German style crossbow finished

Hi, all. The crossbow is nearly finished, minus some adjustments and refinements. Overall, I learned a great deal on this project, and am ready to begin my next project, a Swiss bow.



Overall, I am pleased with this bow. I ended up getting a 100 lb. prod from Alchem, and am pleased with the power it produces. When testing yesterday on my club’s indoor range, I was getting an average of 4” of penetration using 3/8” oak bolts with 125 grain heads and two fletching (lots of refinements in the bolt making area is ahead of me) on a traditional round hay archery target. I shot mostly from the bench with sandbags, but did some freehand shooting at 12 and 25 yards, and for having never shot a crossbow, let alone one I built, I think I was getting okay groupings. The photos showing shot groupings are a 12 yards and then 25 yards, on a standard FITA target. I was averaging 4” of penetration at both ranges.



I have to do major work on the roller nut socket (or be more careful is more like it, as this one I am not all that pleased with, so the nut is a bit loose (not much, but enough, details can be provided). When I first shot this bow, I had made the string too low on brace, so it shattered my bone quarrel rest and tore up a bit of the table facing when the rest was struck (dovetailed in, you know). I made a shorter string bracing at almost 4”, and it performed fine this time.



I have no idea how fast this bow is, as I don’t own a chronograph. Maybe I can borrow one later, though. Certainly faster than a typical self bow.



I did a tiny bit of distance shooting, and got the bolts maybe 120 yards (more accurate distance testing is in the planning stage).



So, I consider this a success. I have always considered this weapon a testing ground to learn new processes and techniques, and expected to make mistakes and do re-dos. In that respect, I feel 100% satisfied.



Thanks for reading,



Dane

I have to say you did an excellent job. Beautiful design and really good finish. Thank you for sharing it.

Nice job. Couple of questions. I see no bolt clip (Not saying you have to have one) and noticed that on the butt end of the bolts you made that they are quite narrow and have a lot of taper. Are they made to wedge into the nut? Seems that this would make them more prone to splitting.



Anyway it really is a good looking crossbow you have made and look forward to seeing your future projects.



Todd

Thank you, Old Wood. Your words are much appreciated.

Todd, thank you as well. When I said adjustments, that includes the bolt clip. I was so excited to get it to the range, I decided to hold off, but will fashion one soon enough.

Regarding the bolts, I am going to try different styles and see what works and doesnt work. The taper is indeed to fit into the slot in the rolling nut. Since this was my first rolling nut, I didn't have any experience to determine how big a slot to make in it in the first place. And since I can remove the quallel rest, I can experiment with various shaft dimensions and see what works best for this bow. Even if they are narrow at the butt end, they seem to be holding up fine. Given time, they may split or become ragged. Oak is the type of wood I used for this first set.

That looks great, like the brass detail bits.

Also looks like it shoots well. Nice work for you first crossbow.

Todd the archer wrote:Nice job. Couple of questions. I see no bolt clip (Not saying you have to have one) and noticed that on the butt end of the bolts you made that they are quite narrow and have a lot of taper. Are they made to wedge into the nut? Seems that this would make them more prone to splitting.
Todd

Wedging the bolts into the fingers of the nut is a very period feature. And unless you are using piano wire for a string, there's no way your are going to split a hardwood bolt at the butt.

Basilisk, thank you. It shoots far better than I had hoped for for a first bow. I hope to put up some shooting videos, but am not sure how to post those yet.

Darivs, thanks also. And thank you for your kickass buildalong. That is the reason I was able to build this bow in the first place. Quick question on the strings...how much stretch can I expect out of a sinew skein? I used your guide...25 strands of artificial sinew, etc. I was thinking about using fast flight for my next string, and wonder if total non stretchiness is a good or bad thing.

stoneagebowyer wrote: Quick question on the strings...how much stretch can I expect out of a sinew skein? I used your guide...25 strands of artificial sinew, etc. I was thinking about using fast flight for my next string, and wonder if total non stretchiness is a good or bad thing.

