I have WOOD!

Hi Arbalist Guild members! It's been a while. I have been moving a bit and now am in Redding California. I have a great shop, stocked it with the tools I will need and yesterday, finally, I got my wood.

I have some cocobolo, indian rosewood and some maple burl as well as some ebony for little parts. I am drawing and getting ready to make some initial length cuts.

My last bow was tons of fun to shoot but the shuttle table was only made to accept two fletch. I have since modified it to take three fletch and can now just buy 21" bolts off the shelf and go shooting. It's much more accurate since I have reworked the string catch and completely remade the bow from osage and hickory. I am getting groups of about 8" 100 feet but I am going to order a chrony soon so I can start actually testing the muzzle velocity of my bows.

Anyway, just thought I would drop in since I am back in the swing of bowmaking and get reacquainted with y'all. Here's a shot of the bocote slide action bow with my new woods. I have decided to make my new bows slide cocking as well but with an upside down roller nut trigger. I have my metals and a friend with a plasma cutter ready to go. Getting really excited.

A view of the rail profile.

Hey welcome back And glad to hear things are getting settled. (I hope)
Grr work won't let me view your pictures so I can't comment on them yet. But having a friend with a plasma cutter is always handy.

very nice, looks like you have another thin lamination in that prod. Yes? Maybe you can tell/show us how you mounted the prod. And a very clever way to utilize 3 fletch bolts!

Todd

Thanks for checking it out guys! I mounted the prod originally with a really annoying tie of hemp twine but I changed it to incorporate a plug with 2 1/4" threaded shafts terminating in either end with nuts. On the inside the nut is inset and tightly glued to a piece of hickory and the "bushing" is an old Levi's jeans patch. The bow has a red oak cap "washer" and an osage bolt cover. I will take some shots of how it goes together.

My next bows will be a split limb design and have a standard cockfletch rail. I like this bow but I need to find a way to serve the string that won't wear so fast over the shapely rail.

Also, wood question: do you think maple burl will be strong enough for the limb riser?

Any wood would be strong enough IF you use enough wood. Maple is fairly strong and as you probably know so are hickory and osage. Really a lot depends on how it is designed.

Todd

Thanks, I figured as much. I guess what I am wondering more specifically, is: is burl more or less stress resistant in small pieces like that? I mean, I could design the riser in straight grain maple and know what I was getting by the grain. With burl it's harder for me to figure the tensile strength of the grain in the riser design.

I guess experiment is the solution. Hopefully I get it right before I waste too much material.

Hey Jake is back.

I've read that Burl is strong and solid, but it's not as durable as nice close grained wood...in other words it has no flexibility and chips/cracks, but again that depends on the design and the load you put on it. Try to avoid sharp corners and edges as much as possible as those tend to develop cracks(inside corners) and chip(sharp edges)

Good luck,

Ivo

Hey Ivo! Yeah, that's what I guessed looking at the grain. Maybe I will find a way to back the pieces or make them more or less decorative over steel or something.

I haven't made any all wood risers, but I've seen some. Some all wood ones and some with metal plates on top and bottom and large brass inserts for the limb bolts.

However, I think you can still calculate your way around this and do a really nice all wood riser. There is a chapter in one of Bowyers bibles that talks about measuring the strength of wood...they made some test pieces in form of square pegs, put them in a square hole and used a wooden lever (also with a square hole) and a spring scale on the end to measure how much force it takes to break the peg...from that point it's all hazy...I'll look for the books tonight and will scan the pages in the morning.

Ivo

Cool, thanks a lot man!

Todd the archer wrote:very nice, looks like you have another thin lamination in that prod. Yes?

Oops, missed that one. You are right, there is a layer of fiberglass in there.

'Wood Handbook' has the most complete reference on properties of wood I know of. It might have the information you want about maple burls.
For the rest of us the properties of woods we might consider for stocks, nuts or prods might save us time money or our health.
It is published by USDA Forest Products Laboratory. About $35 if you have to have your own.

I am super pissed right about now. I just got the first stock roughed out (cocobolo) and found a huge, nasty knot right in the weakest spot between body and butt. I am binning it and starting again on the second half of the cocobolo.

Grrrrr That is maddening. At least you have some more material to work with. hopefully you can figure out something to do with the first part.

Would a fiberglass laminate around the area work or wrap string and epoxy around the area to strength it up do something? Ok maybe not what you where first thinking about but still maybe later?

Basilisk120 wrote:Grrrrr That is maddening. At least you have some more material to work with. hopefully you can figure out something to do with the first part.

Would a fiberglass laminate around the area work or wrap string and epoxy around the area to strength it up do something? Ok maybe not what you where first thinking about but still maybe later?

Yeah, I will probably do something like that, a bolt inside the handle with epoxy holding it together.

Good news is, I am well on my way into the next piece and I have all the steps down pat so I should have the body and shuttle done by Monday if I kick butt all weekend.

I want to post my trigger design here and see what you guys think but I have to model it first to avoid any serious embarrassments.

Speaking of serious embarrassments...I looked over Tbb books and found that what I thought was a wood strength test was actually a glue strength test.

Sorry about that, really wanted everything to turn out for the best and ended up with the usual.

There is, however, a wood strength test called a three point test, but it seems to require a slightly more specialized setup.



http://www.doitpoms.ac.uk/tlplib/wood/wood_strength.php

I'm not big on calculations, so maybe some of you engineering guys can shine some light on this.

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The subject of burl wood for use in load bearing components is fascinating since the burl grain is a mystery in it's own, so I'll definitely do more research on it...thanks for the turn on, I'll chip in on the findings when something comes up.

Good luck,

Ivo

PS: So you are building a new bow or just doing improvements on this one?...or both? "I got Wood" is a bit vague.

This is a new bow. Rifle style with split limbs and an upside down roller nut on the shuttle/slide.

Body two looks great, no defects to speak of.

So, two weeks in and many failures later....

I have the stock/tiller, slide, cock fletch quiver and a couple sets of limbs made. I am working up many many models of the trigger assembly before I start cutting on the tiller and shuttle. The limbs pictured are osage and hickory but I have a pair of osage and fiberglass ones ready for...well, problems. So far getting things straight has been challenging but rewarding. I am still trying to figure out how to get the limbs aligned perfectly in the riser.

When finished it will have a nice set of adjustable sights (wood), front and rear, a tripod acceptor, a small cheek rest and a maybe cubby in the stock to store broadheads beneath a burl swing plate. So far the whole thing weighs about 8 lbs. I am hoping to reduce some of that in wood but add in some metal so hopefully it stays around there. I just weighed my first version slidebow and I was surprised to find it weighs only 6.25 lbs!

Anyhow, here's a couple shots of the work so far for anyone interested. Cocobolo and maple burl.

Wow, That looks good.

Hopefully it shoots as well as it looks.

I will make it shoot well. No matter what.

I have my original bow sighted in and I would get some video of me shooting but....(and this is horrible) the last time I was shooting, I got poison oak all over my legs while retreiving my target from where I stash it in the bushes. I was wearing shorts ans sandals in a shrub of the stuff to my waist. I have been in hell for the last week and a half.