The numbers are the # of pressure exerted at points along the limb. They are calculated using the, “Law of leavers”. With 180# of force at the axle and the pressure point of the press, the calculations are: at the riser 347#; at the coated pin 90#. 
Distance A / distance B * 180# = 347# The calculations are correct. 1.687 / .875 * 180# = 347#. The 180# and the 90# come from putting a bow scale in the strap of the NH Press and using the Law of Leavers to determine the force at the axles and the coated pin. Distance C / distance D * 180# = 90# , C is twice as long as D. Measurements were taken from a photo and the press. 
The Nite Hawk Press presses in a new way. By both pressing at the tips of the limbs and by floating on the limbs it reduces the pressure needed to press a bow. It simulates the actions of the cams and cables.
Look at the photo of the X-Force. Again using the law of leavers, Distance X / distance Y * 180# = 334#. 1.687 / .875 * 180# = 334# 
The Nite Hawk Press exerts only 90# to the limb to press the X-Force, yet all conventional presses use at least 334#. I say “at least”, because conventional presses clamp to the riser, which depending on the press and the set-up, adds even greater forces to the riser and the limbs. Since the Nite Hawk Press floats with the bow it uses only the force needed to press the bow, which is equal to the force the cams and cables apply to the limbs.
There is little risk of over pressing your bow with a Nite Hawk Press. It presses at the axle and not between the cams and the riser. This is so true of an X-Force & the Bowtech where the limbs flex to the axles. With a conventional press that flex must be removed from the limb by pressing the limbs until the end of the limb straitens out. The only way conventional press can do this is to over press the section of the limb between the riser and the point they are pressing against, note green line on photo. The Nite Hawk Press presses at the tips of the limbs, in the same way as the cams and cables. Therefore it does not allow any of the limb to relax, note limb in photo. The entire limb is pressed. The Nite Hawk Press is designed to simulate the actions of the cams and cables. Is there a better way of pressing a bow then to copy the normal actions of the bow? This is what the Nite Hawk Press is designed to do. 
To understand completely you should watch the video at www.nitehawkarchery.com .

Thank you.


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## ken Johnson (Apr 5, 2007)

*Difference*

Do you see the difference between a conventional press and the Nite Hawk?


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## ken Johnson (Apr 5, 2007)

*How a limb works*

When we consider how a limb works, what makes it spring back, it will give you more insight to why a Nite Hawk Press will not damage your bow limbs. Infact it is easier on you bow then any other press.

When at rest and the limbs are straight, the outside and the inside of a limb are the same length. As the limb is bent in a curve the outside becomes longer and the inside shorter.

The molecules on the out side of the limb are pulled apart and those on the inside are pushed together. The inside of the limb become harder and stronger while the outside becomes softer and weaker. This being the case, putting a small force against the inside of the limb will have less effect on a bent limb then applying the same force to the outside of the bent limb.

Those who would like you to believe applying a force to the inside of a bent limb would damage the limb have not done their homework. They have not given honest consideration to what really happens when a limb is bent. 

I hope this clears up any misleading theories you have read. 

Thank you.


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## danslaugenhoup (May 22, 2006)

*Great product!*

Have had the press for awhile now and use it often. Best one I have used yet. Nice to see it in Petersons Bowhunting Mag this past issue. If you need a press this is it. Last one you will need.

DS


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## NMP (Aug 6, 2003)

ken Johnson said:


> When we consider how a limb works, what makes it spring back, it will give you more insight to why a Nite Hawk Press will not damage your bow limbs. Infact it is easier on you bow then any other press.
> 
> When at rest and the limbs are straight, the outside and the inside of a limb are the same length. As the limb is bent in a curve the outside becomes longer and the inside shorter.
> 
> ...


No one has tried to mislead anyone here, why would we. If everyone went by your way of thinking about this being easier on the limbs than a real bowpress then everyone would just be pinning the cams to make cable changes because that is pretty much the same thing and you will not find a bow company that will recommend this. Sorry to have ruffled your feathers but these are things that needed to be addressed and I think that your explanations have helped you like I said they would earlier. I have done my homework on this subject and know what can and cannot happen here. Maybe the design characteristics and the laws of phisics will change someday to accomodate what you think is easier on limbs but for right now I only know of one set of bows that makes this statement true and those are the center pivots. I believe this to be an awesome deal for one of those Bowtechs.


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## stats75 (Dec 11, 2005)

i have acouple of questions, Is there force being applied to the backside of that limb by the pin? And if so what percentage of the force applied to the tip is created at the pin? 
My reason is this if you take a pencil and hold it like you are gonna break it, it looks alot like the same points of contact as in your press. 
Make a video to show actual pressure at these points, not in theory, but real world proof.


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## ken Johnson (Apr 5, 2007)

*Check out the video*

Go to www.nitehawkarchery.com A picture is worth a thousand words.


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## MegaDan (Jan 23, 2007)

*bow pressing*

you could have pressed that bow 20 times with the power press in the amount of time he did once, and the turn buckle, you'll have carple tunnel before u can say ouch!


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## danslaugenhoup (May 22, 2006)

*True*

True but the power press is $600 +. Most home users won't spend that much.
Lets compare apples to apples.