I used artificial sinew mostly because that was what I had one hand, and didn't know where to get quality hemp like that used in original skeins. One of the tricks I learned was to prestretch the sinew, in length of 30' at a time, then wrap the loops around a board with nails in it to start making the string. Then I form the end loops in the same knot style as shown in Egon Harmuth's DIE ARMBRÜST. Using steel rods, even screwdrivers, the eyes are stretched apart to set the eye knots and even out the tension in the strands. Now for the cool trick. before you start to serve the eyes, put the unfinished string in the microwave oven on high setting and heat it until the wax begins melting, the using the steel rods, stretch the string as tight as you can. The water content in the string is what causes it to heat up. Excess wax that oozes out is smoothed back over the string. Stretching it hot will really even out the tensions in all the fibers, even in the eyes. This is so there are no high stresses in only a few fibers such that they may tear. Overall, the skein will stretch in length about one inch or so, depending on how many turns or strands (how thick) you made the skein. When you are satisfied that the skein is set, and will stretch no further, then you proceed to serve the eyes and center portion using coxcombing with your favorite fray-resistant cord. I use plain old brown waxed linen. Some people use Dacron, which is much stronger, but I stick with natural materials and live with the drawbacks of the old traditional materials.

You want the string to be as non-stretch as possible. You don't want the string to be stretchy like a rubber band or you lose power. It's the prod that does the work. Of course, if you have an extremely string prod and you use hemp (the most non-stretch natural fiber) and the string is too thin in diameter, it will eventually break with a snap at one of the eyes. The eyes are the weakest point in the string because the skein fibers are bent around a small radius at the nocks of the prod which adds more stress to the strands in the outermost diameter away from the nocks. Since the stress is not even, these fibers may exceed their tensile strength if the string is too thin, and there are not enough fibers in the skein to share the load. If the skein is thick and strong enough for the prod, it should withstand the force of snapping taut when firing the crossbow. You will note that since hemp is strong but non-stretchy, the skeins on heavy medieval bows are rather thick, sometimes 1/2" in diameter. I imagine that the size may also be due partially to poor quality of the hemp strands themselves, but this is just speculation. The huge bars of steel that I have seen on heavy sporting crossbows certainly merit a thick, heavy skein. For the light crossbows we typically make today, a thinner skein is desirable because it is faster (less weight and table friction) and thus results in more velocity of the bolt, as Iolo (Geezer here) will attest to from his experience. You want the skein to be as thin as the materials will allow it to be without reducing its lifespan.

You will note that on heavy German sporting bows, the spanning distance (draw) is as low as 6". The effect is that the bolt is practically slapped into flight. It would be interesting to study why the Medieval bowmakers had such short draw lengths combined with thick and heavy steel prods versus longer draw lengths with lighter prods. Perhaps the heavy prods were too stiff to allow a long draw length. No wonder they often needed the crannequin!

Thanks for the directions! I followed your advice carefully from your web-based instuctions, and went to the trouble of creating a Word doc and pasting in each photo so I had your buildalong in a binder in printed form for easy reference.

I will have to try Fast Flight and see how that performs (that material is becoming more and more popular with self bow makers vs. D-50 Dacron, including the heavy war bow makers). Probably increase the number of strands if necessary to get a larger diameter skein, and maybe use modern bow serving material as I did for the center serving on the eyes as well. I had used waxed linen thread the last time for the eyes.

I think that strings can be a special area of study everyone can benefit from.

At just 100 lbs, I can still feel my wrists complaining from the process of drawing the bow.

Love the look of that bow,you did a fine job there,keep up the good work.

Beautiful bow! It looks like cherrywood? And, micarta top? have you any closeup photos?
And Darivus, I found your post about the strings very interesting, thank you...

Best!
Lightly.

Fantastic work stoneagebowyer! I'm with the guys - closeups would be awesome. I see some neat details that give off a feeling that you took your time to get everything right...that, I like.

A video would be out of this world...I've been trying to get people to post videos, but it just seems not everyone is into that. Really hoping you get around to it, you tube would be a good place to start since the forum has an integrated feature specifically for posting you tube videos. Good luck on your future projects and don't hesitate to ask if you need some help figuring your way around the forum or any other place on the net(ex: Youtube ) for that matter.

Thanks for sharing your work with us.

Ivo

Phil, Thank you!

Lightly, coming from a professional arbalist builder, your comments mean a lot. The tiller wood is cherry, and the table is hollywood (or holly wood), which was terribly dear, meaning about 50 dollars for a small 30" long board, most of which was sacrificed to the thickness planer gods, since the small 9" bandsaw gods didn't smile on my resawing efforts. It has a wonderful quality to it, the grain is nearly invisible, and it looks a bit like old ivory or bone after I put the finish on it. According to my hardwood dealer, finding any holly that is such a consistently creamy white is rare, too.

Thanks, Ivo. I did take some time - about 9 months from start to its current state. There were a number of do-overs, including the tiller, and the inlay decorations Darivs recommended in his build-along didn't work out at all well, so I ended up planing out the inlay work and used brass tacks from a flintlock trade gun project for the brass decorations. Necessity being the mother of invention, eh?

