Number Two

Here are a few images of my latest project. It's really a test bed for some ideas I wanted to try out. Wasn't sure if it would all come together into a shooter or not.

Some of the features I was wrestling with were a mechanical safety, a bull-pup trigger configuration with at least a bit of mechanical advantage, and fabricating everything myself except the prod and string. Those will be for the next project!





The prod is 150# fiberglass, covered with nearly completetly in leather. It's held in the socket by wooden wedges. It draws a full 12" from rest to the lock nut. The wood is Ash, not what I would reccomend for a pistol grip since it's so splitty, but it was cheap! I mitigated the splitting factor by drilling a 1/2" hole all the way through the grip and gluing in an oak dowel. The finish is a combination of ebony stain, black enamel paint, and polyeurethane. I was going for a faux antique look, and like the almost "camo" pattern I came up with. The lock plates, prod plates and trigger/lock bits are blued steel, the grip guard and stirrup are painted aluminum. The nut is delrin and the nut socket is UHMW plastic. More on that to come.



Initial survey indicates Yes! It's a shooter. The projectiles are 16" overall, 3/8" carbon fiber tube with Richard Head points, plastic fletching, and small screws glued into the butts.
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I still have a lot of work to do on it, though, and this is where I'll do it: The arbalist stand I just finished. The best part is the only thing I had to buy was the jack for $20, the lumber and metal tool stand I picked up for free.

Greetings,
Nice bow, the finish is quite unique.
Question about your arbalist stand. Have you tried it out yet? What keeps the bow or jack from kicking out when pressure is applied? I think I'm on the right track, a bow press, right? I like the simple design. Was needing something to press my bows also. I am using a double ratchet system that I seen in a post from Todd the archer. This looks much easier.

jds6

PS: What size dowels are used, and how are they mounted?

Oh babea!

Haha! Looks wicked, Gnome.

In my long lost build, (~behind the scenes~) I also sewed on some leather on the prod(left some material as I'm thinking about how to best sew the tips closed) and also got the stuff ready to stain the stock black. By the way, is that stain or the how the wood was from the start (seen some wood that's been sitting at the bottom of a lake with a similar marble texture to it)

Anyway, the bow looks...ahhhh - SWEET!!!

Quick question: Any problems with it?

I see some fletchings *stripped*?...does the string jump the arrow sometimes?

Also, maybe you can give us a closer look at the points you are using - it seems the arrow is sitting on the track with it's tip sticking up.

All in all, let us know how it shoots. If any problems, I think we can have them resolved in a jiffy.

Ivo

Thanks, Ivo. There are a few wrinkles I need to work out, and I plan to post more detailed photos. The track actually curves down toward the nose of the stock, since the bolts are so short I wanted to reduce friction there. The fletch missing from the bolt in the target wasn't stripped, it popped off when it struck because I was too impatient to allow the glue to set fully! The wood was nice and blonde and pretty before I got ahold of it.

Jds6, once the pressure from the jack was applied, the stock did not want to move in any direction but the way it came from. Like jacking up a car, you'd have to hit the jack or the stock pretty hard to get it to kick out. Of course I didn't take any chances, and put a couple of sturdy straps around the stock and the timber, just loose enough so that they could slide easily but not get too far apart. I plan to bolt the jack to the base of the stand. Also not shown is the thick leather pad I put between the jack and butt of the stock, this protected the finish on the stock but also helped lock those pieces in place once it was compressed.

The timbers are 4"x2.5" pine and the dowels are 1" oak, glued into holes drilled all the way through the timber and reinforced in back with plywood plates.

Ahhh, ok. I just had a problem once with the string jumping and stripping the damn fletch...anyway, glad to hear it's all good.

Definitely want to hear what stain you used. Give it up man.

Also, if you guys ever need to string/un-string the bow in the field, there's this *no jack* trick.(I even used it with my compound a few times *not recommended* - without cams helping, that's 250-300 pound limbs...so, just saying. )



Ivo

Nice video, Ivo. Thanks for posting it!

