View Full Version : selfbow build along
I know technically this should go in the buildalong section but being my first attempt ever, it may fail miserably. I figure, if it works I'll ask admin if they can move it there later.
Today I finally purchased a piece of 65x19mm spotted gum decking timber about 2.4 metres or 8' long. I'm intending to make a one piece flat bow/selfbow probably about 72" (leaves a bigger margin for error and gorilla arms:)).
The guy at the shop let me search through the pack but I found a fairly straight grained plain sawn piece straight away. Being paranoid, I searched for another 5 minutes to make sure but couldn't find any better but the first one was the best I could find.
Pictures will follow as I start shaping and tillering. I'm hoping to make a good start over the next few weeks on my holidays but it may be slow going after that (even during knowing me:rolleyes:)
Wish me luck. I'll keep you all posted.
Jono.
Looking forward to it Jono...I've tried a couple myself but get too impatient and take off too much timber but I am thinking about a re-run..
G/day mate , My son and I have been in the process of making a board bow for a couple of weeks now,be prepared for a few disappointments as I think we are now on our 3rd board,mainly due to being a bit to eager with the rasp ,but what we have leaned in that process is invaluable
Cheers Robbbo
Well, I didn’t have the greatest start. The in the middle of the night after I put up my first post in this thread, I woke up sick as a dog with a shocking case of gastro.
So, all I’ve done so far is take some pictures of the grain of my timber. It looks pretty good. Most of the length is totally straight along the board with just a slight run out towards one end. If you look really hard, the shot of the edge of the board (2nd img) shows the grain line running parallel to the board.
http://s49.photobucket.com/albums/f273/Hefty1982/?action=view¤t=2007-07selfbowbuild-along004.jpg
http://s49.photobucket.com/albums/f273/Hefty1982/?action=view¤t=2007-07selfbowbuild-along003.jpg
http://s49.photobucket.com/albums/f273/Hefty1982/?action=view¤t=2007-07selfbowbuild-along002.jpg
This afternoon (hopefully) I’m gonna mark out and cut the main shape at work and then bring it home for tillering.
Jono.
Toughen up Princess and get to it.
Looks like a good piece of wood mate, keen to see the progress.
Adam
Hefty, the grain doesn't look too bad, just go steady and don't be too impatient and remove too much timber at once, it is so easy to loose a lot of weight and end up with a 35-40lb bow.
Next time you buy some spotty go for the darker boards if you can find them, I have found them to be denser and stronger...Glenn...
Thanks Glenn, I'll do both those things!
Ok, today I took my timber into work (I'm a Tech Studies teacher) and started marking and cutting out. First I ripped the board down to 2" wide as it was a little bit over, then I cut off 2 x 1' pieces to glue together for the handle. The second photo shows a dried sap vein in one piece. I've used this piece in the handle because it will be removed in shaping to avoid a possible failure point.
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong009.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong010.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong011.jpg
Then I got onto marking out the board. It's 72" long x 2" wide x 3/4" thick. I marked a centre line down the length, I marked halfway and then I marked out the handle and the tapers to the tips, starting from 1' after the fades. One of the websites I found had some generalised dimensions for making flatbows so I've based mine roughly around them but i have had to increase their suggested handle height from 4" to 5" for my hand. The handle is 1" wide and returns to full width over 3" either side(these will also be the fades of the thickness of the handle when it is glued on). I've also included marks for a possible shelf but haven't made a final decision as to whether I'll include it or not.
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong013.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong014.jpg
By the time this was done, the handle pieces were dry to mark out and cut.
After marking out, I cut the side profile on the bandsaw and used the disc sander and belt sander to ensure the fades were feather thin on the ends where they would join the rest of the bow. I also cut the tapers while I was at the bandsaw.
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong015.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong016.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong017.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong018.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong019.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong022.jpg
Then I transferred the centre height lines of the handle and the rest of the bow onto the sides and used these to line them up for gluing and clamping.
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong020.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bowbuildalong021.jpg
I also made a tillering stick but didn't take any photos yet. I'll try to remember to put one in my next post.
Having written this, the handle glue should be dry for me to cut the width and I'll include that in my next post too!:D
Jono.
Looking good dude, whats the distance from center bow to arrow plate(shelf).
And what glue are you using.
Adam
2 and a half inches to the shelf (it's just right at the top of the handle and the handle is evenly spread over centre) and I'm using PVA glue. I don't even know if it's appropriate for the job but that only occurred to me after I'd glued it all up.
