Hello from Virginia

Just wanted to say 'hello' - I've been looking at the forum for a few days, after deciding to attempt to make a medival style crossbow. I've been working wood for a good while now, and making knives for almost a year - this crossbow thing is proving to be quite a challenge! Seems like a very friendly place here - looking forward to having fun and learning much. Mike

Hi Mike,

Welcome to the board.

Tell us a little more about your ideas.  What kind of xbow are you  thinking about?  What do you think your main purpose would be i.e. target shooting, hunting, re-enactment etc.

There are experienced builders here in all of these areas that will be happy to give feed back. 

All the best Ernest (Hotspur)

Hotspur - I'm mostly interested in making a target bow - don't hunt anymore. I've got a one piece walnut stock started, a round lock of blackwood, and a trigger mechanism out of steel. I would like to ask - is the 'tickler' supposed to be loose, ie, able to wiggle from side to side, or is it somehow held in place? My trigger is also a little sticky - may not have the wheel/trigger mating surfaces right. I'm having trouble with the prod - have tried bending wood, with 3 failures - I have one solid 1" thick by 2" piece of walnut that I steam bent in a form - don't know if it has enough bend, but at least this one didn't snap. Also made 3 bolts of quarter-sawn white oak with steel tips. Any advice would be greatly appreciated.

Walnut's probably not your best choice for a wooden prod.  Ash, Red Elm, Hickory, Osage, all have been modulus of elasticity (springiness) for making bows.  You might want to consider a loose laminate prod, composed of several thin (.06 - .10) strips of wood about 1-1.25" wide and of varying lengths loosely held together like an old fashioned leaf spring.  The advantage of a loose laminate is that you can easily increase/decrease power by adding/removing laminations without spending a lot of time carving or steaming, etc. a prod only to have it fail on you...

A tickler is a long arm that is a 'sear' held against the nut at one end, attached by a pivot pin to the tiller, which then becomes the firing lever/trigger paralleling the bottom edge of the tiller.  Sounds like, if you have both a "trigger" and a tickler that we need to see a picture of this action.

I cast a vote for hickory as a prod wood.  It is very forgiving of the sorts of mistakes we all make on our first attempts.  It also steam bends pretty well.

Also, reading the "Traditional Boyer's Bible" books will give you everything you need to know about wooden bows.  They don't deal with crossbows at all, but the information still applies.  http://www.amazon.com/The-Traditional-Bowyers-Bible-Volume/dp/1585740853

Mac

I snapped my latest steam-bent walnut prod (it was air dried from a tree I had a fellow cut up for me from a large tree that came down - he has a portable sawmill biz). Does the hickory you are talking about have to be air or kiln dried, or does it matter? I'll get a pic up soon - I probably have my terminology wrong on the 'tickler', etc. I may just buy a metal prod from a site I found online. I'm curious - were all medieval era crossbow stocks of one piece, or were some two piece, laminated, or other? Thanks. Talk to you all soon, Mike

Hickory can be air or kiln dried; but air dried is better if you can find it.  Many of the metal prod providers have hugely long wait times and often poor service... read some of the complaints here!  Nothing wrong with wood prods, but there are ways... and then there are ways... to work that wood.  As I mentioned before, several thin pieces have numerous advantages.  If that "look" bothers you, the prod can always be covered by thin leather.

IIRC most true medieval tillers (stocks) were carved from a single piece of wood.  Nothing wrong with laminating up two or three pieces though.  That can certainly make assembling an action much easier.  There aren't an Authenticity Police here.  If it looks good, that's what matters.

If you want a good metal prod at a reasonable price I recommend ordering from slobows:


http://shop.slobowscrossbows.com/

It is advisable to start with a prod before you build as you need to know the draw length and brace hight as these will dictate the tiller dims.

I think the Alchem plan is a good starting point to show basic geometry (adjust for whatever prod you get) link below.  I can't recommend ordering from Alchem from personal experience as the wait times are measured in glacial cycles:

http://www.alcheminc.com/plan.gif

kenh wrote:
IIRC most true medieval tillers (stocks) were carved from a single piece of wood.  Nothing wrong with laminating up two or three pieces though.  That can certainly make assembling an action much easier.  There aren't an Authenticity Police here.  If it looks good, that's what matters.

I might be the closest thing we have here to a Medieval Authenticity Policeman  (Unless Geezer is an undercover cop)   

I do not know of any historical examples of laminated tillers, but as Kenh says, as long as it looks right, who cares how it was assembled.  Do what you got to do to get the results you want.  If you worry too much about whether you are doing it "right" you might never get anything done.  If you end up feeling "dirty" about how you did it, you can try something different the next time.

As far as I can tell, there is no one making any medieval object of any sort in exactly the same way the originals were made.  We can't, really.  What's important (to me, anyway) is that it looks, feels,  and works like the real thing.  That's the best we can hope for, and that's difficult enough without worrying how you got there.

