Primitive Archer

Main Discussion Area => Bows => Topic started by: PlanB on November 22, 2021, 10:52:28 pm

Title: Hemlock Branch Bow
Post by: PlanB on November 22, 2021, 10:52:28 pm
A couple weeks ago I was cutting a dead ash for firewood in the woods in back of my house, and there was a hemlock in the way of the fall I needed the ash to take. Otherwise it was going to hang up, so I decided to fell the hemlock first and cut it up for spring shoulder season fires. It had some nice looking branches, so I decided to take a couple of those and try a bow out of them.

Tonight I started to peel one. The bark on hemlock branches is very scaly and rough. There's basically three layers, the outer scales, then a stringy layer, and then a crusty spongy layer. I took the scaly layer off first with a dull pocketknife. It was kind of fun, relaxing not thinking about anything else.

Title: Re: Hemlock Branch Bow
Post by: PlanB on November 22, 2021, 10:56:02 pm
Next I started on the other two layers -- I spent a couple hours on this because that got me down to the sapwood layer, which I wanted to keep. I marked the upper and lower surfaces of the branch. The top will be the bow back.

 
Title: Re: Hemlock Branch Bow
Post by: bownarra on November 23, 2021, 02:26:08 am
Interesting but hemlock isn't really bow wood? It will be interesting to see what you make.
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 23, 2021, 01:37:41 pm
No, not a bow wood.

Bark all peeled. Ends will be painted with melted paraffin wax. The branch curves in the wrong direction, sideways to the top and bottom.

Title: Re: Hemlock Branch Bow
Post by: PlanB on November 23, 2021, 02:02:27 pm
This is an old branch. About 50 rings. Butt and tip both show reaction wood toward bottom. Tip has off center heart.
Title: Re: Hemlock Branch Bow
Post by: PatM on November 23, 2021, 05:52:09 pm
I would bet it would make a good two wood style bow as used in North Eurasia.
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 23, 2021, 08:59:29 pm
I've thought about that a lot. I have black, yellow and white birch, all three, growing right in amongst the hemlocks, so backing with a birch is almost a natural combo. But I'm going to hold off on that and see what I can do with the hemlock by itself first.

I'm thinking a relatively long bow with deflexed tips and a trapped or rounded belly. Basic and modest.

This is eastern hemlock, btw. Canadensis.

The hard part is going to be the side bend. There are better branches in the world.

Title: Re: Hemlock Branch Bow
Post by: PatM on November 23, 2021, 09:40:27 pm
I would maybe get a few pieces for a bend test first, just to see how it behaves.
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 23, 2021, 10:19:25 pm
Hard to say without a dry sample. But I built my house 20 years ago with about half the framing hemlock, which I milled myself. Hemlock is very high in compressive strength, less so in tensile. Therefore dry sticks tend to snap apart when bent past yield. It gets very hard when dry and it can bend nails.

The branch wood will probably exaggerate the difference between compressive and tensile strength. I guess I could rapid dry a sample cut from a branch and try it. But I bet it acts similar to the above.

So, long bow, modest draw weight, and trapping or rounding the belly is my guess for survival (of the bow when drawn). Or maybe it's just firewood.
Title: Re: Hemlock Branch Bow
Post by: simk on November 24, 2021, 08:37:38 am
I dont think you will make a selfbow fom these branches. If...then you need bigger diameter. I haven't tried that but its weak in tesnion - I have seen oone from a branch with a rawhide backing once. Two wood bow is the best way - the lower side (compression side) makes a very good belly. But this for sure is not the easiest way to get a first bow. good luck.
look here for an example:
https://www.primitivearcher.com/smf/index.php/topic,68758.0.html (https://www.primitivearcher.com/smf/index.php/topic,68758.0.html)
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 24, 2021, 11:28:27 am
Beautiful bow, simk. I admire that one a lot.
btw, this isn't a first bow. But I admit there's a good chance it won't work out. I'm just interested to try.
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 24, 2021, 12:46:15 pm
Some specs........present branch weight is 1134 grams, length is 71".  Diameter at butt end is 1.5" and at tip 1". A good bow for my draw would be 40 lbs on 27".
Title: Re: Hemlock Branch Bow
Post by: simk on November 24, 2021, 01:08:10 pm
only from top notch bowwood (for example dogwood) you will get a bow at these specs from a thin branch like that. one of the main problems you are confronted with small diameter pieces  is the extremly high crown concentrating massive tension in one spot. If...then only a very good bowwod can do that. but you anyways gonna try,....sometimes some things just gotta be  (-S 
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 24, 2021, 01:27:16 pm
Lashed down.
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 25, 2021, 08:52:23 pm
After a day indoors, 1063 grams. Original curve 6", now 4-3/4".  Re-lashed tighter.
Happy Thanksgiving.
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 26, 2021, 04:23:23 pm
Day 3:
1043 grams. Curve 3-3/4"

