Drop-in roller nut and reinforcements?

I read somewhere about roller nuts and their reinforcements sometimes being directly dropped into a mortise cut out of the top of the tiller. I notice on most of the work of Geezer and Lightly they drill the recess for the roller nut directly from the side then fill in the resulting hole with a plug of wood or antler and then often cover that with a lock plate or other decoration. The bows I'm wishing to duplicate have shallow inlays running along the sides of the tiller just below the table - to shallow to cover where a socket hole was filled back in. Also, these bows don't have decorative lock plates of any type. So, I'm thinking those particular bows must have had the roller nut recess done from the top or had some sort of socket constructed and then dropped in and glued in place. I'm envisioning something that would have an antler block fore and aft of the actual socket and then some bit of hardwood on the bottom to accommodate the lower curve of the socket. The whole thing would be drilled out with the forstner bit to the proper diameter, other recesses for triggers, springs, and the like cut and drilled in the tiller then the lock assembly with nut is dropped into the mortised hole and bone overlays on the table cover everything up. Thoughts, suggestions? One advantage I see to doing it this way might be that with the larger hole cut for the roller nut assembly, it might be easier to drill the hole for the tickler and associated hardware. I had a problem with drilling the channel for the tickler on my first bow and ended up boogering up the table badly enough that I need to put my faux ivory overlay on to cover the mistake.

Hi kiltedcelt,

I think the stock design of the crossbows you chose simply has enough wood in the area thus allowing for such a box to be chiseled out. I guess when done this way the sides are not compromised and therefore it only adds to the structural strength of the stock.

Also an interesting question...Was all this hardware dropped in from the top of the stock or the bottom? In my head I can picture doing it successfully both ways, but which is the most structurally correct?

PS: Kiltedcelt, are you making a "tickler" version or the "folding trigger" version?

Ivo,

I'm just going to stick with the tickler version. The more complex trigger mechanisms seen on the later bows look to be far too advanced for me at this time. I'll have my hands full doing all the decorative touches without worrying about how to construct a new type of trigger mechanism for which I have no prior experience. Anyway, I think the upper bow - the one with the geometric pattern carved on the sides is probably fired by means of the simple tickler mechanism. The lower, more elaborate bow may be fired by the more complex trigger that you're thinking of, but I can't tell just looking at that one poor quality photo. Actually now that you mention it, there isn't even a tickler visible in that picture.

Geezer here on mortised 'drop-in' locks. Many medieval crossbows used pre-constructed locks, dropped into a square mortise in the top of the stock rather than cutting a socket into the side of the stock. Bows constructed that way are much stronger through the lock than those that have the socket cut through one side
Mortised locks are very common on the fat Germanic bows, but in fact, the original Padre Island bow uses a mortised lock, as do many others. My apprentice Lightly and I make such locks on demand, but since they're more labor-intensive, we charge extra for them. So how do we do it?
Simply take a chunk of hardwood, about 6 inches long 3 inches high and as thick as the roller-nut is wide. Period roller-nuts run anywhere from one to two-inches wide, but the average is generally about an inch and an eighth to an inch and a quarter. We cut a pair of bone or horn blocks about half an inch thick, an inch high and as wide as the roller and glue them into a piece of hardwood a hair over one inch apart (for a 1 & 3/8 inch dia. lock). When the glue is dry, we cut a socket between the blocks with a forstner bitt. Now we've got a chunk of wood with a horn-reinforced nut-socket cut into it. While the block is still large and strong, we cut a trigger-passage into the bottom and one end of the block. Then we cut the block off flush with the ends of the bone-reinforces (lagers) Once all the passages are done, cut the made-socket to size and then mortise a square hole the same size into the top of the crossbow stock. Once it's cut to size, the prepared lock will be fragile, so go easy. Go ahead and cut the trigger passage in the stock so that it will mate up with the trigger-passage in the lock-block.
Fitting the block into the square socket is a bit of a booger. Your first mortise will take a bit of fiddling and cursing, but don't give up. If you get the hole too big, you can make some spacers out of thin bits of bone or rawhide. Eventually you'll get the two pieces to meet. Slather glue into the hole and slide the bits together, clamp and wait till it dries.
You'll find out why we charge more money for a mortised lock. If you want to do lots of mortises, you may want to invest in a mortising attachment for your drill-press or do as I did and get a dedicated mortising machine. It really speeds up the trigger passages as well as lock mortises.
Hmmm, perhaps I should convince Lightly to do a photo-article on mortising locks. That might help.
Anyhow, I hope the above helps. Geezer.

Geezer,

Thanks for the good description on how you construct those mortised locks. It sounds like a bit more work in some respects but if I'm envisioning everything correctly it seems like it might make constructing the tickler passage easier. I had a fair bit of trouble getting that right on my first bow. I second the idea of having Lightly do a photo blog on the construction of one of these mortised locks - it would sure help me out.

Kiltedcelt,

This is for you! This is our take on the Spanish bow, what David has named the "Padre Island Bow", as we make it as close as possible to the bows found in the spanish shipwreck off of Padre Island, Texas. David was able to handle the bits from the wreck, and take many measurements and make drawings.

We do need to make the metal cheek piece in two pieces and not one, (as they made it then) as thus far, it is too time consuming. This summer I hope to work with a local smith, and make a form that may enable us to make the cheek piece in one piece.

In any case, the photos start where I am making the block that will drop into the stock. Enjoy, and be sure to ask Geezer any questions. Altho, we are both going to Gulf Wars to sell bows, so it may be a week or so till you get answered...

Best!

Lightly

PS;

I see that THIS set of photos:
http://www.flickr.com/photos/swifthoundbows/sets/72157613494516821/
Is actually a much better example of doing that mortising...

Geezer here, to comment on trigger-passages. Most earlier bows... say 15th century or earlier had very long trigger passages. Essentially they cut one great long slot into the bottom of the stock and simply slipped the trigger into it. If you feel obliged to cover some of that slot later, just inlet a filler-block. So if you're having trouble doing short, 'pocket' trigger passages, simply drill a bunch of 3/8 inch holes in a straight line along the bottom of the stock and connect them with a sharp chisel. Lightly and I use a mortising machine and have a lot of practice, so we can make the shorter trigger slots, but in fact, we do almost all of the Padre Island bows with long, continuous trigger slots.
As Lightly said, we'll be outa pocket for the next week at a medieval fair, selling our wares. Don't have too much fun without us. Geezer.

Great stuff, so it looks like these triggers were inleted both from the top and the bottom..."top" for the reinforced roller nut seat and the bottom for the actual trigger assembly?