Questions about crossbows and maces
Hi gentlemen, i have some questions first about the crossbows.
my mind is a little confused about the making of crossbows the question is would it be possible to take a leafspring as the bow? Wouldn't it be tough for men to pull the string to ready the crossbow?

second: the maces

i was thinking about making a mace with a wooden haft is someone on this site made a project like this who could help me telling his/her impressions about the subject and show me some pictures of their maces project?
Re: Questions about crossbows and maces
Etienne Hamel wrote:
Hi gentlemen, i have some questions first about the crossbows.
my mind is a little confused about the making of crossbows the question is would it be possible to take a leafspring as the bow? Wouldn't it be tough for men to pull the string to ready the crossbow?

second: the maces

i was thinking about making a mace with a wooden haft is someone on this site made a project like this who could help me telling his/her impressions about the subject and show me some pictures of their maces project?


Can't talk to your mace question, but I have a little insight into your crossbow question. In theory (note emphasis) one could use a leaf spring as the basis for a crossbow prodd. I *think* I've even heard about something like that being done, and it sorta worked. There are some practical problems:

1. The draw weight would be impressive - several hundred pounds, I should think. And, no, one could not possibly span that by hand. The practical upper limit for using a stirrup and both hands is, I believe, in the ~200 lbs. or so range. From there and up to 350 lbs. one needs a Goat's Foot lever. Past that the solutions become more drastic, usually a windlass or cranequin. See European Crossbows: A Survey by Josuf Ulm for more details.

2. Most leafsprings are rather used. I would fear fracture or outright failure in attempting to use one as a prodd.

3. Shaping the bow would be a pain, since you would need to work very slowly to avoid ruining the temper. And even then you would not be able to fully shape it the way it needs to be without forging it (I'm thinking the ends, in particular). I would hate to try and temper such a thing in my forge - it would have to be professionally done.

In general, building really heavy crossbows is difficult. I remember a friend of mine, Kurt Suleski, who was trying to build a mere 300 lb. or so bow, and he had a lot of problems finding a maker who could construct a strong prodd that wouldn't take a set. If I recall correctly, he even approached the Amish (who have experience making their own wagon and carriage springs) to make a proper prodd. There was one fellow who advertised prodds up to 800 lbs (and could build heavier but did not recommend it for safety reasons) but his website has disappeared and with it that business. I personally would have loved to build an 800 lb. crossbow with a cranequin just as a fine example of early technology, and perhaps to do a few controlled armour penetration tests.
Etienne,

As far as if you can use a leaf spring for a bow.... Yes I think generally speaking sounds like it should work fine. In period it was hard so not much change. The steel bows appear not to have been spanned by hand.

As far as draw weights. composite bows can easily be about perhaps 770 lbs and steel bows can get to around 1000 no problem. That said the average is a bit harder to arrive at. I doubt very much a crossbow is for military use much under 350 or 450 lbs. I also figure one can span a bow fairly easily in this range of 300-400 or so with the belt hook method of spanning.... heck I leg lifted 600 lbs pounds plus no problem for years... could do well more than half of that on one leg. The issue is that once you get toward 400-700 plus I think you likely are getting to a place the average person would need more than leg/back muscle power. ;) There are several methods used. (I should add this was not 600 lb crossbow but weight lifted on leg pushes).

Windlass-
http://en.wikipedia.org/wiki/Image:Armborst_4...ljebok.png

Reduction gear-
http://en.wikipedia.org/wiki/Image:Armborst_3...ljebok.png

Goats foot-
http://en.wikipedia.org/wiki/Image:Armborst_1...ljebok.png

The first two can handle huge draw weights. The Goat's foot not so much but around and more than the belt hook.

There were also bigger crossbows, Great crossbows getting up to 2600lbs and the smaller two foot crossbows about 1600-1700lbs. These both tend to be siege weapons weighing much more than their smaller crossbow cousins.

Most of this info can be found in Payne Galloways Crossbow and Jean Leibel's springalds and great crossbows

As far as maces go. What period are you wanting? Norman era ones have much smaller heads with little bumps on them almost always by the looks of things with wood handles. Later ones likely did have them as well. but the heads become more substancial. What are your questions specifically?

RPM


Last edited by Randall Moffett on Wed 05 Nov, 2008 11:06 pm; edited 1 time in total
thanks for the info, and for the mace i would probably go for the 13th century english (maybe ill do a replica like the one on this link )
http://otlichnik.tripod.com/medmace3.html
I'm also interested in making a medieval crossbow someday. When I do, I'll probably buy the prod (the bow part) from Alchem.

