Primitive Archer
Main Discussion Area => Bows => Topic started by: txdm on December 29, 2017, 09:18:38 am
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I have abundant ERC boards but not enough hickory board left over to make a full-length bow.
I'm wondering if I could rip two ~1/4" backings of hickory, then glue them down to an ERC stave (one on each limb).
How does ERC hold up in compression with a hickory back?
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So after ripping you have a backing material 1/4" thick? Will you splice the two ripped backings at the handle? I think that sounds like a goid idea. Hickory is stiffer than ERC so you would want a thinner backing anyway, maybe 1/4" is still slightly too thick but I have no experiance in the matter, just theory. Erc is a good compressiom wood so it's good it's on the belly.
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If you can butt the backing strips at the handle you will be OK. You could always add an overlay over the joint for security if it worries you.
Hickory is a good backing for ERC but like gfugal said, 1/4" is a bit thick. 1/8" or less would be ideal.
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OK, I can rip to 1/8" and butt them together at the midpoint on a non-bendy handle.
My only experience so far is with all-hickory boards. I'm looking forward to this, but I dont know what to expect from the ERC. I'm sure it would be lighter, but will it handle compression better than all-hickory?
Here's my layout plan... hoping to get 50# @ 28", but I'd settle for 45#
(http://www.dmcknight.net/forumpics/erc-hickory.png)
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That should be a good design. If you find the limbs are getting to thin while you are tillering you can tiller from the sides to narrow the limbs some.
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You can do a small v splice or overlapping scarf joint of the two pieces and then an overlay and cord wrapped handle for full security.
Pope mentions the ERC hickory combo as a yew substitute in Hunting with The Bow and Arrow.
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You can do a small v splice or overlapping scarf joint of the two pieces and then an overlay and cord wrapped handle for full security.
I've got enough to do one of those too :)
Pope mentions the ERC hickory combo as a yew substitute in Hunting with The Bow and Arrow.
I'm surprised it's not more commonly done.
Do you have any recommendations on the better glue to use for the lam between TBII and Knox Gelatine? I dont have a planer machine.
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You will need both glue surfaces flat and smooth and well matched for both glues. I would suggest the TBII.
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OK, thanks. I'll use a fine cut table saw blade for the hickory lam, then sand both as smooth as possible.
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That should do it. I'd do a dry run first to be sure you get good mating.
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More questions:
Should I try to put in a few inches of Perry reflex during the glue-up, or is that getting greedy for my first try at a lam?
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I would glue in about 2 1/2", kind of pretiller the belly lam so it bends in a nice even arch instead of just coming up mid limb when you glue it up, it will make tillering a lot easier.
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I would glue in about 2 1/2", kind of pretiller the belly lam so it bends in a nice even arch instead of just coming up mid limb when you glue it up, it will make tillering a lot easier.
Not sure I follow what you mean... tiller the belly lam a little first before gluing it to the back?
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Yes, that is what Steve means.
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so it bends in a nice even arch instead of just coming up mid limb
I am following along and hoping that Steve can clarify what kind of arch txdm should be looking for? or what he is recommending to avoid
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I could cut an arched form for it.
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I got my backings cut...but... :-[
My table saw fence has a broken securing latch that allows the top of the fence to rock away from parallel to the blade, so it was a frightful and dodgy ordeal to get them done. The technique I used to was to feed it halfway through, lift it up carefully, then flip and feed the other half. I still have all my fingers, but a new Delta T30 fence and rails is on the way.
The backings currently are both 1/4". I watched some youtube vids and found some ways to do it safer using jigs next time when the new rail comes in. I'll take them down to 1/8" then plane and sand them flat by hand.
Overall I'm still really excited about this bow. I think the handle billet will be hickory as well.
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txdm, take the hickory backing strips down to 3/16". By the time you remove the tool marks you will be at 1/8" or slightly less.
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Sounds like a good plan, and the blade can nibble it all away without any outfeed.
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Today I got the new table saw rails/fence put on and shaved the laminates down without losing a finger!
After that I started working down the last 1/16" to get them to 1/8". I tried my hand with a stanley block plane and found my skill lacking. So light passes on the belt sander, then alternate scraping and hand sanding was the work of the day. They'll need another few passes before they're ready.
For the splice I'm planning to try for 30°.
