72" yew war bow

[duffontap]

Jaro/Yeomanbowman,

Do the Mary Rose bows show parallel growth rings on the back (like they were intentionally 'crowned') or were they made from crowned staves to begin with?

Also, Pip has described some of the bows as having a fairly classic D-section.  Were there no such bows?  My Mary-Rose bow has a section slightly more rectangular than:


My most recent war bow as a narrow version of this:


         J. D. Duff

[Yeomanbowman]

Hello J. D,
I recall Roy king talks of the Mary Rose 'edge' caused by this process and there are so many styles that I'm sure some must have been a Victorian type 'D'.  However, all of the bows I have seen on display in Portsmouth 'in the flesh' have backs that are no more crowned than the unworked staves.  The bows seem to be from relatively small diameter staves.  I think that most of the bows still have some cambium left across most of the back.  I understand that the 2 heaviest bows are rectangular sectioned.
Have a llok at these images I took.
http://i138.photobucket.com/albums/q280/yeomanbowman/DSCF0016.jpg
http://i138.photobucket.com/albums/q280/yeomanbowman/DSCF0012.jpg
Cheers,
Jeremy

[D. Tiller]

Jeremy, those are cool picks! Next time your there do you think you can get some picks of the sapwood vs heartwood?

When they were making these bows did they aim first to get a rectangular shape and then round off the edges on the Mary Rose bows?

David T

[Yeomanbowman]

Hello David,
The answer is I'm not sure, sorry.  There were so many bowyers (bowyers marks) I believe that there may well have been many processes.  Chris Boyton has a theory that some sort of planing jig was used to rough out the bow's width quickly.  On a batch produced item it would seem to make a lot of sense.  One thing I have done in the past is to use a more D than rectangular section if the stave was a bit too triangular when split.  Wasted staves = lost profit, I suppose.  I'm sure by steaming and the fact that  side nocks/double timber hitchs allow bent bows to be centred, very little wood was unusable.
Cheers,
Jeremy

[duffontap]

Thanks for posting those great images Jeremy.  Man I want to get my hands on those bows.  I feel like I need to see and hold them for a while so I can understand a little more about how they were made.  Thanks for the great information. 

         J. D. Duff

[SimonUK]

Hi Jeremy

Cambium on the backs? Does that mean the sapwood was left full thickness? I tried making a bow like that but it was all sapwood at the tips.

[sagitarius boemoru]

"Full thickness" of sapwood on a small diameter stave with high ringcount is still very thin layer. (Well because the rings are thin - right?)

But yes - the logs they cut for staves were relativelly small diameter which causes the back of the bow be crowned and the rings running semicircular in the profile.

Your squared profile is too much squared. The squared profile on MR bows i more oval with small flats on sides and we have genesis of this. It looks more like normal oval profile blown up over the dimensions of squared stave, if you copy me.

You start with a squared stave and make width taper, then you make thickness tapper, all based on experience, then you facet sides from belly to side, but not in 45 degree angle, but somehow  less.
Then you round belly up to the facet - and the small flat surfaces on sides of your stave will magically appear.
Then you tiler only thickness and wont touch anything else.


Jaro

[SimonUK]

I have a question about rounding off the corners of the back in areas where there are clusters of pins.

The yew stave i'm working on has clusters of pins (covering about 1 or 1.5 cm square) at various places along the back. If I round off the corners of the back, what should it do at these places?

Option 1: don't round off so much at these areas therefore making it stronger
Option 2: do what it says in the Bowyers Bible concerning decrowning and keep the growth rings parallel when viewed from the back
Option 3: leave a couple of extra growthrings at these areas and round off to the same degree as the normal areas of the back. This will mean the view from the back will show the growth rings bending a bit and skirting around the area of pins.

Any ideas anyone?

[Pat B]

After a bit more work I got her to brace and since yesterday I have brought her to where she is now. From the pics I can see the top limb(left) is bending too much at the handle area and not enough out the limb.  Right now she is pulling 87#@26". I know she won't make war bow weight but at least maybe I will be able to shoot her.   The first pic is at 5 1/2" brace, 2nd is at 24" and the 3rd is at 26".
   I have rounded the back as suggested and would like some more suggestions on where to go from here.  Please be honest...but gentle     Pat

[attachment deleted by admin]

[Matti]

Pat,
The tiller is not in balance. I would remove wood from the left limb tip and from the first 3rd of the right side. Then it'll be pretty close to ready.

BTW, from my short experience with heavy bows I have noticed it's best to first make sure the limbs are symmetrically bending and the tips bend also. The middle of the bow can be a bit stiff because it will bend only at full draw. That's why it's wise to save the handle area for the last tillering touches.

[duffontap]

Matti,
Bickerstaffe recommends leaving the taper of the tips for the final stage.  I don't have a preferred method myself.  I just try to keep the tiller right through all stages (with varying degrees of success).  I agree with your assessment of the tiller, of course.

Pat,
Sounds like you know what to do.  Finish up the left limb and sand it.  Then take some Ibuprofen and shoot a 1,000 grain arrow.

              J. D. Duff

[Justin Snyder]

Pat, Is the left limb supposed to be 2" longer?  Justin

[Pat B]

Justin, The bow is set up with the top of the handle(4" area) set at 1" above center and the bottom of the handle is 3" below.
  Thanks Matti and Josh. I'm too pooped today but later I will work on the upper limb a bit and see where I am.   Josh, First of all I don't have a 1000 gr arrow (will 2, 500s do? ) and second, I can pull this thing maybe 10" .  I'm afraid if I pull too hard I will have to get my hemis tuned!     Pat

[Kviljo]

If it is 87 at 26 it will probably be 110 at 30 or 125 at 32.
So I would call that one a warbow with confidence

A bit adjustment and you got an awesome bow there

[Pat B]

Thanks Kviljo. We will see after I adjust the tiller.   I doesn't matter to me if she hits 100# or not. I have enjoyed the experience of working such a wonderful yew stave. This will probably be the only war bow I build. When done, I will give her back to the guy that gave me the stave in the first place. He will be able to shoot her.     Pat