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

The prices seem excellent. They have prods up to 250 lb. and all the other parts one needs--strings, nuts, levers, etc-- plus free online plans for the tiller (stock). I'll probably use their plans as a general guide but otherwise look to documented originals or examples in artwork. Here's a link to their plan: http://www.alcheminc.com/plan.gif
If I were to get a crossbow together I'd not bother with anything lower than 350-400. Part is that I'd like to see what a real war crossbow could do. 250lbs just seems too low, though perhaps fine for show and playing around with. The museum I worked at had a few nice 16th-17th century ones with steel prods.... looked like leaf springs on a truck. Very thick and hefty. I can see why they lasted so long... There are a few people over hear that make prods of 400 plus draw but I need to get a decent mail shirt first....

RPM
The first bow I ever made used a leaf spring that was cut down and also thinned to taper it down and tiller it to something about right. If you pick a nice looking spring and don't treat it badly during the grinding and the cutting it should be fine. Cross bow prods are tempered very high at about 400 degrees C (don't know the Farenheight) but way beyond a knife or a sword, so you would have to get it really hot to mess the temper up.

Bear in mind that a leaf spring is deflected very little when you put a string on it and draw the string back a modest amount so even a spring you can't bend at all by hand can be used when strung.

You can cut it the nocks on the end with a grinder and red hot bend them if you wish, as the bow tips are not really stressed and it will work fine.

As a rough guide a bow 40mm wide by 9mm thick and 620 mm long and tapered slightly will give about 220-260lb at about 130mm draw

I have a monster here that is 800lb and is 48mm x 15mm x 720mm also geared for 130mm draw.

For a stirrup bow with no spanning device 250lb is the max for most people and even a bit under, a goats foot will easily manage 350lb and cranequin or windlass will need to be used above this. I have personally not used a belt and claw, but I would think that 300lb would be top for most, but you could double this with the compound type that used a pulley wheel in the system and that is an easy thing to make.

If it fractures you are in big trouble, so If I were you, I would make the bow from a leaf spring and then get it retempered as if it were a leaf spring - basically the same thing as a prod, but have it done at a spring makers. If the retempering cost you more than 40$ I would be surprised.

Failing that buy one from Alchem.

Have fun

Tod
In this litigious age I forgot to spell out in a very clear way the following.

If I were to go about making a crossbow using an old leaf spring then the previous points I made, would be points I would consider; however I would in no way recommend another person to make a bow using an old leaf spring and nor would I encourage it.
Re: Questions about crossbows and maces
C. Gadda wrote:
Etienne Hamel wrote:
Hi gentlemen, i have some questions first about the crossbows.
my mind is a little confused about the making of crossbows the question is would it be possible to take a leafspring as the bow? Wouldn't it be tough for men to pull the string to ready the crossbow?

second: the maces

i was thinking about making a mace with a wooden haft is someone on this site made a project like this who could help me telling his/her impressions about the subject and show me some pictures of their maces project?


Can't talk to your mace question, but I have a little insight into your crossbow question. In theory (note emphasis) one could use a leaf spring as the basis for a crossbow prodd. I *think* I've even heard about something like that being done, and it sorta worked. There are some practical problems:

1. The draw weight would be impressive - several hundred pounds, I should think. And, no, one could not possibly span that by hand. The practical upper limit for using a stirrup and both hands is, I believe, in the ~200 lbs. or so range. From there and up to 350 lbs. one needs a Goat's Foot lever. Past that the solutions become more drastic, usually a windlass or cranequin. See European Crossbows: A Survey by Josuf Ulm for more details.

2. Most leafsprings are rather used. I would fear fracture or outright failure in attempting to use one as a prodd.

3. Shaping the bow would be a pain, since you would need to work very slowly to avoid ruining the temper. And even then you would not be able to fully shape it the way it needs to be without forging it (I'm thinking the ends, in particular). I would hate to try and temper such a thing in my forge - it would have to be professionally done.

In general, building really heavy crossbows is difficult. I remember a friend of mine, Kurt Suleski, who was trying to build a mere 300 lb. or so bow, and he had a lot of problems finding a maker who could construct a strong prodd that wouldn't take a set. If I recall correctly, he even approached the Amish (who have experience making their own wagon and carriage springs) to make a proper prodd. There was one fellow who advertised prodds up to 800 lbs (and could build heavier but did not recommend it for safety reasons) but his website has disappeared and with it that business. I personally would have loved to build an 800 lb. crossbow with a cranequin just as a fine example of early technology, and perhaps to do a few controlled armour penetration tests.



About Kurt Suleski, he had a great page and a great article about making medieval crossbows.
About a year ago I tried to open his page but it didn't work so i contacted him through email and he gave me a new link, now the new page doesn't work neither his email, if anybody has any information or a link (to his page or an article about crossbows, if someone saved it to a file) please paste
after some searching i found the page

http://www.stormthewalls.kicks-ass.net/
Stefan L wrote:
after some searching i found the page

http://www.stormthewalls.kicks-ass.net/



now this page doesn't work anymore, i have such problems with it, twice i completely downloaded it and 2 of my HDs died

I need that page, if anyone has it or know any new link for it or knows kurts email please reply
I have an old ( circa 1955) Popular Mechanics Do-It-Yourself Encyclopedia which has plans to make either a wood prod or steel prod crossbow.