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## ken Johnson (Apr 5, 2007)

*Ease of use*

"The bow shop I mentioned is buying one for the shop and one for home. He was very impressed. He had a Bowtech he needed to replace limbs on but his shop press wouldn't work. I helped him set up the press and we changed the limbs. Last year he quit carrying PSEs because of the difficulty with pressing the bows.

My son and son in law were impressed." 

This was from a frist time buyer. As you can read he is enjoying his new press and the versitility it offers.


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## ken Johnson (Apr 5, 2007)

*Taking down your bow.*

This is an email I received from a new customer.

"The bow shop I mentioned is buying one for the shop and one for home. He was very impressed. He had a Bowtech he needed to replace limbs on but his shop press wouldn't work. I helped him set up the press and we changed the limbs. Last year he quit carrying PSEs because of the difficulty with pressing the bows."

"My son and son in law were impressed."

The Nite Hawk Press makes sceptics into believers because it works just as we say it does.


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## ken Johnson (Apr 5, 2007)

*it works great*

The bow shop I mentioned is buying one for the shop and one for home. He was very impressed. He had a Bowtech he needed to replace limbs on but his shop press wouldn't work. I helped him set up the press and we changed the limbs. Last year he quit carrying PSEs because of the difficulty with pressing the bows.


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## Karoojager (Dec 20, 2005)

Hello Ken,

Is it possible that you hawk press work on my Mathews Safari by 100# ?
If yes, please send one to me at Germany.
I saw the video and this hawk press is ideal for my several hunting trips to South Africa and Namibia.


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## Karoojager (Dec 20, 2005)

Hello Ken,

I got yesterday my bow press from you, at this way here I will say thank you.

First I was a bit sceptically how you bow press work especially at my Mathews Safari bow with 94# draw weight. After first using I am surprised how easy and simply the press works. I had no problem ( to much hand power ) to press my Safari hunting bow like with other mobile bow presses. Now you press is a standard tool by all my hunting trips to South Africa and Namibia in my bow case.

Congrates to this fine tool.

Frank Steinnagel

Germany


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## Theojt (May 18, 2005)

This discussion has been interesting. I am not a M.E. (isn't there someone on this board with a ME?) but it seems that the missing part of the discussion is the *distribution* of the forces across the limb. 

Logically it seems that drawing a bow distributes the force across the entire limb from riser bolt to cam axle. Conventional press would come close but not quite as good. These other types of portable presses seem to confine the majority of the force to a much, much smaller area of the limb.

Would love to see strain gauge results with placements at various positions up and down the limbs. That would resolve this question once and for all.

Jeff


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## Dewboy (Apr 19, 2005)

*I agree with Mr Johnson for the most part*

Although I'm not a Mechanical Engineer, I did start my college carrer as a Mechanical Engineering student. I don't even have to do the math here to point out that some of you are making a flawed assumptions The pin does put "pressure" on the limb, but because the entire length of the limb flexes, the force is applied over all of the limb beyond the riser. I'm not saying it's EVENLY applied. Most of the pressure is applied where the rubber coated bumpers rest against the limbs near the tips. Then, a fraction of this pressure is applied at the pins. 
I guess the argument is how much of a fraction of the weight applied to the strap is transferred to the pin. This is where you can make some wrong assumptions. assumming the screw holding the pin plate on is a pivot point or that the pin is a "Static" fulcrum is not correct(note key word STATIC!). If you try to use *Statics*(also known as Vector Mechanics) to solve this problem, you will come up with an innaccurate answer. This is a problem you would need to use the science of Dynamics, more specifically *Kinetics*, which is concerned with the motion of bodies under the action of forces.
Since the entire limb is bending(more and more the closer you get to the tips), You can't calculate the force at the pin as if the limb or fulcrum was static. The best way, unless you are a brillient Mechanical Engineer or physicist, would be to use a pressure switch to measure the pressure at the pin while at the same time using an inline scale to measure the tension on the strap. In fact, you wouldn't even need the inline scale since you are only concerned with the "ACTUAL" pressure at the pin.
Reylamb seems to have a beef with this press based on an understanding of high school Physics. "BUT", he does have a point based on another fact of Physics, "PRESSURE". Because of the very small area of contact the pin makes with the limb, the pressure is higher than it would be if it were a flat bar rather than a pin. This argument is valid.
So is this press doomed by Physics? Not even close! I just received mine and I love it! The one thing I would recommend is to go to the autoparts store and purchase some Vacuum hose to slide over the pins to spread the force of the pin against the limb! After my inspection of the Press, this was my only complaint. The shrink tubing around the pin just is NOT enough in my OPINION. Comparing the vacuum hose to the shrink tubing is like comparing a radial tire to an inner tube! 
I don't care if Pete Sheply himself says not to use the Night Hawk. I will use it unless he agrees to press my X-Force for me everytime I need to change strings or add a peep! It's not like I can put it between my legs and "SQUEEZE" til it collapses! Like Mr Johnson said, the PROOF is in the pudding! It works, and I didn't have to pay $300 OR MORE for a PSE certified bowpress to install a peep! And unless PSE takes the time to PROPERLY test it, they should not have anything negative to say about it. It is their choice whose press they test and OK, but I know how "Politics" can also be involved. The Night Hawk WORKS and it works GREAT! Can't beat it for the PRICE either!

Anthony Dew
Bowsmith, Gunsmith, CNC Machinist
(Jack of all trades, master of none!)


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