Day4:
1025 grams. Curve 3-1/4"

Day 5:
1014 grams. Curve 3-3/4" (measured with springback after 20 min.)
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 28, 2021, 03:30:53 pm
Today I drew a center line down the back, following the grain, and then marked out widths to trim the butt end down to almost the same width as the branch end. I also trimmed some of the belly off at the thick end. Then I weighed it before lashing it back down. Weight is presently 912 grams, which means I trimmed off 102 grams of wood. The heartwood is quite hard, and the sureform rasp tended to skid over it. A sharp low angle block plane worked better for me.
Title: Re: Hemlock Branch Bow
Post by: Fox on November 28, 2021, 06:27:20 pm
 (-P
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 29, 2021, 09:30:44 am
Thanks Fox.

Day 6:
904 grams. Curve 4-1/4"

Curve increased possibly because of wood removal altering the drying rate of part of the limb. But the curve is now in line with how I would string the bow to keep the handle in line with the tips, instead of sideways, which is a gain. I doubt lashing down will reduce the deflex further at this point, but I'll continue to dry it that way.

Change in weight due to drying, in grams has been:

Day 2, 71
Day 3, 20
Day 4, 18
Day 5, 11
Day 6, 8
Title: Re: Hemlock Branch Bow
Post by: PlanB on November 29, 2021, 12:37:19 pm
I took another 100 grams off the heavy end, bringing the limb to 804 grams before putting it away for the day.
Title: Re: Hemlock Branch Bow
Post by: willie on November 30, 2021, 03:10:42 pm

Curve increased possibly because of wood removal altering the drying rate of part of the limb.


I have found that the reddish compression wood takes longer to dry than the whiter wood, and it will also shrink longitudinally as it dries, causing "reaction wood" type internal stress. 
as you tiller, if you remove more of one kind (and expose proportionately more of the other) the limbs will move.

Title: Re: Hemlock Branch Bow
Post by: PlanB on November 30, 2021, 08:00:26 pm
Hey, Willie.
I guess we'll find out what the problems are when we start tillering.
Day 7:
784 grams (drop of 10), Curve 4-1/4" (no change)

Even though the each limb curves out and in in opposite directions (S Curve) the tips and handle center are all in a line.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 01, 2021, 04:48:34 pm
Day 8:
786 grams (gain ?)
Later..... noticed a small check starting through the center of the belly near the butt end. I put the branch outside to slow the drying.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 02, 2021, 10:59:39 am
Day 9
799 grams.

The branch picked up 13 grams on the porch in damp weather, and the check at the bottom end closed up again.

I brought it back indoors. Indoor humidity today is 33%. That's pretty low.  I'm putting a coat of linseed oil on the whole bow, Let's see if that helps slow the drying rate.

I'll have to to think about that check. It was hairline and about 2 inches long between two very small pin knots on the belly side about 8 inches from the tip. Gone today. If it opens again so I can find it, I might try a superglue repair.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 03, 2021, 09:53:35 am
Yesterday I superglued the belly check and linseed oiled the whole bow. I weighed it in the evening afterward and it was at 787 grams. This morning I weighed it and it was at 788 grams and the filled crack is unchanged.

This crack is very fine, and it looks like it might be fairly shallow. It's near the end of the bow, which is presently 7/8" thick and may get worked off when tillering the belly down.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 03, 2021, 10:52:59 am
I did some more wood removal on the branch. That brought it to 752 grams. I'm bothered by a side bend in the butt limb. I was going to just orient the bow to let that be compensated by the upper limb giving an S-shaped bow with the handle centered. But it just bothers me. And I do wonder how it will affect the arrow flight. And it's going to make tillering hard. I think I'm going to try steaming the curve out. That's a big question mark here because I don't believe softwoods are as amenable to that. And hemlock branches are a further unknown. But well, that bend bothers me, and this is an experiment, so lets just try it and find out.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 03, 2021, 06:55:34 pm
I gave it 40 minutes of steam, and the curve actually straightened over the pot. It was probably a drying warp. I nevertheless strapped it down bending in the opposite direction to prevent it from returning, and to allow for spring back.
Title: Re: Hemlock Branch Bow
Post by: willie on December 04, 2021, 03:39:43 am
PB,
sideways bends are tolerable if tips and arrow pass line up where you want,  and the reddish wood is high in lignin, which makes it very amenable to heat bending