I know laminate bows use epoxy but I figured there should be less stress through the handle than the limbs so it should be strong enough. (man I hope I'm right:()
Jono.
XTfreak
02-07-07, 07:10 PM
Looks good so far.
Looking forward to it Jono...I've tried a couple myself but get too impatient and take off too much timber but I am thinking about a re-run..
Hey man I think you should give it another try. Iam starting on one next week, and then we could compare them on the group hunt in August...
Bill
You must get a sore back doing that bro.
They still haven't raised any of those school machines to a good working height, hey?
Looking good.
Joel.
Not for you freaks anyway, the tables are normal height;)
Thanks for the info bro, How about the center line, holding the bow vertical what the horizonal measurement for center to rest.
Adam
Looking good Jono, if the p.v.a. glue doesen't hold it's no worries to reglue it with epoxy. Are you making your bow with equal length limbs...Glenn...
Thanks for the info bro, How about the center line, holding the bow vertical what the horizonal measurement for center to rest.
Adam
Looking good Jono, if the p.v.a. glue doesen't hold it's no worries to reglue it with epoxy. Are you making your bow with equal length limbs...Glenn...
Adam, I'm still trying to finalise that. I haven't cut the shelf yet and since writing that the shelf height from centre was going to be 2 1/2" yesterday, I have reduced it to about 1" or 1 1/4" (it turns out I didn't need a full inch extra for the handle to fit my hand:rolleyes:). In my limited reading so far I've had difficulty finding suggestions for measurements for centre line. I'm reading a book by Sam Fadala where he mentions as little as 3/16" in some longbows and other one piece bows but I don't think I can get it that close for fear of weakening the handle too much. At this point in time it is just 1/2" from centre to outside of handle. I'm still trying to decide if I should add a shelf (attach a separate piece of timber) or cut one in. I know the further from centre, the more the arrows will be affected by the archer's paradox but I'm not sure how to quantify that into an appropriate distance from centre.
While I'm here, Glenn or Perry, what would you guys recommend?
Glenn, the limbs are equal length at the moment. Am I correct in saying that if the limbs are the same length and the shelf is above centre I'll need to tiller the lower limb slightly more than the top limb to get equal power out of the limbs to the arrow? Or would it be easier to alter one limb length slightly?
I'm loving this but each step brings so many more possibilities and questions!:confused::D
Jono.
While I'm here I might as well put up my latest few photos.
After my post yesterday, I cut the width of the handle on the bandsaw while I was still at school.
http://i49.photobucket.com/albums/f273/Hefty1982/2007-07selfbowbuild-along009.jpg
I also took these photos of the tillering stick I made. It's just a piece of 19mm x 42mm pine with a cradle shape cut in one end and small cuts to hold the string at 1" intervals (I haven't rounded the string grooves yet)
http://i49.photobucket.com/albums/f273/Hefty1982/2007-07selfbowbuild-along010.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/2007-07selfbowbuild-along013.jpg
After that I took the bow home and yesterday and this morning I've been rounding all the edges and shaping the handle
http://i49.photobucket.com/albums/f273/Hefty1982/2007-07selfbowbuild-along006.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/2007-07selfbowbuild-along007.jpg
The shape I came up with for the handle is fairly simple (and chunky, I may still take a little more off), it's virtually broomstick style for a low wrist grip with just a small locator at the top. Shaping the handle section to my hand is what made me realise that I didn't need a full inch extra for my handle.
I'm still working by floor tillering but I went to Eagle archery today, bought a stringer and asked if they had any strings long enough for me to use as a tillering string for it (eg 68ish"). They had no normal strings long enough but in the best act of service I have had from Eagle yet, Mike let me borrow an old fast flight string (for tillering only, if I shot this bow with a fast flight string it would break real fast) that I can use on the tillering stick to check the curve of the limbs as I remove material. I'm stoked! So the next few days will be an exercise in patience for me so that I don't take off too much at a time from either limb.
Jono.
Ok, so today after a few days of careful shaping,removing timber from the edges of the limbs in very initial tillering, the glue finally gave way on the handle while I was floor tillering (holding the bow at the top and pushing the handle to check how the lower limb flexes against the floor).
So Glenn, what kind or brand of epoxy would you recommend?
Over the next few days I will start more significant tillering, working the flat surface of the belly, but I can't do too much until I re-glue the handle because currently it flexes too much there.