The article has a chart which states that a steel prod crossbow made from a 1/4" thick leaf spring that is 1 1/2" wide will have a draw weight of 438 pounds. The article suggests that it will take two hacksaw blades to cut the leaf spring to shape and also instructs the builder to rivet plastic nocks to the steel prod. I have images of rivets and plastic flying off at warp speed propelled by the power of a 400 pound plus draw weight steel bow.

Leo was careful to make it clear that he was not advocating that anybody attempt to make a steel prod cross bow, I know that if I chose to make one I would look for a better source than this for plans; these look sketchy if not downright dangerous.
Hello,

As an addendum: there is a period method to reducing the danger from catastrophic failure of the prod. Cover it in parchment. This was glued on and painted on many crossbows. And serves the dual function of decoration and reducing the severity of the fail state.

Cheers,
Steven

P.S. When I'm too old to swing a sword for fighting I'm gonna take up medieval crossbow archery.
Ken Speed wrote
Quote:
The article has a chart which states that a steel prod crossbow made from a 1/4" thick leaf spring that is 1 1/2" wide will have a draw weight of 438 pounds. The article suggests that it will take two hacksaw blades to cut the leaf spring to shape and also instructs the builder to rivet plastic nocks to the steel prod. I have images of rivets and plastic flying off at warp speed propelled by the power of a 400 pound plus draw weight steel bow.


I love old books like this as they are completly fascinating but for the record I would expect those dimensions on a 24" wide bow (which is pretty normal) to produce about 160lb at 4 1/2" (which is a pretty normal draw) and 210lbs at 5 1/4" which is the high end of normal draw length. if it was a 3/8" spring then I would be thinking about the 350-400lb mark.

Steven H wrote
Quote:
As an addendum: there is a period method to reducing the danger from catastrophic failure of the prod. Cover it in parchment. This was glued on and painted on many crossbows. And serves the dual function of decoration and reducing the severity of the fail state.


I think parchment wrapping was quite rare but it would serve this purpose, but I am not sure quite how much. I have never yet had a failed bow so I am unsure of how they did fail. That said many many bows in museums do not have the original bow and have repaired stocks so failure was a constant possibility and the usual way of dealing with bow failure was to have a bundle of thick cords running between the bow tips and lashed at each end and the middle of the bow and sometimes at the mid points of the limbs and this is very often seen in representations and in museums. Again I am not sure if this would entirely save you, but I guess anything is better than nothing.

Tod
Leo commented,

"I love old books like this as they are completly fascinating but for the record I would expect those dimensions on a 24" wide bow (which is pretty normal) to produce about 160lb at 4 1/2" (which is a pretty normal draw) and 210lbs at 5 1/4" which is the high end of normal draw length. if it was a 3/8" spring then I would be thinking about the 350-400lb mark."

Leo, whatever you say. This set of books, looked at with today's sensibilities, is somewhere between horrifying and hysterically funny. I swear they have an article about making a blast furnace from a clothes iron. When I read it I had a mental image of postwar houses spontaneously combusting all across the country! I've never been able to decide if that article is crazier than the one which instructs the reader how to make a ski sled for his children out of iron pipe. Ta Ta Kids!

I also enjoy the fact that the demonstrator for the photo is ALWAYS wearing a tie no matter what kind of machine he's operating.
I definitely think making a crossbow from a leaf spring would work. My uncle told me when he was growing up in the U.P. that people would do just that sort of thing with a junked car. They were powerful enough to put a bolt through a 1" thick piece of Oak at a reasonable distance. I can't be sure, but I think he said the police up there got so worried about this practice that they made leaf spring bows illegal.

I would personally say give it a whirl, you'll never know if it doesn't work if you don't try.
Hello, i see this thread has been dead for a couple of years, but i wonder how folks have fared on making a leaf spring crossbow prod?

I am planning on making a leaf spring crossbow prod as well. However, appreciating how much power can be stored in that spring, i am buying mine brand new. Looking over a good number of sizes, unless you want to start looking at 42"+ tractor trtrailorprings, it seems that the best ones are probably the double eyed 30" trtrailoreaf spring, 1&3/4" wide.

It already has the length & curve to almost the exact same pitch as the medieval crossbow prod plans in Sir Ralph Payne-Gallwey's book, & is flat on its belly.

Also quite convenient, the eye loops at either end seem quite well suited for holding a stout bowstring with a little modification.

One challenge i can foresee with the leaf spring prod though is that unless i want to shave an extra 1/4" off the width of the prod (which i don't), i will need to compensate for this by grading the stock.

Anyway, i will try to keep yall informed as my work progresses. I have a garden, orchard, mushrooms & alpacas to tend to as well, so this will be a long term project.

Take care ; P

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