I will try my best to get some close ups posted today or tomorrow, and videos too. I will go the YouTube route, thanks Ivo. I am flying out to L.A. for a family visit in a couple of days, so if I can't get them posted now, then after I get back.

Dane

PS Any advice on posting vids to and uploading from YouTube? Hint taken! Thanks.

This site has to be my favourite,it is like a family affair thing all helping each other and this make's it all much more fun.Everyone has their own unique way of building their crossbow's,i just want to get out there and do lot's of crossbow shooting and video's as i love watching good interesting vid's and i have got one done and on the way which i tried uploading for the last 4 hour's and it did not upload i think due to being busy.Anyway it came out pretty good i think and ideally i need to get out and do long range with all type's of crossbow ammunition i particularly love shooting the fletchless micro bolt/bullet as these are cheap to make and no need to worry about breaking or losing them like expensive bolt's.I will try and upload this video to you tube tomorrow and the title is Mantis compound shooting bullet's,when on there i will post onto here to let you all know.

Let's see if this works.

Another video. Notice the fantastic production values



I will be uploading a few more videos and some closeup photos over the weekend, folks. Sorry for the delay.

Dane

Don't stop at a 100# Alchem prod. My favorite is his 200# plus prod! With a draw of 7-1/4", you'll be accused of bringing a gun to the archery range. Until my back got injured, I was routinely drawing one. Now I suppose I will have to put a pin in the stock and use the goats foot.

I'd love to go up in power, and have that prod in my workshop. The problem is #1, stringing the prod to serve the string, and #2, restringing it to complete the bow. Any suggestions about how you do it, Kurt?

Another video, set up near the target.

Nice vids...and by the looks of it the groups are getting better. Great Job.

The problem is #1, stringing the prod to serve the string

Old habits die hard, ey? I would serve everything on the jig even for a vertical bow.



Or was the procedure back in the day the same as with longbows - serving while the bow is strung? Hmmm...

#2, restringing it to complete the bow.

A bastard string would come in handy...#200 sounds like a blast of fun...and a even more of a blast to string...ouch.

Ivo

Thanks, Ivo. Cool too being able to post videos. Much more of that for me in the future, minus the ripped-off movie sound tracks. Carl Orff is way overdone for cheesy Youtube vids. I can, however, imagine the B-52s as a crossbow soundtrack. "Love Shack," perhaps.

Sometimes I am slow. Of course a jig would work fine for serving the center of the string. Particularly if you use non-stretchy string material like fast flight. Yes, on wooden hand bows, it is ideal to string them and then serve them, but these are not hand bows we are building.

I just love the term bastard string lol. The 100 lb. prod is a lot of work to string, and 200 - ugg. But I guess doable, or 200 lb. prods would not exist.

A bastard string is precisely what you need to fit the string to the prod. Geezer can show you how to make an easy fitting bastard string tool. I made a cheap device using some U-bolts that clamp onto the arms inboard of the nocks and some cable and even a turnbuckle to make adjust it even shorter. I know there are other, better ways. Medieval German bowmakers used a Spannbank (spanning bench) which drew the bastard string far enough to allow you to place the skein on the nocks. When making a skein, I usually serve the eyes in the same coxcombing covering as depicted in Egon Harmuth's Die Armbrüst, and serve the center of the skein after it is placed onto the prod.

I will have to ask Geezer about his method of making the bastard string, thank you! I replicated your varient for this one, the U bolts, a spanning wrench, steel wire, etc.

Any documentation for a spanning bench, or illustrations?

In any case, it is not the bastard string as much as the muscle power needed to yank back 200 lbs. that concerns me. With the 190# - 200# prod, I couldn't quite get it back far enough to slip the string loops over the nocks.

Off now to show off my new bow to some friends at the New England Atlatl Day, in CT along the Long Island Sound. The atlatl is another passion of mine.

Dane

There are some pictures of spanning boxes on the Swedish Crossbow forum. I am struggling with the translation features in Google, maybe someone else can find them. As I recall, it was a box resembling a long miter box with a wippe permanently attached and slots to hold the prod.

You give birth to a really nice looking crossbow. I like that type of style. Did you ever view the june 2-5 2011 event called(crossbow meeting Heidenau Germany".) It's somewhere on this wed site. Good luck in any&all future builds. Mike

Thanks for your kind words, Michael. It was a fun first project, I learned a lot, and made mistakes too. My next one that is currently in-progress I think will be a better weapon.