nice experiment.
Title: Re: Hemlock Branch Bow
Post by: bownarra on December 04, 2021, 05:35:13 am
Don't worry about sideways bends until the bow is braced. Only then do you know for sure how the bow will 'line up'. Even with the string outside of the handle it isn't really a big deal (it will still shoot just fine) and almost to be expected when trying to make bows from small saplings like this.
your small check will be long gone by the time it is a bow. To avoid this happening (or at least reduce the chances) rough out the thickness taper to a stout floor tiller. The tips needn't be anymore than 1/2" thick.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 05, 2021, 11:43:15 pm
No problems here fellas, I just didn't like the curve and wanted to see if steam would do anything on a hemlock branch, and it did. I've been gradually working it down over the last couple days. We're at 602 grams and ready to brace. There's a fair amount of deflex, but that's intentional, as mentioned early on. Brace height will have very little tension.

This couple of old videos from John J Riggs was what got me interested in my own attempt at a softwood branch bow, plus having a cut hemlock with waste limbs to dispose of. Plus nobody saying hemlock was a usable bow wood.

https://www.youtube.com/watch?v=Ga6LCxd8zk0
https://www.youtube.com/watch?v=C1F7cT7s3LM

His bow is a 48"  ttt and draws an arrow to the low 20's.
I'm at 71" ttt so far so I think I have a reasonable shot at 27" draw. Performance will be modest, but so what? The goal is to see what can be done, and how good you can make it anyway.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 06, 2021, 12:21:25 pm
Shot the bow already. I wasn't planning to I braced it and it looked pretty good, so I pulled it back a bit and it still looked good. Kept pulling it back further and further. Still looked good. Nocked an arrow just to get read on the length. Still looked good. Didn't feel strained. Did feel a lot like my other bows, which are 40# 27" generally. So what the heck, go outside even though it's raining, and you've probably got a green bow, the heck with set, its a darn hemlock branch. And, well it shot where I aimed it. What the heck!

I never even got it on a tiller tree. All I'd done is rough it out, feeling for the taper all along both limbs (which are totally different in character) and done some eyeball floor tillering. That's it. It wasn't like regulation bow building at all.

Is it perfect? I don't know. Is the tiller what it should be? I have no idea. I haven't even seen it drawn from afar. I still want to work on it some more, and get some actual measurements. But this IS a bow. It's not just a branch any more. The branch wanted to be a bow, because it sure as heck was the easiest and fastest bow I ever made to any particular spec. The only thing I did was complicate it unnecessarily by steaming out a curve (which has since returned). I didn't even think it was ready to be a bow yet. It just was.




Title: Re: Hemlock Branch Bow
Post by: RyanY on December 06, 2021, 01:11:04 pm
Glad it got to send an arrow. I was worried this had Christmas tree bow written all over it.  (lol)  Success!  :OK
Title: Re: Hemlock Branch Bow
Post by: WhistlingBadger on December 06, 2021, 02:30:04 pm
That is really cool.  Amazing what you can do when there's not much to loose.  I'd love to see a full draw pic if you get around to it.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 07, 2021, 10:37:17 am
Thanks Ryan, Whistling Badger. Here's just a couple of quick photos of the bow rough floor tillered, as mentioned. The upper has some kinks and reflex between branch knots. The lower curves outboard as well as in line.
Title: Re: Hemlock Branch Bow
Post by: RyanY on December 07, 2021, 10:39:17 am
Too cool.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 07, 2021, 10:43:00 am
PS  I'm standing in front of the downed hemlock it came from. Just a pile of green branches in the background.

Upper limb close-up:
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 07, 2021, 03:44:38 pm
Steaming a little setback into the handle:
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 09, 2021, 01:48:09 pm
I put a simple coarse string handle on it, a coat of linseed oil, and a knotted long string and shot 50 arrows through it this morning to get a feel for how it's handling now. Weight is dropping only about gram per day at present 559 grams.

 I was getting nice shooting consistency with the branch butt-end up, so I might adjust the handle position some. Otherwise it's a perfectly good bow. I see no problem so far with using E. hemlock branch wood for a selfbow, but time will tell. I'll update as I shoot more with it.

If I were to do it again, and I probably will, I'd look for an upward bending branch, and one that didn't have side bend. This one was neither, though it has produced usable bow anyway, but it was just a salvage branch from a downed tree. Hemlocks grow with upward bending limbs from about the middle of the tree on up, and downward bending limbs near the bottom. One possible factor in wood quality though is that the lower limbs will have more and tighter rings and be thicker than the newer higher limbs which are also getting more light.

