Primitive Archer

Main Discussion Area => Bows => Topic started by: Frode on July 17, 2010, 04:54:28 pm

Title: (Hickory) backing thickness
Post by: Frode on July 17, 2010, 04:54:28 pm
Hi all,
I've read of the backing wood overpowering the belly wood of a bow on occasion here, and as I'm finishing up my very first glue up (hickory backed elm), I'm wondering if there are any rules of thumb regarding thickness of backing.  Particularly in hickory, since that's what I'm using.  The backing strips I have are 1/8" thick, and even with sanding, stay pretty close to that.  Is that too much for, say, a 72" ntn, 40-ish@28" "longbow"?  Or is this too open a question?  ???
Thanks,
Frode
Title: Re: (Hickory) backing thickness
Post by: half eye on July 17, 2010, 05:14:44 pm
Hey Frode,
       I've made a lot of bows from elm.....self and backed and never had a problem with either tension or compression strength of the wood. I've backed with hard maple and that didn't cause any problem.....so even though you dont say how thick the elm is ....I do not believe you will have any problem with the elm standing up.
Rich
Title: Re: (Hickory) backing thickness
Post by: Frode on July 17, 2010, 05:26:27 pm
Hey Frode,
       I've made a lot of bows from elm.....self and backed and never had a problem with either tension or compression strength of the wood. I've backed with hard maple and that didn't cause any problem.....so even though you dont say how thick the elm is ....I do not believe you will have any problem with the elm standing up.
Rich
Oops!  I should've mentioned that  :-[ :)!  In this case, the elm runs from about 3/4" at the fades down to maybe 3/16" at the nocks, 1 1/4" wide at the center of the bow and 1/2" wide at the nocks.
Frode
Title: Re: (Hickory) backing thickness
Post by: Pat B on July 17, 2010, 05:58:41 pm
When I cut out hickory backing strips I cut them 3/16" and after sanding out the tool marks it is usually 1/8" or slightly less. You should be fine with what you have especially with the length and weight you are building. I haven't built many elm bows but have backed lots with hickory.
Title: Re: (Hickory) backing thickness
Post by: denny on July 17, 2010, 08:02:16 pm
I use 1/8 inch when I back with hickory or other woods. The only one I barrel taper is bamboo. Denny
Title: Re: (Hickory) backing thickness
Post by: elk country rp on July 17, 2010, 09:42:37 pm
i go thicker for ipe (~1/4"), but i like to keep it ~1/8" for everything else
Title: Re: (Hickory) backing thickness
Post by: Frode on July 18, 2010, 03:03:27 pm
Thanks everyone!
Frode
Title: Re: (Hickory) backing thickness
Post by: luke the drifter on July 19, 2010, 05:18:22 pm
i may have already ask this on this community forum but i am going to ask it again.  i have spliced two osage stave billits using a four inch double fish-tail splice.  i used tite-bond three glue.  the glue up could have been better but all things considered it turned out rather nice.  would it be better for me to use a quarter inch hickory backing strip if i am going for 72 inch,  40 to 50 lbs., by 30 -32 inch draw.  in y'all's opinion would it hold up under the pressure of tillering.  the grain and rings almost match up perfectly at the splice.  just wondering before i go any further.

Title: Re: (Hickory) backing thickness
Post by: Pat B on July 19, 2010, 06:03:05 pm
A 1/8" hickory backing strip will be sufficient to hold it together. If you are adding a handle riser that will add more strength to the splice.
Title: Re: (Hickory) backing thickness
Post by: luke the drifter on July 19, 2010, 11:13:44 pm
pat b.

that handle riser idea is one i probably should have already thought of but  i like it.