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Main Boards => The Bowyer's Bench => Topic started by: Shaun on December 10, 2011, 03:04:00 PM

Title: ELB build along - osage
Post by: Shaun on December 10, 2011, 03:04:00 PM
This stave was about 1 1/8" square by 72 1/2 long. I drew a grain follow center line - this piece is clear but wavy. Then I marked 5" increments from the ends and laid out profile with each segment 1/8" less in width. This makes the center about 1 1/16" tapering to 1/2". The first pic shows this profile cut and the same taper laid out on the side profile.  I cut the top lay out square to the back (chased ring) surface.

 (http://img.photobucket.com/albums/v613/shaunw/ELBhowto001.jpg)

Make the same tapering layout on both sides and cut with approximately 10 degree lean of the back surface. This prevents cutting too deep on the opposite side where the wood is twisted. After making cuts from both sides you will have a ridge in the middle of the belly.


 (http://img.photobucket.com/albums/v613/shaunw/ELBhowto002.jpg)

Application of power rasp (edge sander) removes this ridge and general shaping towards the arched belly shape and general view towards leaving a tapering in both width and thickness from center to ends.

 (http://img.photobucket.com/albums/v613/shaunw/ELBhowto003.jpg)

With the bow flipped back side up you can see that this stave is not straight. Since we are headed for a rounded shape (ELB rule is that the bow can be no more than 8 to 5 ratio of width to thickness) it is MUCH easier to tiller a straight stick. A flat bow resists bending sideways - much less so in a rounder shape.

 (http://img.photobucket.com/albums/v613/shaunw/ELBhowto004.jpg)

So, onto the cull with heat gun and clamps.

 (http://img.photobucket.com/albums/v613/shaunw/ELBhowto005.jpg)
Title: Re: ELB build along - osage
Post by: Shaun on December 10, 2011, 03:06:00 PM
I like to use a piller tiller system before brace height. This allows me to get back and sit looking at the arc, then mark with pencil and take off wood where there is less bend, flat spots. Here is the stick off the cull with induced backset and nearly straight.

(http://img.photobucket.com/albums/v613/shaunw/ELBhowto006.jpg)

My belief is that you can do little harm to the stave before reaching brace. The bar clamp allows continuously variable draw and is more solid than using a long string on the tree or a tiller stick. Here is the first bending. As always, stop as soon as you can see a flaw in tiller and correct.

(http://img.photobucket.com/albums/v613/shaunw/ELBhowto007.jpg)

I see flat spot in the center and about 1/2 way out the right limb.
Title: Re: ELB build along - osage
Post by: Shaun on December 10, 2011, 03:09:00 PM
Correct and repeat process until the arc is pleasing.

(http://img.photobucket.com/albums/v613/shaunw/ELBhowto008.jpg)

Still a little flat in the center, just to the left of center, and last third of left limb, but getting real close. At this time I return to the heat gun as some of the original waviness has reappeared  during tillering - this is common with heat adjusted wood. These smaller and area specific adjustments are made one at a time on the bench.

(http://img.photobucket.com/albums/v613/shaunw/ELBhowto009.jpg)
Title: Re: ELB build along - osage
Post by: Shaun on December 10, 2011, 03:13:00 PM
After re straightening, continue adjusting tiller on the posts. I switch from 40 grit to 100 grit on the edge sander and start to work on smoothing and tapering in both width and thickness as the tiller progresses.

(http://img.photobucket.com/albums/v613/shaunw/ELBhowto010.jpg)

When it gets this close I cut string nocks and try first brace. I use the pillers to brace as the bow is still to heavy for push pull hand stringing. Love the moment of first brace!

(http://img.photobucket.com/albums/v613/shaunw/ELBhowto011.jpg)

With this method 90% of the build is completed before the bow is ever drawn past first brace. Now is the time to put it on a tiller tree and/or start shooting it in. As the wood is worked it will change and need re adjusting of tiller. This is also the time to check draw weight and start reducing towards desired finish weight and refining aesthetic lines. Also, minor adjustments of limb alignment will be needed by either heat or tillering (cutting material from off center of the width will make the limb bend towards that side). Here is the bow nearly complete - needing finish smoothing and more shooting in with minor adjustments as they appear.

(http://img.photobucket.com/albums/v613/shaunw/ELBhowto012.jpg)

(http://img.photobucket.com/albums/v613/shaunw/ELBhowto013.jpg)

This bow is still slightly heavier than the mid to low 50's I want, but final tiller adjustments and sanding will bring it in. Time to shoot it a bunch and get the wood to finish settling in to its working shape.

(http://img.photobucket.com/albums/v613/shaunw/ELBhowto014.jpg)

Another note; I mentioned the ELB ratio of 8/5. The center of the limb is under more twisting stress than the hand held center or the tips, so this area is often shaded more towards the 8/5 flatter profile and the handle and tips left round. This makes the limb cross section progress from round center to flatter mid limb and back to round at the tips in most ELB bows.
Title: Re: ELB build along - osage
Post by: Shaun on December 10, 2011, 03:14:00 PM
Further thoughts on piller tiller system: Before bending past fistmile brace height little set or fiber damage is likely because so little deflection has been made. It is yanking a bow back to 20" while it shows tiller flaws that induces set and hinging. By correcting tiller flaws in the very early stages of bend this is avoided. It does leave the wood untested and further bending will create new flaws as the fibers stretch. These need to be corrected as soon as they show during the working in by shooting (short draw) or working on the tiller tree. In the first brace picture on the posts, the arc looks nearly perfect. This will change as the wood works - that is the last 10% of tillering required until full draw is reached.
Title: Re: ELB build along - osage
Post by: K.S.TRAPPER on December 10, 2011, 04:04:00 PM
Pretty cool Shaun  :thumbsup:  

