i have been making simple traditional crossbows for a while out of bamboo but now i am trying to make a modernized version but i wont make it compound so that it can still remain a bit more true to the original but i just need to know what to make the limbs of the crossbow out of i was thinking fiber glass but if there was even a small fracture on it my high tension string is gonna snap back at me i was gonna go aluminum but aluminum doesn't go back to its original form so it won't spring back to its original form it will just be a bended thing so what material should i use? i already ruled out wood cos that will just make it into a traditional crossbow again

I would go with fiber glass laminated with contact cement. You can get tension rods for chain link fences at home depot very cheap. They are a bit narrow but you can make a workable bow. Aussie is right if you play around with a lot of power, a string or bow break can be very dangerous. How do you plan to make the trigger this is always the bigger problem?

Markmyster wrote on Mar 23^rd, 2009 at 7:07am:


As a professional fencer I would highly recommend against using these. They are really not very strong, even if you stacked and welded several together.

wellslung wrote on Mar 23^rd, 2009 at 1:37pm:


Sorry I should have said fiberglass tensor rods. I take by your use of the word welded that you thought I was refering to steel.

I did a lot of research on this last year when I was making a prototype.   I made a wooden (oak) bow using standard bow-making technique and backed it with silk.  Only pulled about 50 pounds.

There's an awful lot of "just use an auto leaf spring" stuff on the web, but almost nothing about anyone who has actually done this.   Leaf springs are not "tillered" (tapered) the way a bow (the actual term for a crossbow is "prod") is, and as they are made they would be very inefficient.
The material is OK, but you would have to do a great deal of cutting, grinding, and shaping, and then have the entire thing re-tempered.  It must be "spring tempered", of course.

Much easier just to buy a pre-made prod from a firm like Alchem:

http://www.alcheminc.com/crossbow.html

Which specializes in medieval crossbow parts.

Fiberglass is very tricky to work with.  You could conceivably make a wooden bow and apply standard bow laminates of fiberglass, but this requires special adhesives and must be "cured" as well.

Were I going to make a functional medieval crossbow, I think I'd just buy the prod from Alchem.

Markmyster wrote on Mar 23^rd, 2009 at 8:19pm:

Oops yeah I did. A warning about those though is they get worn down very easy and can make your arms very itchy when they do. I'm not a huge fan of PPE so little things like that tend to get me

These are nice, with the bonus that you can use the same ammo for your sling.

http://www.todsstuff.co.uk/stonebows.php

Have a look at the rest of the site. I have seen some of his stuff up close and he is a real craftsman. His sling was a bit poor though!

hummm i am having a hard time finding a leaf spring and i right now already have all of the parts for my crossbow

1.My stock
2.my trigger mechanisim (already in a housing)

i decided to separate the trigger system from the stock itself for easy maintenance and if i do need to make it
a one piece trigger system (incorporated already into the main body of the crossbow) i just take the trigger housing out and put in my integrated one

so far my only problem right now is just my crossbow limbs i have decided already to just go wood since like i mentioned earlier leaf springs are hard to come by but than switching to wood creates another problem since the measurements i have right now for limbs are for steel limbs and limbs made for traditional crossbows (the length of my traditional crossbows differs greatly as the length of mine is based on the length of a store bought one) the wood i am gonna use is Bamboo if anyone here knows the measurements i need please do tell i searched the internet but the measurements are for other types of wood and since i live in a tropical area bamboo is the only wood here that have he properties of cherry wood or yew and is cheap and readily available