The limbs are still very stiff. Becuase I've only been removing timber from the edges so far, the first half of each limb is still close to full width and still 3/4" thick. It doesn't even flex enough with the bow stringer to put on the tillering string I have on loan from Eagle Archery!
More to follow in the next few days.
Jono.
Jono I always use Techni-glue epoxy for bow building.
If your limbs are of equal length and the arrow shelf is above centre then you will have to make the top limb slightly stiffer than the bottom limb to balance the limbs or negative tiller.
When you make the bottom limb shorter than the top then you make the bottom limb stiffer or positive tiller.
A bow with a shorter bottom limb will be a better balance bow for both dymanic and static balance...Glenn...
Cool, thanks Glenn!
I'll have to get myself some Tehni-glue and I think I'll go with the shorter lower limb. It sounds like that will involve less "guesstimation" in comparing the stiffness of each limb.
The rest will be 1 1/2" above centre so I'll re-position my lower string groove and cut the limb to the lowest point of the original string groove, shortening it by 3/4", effectively centering the shelf.
Jono.
Jono, th best way to achieve the shorter bottom limb is to mark the centre of the stave and then mark 5/8th of an inch above centre and then mark roughly 2 inches either side of the off centre for the handle. This will give you a bottom limb which will be 1&1/4 inches shorter than the top limb...Glenn...
My next question is, where can I find Techniglue?
I've googled it and found out all about it but not where to buy it and I checked bunnings and I went through the yellow pages but I still couldn't find it.
Oh, and I've slowly started working the belly and can already notice a difference in the curve.
Jono.
Mate my local woodwork shop sells it so try them if you have one in your area.You can also contact http://www.ausbow.com.au/bowmaking.html htye are very helpfull with all bow building stuff and stock that glue.:)
I think he is going away soon though so give him a ring.
Cheers KIM
Cheers Kim!
Well, I had to take the second half of last week and the weekend off bow making coz I had to did out some stumps (got some killer blisters) and put in our new colourbond fence (It looks awesome!) so I'll be looking for local woodworking shops this week and doing a little more tillering while as I prep the handle for re-gluing. Might be a little longer between posts from here coz I'm back at work from today.
Jono.
Carba-tec here in Brisbane sells Techniglue Jono, try this link:
http://www.carbatec.com.au/store/index.php?main_page=index&cPath=111_11780
It sounds like your project is really coming along mate but do you really think that your making the bow long enough for that albatross like arm span of yours?
Maybe you should change the length to a 7 foot long bow just to be safe.:P
Thanks Paul!
LOL, yeah, I'm pretty sure it should still reach my draw length! It'll probbaly stack like a deck of cards tho :(
Jono.
Looks like it's coming along a beaut Jonno! :D
Can't wait to see it in the real when it's done.
Cheers Luke!
It's gonna get a bit more frustrating now that I'm back at work. I haven't worked on it for a week now.
Hopefully I'll be able to get to carba-tec this weekend and get the techniglue. I really can't afford to do too much more tillering until I glue the handle back on because the flex through the handle would change the curve of the bow.
Jono.
Hanging out for the next installment Jono!!!
Well guys,
I'm back on holidays and finally able to spend some more time on the bow, so what's the first thing I do?
I get the bow about 3 cm from being able to be braced and I HEAR A SNAP IN THE HANDLE!!!!:mad::(
So, I went back to timber store and bought a grey ironbark board instead of spotted gum (just coz they happened to have it in stock this time) and I'm gonna start again, putting all the stuff I learnt from the other bow into this one. Hopefully I'll get some pictures up soon.
Jono.
Oh well that happens with selfbows Jono, better luck next time, the grey ironbark is tough timber. Are you building a flatbow or an English longbow. If you are doing a flatbow maybe you could trap the back and make it narrower than the belly, same with the spotted gum because both of these timbers have a high mechanical figures for the tension on the back even though their modulas of rupture figures for the belly is very high as well...Glenn...
I think I know what you mean Glenn but I'm not entirely sure.
I made a diagram of the cross section of a limb. Is this what you mean? (ignore the sharp corners, it was a 2 minute job in paint:P)
http://i49.photobucket.com/albums/f273/Hefty1982/bowcrosssection.jpg
If so, I'll give it a try as I rough down the shape.
Thanks!
Jono.
That's it Hefty, that's the safest way to go and reduces limb mass as well which is another positive...Glenn...
Ok, here's what I got through in the holidays.
Now that I finally got some techniglue, I can move a little faster and I've also re-glued the handle of the first one to see if it can be saved.
