Help, I cracked a riser.

[garyschuler]

I have always had some type of issue with Black and White Ebony. Prone to cracking. Separating, fine line splits. Not my fav wood. My thoughts anymore, when in doubt - I-Beam it, you can do a full length beam or a hidden beam.

[Kirkll]

You are right, I didn't want to see the beam so I didn't do it. That one extra step cost me bow..... kicking myself, I had even cut 2 strips of that ebony to beam the riser with and decided against it.

There are quite a few folks that do not care for the look of the I beam construction, and it can be done by offsetting it in the strike area and use overlays to make it almost disappear.

Both of these have 1/4" G-10 I-beams.

[chefrvitale]

Great looking risers, is the dark wood Chechen?

[Kirkll]

Great looking risers, is the dark wood Chechen?

Macassar Ebony

[TC209X50]

Kirk,

Is there a specific draw weight that you deem I Beam is a must regardless of construction material? Excluding maybe a synthetic, G10 etc. as the main build material.

[Kirkll]

Kirk,

Is there a specific draw weight that you deem I Beam is a must regardless of construction material? Excluding maybe a synthetic, G10 etc. as the main build material.

It's really more of a matter of the riser wood i'm using, and riser length. Good solid hardwood on a 17"riser has very little flex to it at 40-50# draw weights, but above 50 you will start seeing and feeling a bit of flex to it even using bubinga or ebony.... if you are using a laminated riser with accent strips, or a footing, you will add strength to the riser .  But using softer woods like curly maple or walnut, anything over 50# should have an I-beam.

Some guys dont mind a bit of flex to a riser, but on softer hardwoods you can have easily have them develop compression cracks in the back of the shelf.

Using a G-10 I-beam adds mass weight to the riser too, besides zero flex, which is very desirable to many archers.

If you want a one wood riser. You can slice it up into 3 pieces and flip the  3/8" I-beam section around . A lot of the older bows were built this way in the 60's way using zebra wood. You have to look real close to see its not a solid block.  I will not build a riser out of one solid block myself unless its a slender one piece long bow using good hardwood.    Kirk

[chefrvitale]

Kirk, is there any advantage to using 2 -1/8th in beams of the same wood? When I do I-beam I have always done 2 thin.... I can't remember why, or who told me to do that, I might of just done that on my first bow and decided that was correct. But it's a little more work and it sounds like I am doing this for no reason.

[Kirkll]

Other than aesthetics and using two different types of material, I see no reason for it myself. I personally like a 5/16-3/8” I beam when using wood because I typically cut the shelf 1/8” past center.

When using thinner G-10 material, I offset the location accordingly to either hide it, or expose it without cutting through it. The I beam wont do you much good if ya sand through it in the strike area.

I’ve tried a few 3/4” I beams in the past, but didn’t care for the looks after shaping the riser and sanding into it at the thumb ledge and grip area… just looked weird to me….

[Jon Lipovac]

It is my thought and belief that a heavy composite like fiberglass or G10 as accent stripes whether by themselves or in conjunction with a footed riser do more for lateral stability than a simple I-Beam. A 1/4" or more  composite I-Beam, while very stout, is still delflected easier than even say 2-4 pieces of 1/16" G10 accent stripes running left/right.

[chefrvitale]

I couldn't fix my cracked bow and with enough confidence to shoot it...... however it's twin turned out great!

[Buemaker]

Looking great.

[Kirkll]

That's a beautiful piece of work there Chef.   

[Bryan Adolphe]

Yes looks awesome great looking bow, well done.

[Jon Lipovac]

Great looking bow!!!

[Bryan Adolphe]

Heres another but with an I beam, 1/2” wenge in see a crack  . I must of missed something .
I just finished this bow and shot it a doz times. 50@28

[Kirkll]

Is that the little crack at the back of the shelf right where the bocote meets the wenge going downward?  If so a couple shots of water thin super glue, should take care of it.  It isn't uncommon seeing wenge split like that.

[Bryan Adolphe]

Yes small crack right off the shelf i will remove the rest and ca it then shoot it for awhile and see if it continues to crack.

[chefrvitale]

I love bacote, that's a good looking bow. Rainy Sunday.... I might glue up some bacote and rosewood, see how they look together

[Kirkll]

It is my thought and belief that a heavy composite like fiberglass or G10 as accent stripes whether by themselves or in conjunction with a footed riser do more for lateral stability than a simple I-Beam. A 1/4" or more  composite I-Beam, while very stout, is still delflected easier than even say 2-4 pieces of 1/16" G10 accent stripes running left/right.

The only issue with running glass and even phenolic or G10 accent lines is that they often stand proud with any changes in MC levels. Even using G-10 for an I beam, you need to make damn sure that wood is bone dry before finishing or it can open up a wee bit and crank the finish. The back of the shelf is the most likely spot too.

I just run wood accent lines on footed risers myself, and use phenolic on the limb pads, and sometimes overlays.

[Crooked Stic]

I say the key to using composites for accents is using stabilized wood.