If you imagine the snow loads on these lower limbs it's pretty impressive that they got through 50 northern winters (in the case of my bow) loaded with snow and ice at the end of a 12 foot lever. Hemlocks mainly carry needles and side branches only on the end of their long pole-like limbs, not distributed along their length, forking, like a spruce limbs.

That's a lot more bending stress than a 20 year old vertical sapling gets, and the wood is much different and is designed by nature to carry very different kinds of loads. Whether or not hemlock boards or staves would make good bows, I don't know. Maybe not. But a 1-1/2" inch thick hemlock branch with 50 rings is I believe a different material altogether.
Title: Re: Hemlock Branch Bow
Post by: willie on December 10, 2021, 04:57:50 am
looking nice!

do you have a way to measure poundage? like at 2/3 draw? it should pick up weight as it dries, and maybe too dry might be a problem.
If it is overbuilt enough, and shoots at a poundage you like, you can watch the poundage at 2/3 draw and thereby the MC, putting it someplace cooler/damper if needed.
Title: Re: Hemlock Branch Bow
Post by: SpringyWoodPassion on December 10, 2021, 09:01:29 am
PlanB! CONGRATS. I've been following your progress too and couldn't believe you put so much work into this unassuming branch that in the picture looked EVERYTHING but a future bow. I would not have bothered to go through all this with such a "twig" and this is what I would have missed.
What you've done is so inpiring, really. I'm pretty sure this is how the hunter/gatherer thousands of years ago would make some of their bows.
Excellent!
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 10, 2021, 10:12:41 am
Thanks SpringyWoodPassion, it really wasn't much work, and the steaming probably wasn't necessary if a better branch had been selected. I also would have wiped on linseed oil as soon as any wood removal was made to lessen the effect Willie pointed out earlier, that the branch will warp toward exposed heartwood. But again even with less than ideal wood selection and wood treatment, it has still made a good bow.

Willie, the bow lost 3 grams last night, so it's still drying. We'll keep reporting until it stops and seems fully dry. I do think the linseed oil has evened out the drying rate across the wood because the deflex isn't increasing. Also I shot two dozen more arrows out of it this morning, full draw, and there was no measurable set. Accuracy was really good (in my hands anyway). I'm really pleased with that.

I'm still looking for my darn bow scale, my beeswax, and my serving spool, all of which I squirreled away someplace unknown 5 years ago when I stopped building. I'll find them, as soon as I wade through a bunch of boxes. it's bugging me.

Meanwhile, in feel, the bow stacks, which is to be expected in a deflexed bow of this type, since braced string tension is low or even slack. On my bow I've set it up with a little braced tension, I can pluck it and get a bass note, but it's a low tone compared to my flipped tip regular bows. And the initial 1/4 draw has comparatively low string tension. So the 2/3 draw figure is going to be on a curve somewhere.

I'll just full draw it with the scale when I find it. I'm not physically worried about doing that. I have 75 arrows through it and continuing, the bow feels quite solid and isn't taking set. The stack isn't extreme, and it doesn't feel like I'm pulling to a limit.

My only worry is that when I do find that scale I'm going to learn that I'm weaker than I was 5 years ago, and what I think is forty pounds ain't!
Title: Re: Hemlock Branch Bow
Post by: gifford on December 10, 2021, 03:04:54 pm
kudos on seeing a branch and thinking - there's a bow in there. You stuck with it and got a good shooting bow. Again, well done.

Title: Re: Hemlock Branch Bow
Post by: PlanB on December 12, 2021, 11:41:53 am
Thanks Gifford.

Willie, 34 lbs @ 27" so far. So I'm 6 lbs short.

It's still drying 555 grams now, 4 grams in 3 days, a little less than 1% MC drop.
Title: Re: Hemlock Branch Bow
Post by: PaSteve on December 12, 2021, 01:21:16 pm
Interesting build. Thanks for sharing your process and results.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 14, 2021, 10:02:57 am
Thanks PASteve.

The bow is now down to 552 grams, and draw weight is 35 lbs.

While drying does help increase draw weight, I think it's close to dry now. On the negative side drying also increases deflex and brace height, both of which reduce draw weight at 27". If I could permanently reduce deflex, particularly in the branch's butt limb I'm confident the bow would hit the 40 pound draw weight goal. The butt limb had the most wood removal, and that made it more susceptible to uneven shrinkage of heartwood vs sapwood.