Here's the new piece. It's grey ironbark. Not perfect grain but the best I could find in the stack:
End Grain
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowbuildalong025.jpg
Grain along 19mm edge
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowbuildalong026.jpg
I marked out on the back according to the same dimensions I used for my original (see earlier posts in this thread) with one change as suggested by Glenn. I made a 1 1/4" shorter lower limb by marking a handle centre 5/8" lower than the true centre with the handle marked 2" eitgher side of this new offset centre.(sorry about the flash)
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowbuildalong029.jpg
I then used techniglue to glue two extra thicknesses for the handle section.
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowbuildalong038.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowbuildalong027.jpg
One woodworker's forum I visited reccommended not clamping too tightly as this can force out too much glue and "starve" the joint of glue. The glad wrap is to stop any leaks from sticking the whole stave to the bench.
Once this cured (overnight) I took it into work and cut the rough shape of the limbs and handle on the bandsaw.
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowbuildalong033.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowbuildalong034.jpg
Then I brought it home and I have been working on the overall shape with the plane.
Initial work on the handle:
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowbuildalong037.jpg
I have also started working the limbs down with the plane to get the back narrower than the belly (see earlier advice from Glenn) but following Glenn's advice, I will stop using the plane very soon to avoid tearing out too much timber when I'm approaching the required draw weight because the grain isn't perfect.
From there onwards I'll be using a wood rasp.
I'll have more photos as the wrok progresses!
Jono.
Antarcher
08-10-07, 04:08 PM
Looking the goods Hefty. Looks like you'll be finished in no time. Looking forward to see how she shoots once it's done. What are you going to name it?
Looking good Hefty, will be good to see it braced...Glenn...
Name it? I hadn't even thought of that yet! I'll have to get back to ya.
Jono.
well what happened with it, was it a shooter?
Sorry Ed, It's still being built but unfortunately what was supposed to be something I could work on continuously until it was done has become something I have to pick up where I left off each holiday.
Today was my last day at work so hopefully the longer break should see me finish it. I might even have time to re-work the handle of my first attempt, get some glass and back it to see if it can be salvaged.
Jono.
NormGunston
07-12-07, 01:07 PM
Best luck with that (Mk II) project over the holidays, Hefty. We're getting much vicarious enjoyment through this! Have you made a tiller tree yet?
No, haven't made a tiller tree. That's the thing you put it on to compare the curve of both limbs isn't it? I've got a sheet of grid drilled masonite that hopefully I can draw it in front of to view the curve of the limbs.
I have made a tillering stick tho and I'll use that and a set of scales to get an idea of it's weight.
This one is turning out more longbow-ish than the other one because I've tried to keep some more thickness in the limbs. The first one is a more flatbow shape.
Anyway, I've got some photos that I'll post in the next few days but for now I'd better get back to it!
Jono.
Looking forward to see some photos Jono...Glenn...
Ok, so here's where I'm up to:
I've worked the limbs down a lot more than I thought I would need to.
As I mentioned earlier, this one has taken a longbow-ish shape because I've taken more off the width than the thickness.
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowpics001.jpg
You can just make out the handle in the middle between the two slightly wider shoulders.
I've decided to put a shelf in this attempt so I cut that in just above the handle. (you can see the glue line on the end of the fade. I need to work that back just a little bit more)
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowpics003.jpg
My next step was to put in the string grooves. I marked them with a pencil 1 inch from the tips on the belly side. They slope 45 degrees towards the tips from belly to back.
I forgot to take a picture of the pencil marks but here's a shot of the initial cuts with a tenon saw:
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowpics004.jpg
And here they are after being worked with a small rat's tail file:
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowpics007.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowpics008.jpg
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowpics009.jpg
At this stage I have not cut them into the back to keep thickness for strength. I will test it very carefully when I first come to brace it to see if the grooves need to go across the back as well.
I have also taken Glenn's advice and kept the back narrower than the belly to make the most of the properties of the wood. This is easily seen at the tips (where it is almost overdone:o) :
http://i49.photobucket.com/albums/f273/Hefty1982/bow%20build%20along/bowpics006.jpg
Anyway, now I have to order the flemish twist string I was going to get ther other day because I discovered my local store isn't trad enough to make them.
I'm getting excited. I should be able to brace it really soon!
Jono.