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When I get something that thin I don't use my planes. I take a piece of belt sander paper and cut it staple one end to the grain end of a board then clamp the other end. Then I can place the work piece on it and slide it back and forth. This works faster than you think and if you pay attention you can get it dead flat or way flatter than by hand. I call it the poor boys belt sander. Its not nearly as risky as a belt sander at this point. You can make a couple push blocks one for each end with scrap 2 by 4s. Looking forward to see how she comes out. Good luck.
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A big ol sanding block... great idea!
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I take a piece of belt sander paper and cut it staple one end to the grain end of a board then clamp the other end. Then I can place the work piece on it and slide it back and forth. This works faster than you think and if you pay attention you can get it dead flat or way flatter than by hand. I call it the poor boys belt sander. Its not nearly as risky as a belt sander at this point.
I did this today to finish them out and it works great. You should put this in the Tips and Tricks thread.
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TXDM, I would but most folks don't want to hear how poor folks do it. LOL My favorite part of any craft or skill is to sit back and think how the hell did they do this before power tools. It always boils down to ingenuity, simplicity, sweat and SKILL. Ive watched a lot of ole timers I learned a thing or two about how to make do, I'm more than happy to pass it along.
I have access to ERC so I'm looking forward to see how this goes. Good luck and Good shooting.
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so it bends in a nice even arch instead of just coming up mid limb
I am following along and hoping that Steve can clarify what kind of arch txdm should be looking for? or what he is recommending to avoid
The reverse of a low brace profile.
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I found the most pristine and straight-grained cedar board I've ever seen in the leftovers from a gate project.
Hickory backings laid on the cedar board. Also pictured is the belt-sander-block.
(http://www.dmcknight.net/forumpics/hickory-erc/laminates1.jpg)
(http://www.dmcknight.net/forumpics/hickory-erc/laminates2.jpg)
Here's a closeup of the splice at the handle (in progress). I originally planned on 30°/60° but went with 45° to keep it simple.
(http://www.dmcknight.net/forumpics/hickory-erc/laminate-splice.jpg)
Obviously, there's more work to do there. They line up fine if you rest a finger on the corner that is lifting. I think this is an indication of a slight crowning on the glue side that still needs to be flattened. I plan to lay them side by side and work on them together with the scraper and light sanding. Time to get out the +1.5 reading glasses for this one.
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I was using a disc on the side of my belt sander to make the miters. The little table was slightly off, plus defelction of parts, so I kept refining it down to the last 64th.
(http://www.dmcknight.net/forumpics/hickory-erc/laminate-splice-2.jpg)
The center is now marked and the profile is drawn onto the backing strips. I think next step is to cut the limb profiles on the backing strips, then lay those on the cedar board as a template to trace and cut.
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One more pic, after scraping the miter's flatter.
(http://www.dmcknight.net/forumpics/hickory-erc/laminate-splice-3.jpg)
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You could leave the backing full width only cut the belly out? Which ever way you do it id leave plenty of room for error. as far as getting it all even after glue up with out having to go smaller because of a boo-boo. Pat B has a cool trick with wooden dowels during his glue ups tp prevent slipping.
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I take a piece of belt sander paper and cut it staple one end to the grain end of a board then clamp the other end. Then I can place the work piece on it and slide it back and forth. This works faster than you think and if you pay attention you can get it dead flat or way flatter than by hand. I call it the poor boys belt sander. Its not nearly as risky as a belt sander at this point.
I did this today to finish them out and it works great. You should put this in the Tips and Tricks thread.
That's just the kinda tips I'd like to see on that thread to JW
Can't wait to see this finished bow. I just love the look of red cedar heartwood.
Bjrogg
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After a brief hiatus due to weather and other projects, I finally got back on this one. This weekend I cut the profiles into the cedar and hickory using a table saw followed by refinement with a block plane.
I also trimmed the limbs of the cedar down to a little under 1/2" thickness using the table saw, then rounded the corners on the belly side.
(http://www.dmcknight.net/forumpics/hickory-erc/rough-in-1.jpg)
(http://www.dmcknight.net/forumpics/hickory-erc/rough-in-2.jpg)
The cedar is so soft to work with compared to hickory! It's been really humid (85-90%), should I dry the cedar some in a box before gluing?
Also should I round the backing before I glue or does it matter at this stage?
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Your backing looks thick. I usually go 1/8" or slightly less.
It's always a good to dry the wood before glue up and it sure won't hurt. You can wait until the bow is glued up before rounding the edges but do it before stressing the bow.
