3 piece or 5 piece core?

[JonW]

I'm going at this real slow. Been reading all I can and am ready I think. For the first bow would you do a 3 or 5 piece? I'm not intimidated by splicing. I actually think the bending sounds more challenging than the extra splicing.

[RBLusthaus]

Ive been working on the 3 piece, and can say that the required bend is substantial.  Not an easy flip of the tip type of bend.  Many broken laths so far. 

The five piece seems more difficult to keep a straight and flat center line - - but I have not tried it yet. 

Real issues both ways. 

Russ

[JonW]

Russ I think in my mind I have the centerline issue worked out. I say THINK because I have tried splicing just plain slats and it seems that it works.

[Tc]

I have tried both and found 3 piece construction to be safer and more stable. What bow type are you going for? I think 3 piece core is ok for most of the style, unless you are making a mugal bow.....
On this photo all of them are 3 piece core (except the turkish) altough bending was pretty complicated with tatar.....

[JonW]

Tc I was going to try a Magyar to start with.

[mikekeswick]

5 piece is easy enough to keep everything straight it also way easier to get the wood in the first place.I'm onto my third now.
3 piece cores are fine but you must get everything dead right for a successful bend. Make 100% that the wood is as near to perfect as you can get.

[Tc]

I think bending is a must, especially if you want to avoid stringfollow later on.....If the limb is straight (no matter how you bend or glue the limbs at the grip) soon or later the bow develops a certain degree of stringfollow. If you give the limbs some bending (or reflex if you like) before glue up the horn, no stringfollow...
This is what I am talking about:

[mikekeswick]

I agree to a point but think whats happening to that glueline on a reflexed bending section. Much better to keep the reflex in the non-bending sections.

[Tc]

If the glueline is in the neutral zone - nothing. It will hold. Just think of the korean bows, they are a big bend

[mikekeswick]

Yes that's what I said. Korean bows have a large radius bend in the bending section, plenty of grip reflex and again in the kasans also pretty reasonable tip reflex. My last hornbow has a fair amount of reflex in the bending section BUT there comes a point when the forces will be too high. Putting excessive reflex in the bending section will cause delamination.
The neutral plane has no compression or tension but it definitely doesn't feel 'nothing', there are strong forces of shear working on the glueline.

[JonW]

I understand you want reflex to counteract the possible string follow. I also know from making selfbows that more is not always better. I want my first to be successful. Can't you get plenty of reflex from splicing? I'm not looking for the fastest possible design but the one that will work for a noob.

[PatM]

Splicing will just give you set-back, not actual limb reflex.

[james parker]

  Pat M ,,that depends,, my splicing goes far into the limbs where actual reflex is induced, therefore  the  splices and reflex are blended together

[PatM]

I only meant when people just set the handle back and then don't do anything to the limb  as seems to be suggested.