Looks Good Jono, I like the fine lines of the bow. I would much rather narrow a selfbow rather than make it thin it down too muck from back to belly. You shouldn't need to file string grooves across the back, the side string grooves should do. On bows that I have made very thin on the tips I don't bother with string grooves on the side at all and just just file a string groove across the back of the bow, I usually glue some overlays on the back when I do that or just leave extra thickness there. Will be good to see how the tiller goes...Glenn...
Well, I got back from a week's holiday at Coolum to find a dacron string from Jeffro in the mail!
http://i49.photobucket.com/albums/f273/Hefty1982/IMG_4360.jpg
It looks fantastic and I'm keen as to get it on.
I had some pictures ready to post of the initial curves on the tillering stick approaching brace height but my wife downloaded them on our non-internet-connected computer to make room on the camera and I didn't know.
So, when I get them ont this computer I'll post them too!
Jono.
Well, here's the first shot of the bow on the tillering tree. I've gotten a few inches closer to brace height since this photo (I'm looking at a 9" brace height because it's 70" groove to groove)
http://i49.photobucket.com/albums/f273/Hefty1982/IMG_4368.jpg
I'm working more on the ends than near the centre at the moment to get a good even curve.
Jono.
Jono, make sure you have the bow supported on the tiller stick exacty where you are going to place your hand on the bow when you shoot it and draw your string down from the same position as if you are drwaing the bow with an arrow nocked. If you don't do this then you will never see the true bend of the limbs when the bow is being shot and the bow will quickly go out of tiller and one limb will take more set then the other and the bow will go out of tiller very quickly and she will be rough to shoot...Glenn...
Cheers Glenn, yeah i've been putting the stick in the same spot each time.
Unfortunately it's all academic now as a little while after putting up my last post, I attempted to brace it for the first time and i got failures in both limbs about 8" either side of the handle.
It's almost enough to make a grown man cry. I'll post some photos soon because I want to see if you guys can tell me the specific cause. Ie Did I get to brace height to quick? Were the failure points too thick for the curve? both? neither?
Anyway, I'll also post pics of my first attempt with the re-glued handle because it is already close to bracing without failing too. Maybe i can avoid more failed limbs and firewood. :(
Jono.
Grunter
16-01-08, 06:48 PM
Jono,
I could se myself shedding a tear or two with the effort that has gone into the bow. But at least you can put it down to a learning curve.
Jono, when you brace a bow for the first time it is usually best to brace it low to start and go through the tillering process back to full draw. Then take the brace height up 1 or 2inches again and check the tiller again back to full draw and make any necessary corrections, and keep repeating this process until you can brace the bow at the desired brace height. I never brace a selfbow over 6.5 inches. They shoot well at the brace height and doesen't seem to over stress the bow. A lot of selfbows fail because they have been over drawn and over braced. You will get more performence from any traditional bow that is shot on the lowest brace height possible because of the longer power stroke...Glenn...
Ok, here's the ironbark bow braced:
http://i49.photobucket.com/albums/f273/Hefty1982/IMG_4395.jpg
I think it looked awesome :D until it broke :( This is one of the points where the limbs failed (I had another photo of the other side but it stuffed up):
http://i49.photobucket.com/albums/f273/Hefty1982/IMG_4398.jpg
This is the spotted gum bow approaching brace height:
http://i49.photobucket.com/albums/f273/Hefty1982/IMG_4419.jpg
And here it is first braced:
http://i49.photobucket.com/albums/f273/Hefty1982/IMG_4436.jpg
It's at 6" and I'll check the tiller out to draw length (if it doesn't fail too) and possibly put some twists in the string to get slightly higher but I know it won't increase it much.
Here's to hoping it doesn't fail as I slowly check the tiller towards full draw!
Jono.
Hefty you need those limbs bending off the handle, don't have them stiff near the handle as it will place a lot more pressure on the mid-limb section creating extra string follow. Try and get the limbs bending the most down near the handle section and have the limb bending all the way to the tips but they need to bend gradually less towards the tips. This way you are distributing the weight and storing energy all along the limbs length but storing the most down near the hanlde where most of the timber is in the limb to take the pressure when drawn...Glenn...
I haven’t looked at this post for a while and after reading about the limb failures I don’t think I could ever bring myself to have a go at making one. It’s just too heartbreaking.
Like raising a child that turns out to be a psychopath! :(
It's like seeing your firstborn child - only it's a goatboy named Mozza...
Clemo you have to be a bit psycho to build selfbows, if you arent when you start they quickly send you around the bend, they never stop testing and changelling you to make the next one better then the last one..Glenn...
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