You make it look easy  :D  

Tracy
Title: Re: ELB build along - osage
Post by: 4est trekker on December 10, 2011, 04:40:00 PM
Love that tillering idea!  I've never seen it, but it does make a good deal of sense in many ways.  Thanks for sharing.
Title: Re: ELB build along - osage
Post by: Dan Landis on December 10, 2011, 06:00:00 PM
Thanks for the build along Shaun, I'll be trying the piller tiller on my next one.....Dan
Title: Re: ELB build along - osage
Post by: Stiks-n-Strings on December 10, 2011, 06:29:00 PM
Great build along Shaun. I'll have to try that tillering method (minus the sander, as I get in a hurry to often as it is)

Can you post some pics of the 2x4 stands and give us some measurements?
Title: Re: ELB build along - osage
Post by: KellyG on December 10, 2011, 07:03:00 PM
that is one great looking bow.
Title: Re: ELB build along - osage
Post by: coaster500 on December 10, 2011, 07:39:00 PM
I've got a chunk of Sassafras to practice on...  I'll give it a try.

Thanks again for posting  :)
Title: Re: ELB build along - osage
Post by: snakebit40 on January 04, 2012, 11:01:00 AM
:thumbsup:  Really cool way to work out your tiller. Thanks for sharing!
Title: Re: ELB build along - osage
Post by: Buemaker on January 04, 2012, 11:55:00 AM
Thanks for sharing, I must say it is an interesting tillering method, I am gonna give it a try. Bue--.
Title: Re: ELB build along - osage
Post by: 4runr on January 04, 2012, 12:39:00 PM
Sweet looking bow Shaun.

A local fella has got me thinking about building another bow. I like your method.
Title: Re: ELB build along - osage
Post by: Walt Francis on January 04, 2012, 02:41:00 PM
Shaun,
That is a great build along.  I love the tillering method and will give it a try this winter.
Title: Re: ELB build along - osage
Post by: Osagetree on January 04, 2012, 04:53:00 PM
Me too!
Title: Re: ELB build along - osage
Post by: mwosborn on January 04, 2012, 08:23:00 PM
Thanks for sharing - I to am going to try the piller tiller method.  You do make it look easy!!
Title: Re: ELB build along - osage
Post by: Roy from Pa on January 04, 2012, 08:44:00 PM
Shaun, that is fantastic. I love the concept, a very ingenious idea. I will be trying that real soon. Thanks, Roy
Title: Re: ELB build along - osage
Post by: Living_waters on January 05, 2012, 11:34:00 AM
Thanks shaun!
I just brought home some white oak staves to make some incised decorated Delaware bows out of and the bendy handles have been my nemesis, either I end up whip ended or too stiff in the handle. This looks real promising as a solution for me.
Title: Re: ELB build along - osage
Post by: cooper2003 on January 08, 2012, 12:00:00 PM
Nice build along. This is the type of bow I am hoping to make as soon as I master a few board bows.  :)
Title: Re: ELB build along - osage
Post by: Tom Leemans on January 13, 2012, 10:34:00 AM
It looks like before you start hitting it with hand tools you are pre-tillering, like we do when making the rattan kids bows, except the ridge ends up on the back with those. Same concept on the saw though. Tip it up off the table a bit and follow the profile. Maybe that's what I'll do with my tollhouse stave I got from Timo years ago! I love the tiller on those ELBs you've done.
Title: Re: ELB build along - osage
Post by: Paul/KS on January 14, 2012, 09:46:00 PM
I split some staves today before work that just might be good for a bow like this. Thanks for posting the build along...
 :thumbsup:
Title: Re: ELB build along - osage
Post by: Paul/KS on January 15, 2012, 01:08:00 AM
Oh, and I love that great cabinet makers bench that you have too.   :)
Title: Re: ELB build along - osage
Post by: razorback on January 15, 2012, 09:43:00 AM
Well I think I may jump on the band wagon and give this a try. Got an osage slat that I need to pretiller for a bamboo backing. I think it may be the perfect candidate.

Do you do the tillering while it is bent on the pillars or do you take it off and do the work unbent.
Title: Re: ELB build along - osage
Post by: BMN on January 15, 2012, 09:57:00 AM
Nice work! Thanks for sharing.
Title: Re: ELB build along - osage
Post by: Pete W on February 13, 2012, 01:44:00 PM
Great Idea, and now I just found a use for a Bow press I made many years ago for the wheel bows. It is no good for the modern wheels, so I couldn't even give it away but hated the Idea of throwing it out.
For Pillar tiller it just needs to be extended on the base, and the rubber boat trailer rollers will work good for a cushion on the tips.It is adjustable for width too, so I will be able to use it on all lengths of bows .
Thanks for the inspiration.
Pete
Title: Re: ELB build along - osage
Post by: mwosborn on February 13, 2012, 11:36:00 PM
Pictures Pete!
Title: Re: ELB build along - osage
Post by: Eric Krewson on February 14, 2012, 08:33:00 AM
Made a zillion bows but never made a true ELB. You have inspired me, great bow.