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You have quite an eye! The backing is 9/64" thick. I can sand it down some more.
Also where the handle billet goes I had to shave off a 16th to fix a stray rasp gouge. I was planning to put hickory there, but now I'm considering adding a stack of thinner hickory plus a harder piece of cedar heartwood.
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txdm!!! Before you go any further, and sorry to be nosy, but are you SURE what you have there is EASTERN red cedar? It may be, but it looks quite brown in color, less pink than I am used to, the grain looks very straight. Around here fencing and roof shakes are split as often as sawn from western red cedar, which is an entirely different tree.
Just thought I'd check.
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I'm not entirely sure... it was purchased a long time ago. I'll look to see if some of the other boards have a tag on them.
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Well, shoot, I called the store where I got the lumber and it is indeed Western Cedar.
I have some Red Oak on hand, and also another cedar board from elsewhere that is much stiffer/denser, less gold-colored, and with more knots... It might be ERC, but I don't have a way of knowing for sure.
Final option is to be patient and find some real ERC locally when I am back in town.
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One sniff of your wood would tell you if it is red cedar as it has a very distinctive pleasant smell.
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Is western cedar unsuitable for a bow? If not I would go ahead with your plan, it may not look as cool, but it will look good regardless.
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Western Red Cedar is unsuitable.
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txdm!!! Before you go any further, and sorry to be nosy, but are you SURE what you have there is EASTERN red cedar? It may be, but it looks quite brown in color, less pink than I am used to, the grain looks very straight. Around here fencing and roof shakes are split as often as sawn from western red cedar, which is an entirely different tree.
Just thought I'd check.
That run off near midlimb looks bad to me, and it does not look like red cedar to me either.
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Back from the dead!
I acquired a nice board of real Eastern Red Cedar and have already cut it down to match my hickory laminates.
Is bicycle tube really the best way to go for glue-up? Does the tube get glued to the bow wood? I'll be buying the tube new, from either tractor supply or wallyworld.
My alternative materials on hand are 8 wood working clamps, and many many yards of heavy polypropylene hay bailing twine.
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I put masking tape on the back to keep it clean and then wrap the whole thing in Saran Wrap before I wrap the tube strips onto it. Take care to keep the Saran out of the glue line.
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+1 DC.
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Sounds good. I plan to put bamboo skewer dowels into the part of the handle that I will be cutting away later to hold the limbs stable during glueup. For the handle billet is it better to glue it before, during, or after the backing lam?
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For the handle billet
I'm not sure what you mean.
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I'm adding a 8" block of hickory board to make the handle deeper.
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When you add the handle block doesn't matter much, just make sure you aren't doing too much at once.
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Reporting back in... I DID eventually finish out this bow. I unfortunately thinned it down going by some measurements of another bow that is all hickory before bracing it, and it was pretty much a 35lb draw before tillering.
I find that tillering becomes harder and harder to get right the lower the poundage gets. At least that's my experience. The bow was eventually suffering from a hinge at ~30lbs, but shot quick with very little set. I think at 40 it would absolutely outperform my worn out 45lb all-hickory bow.
I learned a lot, including a new handle style and glue-on string nocks.
I plan to revisit this exact bow design once again after I have refined my tillering skills some more on basic board bows. This one has been set aside for reference at a later date.
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Well dang! Hope you post your next try. This was fun read-along. Betcha learned a bunch from the experience!
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Absolutely learned a lot. Here's a few pics of the bow:
(http://www.dmcknight.net/forumpics/hickory-erc/3.jpg)
(http://www.dmcknight.net/forumpics/hickory-erc/side.jpg)
(http://www.dmcknight.net/forumpics/hickory-erc/nock.jpg)
(http://www.dmcknight.net/forumpics/hickory-erc/handle1.jpg)
(http://www.dmcknight.net/forumpics/hickory-erc/handle2.jpg)
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One more pic I found of the glue up. Its wrapped in cling wrap and bike innertube. I let it dry for a few days during late summer.
(http://www.dmcknight.net/forumpics/hickory-erc/glueup.jpg)
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Did you have any trouble with the Titebond curing in plastic wrap?
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No trouble at all. It was at least 90°F in the shop (maybe up to 100°) every day, and I left it for 4 days at least before unwrapping. After all the outer edges were sanded down to the final shape there was a nice clean glue line all around.
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Good to know thanks.