Dane

regarding the finish,I put a couple of heavy coats of ebony stain on and let it soak in good before rubbing it out. Then I started poly coats, buffing it down with steel wool between coats. I tinted a couple of coats of poly with the ebony stain, but I still wasn't getting the dark areas I wanted, so I painted the whole thing with flat black enamel. When that was dry I rubbed it out with steel wool again, only making sure not to rub too hard where I wanted it to stay black. Another coat of poly and I called it done. I don't think it's pretty, but I think it's interesting, and close enough to what I was going for.

That looks great. but wow sounds like the finish takes a bit of work.

Glad to see it shoots as well as it looks.

Ahhh...A "swinging stirrup" I like that!

The swinging stirrup was one of my key design points, I just thought it would be cool for it to also serve as a bipod. Another key point was the mechanical safety, which I think was a successful design but sloppy implementation, it's not set in the stock quite straight and binds a bit. Here's a detail shot of that, along with the bullet stop I made for it. I searched all over for a bullet stop but couldn't find one of an appropriate size, then realized what a simple device it was and sure enough I had everything I needed to make one- a scrap of brass tube and a ball bearing and spring that fit nicely into the brass tube. It's about the size of a .22 shortie and works perfectly. Cutting one end with a rotating tube cutter gave just enough constriction to hold the ball bearing, the other end I cut with a dremel but left a bit attached so I could flatten out a tail of brass and bend it over to hold the spring inside.

Here's my "swinging stirrup" on my crossbow before it was created by Geezer, The Master Bowmaker.

That's a beautiful piece, Olrono. Do you have any shots of it finished? Is the prod held by wedges?

This was a somewhat final design sketch for this piece. Hmm, seems like there's a fairly prominent element of the design missing from the work in progress. I found a good deal on a 4x32 5 step reticle scope a few months back and really wanted to mount it up, and that was the primary inspriation for starting this bow. I wasn't very confident I could pull off the scope mount, though, and at one point gave up and started planning iron sights for it. The scope kept calling, though, so this weekend I buckled down and I got it done:



I started with a section of 1.5"x2" aluminum rectangular tube with 1/8" thick walls. I was concerned it wouldn't be stable enough but it's really solid. The hardest part was tapping the screw holes for the weaver rail. Would have been a lot easier with a tap and die set! Luckily I had a few extra screws that gladly sacrificed themselves for the cause. I still need to fine tune the shape a bit, smooth out the finish and paint it. I plan on adding a cheek rest to the stock, probably a stacked slab of formed cowhide, plus a few other minor enhancements, then soon it's off to the range to get the scope dialed in.

Geezer here, with a comment about fitting scopes onto crossbows. Those of you who've actually tried a scope on a crossbow realize the big problem with a scope is the very low velocity of your bolts. Essentially scopes limit the amount of elevation you can get in your bow and still look through the scope.
Many years ago, I saw a crossbow by Dave Benedict (a highly regarded maker of modern-style crossbows) that mounted the scope on a graduated quadrant. The quadrant allowed the scope to be kept level when the stock was elevated for longer shots. Of course, that required the shooter to do some sighting-in, to establish range/elevation/with selected bolts, but it DID allow the shooter to put the target in the middle of the scoped sight-picture at any range. I thought it a pretty cool solution to a difficult problem. Maybe somebody oughta give it a try! Geezer.

Thanks Gnome, I have to say I like yours too! I like the "medeval" style best, but I have to say for a modern type yours is really a good design and the scope mount came out real good! The Geezer is right about that scope tho...since the projectile doesnt fly flat like a rifle, its hard to get it right on sighted in. But...having such a good bow I know you will have fun sighting it in. Yes my bow is held in with wedges, and I was thinking about taking some pics of it to post, there is one posted around this place somewhere...

