Really nice to see you do a backed bow, always love seeing your projects. I would HIGHLY advise AGAINST using Kevlar for a bow backing though, Kevlar is very strong and resistant to breaking when stressed, but only for a couple times like in a bullet-proof vest, it was never designed to be REPEATEDLY bend/stressed. Pretty much the only ones who use it for archery gear are the Japanese, they use it on some strings for yumi, and depending on the draw weight of the bow they usually break after 300-1000 shots. The Japanese use it because they want their string to fail after a couple hundred shots (supposed to be healthy for the yumi). Kevlar will break suddenly and without warning. Used as a bow backing it might hold up longer, but you should expect the kevlar backing on that bow to fail after 500-2000 shots or so. Fibreglass or carbon fibre is MUCH BETTER for a bow backing, it is much better suited for the repeated bending stresses on a bow.
Nice job. I'm working on an adjustable riser that i can vary the angle of the limbs and the distance between them. To find the optimal angle and weight for my bows
@@Helmbowman I'll send to a pic when it's done. It's made of metal two 2x2 cm square tubes welded together and then one fixed in place adjustable angle holder for one limb and a moveable adjustable angle for the other limb. The holders are just slot ins for the limbs
Hi friend, I’m good, and you? You can use kevlar fabric as bow backing but it will not work for entire bow, it is better to use fiberglass or carbon fabric
The numbers:kevlar has a tensile strength of ca 3000-3500 MPa, glasfibers between 3000-4500 based on subtype. So can be pretty similar. Please buy a chrono, I will contribute, really curious, how kevlar holds up in your bows. Pretty much an advanced bowmaker by now 👍, impressive precision. Glasfibers, carbonfibers, kevlar give longlasting waste at the end of their lifetime. I search for materials that can deteriorate at the end of life time but perform also well. I thought about using diatomes (natural silicium sand) with epoxy for the compression side and see how that performs. For the tension side, ancestors used sinew, I wonder if hair can substitute (a.e horse hair). I guess performance with organic materials will be lower as with modern materials, but may be not much.
Thanks for ideas! I’m also interested to try basalt fiber, it is something between glass and carbon in its properties… Natural materials can also be good performers, I’ve read in TBB about flax fibers, i will surely experiment with that
@@Helmbowman This Basaltfibers: Around the same tension strength as glasfiber. No Addons/chemicals in the production, So far no bad waste/toxicity report- around the same density..that sounds all awesome! I need to check this out- the back with basalt fiber and the belly with diatomite- that's then mostly sillicium oxid and epoxy plastic, that could be a good combo, with little toxic leftovers. Regarding Flax: Yes, seems to be pretty robust- in the range of 300MPa to 900MPa according one source- so pretty good but definitely not on the level with modern fibers- but if you combine it with Epoxy, it might be again a different game..Thanks for the hint!
@@Helmbowman And may be you take Chitosan on your tracking list as well- it's the material in insect shell, and there's lot's of research going on for all kind of composite materials. It's not strong by default, but in combination and the right shape- microsphere, fiber, honeycomb- it could have a high potential as well, and is biodegradable
Really nice to see you do a backed bow, always love seeing your projects. I would HIGHLY advise AGAINST using Kevlar for a bow backing though, Kevlar is very strong and resistant to breaking when stressed, but only for a couple times like in a bullet-proof vest, it was never designed to be REPEATEDLY bend/stressed. Pretty much the only ones who use it for archery gear are the Japanese, they use it on some strings for yumi, and depending on the draw weight of the bow they usually break after 300-1000 shots. The Japanese use it because they want their string to fail after a couple hundred shots (supposed to be healthy for the yumi). Kevlar will break suddenly and without warning. Used as a bow backing it might hold up longer, but you should expect the kevlar backing on that bow to fail after 500-2000 shots or so. Fibreglass or carbon fibre is MUCH BETTER for a bow backing, it is much better suited for the repeated bending stresses on a bow.
Yes, this is experiment, so we will see how long it will hold, thanks for watching friend!
Another really cool bow. Keep the content coming brother. Nice work
Thanks a lot bro! 💪🏻
Woooooow👌👍 this is an awesome build.
Thanks a lot bro!!
Nice job. I'm working on an adjustable riser that i can vary the angle of the limbs and the distance between them. To find the optimal angle and weight for my bows
Thats interesting! How you will do that? I usually make few wooden riser, and loose a lot of time, it would be very useful to have adjustable one
@@Helmbowman I'll send to a pic when it's done. It's made of metal two 2x2 cm square tubes welded together and then one fixed in place adjustable angle holder for one limb and a moveable adjustable angle for the other limb. The holders are just slot ins for the limbs
@jarchdm genius idea! Thanks!
Muy bueno lindo arco para,la caza
Thanks brother!
Hila friend, how are you? Greetings from Colombia, friend, can a bow be made with Kevlar fabric?
Hi friend, I’m good, and you? You can use kevlar fabric as bow backing but it will not work for entire bow, it is better to use fiberglass or carbon fabric
The numbers:kevlar has a tensile strength of ca 3000-3500 MPa, glasfibers between 3000-4500 based on subtype. So can be pretty similar.
Please buy a chrono, I will contribute, really curious, how kevlar holds up in your bows.
Pretty much an advanced bowmaker by now 👍, impressive precision.
Glasfibers, carbonfibers, kevlar give longlasting waste at the end of their lifetime.
I search for materials that can deteriorate at the end of life time but perform also well.
I thought about using diatomes (natural silicium sand) with epoxy for the compression side and see how that performs.
For the tension side, ancestors used sinew, I wonder if hair can substitute (a.e horse hair).
I guess performance with organic materials will be lower as with modern materials, but may be not much.
Thanks for ideas! I’m also interested to try basalt fiber, it is something between glass and carbon in its properties… Natural materials can also be good performers, I’ve read in TBB about flax fibers, i will surely experiment with that
@@Helmbowman This Basaltfibers: Around the same tension strength as glasfiber. No Addons/chemicals in the production, So far no bad waste/toxicity report- around the same density..that sounds all awesome! I need to check this out- the back with basalt fiber and the belly with diatomite- that's then mostly sillicium oxid and epoxy plastic, that could be a good combo, with little toxic leftovers. Regarding Flax: Yes, seems to be pretty robust- in the range of 300MPa to 900MPa according one source- so pretty good but definitely not on the level with modern fibers- but if you combine it with Epoxy, it might be again a different game..Thanks for the hint!
@recursr1892 That diatomite sounds interesting, i will check that out, thanks friend!
@@Helmbowman And may be you take Chitosan on your tracking list as well- it's the material in insect shell, and there's lot's of research going on for all kind of composite materials. It's not strong by default, but in combination and the right shape- microsphere, fiber, honeycomb- it could have a high potential as well, and is biodegradable
@recursr1892 I will research that surely! Thanks!
Muy bueno
Very nice!
Thanks a lot!
Looks like fiberglass
Its similar in looks, just yellow, but pretty difficult to grind and sand
Hi, i ha e some cherry wood and carbon fiber. Can they works good together?
Yes! Cherry is really good in compression, weak in tension, but when you back it with carbon i think it will be great combo