My thoughts on steaming a semi-dry hemlock branch bow are, it tends to relax over time, because it's essentially rehydrating a section, and that section dries again and over time warps back quite a lot of the gain. Steaming does have some lasting effect, but I think you lose more than 50% of what the original gain was.

I haven't tried dry heat on the bow, and I don't know what the effect on softwood, or branch softwood would be. I may try it just to see if it will help. I've done it successfully on hardwood bows of elm and black birch, and it also worked on the challenge wood cottonwood bow, just no idea how a hemlock branch will act. There is so much lignin in the the hemlock branch's belly wood, and that is so hard already I do wonder whether it's just going to add brittleness.

I do feel the bow is plenty strong enough right now, and has good flexibility, it doesn't feel marginal at 27" draw, I could probably draw it further without problems, but 27 is my draw length. I think the wood left in the bow easily has 40 pounds in it, but the deflex is too great to get there at 27" draw.

Title: Re: Hemlock Branch Bow
Post by: PlanB on December 15, 2021, 11:36:31 am
No change in physical weight today, or less than a gram, but the deflex in the butt limb and brace height has increased to the point where I want to try to reduce it.

I'm trying to decide whether to take one more shot at steam bending it, or whether I should now try dry heat. I think the bow is near equilibrium moisture content.

I don't have a lot of confidence in the permanence of any degree of steam bending this particular bow at this point, but I don't think one more try will harm it. On the other hand the physical changes from dry heat bending it, whether they turn out to be positive or negative, are going to be structurally permanent, and the bow could be ruined.

Well this is an experimental bow anyway and we just want to find out what happens with hemlock branch wood so I guess dry heat bending will at least provide some information no matter what the result.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 15, 2021, 02:38:32 pm
I dry heat bent the butt limb without any problem. It was easy and I just used a straight 2x4 on edge with a single rope lashing at the end as the caul without trying to over bend it to account for spring back. I didn't try to remove all the deflex or add flipped tips, etc. The intention was just to reduce the deflex and brace height some. It's still an attempt at a very primitive bow style, using a softwood branch, and a minimum of form manipulation.

The wood really responded easily to heat -- I could feel it relax as I heated the limb and pushed down on the bow handle. Eventually the handle contacted the form. I applied heat for the middle two thirds of the limb. The tip was up a little because the lashing wasn't absolutely tight. I simply heated the wood to a golden color, not brown as in regular heat treatment. But the limb did retain most of the straightening treatment after it cooled. I also heat treated a small section of the other limb.

My guess is heat treatments removed about 3" of deflex across the whole bow. In other words with a slack string brace, the brace height moved toward the handle 3". It now will require a fair amount more tension to spring the string onto the bow. The heat treatment also removed a lot of the side bend of the butt limb.

I weighted the bow immediately after heat treatment and it had lost 2 grams. I set it outdoors (40 deg. F) to rehydrate, and it gained 1 gram in about an hour. I'll weigh it again in another hour.

The check in the butt end (mentioned early on) is a little more apparent now, but it still looks quite fine and shallow, and I don't think it's going to affect the bow. It may close after rehydrating.

The questions now are, has the draw weight been increased? Is the straightening relatively permanent? Is the belly now more subject to chrysalling? Is the bow now weakened or made brittle?
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 16, 2021, 11:09:51 am
Made intended weight and draw.
Title: Re: Hemlock Branch Bow
Post by: PlanB on December 17, 2021, 10:17:41 am
Below are the present configuration, unbraced and braced.  I shot 100 arrows through it yesterday and today, it's quite accurate and I like shooting it as much as my favorite elm stave bow.

It's definitely and oddly asymetrical; the thicker shorter and more massive butt end is actually less stiff than the more delicate branch end, and I shoot with that shorter end up, and the handle well above the bow center. The upper limb also curls to the left. This bow is not going to win any contests for tiller or appearance, but, in fact as it stands now, the bowstring is perfectly center shot over the top of the handle, and arrows fly consistently without wiggle to the target, and even though the lower limb is longer it is stiffer, and everything feels right.

I'm certain with a better limb, or a more fastidious bowyer... or both, an eastern hemlock branch bow could be a thing of tillering beauty, but for me, I just like this bow as is. It is what it is -- a branch lopped off a downed tree that shoots an arrow well, and seems quite rugged. I really don't feel like it's close to overstressed, and I'm pretty sure more weight or draw length could be had out of this same bow. But I just have a feeling that this will be a long lasting bow that's easy to string, retains weight and shoots accurately. We'll see. Anyway yup, hemlock branch is a good bow wood, Self bow wood, it is, in fact.