Crossbow prod question

[Mububban]

Well 2 questions really.

I know most of us here use trad bows, but was wondering if anyone knew if the same basic principles for making and tillering bows apply to crossbow prods?

With the guidance of my bowmaking friend, we've been experimenting with using vertical bamboo flooring as a cheap intro into making bows. We got halfway through 2 bows before Christmas and we're booked in for the end of March to try and finish them.

Question 1 - as I said, do the same basic principles for making and tillering bows apply to crossbow prods or are they made in an entirely different way?

Quiestion 2, from a friend who's interested in learning bowmaking and has a crossbow in need of a prod -
You are already making your bamboo bows by gluing together two layers.
How about, instead of two bamboo strips you used one bamboo and one spotted gum, or one bamboo and one jarrah, or ….
ie use the bamboo in tension, the other timber (eg a hardwood) in compression.


The idea is that seeing as it's hard to find decent cheap adult sized bows under 30lb for use in combat archery, the bamboo may prove a good cheap way to making a bow in the 23-30lb range. Most people balk at paying even $150 for a second hand recurve or longbow seeing as we only play combat archery maybe 6 times a year if lucky.

I've heard that bamboo flooring is prone to taking a set, thus losing poundage. As long as it stays above say 23lb, and below 30lb, we don't mind, especially for the price. And the same applies for crossbow prods. We have a 600 inch-pound limit which can be reached from any combination of poundage x draw length = less than or equal to 600 inch pounds.

Has anyone ever experimented with making a trad crossbow? If so any advice would be greatly appreciated as a second project after the bows get made.

[nimrod]

mate have not made a wooden prod but if you can find a copy of ( the book of the crossbow ) by Ralph Payne-Gallwey you may find the info you are looking for if I can find a spare hour or 2 will look through my copy cheers hugh.

[archangel]

Mububban

Good to hear you are still working on your combat bows using the flooring boards. There's no reason why bamboo laminated with timber wouldn't make a decent prod. The Chinese crossbows were a good example. http://www.atarn.org/chinese/rept_xbow.htm

The effective range of these Chinese weapons was about 80 yards; their extreme range from 180 to 200 yards. The bamboo arrows, though short and light, were well made and had steel heads that were heavy in proportion to the length of their shafts. They had no feathers, so that their freedom of movement might not be impeded as they dropped one by one from the magazine when the crossbow was being used. The bow was made either of one stout piece of male bamboo, about 3 ft. 6 in. long, or of several flat strips lashed together. In the latter case, the bow-string passed through a hole in each end of the bow, fig. 174. The bow-string consisted of animal sinew twisted into a cord of suitable strength.

I'm not sure about using jarrah but spotted gum certainly sounds interesting if you can get hold of some. Are you thinking an asian recurved/static tip or european straight limbed design? what sort of weight range? I have some american ash that may work - having a previous interest in reproduction crossbows, give me a few weeks and I'll see what can be done.

[looseplucker]

There is a book re Crossbows by Frank Bilson, if you can get it, which shows how to make a prod - I also have a 'self sufficiency' book with similar plans in.

[greybeard]

Hi,
It may be worthwile getting in touch with Cliff Turpin, (Turbow). He makes reproductions of medieval crossbows. I believe he holds an armourers licence to comply with Queensland legislation.
Daryl.

[perry]

I have made several of my own crossbows before the BS licensing arrangements came into Qld law and am a licenced owner . Any of the woods or techniques that make selfbows or laminated bows are suitable for prods . The main clue is to make them a minimum of 3 times the drawlength of the crossbow if they are laminated or not . If the prod is to be of a heavy drawweight I would make it 3 1/2 times the drawlength
Cliff has made light prods from strips of bamboo that performed poorly but were adequete for demonstration purposes as well as prods up to 200 plus pound draw from spottedgum and other woods such as american ash. As a footnote in Qld it is not illegal to make crossbow prods but it is illegal to make the stock without an armourers license , more proof that crossbows are just a short bow on a stick . regards Perry

[Mububban]

Thanks for the info guys, I'll pass it on to my friends.

David, it's for combat archery mainly so it's got to equal or be under 600 inch pounds ie draw weight in pounds x bolt draw length in inches = total inch pounds. To shoot at each other it's got to be on or under 600.

The crossbows in use in our group are all Turbows and the European straight limb design, made on one type of timber and backed with glass. We've had a few crack over the years. We'd just like to try and do it ourselves as another skill set to add to the group, but if we fail horribly we can always contact Cliff Turpin I suppose

[longbow steve]

Hi, thought you might be interested in photos of a cross bow prod?? I mean short recurve I scored from a lady who had a recurve for sale a while back, it appears to be hickory, deflexed, recurved tips following one growth ring, 35 inches ntn 13/4 wide down to 3/4 at the tips.
Have you considered using T/d recurv limbs on a small mount?

[archangel]

Mub

PM sent off to your friend. Sounds like a good project and will hear from him in due course.

it's got to equal or be under 600 inch pounds ie draw weight in pounds x bolt draw length in inches = total inch pounds. To shoot at each other it's got to be on or under 600.

If my maths is correct, with a 10" bolt, the bow weight must be no more than 60lb ... that's still a fair bit of force behind the bolt! I presume they are blunt tipped, but what's it like getting whacked in the rear with one of these?

[Mububban]

We've only got one crossbow that sees regular action on the combat field, I think it's a fair bit under the 600 inch pound limit from memory.

Certainly the shorter bolt has less mass thus momentum, blocking a bolt on my arm shield is much lighter compared to the hits from an almost 30lb recurve or longbow. They make much more of a high pitched "tack" sound when they hit the shield rather than an arrow which makes a "thock" sound.

The bolts tends to really zip off the deck but lose speed quickly, due to the shorter stroke/cast of the crossbow string perhaps? The user nromally hides behind the fort and sits, cocked and waiting, to provide covering fire for the archers and infantry as they move around the field. You can never take your eyes off the fort because you know he's always loaded.......

Steve, I'll try and get some photos this weekend of the Turbow crossbow in question, or one similar.

[archangel]

Started work on a 'traditional crossbow'. I appreciate that modern crossbows don't hold much interest for the average trad archer but this thread has got my attention. The design for the stock and roller/trigger has come from the net: I've used a dense NZ hardwood rewarewa for the roller, the piece of brass rod will form the centre pin and will be trimmed to size eventually. The stock will be cut from an oregon post in two halves, so the trigger recess can be accessed.

I will be making a bamboo/timber prod, but am also playing with the limbs from my failed horsebow to design a centre-shot bow. The two limbs will be mounted into a housing on either side of the stock and the bolts will be shot through the gap.