Detective Sargent Mac

My slowbow prod arrived within a fortnight. Givin I asked for a specific draw weight, that isn't bad. I'm in Il, and it shipped from Ohio

I agree completely with Hotspur.Whenever you want to build something,you need a starting,or datum point,something that everything else relates to,either dimensionally,or by application.With a crossbow,that is the prod,it dictates just about everything to do with the tiller,or stock.When you have sorted out how much you want to spend,and how much you want to do yourself,then you need to look at options and availability.
                                            There has been,and I'm sure will continue to be,many postings concerning prods and prod materials.Just about anything will work,be it wood,metal,fibreglass or P.V.C.
but obviously,some will work better than others.Fibreglass is generally considered to be the best material for it's availability,price,and working characteristics,although those who favour steel prods would probably disagree.Fibreglass prods are readily available on E Bay,and through archery suppliers,and are probably the best way for a beginning constructor to go,metal prods seem to take longer to get hold of.
                           You can of course make your own prod,but doing so will require a lot of research,experimentation,and at the finish may not provide a product that satisfies you.I,and I suspect many other forum members would not recommend that a first time constructor go this route.Many forum members do build their own prods,but usually not until they have at least one build under their belts,or have copied a design from a successful build from the forum.
                                                If you are going to build a crossbow,the best thing you can do,is read all the forum archived postings,and go to you tube and watch videos on home made crossbows.Doing so will show you what is possible,and help you decide which direction you want to go in.Good luck with your build.
                                       Hermit.

I have finished my first crossbow. Got a prod and string from Alchem, a 125 pound draw weight steel model. I decided to do away with my initial attempt at a one piece tiller, and, using a plan on Alchem's website as a guide, made mine of a two-piece cherry laminate with some birds-eye maple veneer on top, and blackwood dowels. Oh, and I made three bolts out of white oak with turned, steel points. I have four pics uploaded here onto my "personal gallery" - can you see those images? I shot it twice today, works - but I'm a little concerned - the string only slightly bends the prod, like only an inch or so - I expected much more "bowing" of the prod. Critique me, please. Mike

On my big crossbow, the bow ends only move a couple inches at 11.5" draw. it is an Alchem 125# too.
If you think of the trig behind what is going on, it makes sense.

Hi, and thanks for replying. I meant when at rest, the string and prod are almost in a straight line - I expected the prod to be bent, when at rest. Am I wrong in thinking so? I'm fine with that - if it is correct, I'll be thrilled. Mike

The tips of a prod; especially a steel prod, will not move much. Certainly not like the tips of a longbow or horsebow....

You say your prod is from Alchem,I am presuming that the string you used is one recommended by them,
and your brace height and draw length is as specified for your particular bow.If this is the case,then your limb movement will be as it should.Steel does not have the flexibility of wood,fibreglass,or wood/fibreglass composites.
                                   Hermit.

Hermit - yes, the prod and string were both ordered from Alchem, arrived in about 11 days after ordering. I used Alchem's plan for the front of the tiller, dimensions should be as their diagram - I made changes to the 'back of the crossbow plan. But I have, like, an 11 draw instead of the 8 1/2 or so they say one will get. Hmmm. Think I'll have to make my bolts a little lighter (1/2" no taper currently) - will try 3/8" and tapered toward the front - maybe aluminum instead of steel point - and bigger wood fletching. Actually had to have a friend help me get the string on - could not quite do that myself. I can span it my myself with no trouble, however. Am in the process of shortening the tiller a couple of inches - it's a little too long. Mike

11 or 8.5 inches of draw... it depends on how you measure draw.  I think they're figuring on @ 3 inches of brace height, with an 8 inch power stroke.  That puts the belly of your prod 3 plus 8, equals 11.  If you're working with 3-4 inches of brace and 7-8 inches of power stroke from string at rest to the lock, you're in the ball-park.  Geezer.

Guy at Alchem told me the last batch of strings they bought were "just a bit long" - that's what is causing the low brace height. how can they sell strings that don't correctly fit the bow they are sold with/for? Haven't heard back from them about that yet.

I can't speak for Alchem's string-maker, but in my shop, we make several different string-lengths and its also possible to get the pegs in the jig in the wrong hole... it's not completely obvious if a string is a quarter to half an inch too long, particularly if you've got new people in the shop, or an inexperienced shipping person boxing stuff up.  So yeah, it really is possible to get one or a bunch of strings that are slightly too long or short.  If the string is just a Bit too long, you can twist it a few turns to shorten it, but twisting can shorten the life expectancy of the string.  So yeah, it's probably an honest mistake... honestly, there's no percentage in sending the wrong thing... yet it happens now and again. 
Geezer.

This sort of thing happens to me fairly often, actually - just this week I ordered a set of safety glasses (clear) and received tinted ones - now, i'll get the clear ones free as that vendor is making good on his company's mistake, but that's just an illustration of what seems to be occurring more often. If I were a vendor, I would think twice before sending out mis-matched or incorrect items - or at least say something in advance to the customer. I only made this crossbow on a lark, thought it would be fun to have around. oh, well...just another page in the book.