Thanks for the input, Geezer. I guess I should clarify that I wasn't really going for long-range with the scope- just trying to compensate for my poor vision at medium range. Plus I'm no hunter, and don't like to have to walk too far to pluck my bolts out of a target. That graduated quadrant mount sounds interesting, though. Hmm...

Very cool crossbow Gnome. I like bullpups too.

Can you please show a diagram of how you made the trigger/safety. Also me and my brother spent a while figuring out how to make a solid drop forward rail ~ how did you do it? I get teh side plates made from angles, but is anything connecting them?

We had a similar idea, but decided to notch a square tube, bend it and weld it, so the rail is one piece and is riveted into the trigger housing. (i really need to take a picture for full effect, I know )

Antho

PS, I got the same scope on my crossbow (I think), it's the one with a cool little sun shade right?

We had a similar idea, but decided to notch a square tube, bend it and
weld it, so the rail is one piece and is riveted into the trigger
housing. (i really need to take a picture for full effect, I know )

It kinda goes like this...

Spoiler:

The scope mount was made from one solid piece of aluminum, cut from a 2x1.5" rectangular tube with 1/8" walls. Here it is just prior to painting, you can see I tacked a couple of small washers inside to fill a gap to make sure it goes on straight and true. It mounts using four of the existing holes that I made to secure the lock plates (two per side) plus two new holes.



Here's a clearer shot of the safety, it's pretty simple. Just a 1/2" steel rod machined down, with a small tension pin to limit it's rotation to 90 degrees, and the bullet stop to lock it positively at the full safe and full fire positions due to small indents ground into those spots on the safety.



Here's a couple of poor diagrams showing how it interfaces with the release mechanism first in the safe position:





Then the fire position where the release lever is allowed free movement:





And a photo of the safety in place with the lock plate off. That's what I mean by sloppy implementation, I sure wish that was prettier! Works, though.

Your crossbow stringing / bracing stand looks great. I am putting together a similar one, with a pneumatic car jack I picked up at Harbor Freight.

If you don’t mind my asking, and I am not sure I am wording this right, but what kind of tool stand is that, and can you find them easily? Does it give a steady hold for the crossbow as you jack it up to bend the prod arms against the two hardwood pegs? Does the stand need to be anchored to the floor at all? Since we rent, drilling into the shop area’s concrete slab floor is not a good idea. Same goes for anchoring the upright timber in the wall.

Overall, you have built a great-looking, cool crossbow anyone would be proud to own and shoot.

I do get excited by simplistic engineering. And your safety mechanism is just superb.
Keep up the great work.

Design more and your followers will come!

Peter..............

Thanks Peter, and Stoneage.

Regarding the tool stand, it once supported a pneumatic grommet press. I work in a sign shop, and this was one of the most worthless tools ever invented, and after collecting dust for a few years was relegated to the dumpster. Being the packrat that I am, I took the whole thing home and dismantled it. It yeilded lots of interesting parts, springs and whatnot, but the most obviously and imediately useful was the stand. I imagine it was custom fabricated for the grommet press, but it's really simple- big steel plate on the bottom, big steel square tube, and smaller steel plate on the top. I cut the timbers for the spanning crucifix to wedge between the two plates, locked in place by a couple of wood screws top and bottom. It's handled any load I've challenged it with so far. One of the handiest things is the wheels- I can tip it and roll it around the shop! that's good, because it's really quite heavy.

Thanks, Gnome. I was looking for tool stands, but they are just too small and too short for what you did, and I want to do.

Dane

Sweet.

I'm glad you captured the nut in the pic. I noticed that there was no axel hole for it in the sideplates and figured that you sunk the nut into the stock to a point where it could no longer pop out, but didn't expect a resin block retaining the nut. I'm assuming you went this route to help reduce the friction. Also nice move in making the little retention slots for the resin block to grip into the stock. I love these little details more than anything, so props to you...the little blemishes here and there are nothing compared to the path you're on and the overall coolness factor of this project.

Thank you for sharing this build with us.

Ivo